ORCID Profile
0000-0003-4666-2934
Current Organisation
Macquarie University
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Marine and Estuarine Ecology (incl. Marine Ichthyology) | Ecology | Environmental Science and Management | Biological Oceanography | Ecological Impacts of Climate Change | Oceanography | Conservation and Biodiversity | Fisheries Management | Behavioural Ecology | Wildlife and Habitat Management | Ecological Applications | Biological Oceanography | Chemical Oceanography | Environmental Management And Rehabilitation | Wildlife And Habitat Management | Physical Oceanography | Population, Ecological and Evolutionary Genetics | Population Ecology | Aboriginal and Torres Strait Islander Environmental Knowledge | Landscape Ecology | Marine And Estuarine Ecology (Incl. Marine Ichthyology) | Natural Resource Management |
ANZSRC Socio-Economic Objective (SEO)
Marine Flora, Fauna and Biodiversity | Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) | Ecosystem Adaptation to Climate Change | Marine Oceanic Processes (excl. climate related) | Ecosystem Assessment and Management of Marine Environments | Antarctic and Sub-Antarctic Flora, Fauna and Biodiversity | Ecosystem Assessment and Management of Antarctic and Sub-Antarctic Environments | Antarctic and Sub-Antarctic Oceanography | Conserving Natural Heritage | Marine protected areas | Integrated (ecosystem) assessment and management | Rehabilitation of degraded coastal and estuarine areas | Environmental policy, legislation and standards not elsewhere classified | Living resources (incl. impacts of fishing on non-target species) | Land and water management | Living resources (flora and fauna) | Physical and chemical conditions | Economic issues | Fisheries—recreational | Expanding Knowledge in the Biological Sciences | Fisheries—commercial | Rights to Environmental and Natural Resources (excl. Water Allocation) | Coastal and Estuarine Water Management
Related Links
Publications
To share or not to share in the emerging era of big data: perspectives from fish telemetry researchers on data sharing
Publisher: Canadian Science Publishing
Date: 08-2017
Abstract: The potential for telemetry data to answer complex questions about aquatic animals and their interactions with the environment is limited by the capacity to store, manage, and access data across the research community. Large telemetry networks and databases exist, but are limited by the actions of researchers to share their telemetry data. Promoting data sharing and understanding researchers’ views on open practices is a major step toward enhancing the role of big data in ecology and resources management. We surveyed 307 fish telemetry researchers to understand their perspectives and experiences on data sharing. A logistic regression revealed that data sharing was positively related to researchers with collaborative tendencies, who belong to a telemetry network, who are prolific publishers, and who express altruistic motives for their research. Researchers were less likely to have shared telemetry data if they engage in radio and (or) acoustic telemetry, work for regional government, and value the time it takes to complete a research project. We identify and provide ex les of both benefits and concerns that respondents have about sharing telemetry data.
Reciprocal homosexual mounting in Adelie Penguins Pygoscelis adeliae
Publisher: Informa UK Limited
Date: 06-1998
DOI: 10.1071/MU98015
Drone Observations of Marine Life and Human–Wildlife Interactions off Sydney, Australia
Publisher: MDPI AG
Date: 11-03-2022
Abstract: Drones have become popular with the general public for viewing and filming marine life. One amateur enthusiast platform, DroneSharkApp, films marine life in the waters off Sydney, Australia year-round and posts their observations on social media. The drone observations include the behaviours of a variety of coastal marine wildlife species, including sharks, rays, fur seals, dolphins and fish, as well as migratory species such as migrating humpback whales. Given the extensive effort and multiple recordings of the presence, behaviour and interactions of various species with humans provided by DroneSharkApp, we explored its utility for providing biologically meaningful observations of marine wildlife. Using social media posts from the DroneSharkApp Instagram page, a total of 678 wildlife videos were assessed from 432 days of observation collected by a single observer. This included 94 feeding behaviours or events for fur seals (n = 58) and dolphins (n = 33), two feeding events for white sharks and one feeding event for a humpback whale. DroneSharkApp documented 101 interactions with sharks and humans (swimmers and surfers), demonstrating the frequent, mainly innocuous human–shark overlap off some of Australia’s busiest beaches. Finally, DroneSharkApp provided multiple observations of humpback and dwarf minke whales with calves travelling north, indicating calving occurring well south of traditional northern Queensland breeding waters. Collaboration between scientists and citizen scientists such as those involved with DroneSharkApp can greatly and quantitatively increase the biological understanding of marine wildlife data.
Proxies of energy expenditure for marine mammals: an experimental test of “the time trap”
Publisher: Springer Science and Business Media LLC
Date: 18-09-2017
DOI: 10.1038/S41598-017-11576-4
Abstract: Direct measures of energy expenditure are difficult to obtain in marine mammals, and accelerometry may be a useful proxy. Recently its utility has been questioned as some analyses derived their measure of activity level by calculating the sum of accelerometry-based values and then comparing this summation to summed (total) energy expenditure (the so-called “time trap”). To test this hypothesis, we measured oxygen consumption of captive fur seals and sea lions wearing accelerometers during submerged swimming and calculated total and rate of energy expenditure. We compared these values with two potential proxies of energy expenditure derived from accelerometry data: flipper strokes and dynamic body acceleration (DBA). Total number of strokes, total DBA, and submergence time all predicted total oxygen consumption $$({\\boldsymbol{sV}}{{\\boldsymbol{O}}}_{{\\boldsymbol{2}}}$$ ( sV O 2 ml kg −1 ). However, both total DBA and total number of strokes were correlated with submergence time. Neither stroke rate nor mean DBA could predict the rate of oxygen consumption ( $$s\\mathop{{\\boldsymbol{V}}}\\limits^{{\\boldsymbol{.}}}{{\\boldsymbol{O}}}_{{\\boldsymbol{2}}}$$ s V . O 2 ml min −1 kg −1 ). The relationship of total DBA and total strokes with total oxygen consumption is apparently a result of introducing a constant (time) into both sides of the relationship. This experimental evidence supports the conclusion that proxies derived from accelerometers cannot estimate the energy expenditure of marine mammals.
Environmental correlates of relative abundance of potentially dangerous sharks in nearshore areas, southeastern Australia
Publisher: Inter-Research Science Center
Date: 12-07-2018
DOI: 10.3354/MEPS12611
Integrating research using animal-borne telemetry with the needs of conservation management
Publisher: Wiley
Date: 11-08-2016
Short-term behavioural response of bottlenose dolphins Tursiops aduncus to recreational powerboats
Publisher: Informa UK Limited
Date: 2008
Quantifying imperfect camera-trap detection probabilities: implications for density modelling
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/WR19040
Abstract: Abstract ContextData obtained from camera traps are increasingly used to inform various population-level models. Although acknowledged, imperfect detection probabilities within camera-trap detection zones are rarely taken into account when modelling animal densities. AimsWe aimed to identify parameters influencing camera-trap detection probabilities, and quantify their relative impacts, as well as explore the downstream implications of imperfect detection probabilities on population-density modelling. MethodsWe modelled the relationships between the detection probabilities of a standard camera-trap model (n=35) on a remotely operated animal-shaped soft toy and a series of parameters likely to influence it. These included the distance of animals from camera traps, animal speed, camera-trap deployment height, ambient temperature (as a proxy for background surface temperatures) and animal surface temperature. We then used this detection-probability model to quantify the likely influence of imperfect detection rates on subsequent population-level models, being, in this case, estimates from random encounter density models on a known density simulation. Key resultsDetection probabilities mostly varied predictably in relation to measured parameters, and decreased with an increasing distance from the camera traps and speeds of movement, as well as heights of camera-trap deployments. Increased differences between ambient temperature and animal surface temperature were associated with increased detection probabilities. Importantly, our results showed substantial inter-camera (of the same model) variability in detection probabilities. Resulting model outputs suggested consistent and systematic underestimation of true population densities when not taking imperfect detection probabilities into account. ConclusionsImperfect, and in idually variable, detection probabilities inside the detection zones of camera traps can compromise resulting population-density estimates. ImplicationsWe propose a simple calibration approach for in idual camera traps before field deployment and encourage researchers to actively estimate in idual camera-trap detection performance for inclusion in subsequent modelling approaches.
Born to be free? Assessing the viability of releasing captive-bred wobbegongs to restock depleted populations
Publisher: Frontiers Media SA
Date: 09-04-2015
Coastal polynyas: Winter oases for subadult southern elephant seals in East Antarctica
Publisher: Springer Science and Business Media LLC
Date: 16-02-2018
DOI: 10.1038/S41598-018-21388-9
Abstract: Antarctic coastal polynyas are regions of persistent open water and are thought to be key bio-physical features within the sea-ice zone. However, their use by the upper trophic levels of ecosystems remains unclear. A unique bio-physical dataset recorded by southern elephant seals reveals that East Antarctic polynyas are a key winter foraging habitat for male seals. During their post-moult trips from Isles Kerguelen to the Antarctic continental shelf, a total of 18 out of 23 seals visited 9 different polynyas, spending on average 25 ± 20% (up to 75%) of their total trip time inside polynyas. Changes in seal foraging and ing behaviours are observed inside polynyas as compared to outside polynyas. Two polynya usages by seals are observed for the inactive and active polynya phases, pointing to different seasonal peaks in prey abundance. During the active polynya phase, we link seal foraging behaviour to changes in the physical stability of the water-column, which likely impact the seasonal biological dynamics within polynyas.
Controls on Dense Shelf Water Formation in Four East Antarctic Polynyas
Publisher: American Geophysical Union (AGU)
Date: 29-11-2022
DOI: 10.1029/2022JC018804
Abstract: Coastal polynyas are key formation regions for dense shelf water (DSW) that ultimately contributes to the ventilation of the ocean abyss. However, not all polynyas form DSW. We examine how the physiographic setting, water‐mass distribution and transformation, water column stratification, and sea‐ice production regulate DSW formation in four East Antarctic coastal polynyas. We use a salt budget to estimate the relative contribution of sea‐ice production and lateral advection to the monthly change in salinity in each polynya. DSW forms in Mackenzie polynya due to a combination of physical features (shallow water depth and a broad continental shelf) and high sea‐ice production. Sea‐ice formation begins early (March) in Mackenzie polynya, counteracting fresh advection and establishing a salty mixed layer in autumn that preconditions the water column for deep convection in winter. Sea‐ice production is moderate in the other three polynyas, but saline DSW is not formed (a fresh variety is formed in the Barrier polynya). In the Shackleton polynya, brine rejection during winter is insufficient to overcome the very fresh autumn mixed layer. In Vincennes Bay, a strong inflow of modified Circumpolar Deep Water stratifies the water column, hindering deep convection and DSW formation. Our study highlights that DSW formation in a given polynya depends on a complex combination of factors, some of which may be strongly altered under a changing climate, with potentially important consequences for the ventilation of the deep ocean, the global meridional overturning circulation, and the transport of ocean heat to Antarctic ice shelves.
Conserving coral reef organisms that lack larval dispersal: are networks of Marine Protected Areas good enough?
Publisher: Frontiers Media SA
Date: 03-03-2015
The R package EchoviewR for automated processing of active acoustic data using Echoview
Publisher: Frontiers Media SA
Date: 25-02-2015
Fine-scale three-dimensional spatial use by diving, lactating female Weddell seals Leptonychotes weddellii
Publisher: Inter-Research Science Center
Date: 2002
DOI: 10.3354/MEPS242275
Movement responses to environment: fast inference of variation among southern elephant seals with a mixed effects model
Publisher: Cold Spring Harbor Laboratory
Date: 04-05-2018
DOI: 10.1101/314690
Abstract: Like many species, movement patterns of southern elephant seals ( Mirounga leonina ) are being influenced by long-term environmental change. These seals migrate up to 4000 km from their breeding colonies, foraging for months in a variety of Southern Ocean habitats. Understanding how movement patterns vary with environmental features and how these relationships differ among in iduals employing different foraging strategies can provide insight into foraging performance at a population level. We apply new fast-estimation tools to fit mixed effects within a random walk movement model, rapidly inferring among-in idual variability in southern elephant seal environment-movement relationships. We found that seals making foraging trips to the sea-ice on or near the Antarctic continental shelf consistently reduced speed and directionality (move persistence) with increasing sea ice coverage and had variable responses to chlorophyll a concentration, whereas seals that foraged pelagically reduced move persistence in regions where circumpolar deep water shoaled. Given future climate scenarios, pelagic foragers may encounter more productive habitat but sea-ice foragers may see reduced habitat availability. Our approach is scalable to large telemetry data sets and allows flexible combinations of mixed effects to be evaluated via model selection, thereby illuminating the ecological context of animal movements that underlie habitat use.
Behaviour of Chilean and Peale's dolphins in southern Chile
Publisher: Cambridge University Press (CUP)
Date: 03-04-2016
DOI: 10.1017/S0025315414000216
Abstract: Assessing the behavioural patterns of animals is an increasingly important field in conservation biology, as it may assist in the prediction of how animals respond to rapid changes in the environment. Comparing the behavioural patterns of sympatric species can also give insights into the mechanisms that allow similar species to coexist. We undertook dolphin group follows in order to quantify the behavioural patterns of the sympatric Chilean and Peale's dolphins in southern Chile. Markov chains showed that these species differed significantly in time allocated to each of the five different behavioural states, but travelling was the most frequent behavioural state observed for both species. Six (out of 25) behavioural transitions were found to be different between species. In addition, group size and group dispersion were highly associated with specific behavioural states. Larger groups were more likely to socialize, while small groups were more likely to rest. For both species resting was mostly observed in tight groups, while foraging/feeding and travelling were related to intermediate group dispersion. Socializing differed between species, occurring in tight groups for Peale's dolphins and dispersed groups for Chilean dolphins. Overall, there were significant differences in behavioural patterns between the two species. These dissimilarities may represent evidence of different strategies (i.e. habitat use patterns and foraging) these two species employ which allow them to coexist. The information generated in this study will contribute to the development of better predictive models on how animals may respond to a changing environment and to the potential effects of human induced activities.
Acoustic telemetry around Western Australia's oil and gas infrastructure helps detect the presence of an elusive and endangered migratory giant
Publisher: Frontiers Media SA
Date: 05-08-2021
DOI: 10.3389/FMARS.2021.631449
Abstract: Subsea infrastructure of the oil and gas industry attracts commercial fish species as well as megafauna including sea lions, turtles, sharks and whales. Potential impacts of this attraction, whether positive or negative, are unknown. As part of a pilot study, we deployed acoustic telemetry equipment around offshore infrastructure to assess its effectiveness in detecting tagged marine animals and to gain insights into patterns of megafauna occurrence around these structures. Acoustic receivers were placed around four oil and gas platforms and on two remotely operated vehicles (ROVs) on Australia’s North West Shelf. Two whale sharks ( Rhincodon typus ) tagged in the World Heritage Ningaloo Reef Marine Park were detected at two platforms, North Rankin A and Pluto, located up to 340 km to the northeast. The shark at North Rankin A was detected infrequently and only 15 times over ∼6 weeks. The shark at Pluto was detected each day of the 24-day deployment, in total 4,894 times. Detections at Pluto platform were highest during the day, with peaks at dusk and dawn. Our study indicates that acoustic telemetry around platforms may be an effective method for understanding how marine megafauna utilise these structures. We recommend collaborating with industry to undertake receiver detection range testing to understand the effectiveness of the method. Furthermore, future studies should co-occur with tagging programs at sites like Ningaloo Reef and around the structures themselves to maximise the probability of detecting animals at these sites, thereby improving our understanding of how marine megafauna interact with these structures.
Three-dimensional dive profiles of free-ranging Weddell seals
Publisher: Springer Science and Business Media LLC
Date: 23-06-2000
The Ecology of Human Mobility
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.TREE.2016.12.006
Abstract: Mobile phones and other geolocated devices have produced unprecedented volumes of data on human movement. Analysis of pooled in idual human trajectories using big data approaches has revealed a wealth of emergent features that have ecological parallels in animals across a erse array of phenomena including commuting, epidemics, the spread of innovations and culture, and collective behaviour. Movement ecology, which explores how animals cope with and optimize variability in resources, has the potential to provide a theoretical framework to aid an understanding of human mobility and its impacts on ecosystems. In turn, big data on human movement can be explored in the context of animal movement ecology to provide solutions for urgent conservation problems and management challenges.
Hierarchical influences of prey distribution on patterns of prey capture by a marine predator
Publisher: Wiley
Date: 02-05-2017
Global spatial risk assessment of sharks under the footprint of fisheries
Publisher: Springer Science and Business Media LLC
Date: 06-2013
DOI: 10.1038/S41586-019-1444-4
Abstract: Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.
The effect of road-type and distance transported on behaviour, physiology and carcass quality of farmed red deer (Cervus elaphus)
Publisher: Elsevier BV
Date: 1997
The Use of Carcasses for the Analysis of Cetacean Population Genetic Structure: A Comparative Study in Two Dolphin Species
Publisher: Public Library of Science (PLoS)
Date: 31-05-2011
Marine Mammals Exploring the Oceans Pole to Pole: A Review of the MEOP Consortium
Publisher: The Oceanography Society
Date: 06-2017
Optimising the design of large-scale acoustic telemetry curtains
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/MF16126
Abstract: Broad-scale acoustic telemetry networks are being established worldwide. The 10-year anniversary of the Integrated Marine Observing System’s Animal Tracking Facility provided the opportunity to assess the efficiency of one of the first national-scale acoustic telemetry networks. Acoustic networks are comprised of acoustic receiver arrays that detect high-frequency transmitters attached to animals that pass within detection range. Herein we assessed the efficiency of eight curtains to detect passing animals by calculating the standardised mean number of detections and transmitters detected at each station. The aim was to determine how many receivers could be decommissioned from each curtain while maintaining its integrity (i.e. detection of all species passing the array). Pivotal locations were defined as the furthest station at which all species would still be detected and where at least 75% of the detections and transmitters would still be detected. By applying these criteria, we were able to improve the cost-effectiveness of our network significantly, reducing the number of stations from 132 to 85 (64% of the original network), yet still retaining 84% of total detections, 86% of transmitters and 100% of detected species. The present study provides a useful framework for refining acoustic telemetry networks.
Reef shark movements relative to a coastal marine protected area.
Publisher: Elsevier BV
Date: 2016
Estimates of the Southern Ocean general circulation improved by animal‐borne instruments
Publisher: American Geophysical Union (AGU)
Date: 03-12-2013
DOI: 10.1002/2013GL058304
Abstract: Over the last decade, several hundred seals have been equipped with conductivity‐temperature‐depth sensors in the Southern Ocean for both biological and physical oceanographic studies. A calibrated collection of seal‐derived hydrographic data is now available, consisting of more than 165,000 profiles. The value of these hydrographic data within the existing Southern Ocean observing system is demonstrated herein by conducting two state estimation experiments, differing only in the use or not of seal data to constrain the system. Including seal‐derived data substantially modifies the estimated surface mixed‐layer properties and circulation patterns within and south of the Antarctic Circumpolar Current. Agreement with independent satellite observations of sea ice concentration is improved, especially along the East Antarctic shelf. Instrumented animals efficiently reduce a critical observational gap, and their contribution to monitoring polar climate variability will continue to grow as data accuracy and spatial coverage increase.
Advances in New Zealand mammalogy 1990–2000
Publisher: Informa UK Limited
Date: 03-2001
Virological Sampling of Inaccessible Wildlife with Drones
Publisher: MDPI AG
Date: 02-06-2018
DOI: 10.3390/V10060300
Decadal changes in habitat characteristics influence population trajectories of southern elephant seals
Publisher: Wiley
Date: 12-07-2017
DOI: 10.1111/GCB.13776
Abstract: Understanding ergent biological responses to climate change is important for predicting ecosystem level consequences. We use species habitat models to predict the winter foraging habitats of female southern elephant seals and investigate how changes in environmental variables within these habitats may be related to observed decreases in the Macquarie Island population. There were three main groups of seals that specialized in different ocean realms (the sub-Antarctic, the Ross Sea and the Victoria Land Coast). The physical and climate attributes (e.g. wind strength, sea surface height, ocean current strength) varied amongst the realms and also displayed different temporal trends over the last two to four decades. Most notably, sea ice extent increased on average in the Victoria Land realm while it decreased overall in the Ross Sea realm. Using a species distribution model relating mean residence times (time spent in each 50 × 50 km grid cell) to 9 climate and physical co-variates, we developed spatial predictions of residence time to identify the core regions used by the seals across the Southern Ocean from 120°E to 120°W. Population size at Macquarie Island was negatively correlated with ice concentration within the core habitat of seals using the Victoria Land Coast and the Ross Sea. Sea ice extent and concentration is predicted to continue to change in the Southern Ocean, having unknown consequences for the biota of the region. The proportion of Macquarie Island females (40%) utilizing the relatively stable sub-Antarctic region, may buffer this population against longer-term regional changes in habitat quality, but the Macquarie Island population has persistently decreased (-1.45% per annum) over seven decades indicating that environmental changes in the Antarctic are acting on the remaining 60% of the population to impose a long-term population decline in a top Southern Ocean predator.
A case for restoring unity between biotelemetry and bio-logging to enhance animal tracking research
Publisher: Canadian Science Publishing
Date: 2021
Abstract: Monitoring animals with electronic tags is an increasingly important tool for fundamental and applied ecological research. Based on the size of the system under study, the ability to recapture the animal, and research medium (e.g., aerial, freshwater, saltwater, terrestrial), tags selected may either log data in memory (bio-logging), transmit it to a receiver or satellite (biotelemetry), or have a hybrid design. Over time, we perceive that user groups are erging based on increasing use of technology specific terms, favouring either bio-logging or biotelemetry. It is crucial to ensure that a ide does not become entrenched in the community because it will likely hinder efforts to advance field and analytical methods and reduce accessibility of animal tracking with electronic tags to early-career and new researchers. We discuss the context for this emerging problem and the evidence that this is manifesting within the scientific community. Finally, we suggest how the animal tracking community may work to address this issue to maximize the benefits of information transfer and integration between users of the two technologies.
Optimizing lifetime reproductive output: Intermittent breeding as a tactic for females in a long‐lived, multiparous mammal
Publisher: Wiley
Date: 23-11-2017
Abstract: In iteroparous species, intermittent breeding is an important life-history tactic that can greatly affect animal population growth and viability. Despite its importance, few studies have quantified the consequences of breeding pauses on lifetime reproductive output, principally because calculating lifetime reproductive output requires knowledge of each in idual's entire reproductive history. This information is extremely difficult to obtain in wild populations. We applied novel statistical approaches that account for uncertainty in state assessment and in idual heterogeneity to an 18-year capture-recapture dataset of 6,631 female southern elephant seals from Macquarie Island. We estimated survival and breeding probabilities, and investigated the consequences of intermittent breeding on lifetime reproductive output. We found consistent differences in females' demographic performance between two heterogeneity classes. In particular, breeding imbued a high cost on survival in the females from the heterogeneity class 2, assumed to be females of lower quality. In idual quality also appeared to play a major role in a female's decision to skip reproduction with females of poorer quality more likely to skip breeding events than females of higher quality. Skipping some breeding events allowed females from both heterogeneity classes to increase lifetime reproductive output over females that bred annually. However, females of lower quality produced less offspring over their lifetime. Intermittent breeding seems to be used by female southern elephant seals as a tactic to offset reproductive costs on survival and enhance lifetime reproductive output but remains unavoidable and driven by in idual-specific constraints in some other females.
Shared Reproductive State Enhances Female Associations in Dolphins
Publisher: Hindawi Limited
Date: 2008
DOI: 10.1155/2008/498390
Abstract: Female bottlenose dolphins (genus Tursiops ) usually associate at moderate level with other females within social clusters called bands or cliques. It has been suggested that reproductive state may play the predominant role in determining associations within female T. truncatus bands. Here, we test the hypothesis that reproductive state correlates with associations of female Indo-Pacific bottlenose dolphins ( T. aduncus ). We found that females in similar reproductive state, which included females from late pregnancy to the first year of their calves' life or females from early pregnancy to their calves' newborn period, had higher-association coefficients with each other than they did with females in different reproductive states (females with older calves or without calves). This was observed both within and across social clusters suggesting that reproductive state, at least for pregnant females and those with young calves, plays an important role in determining who to associate with. However, a female's most frequent associate was not always with another in similar reproductive state. We suggest that several factors, including reproductive state, may be of importance in determining associations of female bottlenose dolphins.
Niche differentiation of bottlenose dolphin species in South Australia revealed by stable isotopes and stomach contents
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/WR10108
Abstract: Context Animal species with overlapping ranges are common worldwide, but how these species coexist is less obvious. Dolphins are protected in Australia and yet little information is available on their resource use which is essential for successful management and conservation. Aim The aim of this study was to determine the degree of overlap in diet and feeding ecology of the two Tursiops spp. that have overlapping ranges in South Australia. Methods Stomach content (91 Tursiops sp. and 14 T. truncatus) and stable isotope (δ13C, δ15N) analyses (39 Tursiops sp. and 14 T. truncatus) were conducted. Carcasses of dolphins were opportunistically collected between 1974 and 2005. Diet was quantified by frequency of occurrence (FOO) and numerical abundance (NA) of prey. Key results Delta13C from teeth revealed distinct differences in primary source of carbon, corresponding to coastal (Tursiops sp. n = 39, = –12.24, s.d. = 1.32) and offshore habitats (T. truncatus n = 14, = –14.21, s.d. = 0.55). Differences in δ15N revealed Tursiops sp. ( = 11.66, s.d. = 0.58) feeds at a lower trophic level than T. truncatus ( = 14.29, s.d. = 0.88). Stomach content analyses for Tursiops sp. corroborated stable isotope results. There was a significant difference between the diets of Tursiops sp. from north Spencer Gulf and south Spencer Gulf (ANOSIM R = 0.249, P = 0.001). Prey were generally demersal in habit with the most important from the cephalopod families Octopodidae, Sepiidae and Loliginidae and fish families Carangidae, Clupeidae, Terapontidae and Apogonidae. For T. truncatus there were insufficient stomach contents for assessment. Conclusions South Australian bottlenose dolphin species exhibit distinct niche differentiation with clear evidence of regional variation in the diet of Tursiops sp. Implications The between and within species diet differentiation demonstrated, highlights the importance of regional management. Such results are internationally significant as coastal and offshore forms of Tursiops spp. occur worldwide.
Assessing the distribution and relative abundance of wobbegong sharks (Orectolobidae) in New South Wales, Australia, using recreational scuba-divers
Publisher: EDP Sciences
Date: 07-2009
DOI: 10.1051/ALR/2009046
Convergence of marine megafauna movement patterns in coastal and open oceans
Publisher: Proceedings of the National Academy of Sciences
Date: 26-02-2018
Abstract: Understanding the key drivers of animal movement is crucial to assist in mitigating adverse impacts of anthropogenic activities on marine megafauna. We found that movement patterns of marine megafauna are mostly independent of their evolutionary histories, differing significantly from patterns for terrestrial animals. We detected a remarkable convergence in the distribution of speed and turning angles across organisms ranging from whales to turtles (epitome for the slowest animals on land but not at sea). Marine megafauna show a prevalence of movement patterns dominated by search behavior in coastal habitats compared with more directed, ballistic movement patterns when the animals move across the open ocean. The habitats through which they move will therefore need to be considered for effective conservation.
What Makes an Australian Sea Lion (Neophoca cinerea) Male's Bark Threatening?
Publisher: American Psychological Association (APA)
Date: 2011
DOI: 10.1037/A0024513
Abstract: In mammals, vocal signals are produced in many social contexts and convey erse information about the emitter (social rank, in idual identity, body size-condition). To understand their biological function, the authors find it is not only important to estimate the information about the signaler encoded in the signal but also to determine if and how this information is perceived by the receiver. In male pinnipeds (phocids, otariids, and odobenids) vocal signaling plays an important role in the breeding season during the defense of territories, females, or both. In this article, the authors investigated 2 key acoustic features that Australian sea lion (Neophoca cinerea) males most likely rely on to assess the threat level posed by potential rivals, by manipulating bark rhythmicity and spectral characteristics. Bark series that show accelerated rhythmicity and higher formants elicited stronger responses.
Challenges of collecting blow from small cetaceans
Publisher: Wiley
Date: 10-2019
DOI: 10.1002/ECS2.2901
Nuclear and mitochondrial DNA reveals isolation of imperilled grey nurse shark populations (Carcharias taurus)
Publisher: Wiley
Date: 14-10-2009
New Zealand southern right whale (Eubalaena australis; Tohorā nō Aotearoa) behavioural phenology, demographic composition, and habitat use in Port Ross, Auckland Islands over three decades: 1998–2021
Publisher: Springer Science and Business Media LLC
Date: 08-2022
DOI: 10.1007/S00300-022-03076-7
Abstract: Changes in habitat availability and prey abundance are predicted to adversely influence survival and reproduction of wildlife in the Southern Ocean. Some populations of southern right whale (SRW Eubalaena australis ) are showing dramatic changes in habitat use. Surveys were undertaken in the austral winters of 2020 and 2021 at the key nursery and socialising ground for New Zealand SRWs: Port Ross, Auckland Islands, with 548 encounters and 599 skin biopsy s les collected. Data from these two surveys spanned peak periods of use and were used to test the hypothesis there have been shifts in the phenology, demographic composition and behaviour of SRWs using the Auckland Islands over the past three decades. The behavioural phenology and demographic composition of SRW resembles that observed in the 1990s. In contrast, the proportion of groups containing cow-calf pairs increased from 20% in the 1998 survey to 50% in 2020/21. These changes are consistent with a growing population undergoing strong recruitment, not limited by food resources. Continued use of Port Ross by all SRW demographic classes confirms this as key habitat for SRW in New Zealand waters, and we support increased enforcement of existing management measures to reduce whale-vessel interactions in this remote subantarctic archipelago.
A Southern Ocean archipelago enhances feeding opportunities for a krill predator
Publisher: Wiley
Date: 11-09-2020
DOI: 10.1111/MMS.12645
Rapid Onset of Maternal Vocal Recognition in a Colonially Breeding Mammal, the Australian Sea Lion
Publisher: Public Library of Science (PLoS)
Date: 13-08-2010
To catch or to sight? A comparison of demographic parameter estimates obtained from mark-recapture and mark-resight models
Publisher: Springer Science and Business Media LLC
Date: 03-07-2014
Seals collect more Southern Ocean data
Publisher: Springer Science and Business Media LLC
Date: 09-2014
DOI: 10.1038/513033E
Predicting potential future reduction in shark bites on people
Publisher: The Royal Society
Date: 03-2021
DOI: 10.1098/RSOS.201197
Abstract: Despite the low chance of a person being bitten by a shark, there are serious associated costs. Electronic deterrents are currently the only types of personal deterrent with empirical evidence of a substantial reduction in the probability of being bitten by a shark. We aimed to predict the number of people who could potentially avoid being bitten by sharks in Australia if they wear personal electronic deterrents. We used the Australian Shark Attack File from 1900 to 2020 to develop sinusoidal time-series models of per capita incidents, and then stochastically projected these to 2066. We predicted that up to 1063 people (range: 185–2118) could potentially avoid being bitten across Australia by 2066 if all people used the devices. Avoiding death and injury of people over the next half-century is of course highly desirable, especially when considering the additional costs associated with the loss of recreational, commercial and tourism revenue potentially in the tens to hundreds of millions of dollars following clusters of shark-bite events.
Dysfunctional attitudes in former psychiatric inpatients
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-1986
DOI: 10.1097/00005053-198611000-00004
Abstract: In order to test the hypothesis that patients who are predisposed to depression have an enduring cognitive style, dysfunctional attitudes (Dysfunctional Attitudes Schedule), neuroticism and extraversion (Maudsley Personality Inventory), and severity of depression (Levine-Pilowsky Depression Questionnaire) were measured in a survey of former patients with previous diagnoses of either depressive or nondepressive psychiatric conditions. We found that there were no significant differences in dysfunctional attitudes between these groups of patients and that their scores were similar to those reported for normal populations. There was, however, a correlation between introversion and high dysfunctional attitude scores. Possible implications regarding interactions between cognitive style, personality, and predisposition toward depression are discussed as well as a suggestion that a history of a suicide attempt may predict a poor response to cognitive psychotherapy.
Response of travelling bottlenose dolphins (Tursiops aduncus) to experimental approaches by a powerboat in Jervis Bay, New South Wales, Australia
Publisher: Elsevier BV
Date: 02-2006
Characterization of 12 novel microsatellite loci and cross-amplification of four loci in the endangered Australian sea lion (Neophoca cinerea)
Publisher: Springer Science and Business Media LLC
Date: 06-10-2012
Population histories of right whales (Cetacea: Eubalaena) inferred from mitochondrial sequence diversities and divergences of their whale lice (Amphipoda: Cyamus)
Publisher: Wiley
Date: 10-08-2005
The memory remains: long-term vocal recognition in Australian sea lions
Publisher: Springer Science and Business Media LLC
Date: 06-05-2010
DOI: 10.1007/S10071-010-0322-0
Abstract: The ability to recognize other in iduals plays an important role in mediating social interactions. As longitudinal studies are challenging, there is only limited evidence of long-term memory of in iduals and concepts in mammals. We examined the ability of six wild Australian sea lions to discriminate between the voice of their mother and another adult female, both while they were dependent on their mother and when they were independent, 2 years after weaning. Here, we show that even after a long period of independence, juveniles retain the ability to identify their mother's voice. Both when dependent and independent, animals showed stronger responses to maternal calls than to the calls of another female. This demonstration of recognition provides rare evidence of the long-term memory capabilities of wild mammals.
Genetic structure and signatures of selection in grey reef sharks (Carcharhinus amblyrhynchos)
Publisher: Springer Science and Business Media LLC
Date: 19-04-2017
DOI: 10.1038/HDY.2017.21
Paternity analysis shows experience, not age, enhances mating success in an aquatically mating pinniped, the Weddell seal (Leptonychotes weddellii)
Publisher: Springer Science and Business Media LLC
Date: 29-11-2006
Variability in prey field structure drives inter-annual differences in prey encounter by a marine predator, the little penguin
Publisher: The Royal Society
Date: 09-2022
DOI: 10.1098/RSOS.220028
Abstract: Understanding how marine predators encounter prey across patchy landscapes remains challenging due to difficulties in measuring the three-dimensional structure of pelagic prey fields at scales relevant to animal movement. We measured at-sea behaviour of a central-place forager, the little penguin ( Eudyptula minor ), over 5 years (2015–2019) using GPS and e loggers. We made contemporaneous measurements of the prey field within the penguins' foraging range via boat-based acoustic surveys. We developed a prey encounter index by comparing estimates of acoustic prey density encountered along actual penguin tracks to those encountered along simulated penguin tracks with the same characteristics as real tracks but that moved randomly through the prey field. In most years, penguin tracks encountered prey better than simulated random movements greater than 99% of the time, and penguin e depths matched peaks in the vertical distribution of prey. However, when prey was unusually sparse and/or deep, penguins had worse than random prey encounter indices, exhibited es that mismatched depth of maximum prey density, and females had abnormally low body mass (5.3% lower than average). Reductions in prey encounters owing to decreases in the density or accessibility of prey may ultimately lead to reduced fitness and population declines in central-place foraging marine predators.
A citizen science approach to long‐term monitoring of humpback whales (Megaptera novaeangliae) off Sydney, Australia
Publisher: Wiley
Date: 21-10-2019
DOI: 10.1111/MMS.12651
Abstract: The Cape Solander Whale Migration Study is a citizen science project that annually counts northward migrating humpback whales ( Megaptera novaeangliae ) off Cape Solander, Sydney, Australia. Dedicated observers have compiled a 20‐year data set (1997–2017) of shore‐based observations from Cape Solander's high vantage point. Using this long‐term data set collected by citizen scientists, we sought to estimate the humpback whale population trend as it continues to recover postexploitation. We estimated an exponential growth rate of 0.099 (95% CI = 0.079–0.119) using a generalized linear model, based on observer effort (number of observation days) and number of whales observed, equating to 10% per annum growth in sightings since 1997. We found that favorable weather conditions for spotting whales off Cape Solander consisted of winds km/hr from a southerly through a north westerly direction. Incidental observations of other cetacean species included the endangered blue whale ( Balaenoptera musculus ) and data deficient species such as killer whales ( Orcinus orca ) and false killer whales ( Pseudorca crassidens ). Citizen science‐based studies can provide a cost‐effective approach to monitoring wildlife over the time necessary to detect change in a population. Information obtained from citizen science projects like this may help inform policy makers responsible for State and Federal protection of cetaceans in Australian waters and beyond.
aniMotum, an R package for animal movement data: Rapid quality control, behavioural estimation and simulation
Publisher: Wiley
Date: 26-01-2023
Abstract: Animal tracking data are indispensable for understanding the ecology, behaviour and physiology of mobile or cryptic species. Meaningful signals in these data can be obscured by noise due to imperfect measurement technologies, requiring rigorous quality control as part of any comprehensive analysis. State–space models are powerful tools that separate signal from noise. These tools are ideal for quality control of error‐prone location data and for inferring where animals are and what they are doing when they record or transmit other information. However, these statistical models can be challenging and time‐consuming to fit to erse animal tracking data sets. The R package aniMotum eases the tasks of conducting quality control on and inference of changes in movement from animal tracking data. This is achieved via: (1) a simple but extensible workflow that accommodates both novice and experienced users (2) automated processes that alleviate complexity from data processing and model specification/fitting steps (3) simple movement models coupled with a powerful numerical optimization approach for rapid and reliable model fitting. We highlight aniMotum 's capabilities through three applications to real animal tracking data. Full R code for these and additional applications is included as Supporting Information, so users can gain a deeper understanding of how to use aniMotum for their own analyses.
Multi-event modeling of true reproductive states of individual female right whales provides new insights into their decline
Publisher: Frontiers Media SA
Date: 06-10-2022
DOI: 10.3389/FMARS.2022.994481
Abstract: Abundance and population trends of Critically Endangered North Atlantic right whales ( Eubalaena glacialis , NARW) have been estimated using mark-recapture analyses where an in idual’s state is based upon set delineations of age, using historical estimates of age at first reproduction. Here we assigned in idual females to states based upon their reproductive experience, rather than age. We developed a Bayesian mark-recapture-recovery model to investigate how survival, recapture, site-fidelity and dead-recovery probabilities vary for female NARW in different states, using data collected from 1977-2018. States were assigned as calves for in iduals in their first year pre-breeder for in iduals greater than one year of age who had yet to produce a calf, or breeder if an in idual had reproduced. A decline in abundance of female NARW was seen starting in 2014, with 185 females declining yearly to 142 by 2018. The largest decline was seen in breeding females, with 72 estimated to be alive at the beginning of 2018, while female pre-breeder abundance plateaued at around 70 between 2011- 2018. Females born from 2000 onwards had an average 4% (95% CI:0.03-0.06) chance of transitioning from pre-breeder to breeder, compared to 8% (95%CI:0.06-0.1) for females born prior. This reduction in transition rate from non-breeder to breeder for the current cohort resulted in breeding females declining to 51% of the female population by 2018. We show that a collapse in fecundity of breeding females, and the failure of pre-breeders to start breeding, is an important factor in understanding the current decline in abundance of the NARW.
Adult male Australian sea lion barking calls reveal clear geographical variations
Publisher: Elsevier BV
Date: 11-2014
Temporal variation in the vertical stratification of blubber fatty acids alters diet predictions for lactating Weddell seals
Publisher: Elsevier BV
Date: 11-2007
Now is the time to protect the Arctic
Publisher: American Association for the Advancement of Science (AAAS)
Date: 09-12-2016
How does Australia’s largest dolphin-watching industry affect the behaviour of a small and resident population of Indo-Pacific bottlenose dolphins?
Publisher: Elsevier BV
Date: 04-2012
DOI: 10.1016/J.JENVMAN.2011.11.002
Abstract: The small, genetically distinct population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Port Stephens, New South Wales (NSW), is the target of the largest dolphin-watching industry in Australia and is located within the Port Stephens - Great Lakes Marine Park that was created in 2005. The effects of this industry have been identified as of significant management importance by the Marine Parks Authority NSW. Accordingly, the impact of commercial dolphin-watching boats was investigated from boat-based surveys from August 2008 to August 2009. Presence of dolphin-watching boats altered both the dolphins' behavioural states and activity budgets. Dolphins spent 66.5% less time feeding and 44.2% less time socialising, spent four times more milling, and were never observed to rest in the presence of dolphin-watching boats. Moreover, dolphin groups were more cohesive during dolphin-watching boat encounters and dolphins tended to avoid tour boats. These effects were exacerbated as the number of boats increased and the distance from boats decreased. The rate of approach was high with boats approaching each dolphin group three times per day in winter and six times in summer. Moreover, groups of dolphins with newborns were approached closer than state regulated minimum approach distances in nine out of ten encounters. Globally, dolphin-watching industries frequent small resident groups of coastal dolphins and effects are likely to be similar. We suggest that existing controls are inadequate and that these together with additional regulations be enforced by a regular presence of authorities. We suggest no more than one dolphin-watching boat within 50 m of a group of dolphins, or 100 m if calves are present. Operating times of dolphin-watching boats should be restricted in numbers after 1 pm, i.e., during preferred foraging times for dolphins. Additionally, exclusion zones should be considered to reduce pressure on dolphins undertaking critical activities such as feeding and resting. We recommend monitoring the effectiveness of new regulations that are incorporated in the reviewed marine park management plan in 2012 for a period of three years.
Foraging while breeding: alternative mating strategies by male Weddell seals?
Publisher: Wiley
Date: 12-2007
DOI: 10.1002/AQC.915
A BIOPSY POLE SYSTEM FOR BOW‐RIDING DOLPHINS: SAMPLING SUCCESS, BEHAVIORAL RESPONSES, AND TEST FOR SAMPLING BIAS
Publisher: Wiley
Date: 21-12-2006
Australian sperm whales from different whaling stocks belong to the same population
Publisher: Wiley
Date: 11-01-2021
DOI: 10.1002/AQC.3494
Abstract: Understanding the factors driving population structure in marine mammals is needed to evaluate the impacts of previous exploitation, current anthropogenic threats, conservation status, and success of population recovery efforts. Sperm whales are characterized by a worldwide distribution, low genetic ersity, complex patterns of social and genetic structure that differ significantly within and between ocean basins, and a long history of being commercially whaled. In Australia, sperm whales from the (International Whaling Commission assigned) southern hemisphere ‘Division 5’ stock were very heavily exploited by whaling. The present study assessed the potential effects of whaling on the genetic ersity of sperm whales in Australia and the population genetic structure of these whales within a global context. A combination of historical and contemporary sperm whale s les ( n = 157) were analysed across six regions, from south‐eastern Australia (‘Division 6’ stock in the Pacific Ocean) to south‐western Australia (‘Division 5’ stock in the Indian Ocean). Sperm whales s led from the ‘Division 5’ and ‘Division 6’ stocks belong to the same population based on nuclear and mitochondrial DNA (mtDNA) analyses. Four novel sperm whale mtDNA haplotypes were identified in animals from Australian waters. Levels of genetic ersity were low in Australian sperm whales but were similar to those previously reported for populations in the Indian and Pacific Oceans. Given the genetic distinctiveness of sperm whales in Australian waters from other regions in the Pacific and Indian Oceans, and the lack of recovery in population numbers, further scientific studies are needed to increase our understanding of population dynamics and the effectiveness of threat management strategies in this species.
Effect of proximity to the shelf edge on the diet of female Australian fur seals
Publisher: Inter-Research Science Center
Date: 24-05-2007
DOI: 10.3354/MEPS338257
Increased population density and behavioural flexibility of African clawless otters (Aonyx capensis) in specific anthropogenic environments
Publisher: Springer Science and Business Media LLC
Date: 21-10-2020
Animal welfare and decision making in wildlife research
Publisher: Elsevier BV
Date: 09-2012
Recent prey capture experience and dynamic habitat quality mediate short-term foraging site fidelity in a seabird
Publisher: The Royal Society
Date: 25-07-2018
Abstract: Foraging site fidelity allows animals to increase their efficiency by returning to profitable feeding areas. However, the mechanisms underpinning why animals ‘stay’ or ‘switch’ sites have rarely been investigated. Here, we explore how habitat quality and prior prey capture experience influence short-term site fidelity by the little penguin ( Eudyptula minor ). Using 88 consecutive foraging trips by 20 brooding penguins, we found that site fidelity was higher after foraging trips where environmental conditions were favourable, and after trips where prey capture success was high. When penguins exhibited lower site fidelity, the number of prey captures relative to the previous trip increased, suggesting that switches in foraging location were an adaptive strategy in response to low prey capture rates. Penguins foraged closer to where other penguins foraged on the same day than they did to the location of their own previous foraging site, and caught more prey when they foraged close together. This suggests that penguins aggregated flexibly when prey was abundant and accessible. Our results illustrate how foraging predators can integrate information about prior experience with contemporary information such as social cues. This gives insight into how animals combine information adaptively to exploit changing prey distribution in a dynamic environment.
Cost-effective mitigation strategies to reduce bycatch threats to cetaceans identified using return-on-investment analysis
Publisher: Wiley
Date: 16-10-2020
DOI: 10.1111/COBI.13418
Abstract: Globally, fisheries bycatch threatens the survival of many whale and dolphin species. Strategies for reducing bycatch can be expensive. Management is inclined to prioritize investment in actions that are inexpensive, but these may not be the most effective. We used an economic tool, return-on-investment, to identify cost-effective measures to reduce cetacean bycatch in the trawl, net, and line fisheries of Australia. We examined 3 management actions: spatial closures, acoustic deterrents, and gear modifications. We compared an approach for which the primary goal was to reduce the cost of bycatch reduction to fisheries with an approach that aims solely to protect whale and dolphin species. Based on cost-effectiveness and at a fine spatial resolution, we identified the management strategies across Australia that most effectively abated dolphin and whale bycatch. Although trawl-net modifications were the cheapest strategy overall, there were many locations where spatial closures were the most cost-effective solution, despite their high costs to fisheries, due to their effectiveness in reducing all fisheries interactions. Our method can be used to delineate strategies to reduce bycatch threats to mobile marine species across erse fisheries at relevant spatial scales to improve conservation outcomes.
Influence of maternal mass and condition on energy transfer in Weddell seals
Publisher: Wiley
Date: 05-2006
The canid pest ejector challenge: controlling urban foxes while keeping domestic dogs safe
Publisher: CSIRO Publishing
Date: 24-03-2021
DOI: 10.1071/WR20078
Abstract: Abstract Context It is widely recognised that red foxes (Vulpes vulpes) are abundant within urban areas however, it is difficult to apply lethal control measures using poison baits in cities because of concerns about the safety of domestic pets, particularly dogs (Canis familiaris). Aims We tested canid pest ejectors (CPEs) as a potential method of fox control by measuring visitation and activation behaviour of foxes and other wildlife while assessing non-target risk to domestic dogs. Methods We compared eight urban and eight peri-urban sites in Sydney, with half of the sites having restricted access for domestic dogs. We allocated five camera traps and ejectors per site. Through generalised linear mixed models, we compared the probability of ejector activation between foxes and dogs. We also assessed the relationship between dog visitation and distance to habitation and dog restrictions as measures of dog safety. Key results Both species of canids were equally likely to pull the ejector (P = 0.26). As expected, dog visitation was significantly lower in sites with dog restrictions (P 0.001). However, it was not related to distance from habitation. Only two non-canid species were recorded pulling the ejector, suggesting high target-specificity for canids. Conclusions In sites with dog restrictions, the risk of dog casualties from CPEs is minimal. However, distance from habitation does not increase dog safety, at least within 250 m. The ejector is highly specific for canids. Implications We provide specific recommendations for the design of a potential fox control program using CPEs in urban and peri-urban areas. The ejector may be a safe method for fox control in cities when deployed at places without domestic dogs.
Forecasting intraspecific changes in distribution of a wide-ranging marine predator under climate change
Publisher: Springer Science and Business Media LLC
Date: 17-11-2021
DOI: 10.1007/S00442-021-05075-7
Abstract: Globally, marine animal distributions are shifting in response to a changing climate. These shifts are usually considered at the species level, but in iduals are likely to differ in how they respond to the changing conditions. Here, we investigate how movement behaviour and, therefore, redistribution, would differ by sex and maturation class in a wide-ranging marine predator. We tracked 115 tiger sharks ( Galeocerdo cuvier ) from 2002 to 2020 and forecast class-specific distributions through to 2030, including environmental factors and predicted occurrence of potential prey. Generalised Linear and Additive Models revealed that water temperature change, particularly at higher latitudes, was the factor most associated with shark movements. Females dispersed southwards during periods of warming temperatures, and while juvenile females preferred a narrow thermal range between 22 and 23 °C, adult female and juvenile male presence was correlated with either lower ( 22 °C) or higher ( 23 °C) temperatures. During La Niña, sharks moved towards higher latitudes and used shallower isobaths. Inclusion of predicted distribution of their putative prey significantly improved projections of suitable habitats for all shark classes, compared to simpler models using temperature alone. Tiger shark range off the east coast of Australia is predicted to extend ~ 3.5° south towards the east coast of Tasmania, particularly for juvenile males. Our framework highlights the importance of combining long-term movement data with multi-factor habitat projections to identify heterogeneity within species when predicting consequences of climate change. Recognising intraspecific variability will improve conservation and management strategies and help anticipate broader ecosystem consequences of species redistribution due to ocean warming.
A Comparative Analysis of SVM and IDNN for Identifying Penguin Activities
Publisher: Informa UK Limited
Date: 03-07-2017
Age and growth determination of three sympatric wobbegong sharks: How reliable is growth band periodicity in Orectolobidae?
Publisher: Elsevier BV
Date: 10-2013
Identifying technology solutions to bring conservation into the innovation era
Publisher: Wiley
Date: 02-10-2019
DOI: 10.1002/FEE.2111
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure
Publisher: Frontiers Media SA
Date: 24-09-2020
Animal welfare and conservation, the debate we must have: A response to Draper and Bekoff (2012)
Publisher: Elsevier BV
Date: 02-2013
The usefulness of DSM-III axis IV and axis V assessments
Publisher: American Psychiatric Association Publishing
Date: 07-1986
Abstract: DSM-III multiaxial diagnoses were given to 257 patients. Analysis of axis I diagnoses and axis IV and axis V assessments generally revealed the expected associations between particular psychiatric disorders and levels of psychosocial stress and social and occupational functioning. However, a major difficulty affecting the usefulness of axis IV and axis V data when they are routinely gathered according to the current DSM-III instructions is the stipulation that the clinician judge the etiological significance of a stressor before it is coded.
Low effective population size in the genetically bottlenecked Australian sea lion is insufficient to maintain genetic variation
Publisher: Wiley
Date: 07-04-2021
DOI: 10.1111/ACV.12688
Abstract: Genetic bottlenecks can reduce effective population sizes ( N e ), increase the rate at which genetic variation is lost via drift, increase the frequency of deleterious mutations and thereby accentuate inbreeding risk and lower evolutionary potential. Here, we tested for the presence of a genetic bottleneck in the endangered Australian sea lion ( Neophoca cinerea ), estimated N e and predicted future losses of genetic variation under a range of scenarios. We used 2238 genome‐wide neutral single‐nucleotide polymorphisms (SNPs) from 72 in iduals s led from colonies off the southern (SA) and western (WA) coastline of Australia. Coalescent analyses using approximate Bayesian computation (ABC) methods indicated that both the SA and WA populations have experienced a historical genetic bottleneck. Using LD‐based methods, we estimated contemporary N e to be 160 (CI = 146–178) and 424 (CI = 397–458) for the WA and SA populations respectively. Modelled future population declines suggested that disease epidemics prompted the highest increases in inbreeding relative to fishery‐related mortalities and other modelled threats. Small effective sizes and relatively low genetic variation leave this species vulnerable, and these risks may be compounded if current population declines are not reversed.
Will Whale Watchers Sacrifice Personal Experience to Minimize Harm to Whales?
Publisher: Cognizant, LLC
Date: 15-09-2014
DOI: 10.3727/154427314X14056884441662
Abstract: Humpback whale ( Megaptera novaeangliae ) watchers off Sydney, Australia were surveyed using stated preference techniques to investigate whether they were prepared to prioritize minimizing impact on whales over other factors of their whale-watching experience. Differences between shore- and boat-based whale watchers (343 and 1,133 participants, respectively) to hypothetical whale-watching situations were investigated. Both groups had a strong preference for minimizing impact on the animals. Boat-based whale watchers placed a slightly higher priority on receiving environmental education. Both groups expressed a preference for approaching closer to the whales than currently permitted (i.e., to 50 m), but the high levels of satisfaction of boat-based whale watchers suggest closer approach distances are not necessary to ensure a positive whale-watching experience.
Individual vocal identity in mother and pup Australian sea lions (Neophoca cinerea)
Publisher: Oxford University Press (OUP)
Date: 10-2006
Genetic divergence, speciation and biogeography of Mustelus (sharks) in the central Indo-Pacific and Australasia
Publisher: Elsevier BV
Date: 09-2012
DOI: 10.1016/J.YMPEV.2012.05.024
Abstract: The shark genus Mustelus is speciose, commercially important and systematically troublesome. We use a molecular approach combining inter and intra-specific data to investigate Mustelus species in the central Indo-Pacific and Australasia. Our analysis supports two Mustelus clades, one comprising species with no white spots and a placental reproductive mode and a second clade of white spotted, aplacental species. Levels of genetic ergence are low, especially among species in the white spotted, aplacental clade and this should be taken into account when employing molecular data to delineate species. Our data support the hypothesis of a radiation following dispersal from a northern hemisphere ancestor. Molecular dating suggests that localised speciation in Australasia may have occurred during the Pleistocene. We propose that some of the difficulties associated with Mustelus systematics relate to a recent radiation, particularly in the Australasian region.
Oceanographic conditions associated with white shark (Carcharodon carcharias) habitat use along eastern Australia
Publisher: Inter-Research Science Center
Date: 04-02-2021
DOI: 10.3354/MEPS13572
Abstract: Management of species with wide-ranging migrations is a complex issue, made more challenging when the species is both protected and poses a risk to humans. Understanding the oceanic conditions associated with shark habitat use can help develop mitigation strategies or warning systems that meet both conservation and human safety objectives. Using satellite tracks from 77 juvenile and sub-adult white sharks tagged over 10 yr, we modelled in idual movement patterns using hidden Markov models and applied generalised additive (mixed) models to explore correlations between movement patterns (presence-absence, habitat selection and behavioural state) and oceanographic and bathymetric variables. White sharks used the whole of the continental shelf, down to depths of 350 m on the continental slope. Sharks were present over a wide range of sea surface temperatures (SSTs 10-27°C), with the highest probability of occurring at ~20°C. However, the number of average daily tag positions was greatest when SST was between 14 and 18°C, and sharks were more likely to exhibit area-restricted movement when SST was between ~19 and 23°C. Sharks were more likely to be present and selected habitats in productive areas with moderate to high surface chl a concentrations as well as thermal and productivity fronts. Although mesoscale eddies did not influence the likelihood of in iduals being present in an area, there was a higher density of sharks in cold-core eddies compared to warm-core eddies. This study indicates that white shark presence and dispersal may be linked, perhaps via prey distribution, to oceanic conditions, potentially assisting development of suitable shark bite mitigation strategies.
Aligning tourist, industry and government expectations: A case study from the swim with whales industry in Tonga
Publisher: Elsevier BV
Date: 11-2010
A Call for International Leadership and Coordination to Realize the Potential of Conservation Technology
Publisher: Oxford University Press (OUP)
Date: 04-09-2019
Abstract: Advancing technology represents an unprecedented opportunity to enhance our capacity to conserve the Earth's bio ersity. However, this great potential is failing to materialize and rarely endures. We contend that unleashing the power of technology for conservation requires an internationally coordinated strategy that connects the conservation community and policy-makers with technologists. We argue an international conservation technology entity could (1) provide vision and leadership, (2) coordinate and deliver key services necessary to ensure translation from innovation to effective deployment and use of technology for on-the-ground conservation across the planet, and (3) help integrate innovation into bio ersity conservation policy from local to global scales, providing tools to monitor outcomes of conservation action and progress towards national and international bio ersity targets. This proposed entity could take the shape of an international alliance of conservation institutions or a formal intergovernmental institution. Active and targeted uptake of emerging technology can help society achieve bio ersity conservation goals.
Reliance of young sharks on threatened estuarine habitats for nutrition implies susceptibility to climate change
Publisher: Elsevier BV
Date: 05-2022
Seasonal oscillation in shore attendance and transience of New Zealand fur seals
Publisher: Canadian Science Publishing
Date: 10-1999
DOI: 10.1139/Z99-033
Abstract: The New Zealand fur seal (Arctocephalus forsteri) appears to show regular shore attendance in the form of seasonal oscillations. This phenomenon should be quantified to properly interpret counts of fur seals year old (i.e., non-pups). Here we test the predictability of peaks in the annual shore-attendance oscillation on Otago Peninsula using an autoregressive sine model and years of intensive survey data. We predicted that the peak in fur seal numbers ashore would lie between 14 January - 4 April (1996) and 8 January - 2 April (1997), although this low predictability is undesirable when attempts are made to monitor population trends. Estimating population size from counts of non-pups also requires knowledge of the rate of turnover of in iduals. Therefore, we tested the hypothesis that tagged animals from other colonies are immigrants to Otago Peninsula. With sightings on Otago Peninsula of fur seals tagged elsewhere in New Zealand, we used a Monte Carlo approach to simulate the expected frequency of single and multiple sightings of in iduals. We found that the observed frequency of multiple sightings was significantly less than predicted by the model (P 0.0001), indicating that tagged animals were transients. We also discovered that the sex ratio of tagged animals varied with breeding colony of origin (G 1 = 52.07, P 0.0001), suggesting that the impetus for emigration differs among colonies. We concur with the view that counting pups is the only way to estimate the relative abundance of New Zealand fur seals. In addition, we showed that counts of non-pups cannot be used to estimate population size because an unknown proportion of in iduals is transient. However, counting of pups does not address the issue of estimating relative abundance for locations with large numbers of nonbreeding in iduals and few or no breeders. With few or no pups it is impossible to estimate relative abundance using counts of pups.
Quantification of the maternal–embryonal nutritional relationship of elasmobranchs: case study of wobbegong sharks (genus Orectolobus)
Publisher: Wiley
Date: 06-04-2011
DOI: 10.1111/J.1095-8649.2011.02938.X
Abstract: The present study used wobbegong sharks (genus Orectolobus) to assess the threshold value proposed by previous research to categorize strict lecithotrophic from incipient histotrophic species. Totals of 236 and 135 ornate wobbegong Orectolobus ornatus and spotted wobbegong Orectolobus maculatus, respectively, were collected from the New South Wales commercial fishery between June 2003 and May 2006. Eight pregnant gulf wobbegong Orectolobus halei were also recorded outside the s ling period for the first time. The three species were reproductively synchronous with a gestation of c. 10-11 months. Embryos started to be macroscopically visible during January and external yolk sacs were fully absorbed by June to July when embryos were c. 200 mm total length (L(T) ). Internal yolk sacs were first observed during April to May when embryos were c. 160 mm L(T) , reached a peak during June and persisted in embryos immediately prior to parturition. The total wet mass from uterine egg to full-term embryos increased by 44-89% and 45-62%, whereas the total organic mass decreased by 32-33% and 26%, for O. ornatus and O. maculatus, respectively, suggesting that these species are strict lecithotrophic yolk-sac viviparous sharks with no maternal nutrient input. A review of the literature identified various issues and suggested that the previously proposed organic mass loss threshold value separating strict lecithotrophic species from incipient histotrophic species might not be appropriate. Instead, it is recommended that a combination of methods (e.g. estimation of organic mass gain or loss between ovarian egg and developed embryo, histology and electron microscopy of the uterus, radio-tracer assay and uterine fluid analysis throughout gestation) is used to discern between strict lecithotrophic and incipient histotrophic species.
Vocal recognition of mothers by Australian sea lion pups: individual signature and environmental constraints
Publisher: Elsevier BV
Date: 11-2009
Assessing the utility of two- and three-dimensional behavioural metrics in habitat usage models
Publisher: Inter-Research Science Center
Date: 29-05-2018
DOI: 10.3354/MEPS11947
Weddell seal behaviour during an exceptional oceanographic event in the Filchner-Ronne Ice Shelf in 2017
Publisher: Cambridge University Press (CUP)
Date: 12-04-2021
DOI: 10.1017/S0954102021000092
Abstract: Rapid and regionally contrasting climate changes have been observed around Antarctica. However, our understanding of the impact of these changes on ecosystems remains limited, and there is an urgent need to better identify habitats of Antarctic species. The Weddell seal ( Leptonychotes weddellii ) is a circumpolar mesopredator and an indicative species of Antarctic marine communities. It has been extensively studied in the western Ross Sea and East Antarctica, and an understanding of its ecology in the Weddell Sea in the wintertime is emerging. We documented the behavioural response(s) of four Weddell seals from February to June in 2017 in the Filchner-Ronne Ice Shelf region and related these to unusual oceanographic conditions in 2017. Unexpectedly, we found that Weddell seals had the longest foraging effort within the outflow of Ice Shelf Water or at its turbulent boundary. They also foraged on the eastern side of the trough from April to June within the Modified Warm Deep Water and seem to take advantage of the unusual conditions of persistent inflow of warm waters through the winter. Linking animal behavioural responses to oceanographic conditions is informative for quantifying rarely recorded events and provides great insight into how predators may respond to changing conditions.
Satellite derived offshore migratory movements of southern right whales (Eubalaena australis) from Australian and New Zealand wintering grounds
Publisher: Public Library of Science (PLoS)
Date: 07-05-2020
No evidence for recovery in the population of sperm whale bulls off Western Australia, 30 years post-whaling
Publisher: Inter-Research Science Center
Date: 09-04-2014
DOI: 10.3354/ESR00584
Tracking of marine predators to protect Southern Ocean ecosystems
Publisher: Springer Science and Business Media LLC
Date: 18-04-2020
Conservation of the critically endangered Eastern Australian Population of the Grey Nurse Shark (Carcharias taurus) through cross-jurisdictional management of a network of marine-protected areas
Publisher: Springer Science and Business Media LLC
Date: 09-11-2013
DOI: 10.1007/S00267-013-0174-X
Abstract: Between 2001 and 2009, 26 marine-protected areas (MPA) were established on the east Australian seaboard, at least in part, to manage human interactions with a critically endangered population of grey nurse shark, Carcharias taurus. This network is spread across six MPA systems and includes all 19 sites outlined in the National Recovery Plan for C. taurus, though five sites remain open to some forms of fishing. The reserve network has complex cross-jurisdictional management, as the sharks occur in waters controlled by the Australian states of New South Wales (NSW) and Queensland, as well as by the Commonwealth (Federal) government. Jurisdiction is further complicated by fisheries and conservation departments both engaging in management activities within each state. This has resulted in protected area types that include IUCN category II equivalent zones in NSW, Queensland, and Commonwealth marine parks that either overlay or complement another large scaled network of protected sites called critical habitats. Across the network, seven and eight rule permutations for ing and fishing, respectively, are applied to this population of sharks. Besides sites identified by the recovery plan, additional sites have been protected as part of the general development of MPA networks. A case study at one of these sites, which historically was known to be occupied by C. taurus but had been abandoned, appears to shows re-establishment of an aggregation of juvenile and sub-adult sharks. Concurrent with the re-establishment of the aggregation, a local e operator increased seasonal e visitation rates at the site fourfold. As a precautionary measure, protection of abandoned sites, which includes nursery and gestating female habitats are options that may assist recovery of the east coast population of C. taurus.
Alliance membership and kinship in wild male bottlenose dolphins ( Tursiops aduncus ) of southeastern Australia
Publisher: The Royal Society
Date: 22-09-2001
Putting the behavior into animal movement modeling: Improved activity budgets from use of ancillary tag information
Publisher: Wiley
Date: 20-10-2016
DOI: 10.1002/ECE3.2530
Population structure of adult female Australian sea lions is driven by fine-scale foraging site fidelity
Publisher: Elsevier BV
Date: 03-2012
Feast or famine: evidence for mixed capital--income breeding strategies in Weddell seals
Publisher: Springer Science and Business Media LLC
Date: 06-11-2008
Association patterns and kinship in female Indo-Pacific bottlenose dolphins (Tursiops aduncus) of southeastern Australia
Publisher: Springer Science and Business Media LLC
Date: 08-08-2006
Individual identity encoding and environmental constraints in vocal recognition of pups by Australian sea lion mothers
Publisher: Elsevier BV
Date: 03-2012
Seal mothers expend more on offspring under favourable conditions and less when resources are limited
Publisher: Wiley
Date: 12-01-2017
Abstract: In mammals, maternal expenditure on offspring is a complex mix of several factors including the species' mating system, offspring sex and the condition and age of the mother. While theory suggests that in polygynous species mothers should wean larger male offspring than females when resources and maternal conditions allow, the evidence for this remains equivocal. Southern elephant seals are highly dimorphic, polygynous capital breeders existing in an environment with highly variable resources and should therefore provide clear evidence to support the theoretical expectations of differential maternal expenditure in male and female pups. We quantified maternal size (mass and length) and pup size at birth and weaning for 342 elephant seal mothers at Macquarie Island. The study was conducted over 11 years of contrasting sea-ice and Southern Annular Mode values, both indices of maternal prey resources. Overall, large females weaned male pups that weighed 17 kg (15·5%) more than female pups. Maternal condition varied by as much as 59 kg among years, and was positively related to Southern Annular Mode, and negatively to maximum sea-ice extent. Smaller mothers weaned relatively larger male pups under favourable conditions, this effect was less apparent for larger mothers. We developed a simple model linking environmental variation to maternal masses post-partum, followed by maternal masses post-partum to weaning masses and then weaning masses to pup survival and demonstrated that environmental conditions affected predicted survival so that the pups of small mothers had an estimated 7% increase in first year survival in 'good' vs. 'bad' years compared to 1% for female pups of large mothers. Co-occurrence of environmental quality and conservative reproductive tactics suggests that mothers retain substantial plasticity in maternal care, enhancing their lifetime reproductive success by adjusting reproductive expenditure relative to both prevailing environmental conditions and their own capabilities.
Survivorship costs of play in the South American fur seal
Publisher: Elsevier BV
Date: 09-1991
Reply to ‘Clarifying the interpretation of Hamer et al. (2008) by Bilgmann et al. (2008)’
Publisher: Wiley
Date: 14-07-2009
Big data analyses reveal patterns and drivers of the movements of southern elephant seals
Publisher: Springer Science and Business Media LLC
Date: 08-03-2017
DOI: 10.1038/S41598-017-00165-0
Abstract: The growing number of large databases of animal tracking provides an opportunity for analyses of movement patterns at the scales of populations and even species. We used analytical approaches, developed to cope with “big data”, that require no ‘ a priori’ assumptions about the behaviour of the target agents, to analyse a pooled tracking dataset of 272 elephant seals ( Mirounga leonina ) in the Southern Ocean, that was comprised of ,000 location estimates collected over more than a decade. Our analyses showed that the displacements of these seals were described by a truncated power law distribution across several spatial and temporal scales, with a clear signature of directed movement. This pattern was evident when analysing the aggregated tracks despite a wide ersity of in idual trajectories. We also identified marine provinces that described the migratory and foraging habitats of these seals. Our analysis provides evidence for the presence of intrinsic drivers of movement, such as memory, that cannot be detected using common models of movement behaviour. These results highlight the potential for “big data” techniques to provide new insights into movement behaviour when applied to large datasets of animal tracking.
Predicting changes in distribution of a large coastal shark in the face of the strengthening east australian current
Publisher: Inter-Research Science Center
Date: 28-05-2020
DOI: 10.3354/MEPS13322
Abstract: In the face of accelerating climate change, conservation strategies will need to consider how marine animals deal with forecast environmental change as well as ongoing threats. We used 10 yr (2009-2018) of data from commercial fisheries and a bather protection program along the coast of New South Wales (NSW), southeastern Australia, to investigate (1) spatial and temporal patterns of occurrence in bull sharks and (2) environmental factors affecting bull shark occurrence along the coast of NSW. Predicted future distribution for this species was modelled for the forecast strengthening East Australian Current. Bull sharks were mostly harvested in small to larger estuaries, with average depth and rainfall responsible for contrasting patterns for each of the fisheries. There was an increase in the occurrence of bull sharks over the last decade, particularly among coastal setline fisheries, associated with seasonal availability of thermal gradients °C and both westward and southward coastal currents stronger than 0.15 and 0.60 m s -1 , respectively, during the austral summer. Our model predicts a 3 mo increase in the availability of favourable water temperatures along the entire coast of NSW for bull sharks by 2030. This coastline provides a uniquely favourable topography for range expansion in the face of a southerly shift of warmer waters, and habitat is unlikely to be a limiting factor for bull sharks in the future. Such a southerly shift in distribution has implications for the management of bull sharks both in commercial fisheries and for mitigation of shark-human interactions.
Multimodal mother–offspring recognition
Publisher: Elsevier BV
Date: 12-2018
Circumpolar habitat use in the southern elephant seal: implications for foraging success and population trajectories
Publisher: Wiley
Date: 05-2016
DOI: 10.1002/ECS2.1213
Shark conservation, governance and management: The sciencelaw disconnect
Publisher: Routledge
Date: 05-06-2014
Whale watching regulation compliance trends and the implications for management off Sydney, Australia
Publisher: Elsevier BV
Date: 11-2013
Warm Modified Circumpolar Deep Water Intrusions Drive Ice Shelf Melt and Inhibit Dense Shelf Water Formation in Vincennes Bay, East Antarctica
Publisher: American Geophysical Union (AGU)
Date: 30-07-2021
DOI: 10.1029/2020JC016998
Abstract: Antarctic Bottom Water (AABW) production supplies the deep limb of the global overturning circulation and ventilates the deep ocean. While the Weddell and Ross Seas are recognized as key sites for AABW production, additional sources have been discovered in coastal polynya regions around East Antarctica, most recently at Vincennes Bay. Vincennes Bay, despite encompassing two distinct polynya regions, is considered the weakest source, producing Dense Shelf Water (DSW) only just dense enough to contribute to the lighter density classes of AABW found offshore. Here we provide the first detailed oceanographic observations of the continental shelf in Vincennes Bay (104‐111°E), using CTD data from instrumented elephant seals spanning from February to November of 2012. We find that Vincennes Bay has East Antarctica’s warmest recorded intrusions of modified Circumpolar Deep Water (mCDW) and that warm mCDW drives basal melt under Vanderford and Underwood ice shelves. Our study also provides the first direct observational evidence for the inflow of meltwater to this region, which increases stratification and hinders DSW formation, and thus AABW production. The Vincennes Bay glaciers, together with the Totten Glacier, drain part of the Aurora Basin, which holds up to 7 m of sea level rise equivalent. Our results highlight the vulnerability of the East Antarctic Ice Sheet to intrusions of mCDW.
Ghosts in the data: false detections in VEMCO pulse position modulation acoustic telemetry monitoring equipment
Publisher: Springer Science and Business Media LLC
Date: 12-2015
Delayed onset of vocal recognition in Australian sea lion pups (Neophoca cinerea)
Publisher: Springer Science and Business Media LLC
Date: 06-05-2009
DOI: 10.1007/S00114-009-0546-5
Abstract: In pinnipeds, maternal care strategies and colony density may influence a species' in idual recognition system. We examined the onset of vocal recognition of mothers by Australian sea lion pups (Neophoca cinerea). At 2 months of age, pups responded significantly more to the calls of their own mothers than alien female calls demonstrating a finely tuned recognition system. However, newborn pups did not respond differentially to the calls of their mother from alien female calls suggesting that vocal recognition had not yet developed or is not yet expressed. These findings are in stark contrast to other otariid species where pups learn their mother's voice before their first separation. Variance in colony density, pup movements, and natal site fidelity may have reduced selective pressures on call recognition in young sea lions, or alternatively, another sensory system may be used for recognition in the early stage of life.
The diet of greater crested terns off southeast Australia varies with breeding stage and sea surface temperature
Publisher: Springer Science and Business Media LLC
Date: 18-08-2021
DOI: 10.1007/S00227-021-03947-3
Abstract: Monitoring seabird diet can provide insights into marine ecosystems that are logistically difficult or costly to observe with traditional fisheries survey methods. Using digital photography, we described the diet of greater crested terns ( Thalasseus bergii ) breeding on Montague Island (36°15′ S, 150°13′ E), a colony located in an oceanographically dynamic region of southeast Australia. We investigated how the type and size of prey brought back to the colony changed in relation to both breeding stage and variation in local environmental conditions. 2469 prey items were identified to species or family level over 35 consecutive days of photo-s ling in 2018. Australian anchovy ( Engraulis australis ), a surface-schooling clupeid fish, was the most abundant prey returned to the colony during all breeding stages (84.5%). The proportion of anchovy increased from 77.0% when birds were provisioning their adult partners during incubation, to 92.4% when they were provisioning chicks, suggesting selective foraging behaviour on this energy-rich species to facilitate rapid chick growth. Anchovy size was significantly larger during incubation (91.1 ± 14.9 mm), smaller during early chick provisioning (71.8 ± 11.0 mm), and increased slightly during mid provisioning (79.6 ± 11.9 mm), indicating adaptive prey selection that is matched to the physical requirements of different breeding stages. The proportion of anchovy prey was also influenced by sea surface temperature (SST), with anchovy becoming more dominant with increasing local SSTs, up to ~ 17.5 °C. This study gives new insight into the types of prey that are seasonally available to predators in this region. The strong specialisation by greater crested terns for one energy-rich species of schooling fish (anchovy) suggests that variation in the size and composition of their prey may serve as an indicator of change in the pelagic ecosystem off southeast Australia.
Impacts of climate change on Australian marine mammals
Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/ZO12131
Abstract: Increasing evidence suggests that climate change is negatively affecting marine ecosystems and biota. However, little is known of how climate change will impact marine mammals. This review aims to identify the effects of climatic variations on Australian marine mammals and determine their potential responses to climate change. Shifts in distributions and reproductive success have been associated with climatic factors, while stranding events, drowning of seal pups, exposure to altered water conditions and disease in several marine mammal species have followed extreme weather events. Climate change may produce distributional shifts as the ranges of warm-water species expand or shift southwards, and those of cold-water species contract. Reductions in the extent of key habitats, changes in breeding success, a greater incidence of strandings in dugongs and cetaceans, and increased exposure of coastal species to pollutants and pathogens are likely. The capacity of Australian marine mammals to adapt to climate change is poorly understood, though there is evidence that several species may be able to modify their physiology or behaviour in response to warming temperatures. To increase the resilience of marine mammals, it is necessary to address non-climatic threats, such as ensuring that key habitats are protected in Australia.
Vocal Discrimination in Mate Guarding Male Australian Sea Lions: Familiarity Breeds Contempt
Publisher: Wiley
Date: 05-2010
Estimating survival and capture probability of fur seal pups using multistate mark-recapture models
Publisher: Oxford University Press (OUP)
Date: 02-2003
Application of the Acoustic Propagation Model to a deep‐water cross‐shelf curtain
Publisher: Wiley
Date: 08-06-2017
A “wicked problem” reconciling human-shark conflict, shark bite mitigation, and threatened species
Publisher: Frontiers Media SA
Date: 20-10-2021
DOI: 10.3389/FCOSC.2021.720741
Abstract: Conservation measures often result in a “wicked problem,” i.e., a complex problem with conflicting aims and no clear or straightforward resolution without severe adverse effects on one or more parties. Here we discuss a novel approach to an ongoing problem, in which actions to reduce risk to humans, involve lethal control of otherwise protected species. To protect water users, nets are often used to catch potentially dangerous sharks at popular bathing beaches, yet in Australian waters one of the targeted species, the white shark ( Carcharodon carcharias ) is listed as Vulnerable, while bycatch includes the Critically Endangered grey nurse shark ( Carcharias taurus ). Recent, highly publicised, shark attacks have triggered demands for improved bather protection, whilst welfare and conservation organisations have called for removal of lethal measures. This leaves management and policy makers with a wicked problem: removing nets to reduce impacts on threatened species may increase risk to humans or leaving the program as it is on the premise that the benefits provided by bather protection are greater than the impact on threatened and protected species. We used multivariate analysis and generalised additive models to investigate the biological, spatial-temporal, and environmental patterns influencing catch rates of threatened and of potentially dangerous shark species in the New South Wales shark nets over two decades to April 2019. Factors influencing catches were used to develop a matrix of potential changes to reduce catch of threatened species. Our proposed solutions include replacing existing nets with alternative mitigation strategies at key beaches where catch rate of threatened species is high. This approach provides stakeholders with a hierarchy of scenarios that address both social demands and threatened species conservation and is broadly applicable to human-wildlife conflict scenarios elsewhere.
Decadal changes in blood δ 13 C values, at-sea distribution, and weaning mass of southern elephant seals from Kerguelen Islands
Publisher: The Royal Society
Date: 19-08-2020
Abstract: Changes in the foraging environment and at-sea distribution of southern elephant seals from Kerguelen Islands were investigated over a decade (2004–2018) using tracking, weaning mass, and blood δ 13 C values. Females showed either a sub-Antarctic or an Antarctic foraging strategy, and no significant shift in their at-sea distribution was detected between 2004 and 2017. The proportion of females foraging in sub-Antarctic versus Antarctic habitats did not change over the 2006–2018 period. Pup weaning mass varied according to the foraging habitat of their mothers. The weaning mass of sub-Antarctic foraging mothers' pups decreased by 11.7 kg over the study period, but they were on average 5.8 kg heavier than pups from Antarctic foraging mothers. Pup blood δ 13 C values decreased by 1.1‰ over the study period regardless of their sex and the presumed foraging habitat of their mothers. Together, these results suggest an ecological change is occurring within the Indian sector of the Southern Ocean with possible consequences on the foraging performance of southern elephant seals. We hypothesize that this shift in δ 13 C is related to a change in primary production and/or in the composition of phytoplankton communities, but this requires further multidisciplinary investigations.
Risk factors associated with bruising in red deer at a commercial slaughter plant
Publisher: Elsevier BV
Date: 11-1996
DOI: 10.1016/S0309-1740(96)00017-4
Abstract: Bruising of slaughter animals has both economic and welfare implications. In order to identify potential risk factors we surveyed bruising of red deer carcasses from a single Deer Slaughter Plant (DSP) over a three year period. Downgrading due to bruising did not vary between the three years surveyed [1991, n = 21 454, 6.5% downgraded (dg) 1992, n = 22 289, 7.9% dg 1993, n = 22 262, 6.1% dg]. From an intensive examination of one year's kill (1991) we related the incidence of bruising to various preslaughter transport, seasonal and animal variables. Bruising varied significantly with time of year, hot carcass weight, distance transported, carrier company and carcass fatness. Bruising was related to duration of lairage for some periods of the year which varied with sex. The majority of bruising was on one or other hindquarter implying a consistent cause of the damage. Carcass quality and deer welfare can be best protected by careful driving, by only transporting animals in good condition and avoiding transporting males during the rut.
The importance of sample size in marine megafauna tagging studies
Publisher: Wiley
Date: 16-07-2019
DOI: 10.1002/EAP.1947
Abstract: Telemetry is a key, widely used tool to understand marine megafauna distribution, habitat use, behavior, and physiology however, a critical question remains: "How many animals should be tracked to acquire meaningful data sets?" This question has wide-ranging implications including considerations of statistical power, animal ethics, logistics, and cost. While power analyses can inform s le sizes needed for statistical significance, they require some initial data inputs that are often unavailable. To inform the planning of telemetry and biologging studies of marine megafauna where few or no data are available or where resources are limited, we reviewed the types of information that have been obtained in previously published studies using different s le sizes. We considered s le sizes from one to >100 in iduals and synthesized empirical findings, detailing the information that can be gathered with increasing s le sizes. We complement this review with simulations, using real data, to show the impact of s le size when trying to address various research questions in movement ecology of marine megafauna. We also highlight the value of collaborative, synthetic studies to enhance s le sizes and broaden the range, scale, and scope of questions that can be answered.
Continental‐scale acoustic telemetry and network analysis reveal new insights into stock structure
Publisher: Wiley
Date: 05-05-2021
DOI: 10.1111/FAF.12565
Abstract: Delineation of population structure (i.e. stocks) is crucial to successfully manage exploited species and to address conservation concerns for threatened species. Fish migration and associated movements are key mechanisms through which discrete populations mix and are thus important determinants of population structure. Detailed information on fish migration and movements is becoming more accessible through advances in telemetry and analysis methods however such information is not yet used systematically in stock structure assessment. Here, we described how detections of acoustically tagged fish across a continental‐scale array of underwater acoustic receivers were used to assess stock structure and connectivity in seven teleost and seven shark species and compared to findings from genetic and conventional tagging. Network analysis revealed previously unknown population connections in some species, and in others bolstered support for existing stock discrimination by identifying nodes and routes important for connectivity. Species with less variability in their movements required smaller s le sizes (45–50 in iduals) to reveal useful stock structure information. Our study shows the power of continental‐scale acoustic telemetry networks to detect movements among fishery jurisdictions. We highlight methodological issues that need to be considered in the design of acoustic telemetry studies for investigating stock structure and the interpretation of the resulting data. The advent of broad‐scale acoustic telemetry networks across the globe provides new avenues to understand how movement informs population structure and can lead to improved management.
Summer foraging by lactating female New Zealand fur seals (Arctocephalus forsteri) off Otago Peninsula, New Zealand
Publisher: Canadian Science Publishing
Date: 04-1995
DOI: 10.1139/Z95-080
Abstract: The behaviour of female New Zealand fur seals (Arctocephalus forsteri) at sea and on land at the rookery of Fuchsia Gully, Otago Peninsula, New Zealand (45 °52′S, 170 °44′E), was examined during the early stages of lactation in the 1993 – 1994 breeding season. The attendance patterns of 19 females were investigated using daily observation at the rookery. Trips to sea to forage ranged from 3.4 h up to 8 days (mean 3.26 ± 1.1 days), and attendance periods at the rookery ranged from 1 to 13 days (mean 3.09 ± 1.63 days). At sea, the behaviour of four females was examined by deploying time–depth recorders. Females showed a nocturnal pattern of ing, 88.8–97.3% of es being made during the hours of darkness. For all females and each night of foraging, the deepest es were completed around dawn and dusk. The deepest e recorded was 163 m and all females dove over 100 m deep on at least one e. The overall median e depth was considerably less than this, as around 24:00–03:00, females undertook many shallow es, and during this time the median e depth ranged from 5 to 10 m for the four females. Dives occurred in bouts, but bout duration varied significantly with time of day. Bouts were short during the day and longer at night, 55% of night bouts lasting throughout the night. Maximum e durations ranged from 3.17 to 6.17 min and mean e durations from 0.67 to 1.18 min for in idual females. Dive depth was significantly related to e duration for all four females. Two of the females also carried satellite transmitters, and at sea location was determined on three separate nights of foraging. Females were found to be foraging up to 78 km from the rookery, but always over the continental shelf (in water shallower than the 200 m depth contour).
Important marine habitat off east Antarctica revealed by two decades of multi-species predator tracking
Publisher: Wiley
Date: 14-07-2015
DOI: 10.1111/ECOG.01021
Testing a key assumption of wildlife buffer zones: is flight initiation distance a species-specific trait?
Publisher: Elsevier BV
Date: 03-2003
The suppression of Antarctic bottom water formation by melting ice shelves in Prydz Bay
Publisher: Springer Science and Business Media LLC
Date: 23-08-2016
DOI: 10.1038/NCOMMS12577
Abstract: A fourth production region for the globally important Antarctic bottom water has been attributed to dense shelf water formation in the Cape Darnley Polynya, adjoining Prydz Bay in East Antarctica. Here we show new observations from CTD-instrumented elephant seals in 2011–2013 that provide the first complete assessment of dense shelf water formation in Prydz Bay. After a complex evolution involving opposing contributions from three polynyas (positive) and two ice shelves (negative), dense shelf water (salinity 34.65–34.7) is exported through Prydz Channel. This provides a distinct, relatively fresh contribution to Cape Darnley bottom water. Elsewhere, dense water formation is hindered by the freshwater input from the Amery and West Ice Shelves into the Prydz Bay Gyre. This study highlights the susceptibility of Antarctic bottom water to increased freshwater input from the enhanced melting of ice shelves, and ultimately the potential collapse of Antarctic bottom water formation in a warming climate.
Seasonal Meandering of the Polar Front Upstream of the Kerguelen Plateau
Publisher: American Geophysical Union (AGU)
Date: 25-09-2018
DOI: 10.1029/2018GL079614
Abstract: The location of the Antarctic Polar Front (PF) is mapped in the Southern Indian Ocean by decomposing the shape of temperature and salinity profiles into vertical modes using a functional Principal Component Analysis. We define the PF as the northernmost minimum of temperature at the subsurface and represent it as a linear combination of the first three modes. This method is applied on an ocean reanalysis data set and on in situ observations, revealing a seasonal variability of the PF latitudinal position that is most pronounced between the Conrad Rise and the Kerguelen Plateau. This shift coincides with variations in the transport across the Northern Kerguelen Plateau. We suggest that seasonal changes of the upper stratification may drive the observed variability of the PF, with potentially large implications for the pathways and residence time of water masses over the plateau and the phytoplankton bloom extending southeast of the Kerguelen Islands.
Coastal seascape variability in the intensifying East Australian Current Southern Extension
Publisher: Frontiers Media SA
Date: 21-09-2022
DOI: 10.3389/FMARS.2022.925123
Abstract: Coastal pelagic ecosystems are highly variable in space and time, with environmental conditions and the distribution of biomass being driven by complex processes operating at multiple scales. The emergent properties of these processes and their interactive effects result in complex and dynamic environmental mosaics referred to as “seascapes”. Mechanisms that link large-scale oceanographic processes and ecological variability in coastal environments remain poorly understood, despite their importance for predicting how ecosystems will respond to climate change. Here we assessed seascape variability along the path of the rapidly intensifying East Australian Current (EAC) Southern Extension in southeast Australia, a hotspot of ocean warming and ecosystem tropicalisation. Using satellite and in situ measures of temperature, salinity and current velocity coupled with contemporaneous measurements of pelagic biomass distribution from nine boat-based active acoustic surveys in five consecutive years, we investigated relationships between the physical environment and the distribution of pelagic biomass (zooplankton and fish) at multiple timescales. Survey periods were characterised by high variability in oceanographic conditions, with variation in coastal conditions influenced by meso-to-large scale processes occurring offshore, including the position and strength of eddies. Intra-annual variability was often of a similar or greater magnitude to inter-annual variability, suggesting highly dynamic conditions with important variation occurring at scales of days to weeks. Two seascape categories were identified being characterised by (A) warmer, less saline water and (B) cooler, more saline water, with the former indicating greater influence of the EAC on coastal processes. Warmer waters were also associated with fewer, deeper and less dense biological aggregations. As the EAC continues to warm and penetrate further south, it is likely that this will have substantial effects on biological activity in coastal pelagic ecosystems, including a potential reduction in the accessibility of prey aggregations to surface-feeding predators and to fisheries. These results highlight the import role of offshore oceanographic processes in driving coastal seascape variability and biological activity in a region undergoing rapid oceanic warming and ecological change.
Long-term trends and a risk analysis of cetacean entanglements and bycatch in fisheries gear in Australian waters
Publisher: Springer Science and Business Media LLC
Date: 19-11-2020
Giardia duodenalis and Cryptosporidium occurrence in Australian sea lions (Neophoca cinerea) exposed to varied levels of human interaction
Publisher: Elsevier BV
Date: 12-2014
Dynamics of marine predators off an oceanic island and implications for management of a preventative shark fishing program
Publisher: Springer Science and Business Media LLC
Date: 04-03-2021
Estimating the rate of quasi-extinction of the Australian grey nurse shark (Carcharias taurus) population using deterministic age-and stage-classified models
Publisher: Elsevier BV
Date: 10-2004
Cuttlefish perform multiple agonistic displays to communicate a hierarchy of threats
Publisher: Springer Science and Business Media LLC
Date: 27-07-2016
The Limits of Dispersal: Fine Scale Spatial Genetic Structure in Australian Sea Lions
Publisher: Frontiers Media SA
Date: 03-05-2016
Finding mesopelagic prey in a changing Southern Ocean
Publisher: Springer Science and Business Media LLC
Date: 12-12-2019
DOI: 10.1038/S41598-019-55152-4
Abstract: Mesopelagic fish and squid occupy ocean depths extending below the photic zone and their vertical migrations represent a massive pathway moving energy and carbon through the water column. Their spatio-temporal distribution is however, difficult to map across remote regions particularly the vast Southern Ocean. This represents a key gap in understanding biogeochemical processes, marine ecosystem structure, and how changing ocean conditions will affect marine predators, which depend upon mesopelagic prey. We infer mesopelagic prey vertical distribution and relative abundance in the Indian sector of the Southern Ocean (20° to 130°E) with a novel approach using predator-derived indices. Fourteen years of southern elephant seal tracking and e data, from the open ocean between the Antarctic Polar Front and the southern Antarctic Circumpolar Current front, clearly show that the vertical distribution of mesopelagic prey is influenced by the physical hydrographic processes that structure their habitat. Mesopelagic prey have a more restricted vertical migration and higher relative abundance closer to the surface where Circumpolar Deep Water rises to shallower depths. Combining these observations with a future projection of Southern Ocean conditions we show that changes in the coupling of surface and deep waters will potentially redistribute mesopelagic prey. These changes are small overall, but show important spatial variability: prey will increase in relative abundance to the east of the Kerguelen Plateau but decrease to the west. The consequences for deep- ing specialists such as elephant seals and whales over this time scale will likely be minor, but the changes in mesoscale vertical energy flow have implications for predators that forage within the mesopelagic zone as well as the broader pelagic ecosystem.
Refined Shortest Paths (RSP): Incorporation of topography in space use estimation from node‐based telemetry data
Publisher: Wiley
Date: 29-09-2020
The Development of Play in the South American Fur Seal
Publisher: Wiley
Date: 12-01-1991
Are Speed Restriction Zones an effective management tool for minimising impacts of boats on dolphins in an Australian marine park?
Publisher: Elsevier BV
Date: 2012
Visual cues do not enhance sea lion pups' response to multimodal maternal cues
Publisher: Springer Science and Business Media LLC
Date: 29-06-2018
DOI: 10.1038/S41598-018-28171-W
Abstract: Mammals use multiple sensory cues for mother-offspring recognition. While the role of single sensory cues has been well studied, we lack information about how multiple cues produced by mothers are integrated by their offspring. Knowing that Australian sea lion ( Neophoca cinerea ) pups recognise their mother’s calls, we first tested whether visual cues are used by pups to discriminate between conspecifics of different age classes (adult female vs pup). We then examined if adding a visual stimulus to an acoustic cue enhances vocal responsiveness of Australian sea lion pups, by presenting wild in iduals with either a visual cue (female 3D-model), an acoustic cue (mother’s call), or both simultaneously, and observing their reaction. We showed that visual cues can be used by pups to distinguish adult females from other in iduals, however we found no enhancement effect of these cues on the response in a multimodal scenario. Audio-only cues prompted a similar reaction to audio-visual cues that was significantly stronger than pup response to visual-only cues. Our results suggest that visual cues are dominated by acoustic cues and that pups rely on the latter in mother recognition.
Protected area use by two sympatric marine predators repopulating their historical range
Publisher: Inter-Research Science Center
Date: 07-2021
DOI: 10.3354/ESR01129
Abstract: As large carnivores recover from over-exploitation, managers often lack evidence-based information on species habitat requirements and the efficacy of management practices, particularly where species repopulate areas from which they have long been extirpated. We investigated the movement and habitat use by 2 semi-aquatic carnivores (Australian fur seals Arctocephalus pusillus doriferus and New Zealand fur seals A. forsteri ) at the northern end of their distributions in Australia, where after a long absence both are recolonising their historic range. We also assessed male fur seal habitat use overlap with terrestrial and marine protected areas (PAs). While at the margin of the range during winter and early spring, the males remained inshore close to terrestrial sites and where interactions with humans often occur. From early spring, the males from the range margin showed uniform movement toward colonies in the core of the species’ range prior to their breeding seasons. This contrasts with males tracked from the core of the species’ range that returned periodically to colonies during the year, and highlights the importance of range-wide monitoring of a species to inform conservation planning. Habitat use by some males included over 90% of a marine PA at the margin of the species’ range. Most terrestrial haul-outs used were within terrestrial PAs, while sites not protected were on the margin of the range. Despite wide-ranging habits, their dependence on coastal sites, where human access and activities can be regulated and more readily enforced, suggests that terrestrial and marine PAs will continue to play an important role in managing the recovery of these fur seals.
Extreme Effects of Extreme Disturbances: A Simulation Approach to Assess Population Specific Responses
Publisher: Frontiers Media SA
Date: 06-10-2020
Common dolphins subject to fisheries impacts in Southern Australia are genetically differentiated: implications for conservation
Publisher: Wiley
Date: 12-2008
Quality measurement and surveillance platforms in critically ill children: A scoping review.
Publisher: Elsevier BV
Date: 07-2022
DOI: 10.1016/J.AUCC.2022.07.006
Abstract: The objective of this study was to describe current surveillance platforms which support routine quality measurement in paediatric critical care. Scoping review. The search strategy consisted of a traditional database and grey literature search as well as expert consultation. Surveillance platforms were eligible for inclusion if they collected measures of quality in critically ill children. The search strategy identified 21 surveillance platforms, collecting 57 unique outcome (70%), process (23%), and structural (7%) quality measures. Hospital-associated infections were the most commonly collected outcome measure across all platforms (n = 11 52%). In general, case definitions were not harmonised across platforms, with the exception of nationally mandated hospital-associated infections (e.g., central line-associated blood stream infection). Data collection relied on manual coding. Platforms typically did not provide an evidence-based rationale for measures collected, with no identifiable reports of co-designed, consensus-derived measures or consumer involvement in measure selection or prioritisation. Quality measurement in critically ill children lacks uniformity in definition which limits local and international benchmarking. Current surveillance activities for critically ill children focus heavily on outcome measurement, with process, structural, and patient-reported measures largely overlooked. Long-term outcome measures were not routinely collected. Harmonisation of paediatric intensive care unit quality measures is needed and can be achieved using prioritisation and consensus/co-design methods.
The influence of behavioural context on Weddell seal (Leptonychotes weddellii) airborne mother-pup vocalisation
Publisher: Elsevier BV
Date: 07-2011
DOI: 10.1016/J.BEPROC.2011.06.005
Abstract: Previous mammalian studies have demonstrated that varying levels of signaller arousal are frequently expressed through vocal behaviour. The potential for callers to convey their motivational state may ensure that recipient responses are appropriate to their needs. The current study investigated the influence of behavioural context on Weddell seal mother-pup vocalisation. Mother and pup call rates were calculated within five and seven behavioural contexts, respectively, and the acoustic characteristics of 69 pup calls were measured within four contexts (total calls = 276). Context significantly influenced the temporal patterning of calls, with reuniting mothers and pups and lone active pups emitting more calls than during mother-pup contact periods. Reuniting and lone pup calls were also characterised by longer durations, higher fundamental frequencies, and increased energy in upper harmonics. Results suggest that reunion events and lone pup searching are characterised by calls reflective of heightened arousal, compared with mother-pup contact periods.
Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species
Publisher: Springer Science and Business Media LLC
Date: 03-05-2018
Consequences of global shipping traffic for marine giants
Publisher: Wiley
Date: 05-12-2018
DOI: 10.1002/FEE.1987
Pelagic and benthic ecosystems drive differences in population and individual specializations in marine predators
Publisher: Springer Science and Business Media LLC
Date: 26-06-2021
Distance does matter: close approaches by boats impede feeding and resting behaviour of Indo-Pacific bottlenose dolphins
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/WR11048
Abstract: Context Potential impacts of human disturbance on animal populations can be measured as behavioural responses and may affect the survival and fecundity of animals. In areas where human–wildlife interactions occur, conservation management needs to be in place to secure both a viable tourism industry and the sustainability of the targeted species. Aims We sought to evaluate whether different approach distances by boat have effects on the behaviour and group cohesion of dolphins that are targeted by Australia’s largest dolphin-watching industry. Methods The effects of different approach distances of boats on the behavioural states of dolphins, group dispersal and direction of movement were investigated in this area by controlled boat experiments conducted between August 2008 and December 2009. Key results Results showed that there was significantly less feeding when boats approached dolphin groups to a distance of 50 m than when they did to a distance of 150 m, or with controlled approaches. Resting was also observed significantly less when boats approached to a distance of 50 m than when they approached to a distance of 150 m. The dispersal of dolphin groups was significantly tighter (less dispersed) when boats approached to 50 m than that with 150-m-distance or controlled approaches. Furthermore, the dolphins’ direction of movement was less neutral when the experimental boat approaches were carried out at a distance of 50 m than when they were carried out at a distance of 150 m, or with controlled approaches. Similar results were also obtained for dolphin groups including calves. Conclusions On the basis of the results from this study, we recommend that the existing New South Wales regulations, which stipulate that dolphin-watching boats keep a distance of 50 m to groups with adults only and 150 m to groups with calves, are maintained within the Port Stephens–Great Lakes Marine Park (PSGLMP). Implications Management plans whose stated goals include both sustainability of a dolphin-watching industry and longer-term viability of a dolphin population may reconcile conflicting objectives and improve their decision making by using these empirical measures rather than best guesses.
Dolphins and Boats: When Is a Disturbance, Disturbing?
Publisher: Frontiers Media SA
Date: 26-05-2020
Publish or perish: why it’s important to publicise how, and if, research activities affect animals
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/WR12014
Abstract: Wildlife researchers and conservation biologists are encountering growing research difficulties due to strong and effective advocacy of animal welfare concerns. However, collecting information on the basic biology of animals, which is often essential to effective conservation and management, frequently involves invasive research. The latter is unacceptable to some animal welfare advocates, even if it ultimately leads to better conservation outcomes. For effective bio ersity conservation it is imperative that conservation and wildlife researchers lucidly present the case for their research on in idual animals. This requires conservation biologists and the research community in general, to present these arguments in the public domain as well as in peer-reviewed literature. Moreover, it is important to measure how these activities affect animals. Only then can we show that high quality research activities often have little or no effects on animal vital rates and performance.
The retrospective analysis of Antarctic tracking data project
Publisher: Springer Science and Business Media LLC
Date: 18-03-2020
DOI: 10.1038/S41597-020-0406-X
Abstract: The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Bio ersity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets and accompanying syntheses provide a greater understanding of fundamental ecosystem processes in the Southern Ocean, support modelling of predator distributions under future climate scenarios and create inputs that can be incorporated into decision making processes by management authorities. In this data paper, we present the compiled tracking data from research groups that have worked in the Antarctic since the 1990s. The data are publicly available through bio ersity.aq and the Ocean Biogeographic Information System. The archive includes tracking data from over 70 contributors across 12 national Antarctic programs, and includes data from 17 predator species, 4060 in idual animals, and over 2.9 million observed locations.
Regional variation in winter foraging strategies by Weddell seals in eastern Antarctica and the Ross Sea
Publisher: Frontiers Media SA
Date: 22-09-2021
DOI: 10.3389/FMARS.2021.720335
Abstract: The relative importance of intrinsic and extrinsic determinants of animal foraging is often difficult to quantify. The most southerly breeding mammal, the Weddell seal, remains in the Antarctic pack-ice year-round. We compared Weddell seals tagged at three geographically and hydrographically distinct locations in East Antarctica (Prydz Bay, Terre Adélie , and the Ross Sea) to quantify the role of in idual variability and habitat structure in winter foraging behaviour. Most Weddell seals remained in relatively small areas close to the coast throughout the winter, but some dispersed widely. In idual utilisation distributions ( UDi , a measure of the total area used by an in idual seal) ranged from 125 to 20,825 km 2 . This variability was not due to size or sex but may be due to other intrinsic states for ex le reproductive condition or personality. The type of foraging (benthic vs. pelagic) varied from 56.6 ± 14.9% benthic es in Prydz Bay through 42.1 ± 9.4% Terre Adélie to only 25.1 ± 8.7% in the Ross Sea reflecting regional hydrographic structure. The probability of benthic ing was less likely the deeper the ocean. Ocean topography was also influential at the population level seals from Terre Adélie , with its relatively narrow continental shelf, had a core (50%) UD of only 200 km 2 , considerably smaller than the Ross Sea (1650 km 2 ) and Prydz Bay (1700 km 2 ). Sea ice concentration had little influence on the time the seals spent in shallow coastal waters, but in deeper offshore water they used areas of higher ice concentration. Marine Protected Areas (MPAs) in the Ross Sea encompass all the observed Weddell seal habitat, and future MPAs that include the Antarctic continental shelf are likely to effectively protect key Weddell seal habitat.
Mother–pup recognition mechanisms in Australia sea lion (Neophoca cinerea) using uni- and multi-modal approaches
Publisher: Springer Science and Business Media LLC
Date: 16-06-2022
DOI: 10.1007/S10071-022-01641-5
Abstract: Communication is the process by which one emitter conveys information to one or several receivers to induce a response (behavioral or physiological) by the receiver. Communication plays a major role in various biological functions and may involve signals and cues from different sensory modalities. Traditionally, investigations of animal communication focused on a single sensory modality, yet communication is often multimodal. As these different processes may be quite complex and therefore difficult to disentangle, one approach is to first study each sensorial modality separately. With this refined understanding of in idual senses, revealing how they interact becomes possible as the characteristics and properties of each modality can be accounted for, making a multimodal approach feasible. Using this framework, researchers undertook systematic, experimental investigations on mother-pup recognition processes in a colonial pinniped species, the Australian sea lion Neophoca cinerea. The research first assessed the abilities of mothers and pups to identify each other by their voice using playback experiments. Second, they assessed whether visual cues are used by both mothers and pups to distinguish them from conspecifics, and/or whether females discriminate the odor of their filial pup from those from non-filial pups. Finally, to understand if the information transmitted by different sensory modalities is analyzed synergistically or if there is a hierarchy among the sensory modalities, experiments were performed involving different sensory cues simultaneously. These findings are discussed with regards to the active space of each sensory cue, and of the potential enhancements that may arise by assessing information from different modalities.
Creatures of habit: Foraging habitat fidelity of adult female Australian sea lions
Publisher: Inter-Research Science Center
Date: 20-12-2011
DOI: 10.3354/MEPS09392
Cultural traditions across a migratory network shape the genetic structure of southern right whales around Australia and New Zealand
Publisher: Springer Science and Business Media LLC
Date: 09-11-2015
DOI: 10.1038/SREP16182
Abstract: Fidelity to migratory destinations is an important driver of connectivity in marine and avian species. Here we assess the role of maternally directed learning of migratory habitats, or migratory culture, on the population structure of the endangered Australian and New Zealand southern right whale. Using DNA profiles, comprising mitochondrial DNA (mtDNA) haplotypes (500 bp), microsatellite genotypes (17 loci) and sex from 128 in idually-identified whales, we find significant differentiation among winter calving grounds based on both mtDNA haplotype (F ST = 0.048, Φ ST = 0.109, p 0.01) and microsatellite allele frequencies (F ST = 0.008, p 0.01), consistent with long-term fidelity to calving areas. However, most genetic comparisons of calving grounds and migratory corridors were not significant, supporting the idea that whales from different calving grounds mix in migratory corridors. Furthermore, we find a significant relationship between δ 13 C stable isotope profiles of 66 Australian southern right whales, a proxy for feeding ground location and both mtDNA haplotypes and kinship inferred from microsatellite-based estimators of relatedness. This indicates migratory culture may influence genetic structure on feeding grounds. This fidelity to migratory destinations is likely to influence population recovery, as long-term estimates of historical abundance derived from estimates of genetic ersity indicate the South Pacific calving grounds remain at % of pre-whaling abundance.
A Robust and Economical Underwater Stereo Video System to Observe Antarctic Krill (Euphausia superba)
Publisher: Scientific Research Publishing, Inc.
Date: 2013
Animal-borne telemetry
Publisher: Frontiers Media SA
Date: 26-06-2019
A Novel Framework to Protect Animal Data in a World of Ecosurveillance
Publisher: Oxford University Press (OUP)
Date: 29-04-2020
Abstract: Surveillance of animal movements using electronic tags (i.e., biotelemetry) has emerged as an essential tool for both basic and applied ecological research and monitoring. Advances in animal tracking are occurring simultaneously with changes to technology, in an evolving global scientific culture that increasingly promotes data sharing and transparency. However, there is a risk that misuse of biotelemetry data could increase the vulnerability of animals to human disturbance or exploitation. For the most part, telemetry data security is not a danger to animals or their ecosystems, but for some high-risk cases, as with species’ with high economic value or at-risk populations, available knowledge of their movements may promote active disturbance or worse, potential poaching. We suggest that when designing animal tracking studies it is incumbent on scientists to consider the vulnerability of their study animals to risks arising from the implementation of the proposed program, and to take preventative measures.
Marine mammal conservation: over the horizon
Publisher: Inter-Research Science Center
Date: 25-03-2021
DOI: 10.3354/ESR01115
Abstract: Marine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species. Yet, historical population declines caused by exploitation, and additional current threats, such as climate change, fisheries bycatch, pollution and maritime development, continue to impact many marine mammal species, and at least 25% are classified as threatened (Critically Endangered, Endangered or Vulnerable) on the IUCN Red List. Conversely, some species have experienced population increases/recoveries in recent decades, reflecting management interventions, and are heralded as conservation successes. To continue these successes and reverse the downward trajectories of at-risk species, it is necessary to evaluate the threats faced by marine mammals and the conservation mechanisms available to address them. Additionally, there is a need to identify evidence-based priorities of both research and conservation needs across a range of settings and taxa. To that effect we: (1) outline the key threats to marine mammals and their impacts, identify the associated knowledge gaps and recommend actions needed (2) discuss the merits and downfalls of established and emerging conservation mechanisms (3) outline the application of research and monitoring techniques and (4) highlight particular taxa opulations that are in urgent need of focus.
First evidence of bubble‐net feeding and the formation of ‘super‐groups’ by the east Australian population of humpback whales during their southward migration
Publisher: Wiley
Date: 31-05-2021
DOI: 10.1002/AQC.3621
Abstract: The recovery of overexploited populations is likely to reveal behaviours that may have been present prior to harvest but are only now reappearing as the population size increases. The east Australian humpback whale ( Megaptera novaeangliae ) population (group V, stock E1) has recovered well from past exploitation and is now estimated to be close to the pre‐whaling population size. Humpback whales were thought to follow a ‘feast and famine’ model historically, feeding intensively in high‐latitude feeding grounds and then fasting while migrating and in calving grounds however, there is growing evidence that animals may feed outside of known foraging grounds. This short article reports on the first photographically documented evidence of bubble‐net feeding by humpback whales in Australian coastal waters ( n = 10 groups observed) and provides the first evidence of a second site in the southern hemisphere for the formation of ‘super‐groups’ ( n = 6 super‐groups at discrete locations). The formation of super‐groups may be linked to changes in the type or density of prey available, either along the migratory route or in the feeding grounds of the previous summer. It is also possible that the increased population size following recovery make large group sizes while feeding more common. These findings strongly support evidence that feeding behaviour is not restricted to high‐latitude foraging grounds in the Southern Ocean, and that prey consumption prior to leaving the coastal waters of Australia may be a significant component of the migratory ecology of this population. Understanding how environmental variation influences the extent to which humpback whales depend on foraging opportunities along their migratory route, and where feeding occurs, will help to predict how future changes in the ocean will influence whale populations. This will also allow for more effective management measures to reduce the impact of threats during this important period of energy consumption.
The role of visual cues in mother–pup reunions in a colonially breeding mammal
Publisher: The Royal Society
Date: 11-2017
Abstract: Parental care is an important factor influencing offspring survival and adult reproductive success in many vertebrates. Parent–offspring recognition ensures care is only directed to filial young, avoiding the costs of misallocated resource transfer. It is essential in colonial mammal species, such as otariids (fur seals and sea lions), in which repeated mother–offspring separations increase the risk of misdirecting maternal effort. Identification of otariid pups by mothers is known to be multi-modal, yet the role of visual cues in this process remains uncertain. We used three-dimensional visual models to investigate the importance of visual cues in maternal recognition of pups in Australian sea lions ( Neophoca cinerea ). We showed that the colour pattern of pup pelage in the absence of any other sensory cues served to attract the attention of females and prompt investigation. Furthermore, females were capable of accurately distinguishing between models imitating the age-class of their own pup and those resembling older or younger age-classes. Our results suggest that visual cues facilitate age-class discrimination of pups by females and so are likely to play an important role in mother–pup reunions and recognition in otariid species.
A standardisation framework for bio‐logging data to advance ecological research and conservation
Publisher: Wiley
Date: 04-2021
Abstract: Bio‐logging data obtained by tagging animals are key to addressing global conservation challenges. However, the many thousands of existing bio‐logging datasets are not easily discoverable, universally comparable, nor readily accessible through existing repositories and across platforms, slowing down ecological research and effective management. A set of universal standards is needed to ensure discoverability, interoperability and effective translation of bio‐logging data into research and management recommendations. We propose a standardisation framework adhering to existing data principles (FAIR: Findable, Accessible, Interoperable and Reusable and TRUST: Transparency, Responsibility, User focus, Sustainability and Technology) and involving the use of simple templates to create a data flow from manufacturers and researchers to compliant repositories, where automated procedures should be in place to prepare data availability into four standardised levels: (a) decoded raw data, (b) curated data, (c) interpolated data and (d) gridded data. Our framework allows for integration of simple tabular arrays (e.g. csv files) and creation of sharable and interoperable network Common Data Form (netCDF) files containing all the needed information for accuracy‐of‐use, rightful attribution (ensuring data providers keep ownership through the entire process) and data preservation security. We show the standardisation benefits for all stakeholders involved, and illustrate the application of our framework by focusing on marine animals and by providing ex les of the workflow across all data levels, including filled templates and code to process data between levels, as well as templates to prepare netCDF files ready for sharing. Adoption of our framework will facilitate collection of Essential Ocean Variables (EOVs) in support of the Global Ocean Observing System (GOOS) and inter‐governmental assessments (e.g. the World Ocean Assessment), and will provide a starting point for broader efforts to establish interoperable bio‐logging data formats across all fields in animal ecology.
The winter migration of Adelie penguins breeding in the Ross Sea sector of Antarctica
Publisher: Springer Science and Business Media LLC
Date: 08-2001
Individual variation in predation on fur seals by southern sea lions (Otaria byronia) in Peru
Publisher: Canadian Science Publishing
Date: 09-1993
DOI: 10.1139/Z93-273
Abstract: Southern sea lions (Otaria byronia) were observed to prey on juvenile and adult female South American fur seals (Arctocephalus australis) at Punta San Juan, Peru (15°22′S, 75°12′W) between October 1987 and December 1988. Over the course of the study there were 165 attacks on fur seals with 33 seals killed. While both adult male and subadult male sea lions captured and killed fur seals, adult female and juvenile sea lions never acted aggressively towards fur seals. Adult males attacked fur seals on 82.4% of the occasions when they were present at the rookery, subadults on 52% of occasions. Distinctive pelage characteristics allowed some of the male sea lions to be in idually identified, and differences in hunting success were observed between adults and subadults, and between five identifiable adults who hunted on at least five occasions. Motivation for attacks differed for subadults and adults, with subadult males using captured fur seals as female sea lion substitutes, guarding them from others and copulating with them, whilst adult sea lions hunted fur seals as food. However, only a small proportion of adult sea lions hunted fur seals, and with differing rates of success.
Reply to: Caution over the use of ecological big data for conservation
Publisher: Springer Science and Business Media LLC
Date: 07-07-2021
Giant Australian cuttlefish use mutual assessment to resolve male-male contests
Publisher: Elsevier BV
Date: 09-2015
Under the sea ice: Exploring the relationship between sea ice and the foraging behaviour of southern elephant seals in East Antarctica
Publisher: Elsevier BV
Date: 08-2017
Seasonal variation in the diet of New Zealand fur seals (Arctocephalus forsteri) at Otago Peninsula, New Zealand
Publisher: CSIRO Publishing
Date: 1999
DOI: 10.1071/WR98024
Abstract: We examined the diet of New Zealand fur seals (Arctocephalus forsteri) at a rookery on Otago Peninsula, New Zealand, by analysing diagnostic remains from 500 faecal s les and 84 regurgitates collected between July 1993 and September 1994. In total, 27 taxa (species or genera) were identified. Small fish were numerically dominant in faecal s les, with five fish species (three species of lanternfish (Myctophidae), ahuru (Auchenoceros punctatus) and juvenile red cod (Pseudophycis bachus)) accounting for over 90% of prey items. Regurgitates occurred only seasonally and contained predominantly cephalopod remains (99% of prey items). Numerical analyses may prove misleading as an indicator of the composition of seal diet because the contribution of large fish that dominate estimates of prey biomass are underrepresented. Estimates of prey biomass were made by combining estimates from both faecal and regurgitate s les. Possible biases created by using this method are considered. A seasonal variation in prey composition was apparent, with arrow squid (Nototodarus sloanii) dominant in summer and autumn, replaced by a combination of barracouta (Thrysites atun), mackerel (Trachurus sp.) and New Zealand octopus (Octopus maorum) in winter and spring.
Chemical fingerprints suggest direct familiarisation rather than phenotype matching during olfactory recognition in Australian sea lions (Neophoca cinerea)
Publisher: Elsevier BV
Date: 08-2019
Deep Learning Resolves Representative Movement Patterns in a Marine Predator Species
Publisher: MDPI AG
Date: 23-07-2019
DOI: 10.3390/APP9142935
Abstract: The analysis of animal movement from telemetry data provides insights into how and why animals move. While traditional approaches to such analysis mostly focus on predicting animal states during movement, we describe an approach that allows us to identify representative movement patterns of different animal groups. To do this, we propose a carefully designed recurrent neural network and combine it with telemetry data for automatic feature extraction and identification of non-predefined representative patterns. In the experiment, we consider a particular marine predator species, the southern elephant seal, as an ex le. With our approach, we identify that the male seals in our data set share similar movement patterns when they are close to land. We identify this pattern recurring in a number of distant locations, consistent with alternative approaches from previous research.
A Southern Indian Ocean database of hydrographic profiles obtained with instrumented elephant seals
Publisher: Springer Science and Business Media LLC
Date: 02-09-2014
Abstract: The instrumentation of southern elephant seals with satellite-linked CTD tags has offered unique temporal and spatial coverage of the Southern Indian Ocean since 2004. This includes extensive data from the Antarctic continental slope and shelf regions during the winter months, which is outside the conventional areas of Argo autonomous floats and ship-based studies. This landmark dataset of around 75,000 temperature and salinity profiles from 20–140 °E, concentrated on the sector between the Kerguelen Islands and Prydz Bay, continues to grow through the coordinated efforts of French and Australian marine research teams. The seal data are quality controlled and calibrated using delayed-mode techniques involving comparisons with other existing profiles as well as cross-comparisons similar to established protocols within the Argo community, with a resulting accuracy of ±0.03 °C in temperature and ±0.05 in salinity or better. The data offer invaluable new insights into the water masses, oceanographic processes and provides a vital tool for oceanographers seeking to advance our understanding of this key component of the global ocean climate.
Effects of capture stress on free-ranging, reproductively active male Weddell seals
Publisher: Springer Science and Business Media LLC
Date: 05-01-2010
DOI: 10.1007/S00359-009-0501-0
Abstract: Physiological stress responses to capture may be an indicator of welfare challenges induced by animal handling. Simultaneously, blood chemistry changes induced by stress responses may confound experimental design by interacting with the biological parameters being measured. Cortisol elevation is a common indicator of stress responses in mammals and reproductive condition can profoundly influence endocrine response. We measured changes in blood cortisol and testosterone induced by handling reproductively active male Weddell seals (Leptonychotes weddellii) early and late in the breeding season. Weddell seals have the highest resting cortisol levels of all mammals yet showed a clear, prolonged elevation in cortisol in response to capture. Responses were similar when first caught and when caught a second time, later in the breeding season. Baseline testosterone levels declined over the breeding season but were not altered by capture. Administering a light dose of diazepam significantly ameliorated the cortisol response of handled animals without affecting testosterone levels. This may be an effective way of reducing acute capture stress responses. Male breeding success in years males were handled was no different to the years they were not, despite the acute capture response, suggesting no long-term impact of handling on male reproductive output.
Colony Location and Captivity Influence the Gut Microbial Community Composition of the Australian Sea Lion (Neophoca cinerea)
Publisher: American Society for Microbiology
Date: 15-06-2016
DOI: 10.1128/AEM.00192-16
Abstract: Gut microbiota play an important role in maintenance of mammalian metabolism and immune system regulation, and disturbances to this community can have adverse impacts on animal health. To better understand the composition of gut microbiota in marine mammals, fecal bacterial communities of the Australian sea lion ( Neophoca cinerea ), an endangered pinniped with localized distribution, were examined. A comparison of s les from in iduals across 11 wild colonies in South and Western Australia and three Australian captive populations showed five dominant bacterial phyla: Firmicutes , Proteobacteria , Bacteroidetes , Actinobacteria , and Fusobacteria . The phylum Firmicutes was dominant in both wild (76.4% ± 4.73%) and captive animals (61.4% ± 10.8%), while Proteobacteria contributed more to captive (29.3% ± 11.5%) than to wild (10.6% ± 3.43%) fecal communities. Qualitative differences were observed between fecal communities from wild and captive animals based on principal-coordinate analysis. SIMPER (similarity percentage procedure) analyses indicated that operational taxonomic units (OTU) from the bacterial families Clostridiaceae and Ruminococcaceae were more abundant in wild than in captive animals and contributed most to the average dissimilarity between groups (SIMPER contributions of 19.1% and 10.9%, respectively). Differences in the biological environment, the foraging site fidelity, and anthropogenic impacts may provide various opportunities for unique microbial establishment in Australian sea lions. As anthropogenic disturbances to marine mammals are likely to increase, understanding the potential for such disturbances to impact microbial community compositions and subsequently affect animal health will be beneficial for management of these vulnerable species. IMPORTANCE The Australian sea lion is an endangered species for which there is currently little information regarding disease and microbial ecology. In this work, we present an in-depth study of the fecal microbiota of a large number of Australian sea lions from geographically erse wild and captive populations. Colony location and captivity were found to influence the gut microbial community compositions of these animals. Our findings significantly extend the baseline knowledge of marine mammal gut microbiome composition and variability.
Video playback demonstrates episodic personality in the gloomy octopus
Publisher: The Company of Biologists
Date: 04-2010
DOI: 10.1242/JEB.040675
Abstract: Coleoid cephalopods, including octopuses, cuttlefish and squid, rely mainly on visual signals when interacting with conspecifics, predators and prey. Presenting visual stimuli, such as models, photographs, mirrors and live conspecifics, can thus provide insight into cephalopod behaviour. These methods, however, have limitations – mirrors and live animals lack experimental control, whereas models and photographs sacrifice motion-based information. Video playback addresses these issues by presenting controlled, moving and realistic stimuli but, to date, video playback has not been used successfully with any cephalopod. Here, we developed a video playback technique for the gloomy octopus (Octopus tetricus) that incorporated recent advances in video technology. We then used this technique to test for personality, which we defined as behavioural differences between in iduals that are consistent over time and across ecologically important contexts. We captured wild octopuses and tested them on 3 separate days over a 10 day period. On each test day, subjects were presented with videos of a food item, a novel object and a conspecific. These represented a foraging, novel and threatening context, respectively. A fourth video without a moving stimulus controlled for the playback monitor itself and potential artifacts associated with video playback. Experimental stimuli evoked unambiguous and biologically appropriate responses from the subjects. Furthermore, in iduals' responses to the three experimental contexts were highly correlated within a given test day. However, within a given context, in iduals behaved inconsistently across the 3 test days. The reordering of ranks suggests that rather than fulfilling the criteria for personality, gloomy octopus show temporal discontinuities, and hence display episodic personality.
Assessing the potential for resource competition between the Kerguelen Plateau fisheries and southern elephant seals
Publisher: Frontiers Media SA
Date: 18-11-2022
DOI: 10.3389/FMARS.2022.1006120
Abstract: Indirect ecological interactions such as competition for resources between fisheries and marine predators have often been proposed but can be difficult to demonstrate empirically. The Kerguelen Plateau in the Southern Indian Ocean supports fisheries for both Patagonian toothfish and mackerel icefish and is also an important foraging ground for several avian and mammalian predators, including the southern elephant seal. We quantified the spatio-temporal use of the plateau by southern elephant seals and found that males and females spent 30% of their time on the plateau within the commonly used fishing grounds, indicating the possibility of competition for resources there. We then contrasted the seals’ use of two habitat types, the benthos (where interactions with the long-line fisheries are most likely) and the epi-pelagic zone. The likelihood of feeding on the benthos declined as ocean depth increased and was also less likely at night. Males were also more likely to feed on the benthos than females. The sub-adult male seals consumed an estimated 6,814 – 14,848 tons of high energy content prey (including toothfish) and females 7,085 – 18,037 tons from the plateau during the post-molt winter months. For males this represented 79.6 - 173.4% of the mean annual catch by the Kerguelen fishery compared to 82.8 - 210.7% for adult females. When considering the seals consumption of fish from the benthos within the fishing grounds these estimates decreased to 3.6 - 15.1% of the fishery’s total annual catch for females and 7.8 - 19.1% for males. While this further indicates the possibility of indirect ecological interactions (with the fishery taking more fish than the seals), the lack of detailed diet information for the seals precludes us from establishing the degree or nature of the possible interactions because the importance of toothfish and icefish in the diet of the seals is unknown. However, the unique life history and highly polygynous nature of this species, and the lack of evidence of a measurable effect on either the seal’s population growth rates or the catch per unit of the fishery, suggest that any indirect ecological interactions are not of sufficient magnitude to affect either the seal population or the fishery.
Refining instrument attachment on phocid seals
Publisher: Wiley
Date: 04-09-2011
Management implications for the changing interactions between people and whales in Ha'apai, Tonga
Publisher: Elsevier BV
Date: 03-2012
Best practice framework and principles for monitoring the effect of coastal development on marine mammals
Publisher: Frontiers Media SA
Date: 07-03-2017
Population structure and individual movement of southern right whales around New Zealand and Australia
Publisher: Inter-Research Science Center
Date: 27-06-2011
DOI: 10.3354/MEPS09145
Ontogenetic changes in the tooth morphology of bull sharks (Carcharhinus leucas).
Publisher: Wiley
Date: 03-08-2022
DOI: 10.1111/JFB.15170
Abstract: Teeth are an integral component of feeding ecology, with a clear link between tooth morphology and diet, as without suitable dentition prey cannot be captured nor broken down for consumption. Bull sharks, Carcharhinus leucas, undergo an ontogenetic niche shift from freshwater to marine habitats, which raises the question: does tooth morphology change with ontogeny? Tooth shape, surface area and thickness were measured using both morphometrics and elliptic Fourier analysis to determine if morphology varied with position in the jaw and if there was an ontogenetic change concordant with this niche shift. Significant ontogenetic differences in tooth morphology as a function of position in the jaw and shark total length were found, with upper and lower jaws of bull sharks presenting two different tooth morphologies. Tooth shape and thickness fell into two groupings, anterior and posterior, in both the upper and lower jaws. Tooth surface area, however, indicated three groupings, mesial, intermediate and distal, in both the upper and lower jaws. While tooth morphology changed significantly with size, showing an inflection at sharks of 135 cm total length, each morphological aspect retained the same tooth groupings throughout. These ontogenetic differences in tooth morphologies reflect tooth strength, prey handling and heterodonty.
Differential Mobilization of Blubber Fatty Acids in Lactating Weddell Seals: Evidence for Selective Use
Publisher: University of Chicago Press
Date: 09-2008
DOI: 10.1086/590397
Abstract: A major source of energy during lactation in mammals is provided through the mobilization of blubber fatty acids (FAs). We investigated the extent to which FAs were mobilized to support both maternal metabolic requirements and milk production in the Weddell seal and how this was reflected in the FA composition of the pup's blubber at the end of lactation (EL). FA composition of postpartum female blubber was similar in the 2 yr of study (2002 and 2003) but differed markedly by EL. Pup blubber FAs (at EL) were also different between years and did not match that of the mother's milk or blubber. Milk FA composition changed during lactation, which may have been a reflection of an increase in pup energy demands at different stages of development. In addition, there was evidence of feeding by some females during lactation, with higher levels of some FAs in the milk than in the blubber. Our results indicate that differential mobilization of FAs occurred in lactating Weddell seals and that this was related to total body lipid stores at postpartum. Furthermore, growing pups did not store FAs unmodified, providing evidence that selective use does occur and also that using FA composition to elucidate dietary sources may be problematic in growing in iduals.
Animal Borne Ocean Sensors – AniBOS – an essential component of the Global Ocean Observing System
Publisher: Frontiers Media SA
Date: 05-11-2021
DOI: 10.3389/FMARS.2021.751840
Abstract: Marine animals equipped with biological and physical electronic sensors have produced long-term data streams on key marine environmental variables, hydrography, animal behavior and ecology. These data are an essential component of the Global Ocean Observing System (GOOS). The Animal Borne Ocean Sensors (AniBOS) network aims to coordinate the long-term collection and delivery of marine data streams, providing a complementary capability to other GOOS networks that monitor Essential Ocean Variables (EOVs), essential climate variables (ECVs) and essential bio ersity variables (EBVs). AniBOS augments observations of temperature and salinity within the upper ocean, in areas that are under-s led, providing information that is urgently needed for an improved understanding of climate and ocean variability and for forecasting. Additionally, measurements of chlorophyll fluorescence and dissolved oxygen concentrations are emerging. The observations AniBOS provides are used widely across the research, modeling and operational oceanographic communities. High latitude, shallow coastal shelves and tropical seas have historically been s led poorly with traditional observing platforms for many reasons including sea ice presence, limited satellite coverage and logistical costs. Animal-borne sensors are helping to fill that gap by collecting and transmitting in near real time an average of 500 temperature-salinity-depth profiles per animal annually and, when instruments are recovered (∼30% of instruments deployed annually, n = 103 ± 34), up to 1,000 profiles per month in these regions. Increased observations from under-s led regions greatly improve the accuracy and confidence in estimates of ocean state and improve studies of climate variability by delivering data that refine climate prediction estimates at regional and global scales. The GOOS Observations Coordination Group (OCG) reviews, advises on and coordinates activities across the global ocean observing networks to strengthen the effective implementation of the system. AniBOS was formally recognized in 2020 as a GOOS network. This improves our ability to observe the ocean’s structure and animals that live in them more comprehensively, concomitantly improving our understanding of global ocean and climate processes for societal benefit consistent with the UN Sustainability Goals 13 and 14: Climate and Life below Water. Working within the GOOS OCG framework ensures that AniBOS is an essential component of an integrated Global Ocean Observing System.
Editorial: Small cetacean conservation: Current challenges and opportunities
Publisher: Frontiers Media SA
Date: 08-2022
Environmental correlates of temporal variation in the prey species of Australian fur seals inferred from scat analysis
Publisher: The Royal Society
Date: 10-2022
DOI: 10.1098/RSOS.211723
Abstract: Marine ecosystems in southeastern Australia are responding rapidly to climate change. We monitored the diet of the Australian fur seal ( Arctocephalus pusillus doriferus ), a key marine predator, over 17 years (1998–2014) to examine temporal changes. Frequency of occurrence (FO) of prey was used as a proxy for ecosystem change. Hard part analysis identified 71 prey taxa, with eight dominant taxa in greater than 70% of s les and predominantly included benthic and small pelagic fish. FO changed over time, e.g. redbait ( Emmelichthys nitidus ) reduced after 2005 when jack mackerel ( Trachurus declivis ) increased, and pilchard ( Sardinops sajax ) increased after 2009. Using generalized additive models, correlations between FO and environmental variables were evident at both the local (e.g. wind, sea surface temperature (SST)) and regional (e.g. El Niño–Southern Oscillation Index (SOI), Southern Annular Mode (SAM)) scales, with redbait and pilchard showing the best model fits (greater than 75% deviance explained). Positive SAM was correlated to FO for both species, and wind and season were important for redbait, while SOI and SST were important for pilchard. Both large-scale and regional processes influenced prey taxa in variable ways. We predict that the erse and adaptable diet of the Australian fur seal will be advantageous in a rapidly changing ecosystem.
Factors affecting early mortality in the South American fur seal (Arctocephalus australis) in Peru: density‐related effects and predation
Publisher: Wiley
Date: 02-1992
Aquatic animal telemetry: A panoramic window into the underwater world
Publisher: American Association for the Advancement of Science (AAAS)
Date: 12-06-2015
Abstract: Researchers have long attempted to follow animals as they move through their environment. Until relatively recently, however, such efforts were limited to short distances and times in species large enough to carry large batteries and transmitters. New technologies have opened up new frontiers in animal tracking remote data collection. Hussey et al. review the unique directions such efforts have taken for marine systems, while Kays et al. review recent advances for terrestrial species. We have entered a new era of animal ecology, where animals act as both subjects and s lers of their environments. Science , this issue 10.1126/science.1255642 , 10.1126/science.aaa2478
Frequency of Multiple Paternity in Gummy Shark, Mustelus antarcticus, and Rig, Mustelus lenticulatus, and the Implications of Mate Encounter Rate, Postcopulatory Influences, and Reproductive Mode
Publisher: Oxford University Press (OUP)
Date: 15-03-2013
Abstract: Elasmobranchs (sharks and rays) show an amazing ersity of reproductive modes and behaviors. Multiple paternity (MP) has been identified in all species where more than 1 litter has been investigated yet neither direct nor indirect benefits from MP have been determined in elasmobranchs. This has led to the suggestion that MP in this group may simply be a product of convenience polyandry with variation in the frequency of MP driven by differences in mate encounter rates. Here, we use molecular markers to investigate polyandry and MP in 2 closely related and commercially important species of shark, Mustelus antarcticus and Mustelus lenticulatus. In total, 328 M. antarcticus embryos originating from 29 different mothers and 75 M. lenticulatus embryos originating from 19 different mothers were genotyped using 8 microsatellite loci. We find that MP occurs in both species. However, in both species, the majority of litters were sired by a single father. Our results do not support increased fecundity per se as a driver of MP. Further, our results do not suggest that high population densities with resulting high mate encounter rates generated by breeding aggregations necessarily lead to high frequencies of MP. Importantly, we note evidence of reproductive skew within polyandrous litters, which is a predicted outcome of postcopulatory mechanisms.
A continuous-time state-space model for rapid quality control of Argos locations from animal-borne tags
Publisher: Springer Science and Business Media LLC
Date: 03-03-2027
DOI: 10.1186/S40462-020-00217-7
Abstract: State-space models are important tools for quality control and analysis of error-prone animal movement data. The near real-time (within 24 h) capability of the Argos satellite system can aid dynamic ocean management of human activities by informing when animals enter wind farms, shipping lanes, and other intensive use zones. This capability also facilitates the use of ocean observations from animal-borne sensors in operational ocean forecasting models. Such near real-time data provision requires rapid, reliable quality control to deal with error-prone Argos locations. We formulate a continuous-time state-space model to filter the three types of Argos location data (Least-Squares, Kalman filter, and Kalman smoother), accounting for irregular timing of observations. Our model is deliberately simple to ensure speed and reliability for automated, near real-time quality control of Argos location data. We validate the model by fitting to Argos locations collected from 61 in iduals across 7 marine vertebrates and compare model-estimated locations to contemporaneous GPS locations. We then test assumptions that Argos Kalman filter/smoother error ellipses are unbiased, and that Argos Kalman smoother location accuracy cannot be improved by subsequent state-space modelling. Estimation accuracy varied among species with Root Mean Squared Errors usually km and these decreased with increasing data s ling rate and precision of Argos locations. Including a model parameter to inflate Argos error ellipse sizes in the north - south direction resulted in more accurate location estimates. Finally, in some cases the model appreciably improved the accuracy of the Argos Kalman smoother locations, which should not be possible if the smoother is using all available information. Our model provides quality-controlled locations from Argos Least-Squares or Kalman filter data with accuracy similar to or marginally better than Argos Kalman smoother data that are only available via fee-based reprocessing. Simplicity and ease of use make the model suitable both for automated quality control of near real-time Argos data and for manual use by researchers working with historical Argos data.
Australia’s continental-scale acoustic tracking database and its automated quality control process
Publisher: Springer Science and Business Media LLC
Date: 30-01-2018
Abstract: Our ability to predict species responses to environmental changes relies on accurate records of animal movement patterns. Continental-scale acoustic telemetry networks are increasingly being established worldwide, producing large volumes of information-rich geospatial data. During the last decade, the Integrated Marine Observing System’s Animal Tracking Facility (IMOS ATF) established a permanent array of acoustic receivers around Australia. Simultaneously, IMOS developed a centralised national database to foster collaborative research across the user community and quantify in idual behaviour across a broad range of taxa. Here we present the database and quality control procedures developed to collate 49.6 million valid detections from 1891 receiving stations. This dataset consists of detections for 3,777 tags deployed on 117 marine species, with distances travelled ranging from a few to thousands of kilometres. Connectivity between regions was only made possible by the joint contribution of IMOS infrastructure and researcher-funded receivers. This dataset constitutes a valuable resource facilitating meta-analysis of animal movement, distributions, and habitat use, and is important for relating species distribution shifts with environmental covariates.
Connectivity in grey reef sharks (Carcharhinus amblyrhynchos) determined using empirical and simulated genetic data
Publisher: Springer Science and Business Media LLC
Date: 28-08-2015
DOI: 10.1038/SREP13229
Abstract: Grey reef sharks ( Carcharhinus amblyrhynchos ) can be one of the numerically dominant high order predators on pristine coral reefs, yet their numbers have declined even in the highly regulated Australian Great Barrier Reef (GBR) Marine Park. Knowledge of both large scale and fine scale genetic connectivity of grey reef sharks is essential for their effective management, but no genetic data are yet available. We investigated grey reef shark genetic structure in the GBR across a 1200 km latitudinal gradient, comparing empirical data with models simulating different levels of migration. The empirical data did not reveal any genetic structuring along the entire latitudinal gradient s led, suggesting regular widespread dispersal and gene flow of the species throughout most of the GBR. Our simulated datasets indicate that even with substantial migrations (up to 25% of in iduals migrating between neighboring reefs) both large scale genetic structure and genotypic spatial autocorrelation at the reef scale were maintained. We suggest that present migration rates therefore exceed this level. These findings have important implications regarding the effectiveness of networks of spatially discontinuous Marine Protected Areas to protect reef sharks.
Chemical immobilization of adult female Weddell seals with tiletamine and zolazepam: effects of age, condition and stage of lactation
Publisher: Springer Science and Business Media LLC
Date: 09-02-2006
Abstract: Chemical immobilization of Weddell seals ( Leptonychotes weddellii ) has previously been, for the most part, problematic and this has been mainly attributed to the type of immobilizing agent used. In addition to in idual sensitivity, physiological status may play an important role. We investigated the use of the intravenous administration of a 1:1 mixture of tiletamine and zolazepam (Telazol ® ) to immobilize adult females at different points during a physiologically demanding 5–6 week lactation period. We also compared performance between IV and IM injection of the same mixture. The tiletamine:zolazepam mixture administered intravenously was an effective method for immobilization with no fatalities or pronounced apnoeas in 106 procedures however, there was a 25 % (one animal in four) mortality rate with intramuscular administration. Induction time was slightly longer for females at the end of lactation (54.9 ± 2.3 seconds) than at post-parturition (48.2 ± 2.9 seconds). In addition, the number of previous captures had a positive effect on induction time. There was no evidence for effects due to age, condition (total body lipid), stage of lactation or number of captures on recovery time. We suggest that intravenous administration of tiletamine and zolazepam is an effective and safe immobilizing agent for female Weddell seals. Although in idual traits could not explain variation in recovery time, we suggest careful monitoring of recovery times during longitudinal studies ( 2 captures). We show that physiological pressures do not substantially affect response to chemical immobilization with this mixture however, consideration must be taken for differences that may exist for immobilization of adult males and juveniles. Nevertheless, we recommend a mass-specific dose of 0.50 – 0.65 mg/kg for future procedures with adult female Weddell seals and a starting dose of 0.50 mg/kg for other age classes and other phocid seals.
Foraging ecology of a generalist predator, the female New Zealand fur seal
Publisher: Inter-Research Science Center
Date: 2002
DOI: 10.3354/MEPS227011
Environmental drivers of foraging behaviour during long-distance foraging trips of male Antarctic fur seals
Publisher: Elsevier BV
Date: 2022
Variability in sea ice cover and climate elicit sex specific responses in an Antarctic predator
Publisher: Springer Science and Business Media LLC
Date: 24-02-2017
DOI: 10.1038/SREP43236
Abstract: Contrasting regional changes in Southern Ocean sea ice have occurred over the last 30 years with distinct regional effects on ecosystem structure and function. Quantifying how Antarctic predators respond to such changes provides the context for predicting how climate variability/change will affect these assemblages into the future. Over an 11-year time-series, we examine how inter-annual variability in sea ice concentration and advance affect the foraging behaviour of a top Antarctic predator, the southern elephant seal. Females foraged longer in pack ice in years with greatest sea ice concentration and earliest sea ice advance, while males foraged longer in polynyas in years of lowest sea ice concentration. There was a positive relationship between near-surface meridional wind anomalies and female foraging effort, but not for males. This study reveals the complexities of foraging responses to climate forcing by a poleward migratory predator through varying sea ice property and dynamic anomalies.
An outpatient survey of antidepressant prescription habits
Publisher: SAGE Publications
Date: 12-1986
DOI: 10.3109/00048678609158901
Abstract: A review of case notes of patients attending a general hospital psychiatric outpatient clinic revealed that 75% of patients with depressive disorders and 38% of patients with neurotic disorders were prescribed antidepressants. Antidepressants were often prescribed for long periods in low doses and in combination with benzodiazepines. There was less polypharmacy, however, with more sedating antidepressants. The results indicate that clinical prescription habits for antidepressants may still be at some variance with recommendations from the literature.
Prior exposure to capture heightens the corticosterone and behavioural responses of little penguins (Eudyptula minor) to acute stress
Publisher: Oxford University Press (OUP)
Date: 2016
Tracking sea turtle hatchlings — A pilot study using acoustic telemetry
Publisher: Elsevier BV
Date: 02-2013
Reproductive synchrony of three sympatric species of wobbegong shark (genus Orectolobus) in New South Wales, Australia: reproductive parameter estimates necessary for population modelling
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/MF06187
Abstract: Reproductive parameters of three closely-related sympatric species of wobbegong (Orectolobus ornatus, O. maculatus and O. halei) off New South Wales (NSW) were investigated to contribute to a biological basis for the management of a commercial fishery targeting wobbegongs. Estimates of the onset of maturity based on ovary condition were 729 mm, 1117 mm, and 1591 mm total length (TL) for O. ornatus, O. maculatus and O. halei respectively. The length at which 50% of the male population is mature based on clasper calcification was 803 mm, 1282 mm and 1784 mm TL for O. ornatus, O. maculatus and O. halei, respectively, and was similar to female onset of maturity based on uterus condition and to TL-at-maternity. These species of wobbegong had synchronous, triennial reproductive cycles. Follicles took 2 years to enlarge before ovulation. During the first year, follicles remained small, and then grew rapidly during the second year before ovulation during November. Gestation lasted ~10–11 months and parturition occurred during September–October. Mean litter sizes were nine (s.e. 0.5) and 21 (s.e. 1.5) for O. ornatus and O. maculatus, respectively, and increased with female total length in O. ornatus. Pregnant O. ornatus and O. maculatus were frequently caught in northern NSW and no pregnant wobbegongs, or females with large, yolky follicles were captured south of Sydney. Differences in the reproductive conditions of wobbegongs caught in northern and central NSW suggested geographically dependent reproductive behaviour. Knowledge of the reproductive parameters provided in this paper is necessary for adequate fisheries management and species conservation assessments.
Steady as He Goes: At-Sea Movement of Adult Male Australian Sea Lions in a Dynamic Marine Environment
Publisher: Public Library of Science (PLoS)
Date: 25-09-2013
Predicting krill swarm characteristics important for marine predators foraging off East Antarctica
Publisher: Wiley
Date: 27-09-2018
DOI: 10.1111/ECOG.03080
Adaptations of the red fox (Vulpes vulpes) to urban environments in Sydney, Australia
Publisher: Oxford University Press (OUP)
Date: 25
DOI: 10.1093/JUE/JUAA009
Abstract: With urban encroachment on wild landscapes accelerating globally, there is an urgent need to understand how wildlife is adapting to anthropogenic change. We compared the behaviour of the invasive red fox (Vulpes vulpes) at eight urban and eight peri-urban areas of Sydney, Australia. We observed fox behaviour around a lure and compared fox activity patterns to those of potential prey and to two domestic predators (dogs—Canis lupus familiaris and cats—Felis catus). We assessed the influence of site type, vegetation cover, and distance from habitation on fox behaviour, and compared the temporal activity patterns of urban and peri-urban red foxes. Urban red foxes were marginally more nocturnal than those in peri-urban areas (88% activity overlap). There was greater overlap of red fox activity patterns with introduced mammalian prey in urban areas compared with peri-urban areas (90% urban vs 84% peri-urban). Red fox temporal activity overlapped 78% with cats, but only 20% with dogs, across both site types. The high degree of overlap with cats and introduced mammalian prey is most likely explained by the nocturnal behaviour of these species, while pet dogs are generally kept in yards or indoors at night. The behavioural differences we documented by urban red foxes suggest they may adapt to human modifications and presence, by being more nocturnal and/or more confident in urban areas.
Size isn't everything: movements, home range, and habitat preferences of eastern blue gropers (Achoerodus viridis) demonstrate the efficacy of a small marine reserve
Publisher: Wiley
Date: 06-02-2014
DOI: 10.1002/AQC.2431
Identifying key habitats for the conservation of Chilean dolphins in the fjords of southern Chile
Publisher: Wiley
Date: 20-03-2015
DOI: 10.1002/AQC.2553
Fine-scale movement patterns of the sympatric Chilean and Peale’s dolphins in the northernPatagonian fjords, Chile
Publisher: Inter-Research Science Center
Date: 31-08-2011
DOI: 10.3354/MEPS09251
Taking animal tracking to new depths
Publisher: Wiley
Date: 02-2015
DOI: 10.1890/14-0469.1
Abstract: In animal ecology, a question of key interest for aquatic species is how changes in movement behavior are related in the horizontal and vertical dimensions when in iduals forage. Alternative theoretical models and inconsistent empirical findings mean that this question remains unresolved. Here we tested expectations by incorporating the vertical dimension ( e information) when predicting switching between movement states ("resident" or "directed") within a state-space model. We integrated telemetry-based tracking and ing data available for four seal species (southern elephant, Weddell, antarctic fur, and crabeater) in East Antarctica. Where possible, we included e variables derived from the relationships between (1) e duration and depth (as a measure of effort), and (2) e duration and the post e surface interval (as a physiological measure of cost). Our results varied within and across species, but there was a general tendency for the probability of switching into "resident" state to be positively associated with shorter e durations (for a given depth) and longer post e surface intervals (for a given e duration). Our results add to a growing body of literature suggesting that simplistic interpretations of optimal foraging theory based only on horizontal movements do not directly translate into the vertical dimension in dynamic marine environments. Analyses that incorporate at least two dimensions can test more sophisticated models of foraging behavior.
Lipid extraction has tissue-dependent effects on isotopic values (δ
Publisher: Wiley
Date: 27-07-2022
DOI: 10.1002/RCM.9346
Abstract: The use of sulfur isotopes to study trophic ecology in marine ecosystems has increased in the past decade. Unlike other commonly used isotopes (e.g., carbon), sulfur can better discriminate benthic and pelagic productivity. However, how lipid extraction affects sulfur isotopic values has not been assessed, despite its frequent use to remove lipid effects on δ We used white muscle and liver s les from two species of sharks and skin s les from two species of pinnipeds (sea lion and fur seal) to assess the effects of lipid extraction on stable isotope values for δ Lipid extraction significantly decreased δ Lipid extraction did not have a strong impact on δ
Age-specific cost of first reproduction in female southern elephant seals
Publisher: The Royal Society
Date: 05-2014
Abstract: When to commence breeding is a crucial life-history decision that may be the most important determinant of an in idual's lifetime reproductive output and can have major consequences on population dynamics. The age at which in iduals first reproduce is an important factor influencing the intensity of potential costs (e.g. reduced survival) involved in the first breeding event. However, quantifying age-related variation in the cost of first reproduction in wild animals remains challenging because of the difficulty in reliably recording the first breeding event. Here, using a multi-event capture–recapture model that accounts for both imperfect detection and uncertainty in the breeding status on an 18-year dataset involving 6637 in iduals, we estimated age and state-specific survival of female elephant seals ( Mirounga leonina ) in the declining Macquarie Island population. We detected a clear cost of first reproduction on survival. This cost was higher for both younger first-time breeders and older first-time breeders compared with females recruiting at age four, the overall mean age at first reproduction. Neither earlier primiparity nor delaying primiparity appear to confer any evolutionary advantage, rather the optimal strategy seems to be to start breeding at a single age, 4 years.
Female receptivity, mating history, and familiarity influence the mating behavior of cuttlefish
Publisher: Springer Science and Business Media LLC
Date: 09-11-2014
Key Questions in Marine Megafauna Movement Ecology
Publisher: Elsevier BV
Date: 06-2016
DOI: 10.1016/J.TREE.2016.02.015
Abstract: It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology.
Long-term stability in the circumpolar foraging range of a Southern Ocean predator between the eras of whaling and rapid climate change
Publisher: Proceedings of the National Academy of Sciences
Date: 27-02-2023
Abstract: Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis ), that forages on copepods and krill from ~30°S to the Antarctic ice edge ( °S). We analyzed carbon and nitrogen isotope values of 1,002 skin s les from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude ( °S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change.
Opportunistic sightings of blue whales off Sydney, Australia
Publisher: Royal Zoological Society of New South Wales
Date: 12-07-2021
DOI: 10.7882/AZ.2021.020
Abstract: Two subspecies of blue whale occur in Australian waters, (1) the pygmy blue whale (Balaenoptera musculus brevicauda) and (2) the Antarctic blue whale (Balaenoptera musculus intermedia). Understanding blue whale presence in Australian waters is critical to ensuring Australia’s protection of these marine mammals as both subspecies were heavily exploited during historical whaling. This short note documents pygmy blue whale sightings in New South Wales waters over the last 18 years. Observations were opportunistically made via citizen science and verified by scientists. Sightings in this note contribute to our limited knowledge of pygmy blue whale distribution along the east coast of Australia and may help understand the migratory movements of New Zealand pygmy blue whales off Australia and in the Tasman Sea. Overall, information presented in this note contributes to Australia’s national and international conservation efforts to protecting blue whales as a migratory and threatened species.
MOLECULAR DETECTION OF ANTIBIOTIC-RESISTANCE DETERMINANTS IN ESCHERICHIA COLI ISOLATED FROM THE ENDANGERED AUSTRALIAN SEA LION (NEOPHOCA CINEREA)
Publisher: Wildlife Disease Association
Date: 07-2015
DOI: 10.7589/2014-08-200
Abstract: Greater interaction between humans and wildlife populations poses significant risks of anthropogenic impact to natural ecosystems, especially in the marine environment. Understanding the spread of microorganisms at the marine interface is therefore important if we are to mitigate adverse effects on marine wildlife. We investigated the establishment of Escherichia coli in the endangered Australian sea lion (Neophoca cinerea) by comparing fecal isolation from wild and captive sea lion populations. Fecal s les were collected from wild colonies March 2009-September 2010 and from captive in iduals March 2011-May 2013. Using molecular screening, we assigned a phylotype to E. coli isolates and determined the presence of integrons, mobile genetic elements that capture gene cassettes conferring resistance to antimicrobial agents common in fecal coliforms. Group B2 was the most abundant phylotype in all E. coli isolates (n = 37), with groups A, B1, and D also identified. Integrons were not observed in E. coli (n = 21) isolated from wild sea lions, but were identified in E. coli from captive animals (n = 16), from which class I integrases were detected in eight isolates. Sequencing of gene cassette arrays identified genes conferring resistance to streptomycin-spectinomycin (aadA1) and trimethoprim (dfrA17, dfrB4). Class II integrases were not detected in the E. coli isolates. The frequent detection in captive sea lions of E. coli with resistance genes commonly identified in human clinical cases suggests that conditions experienced in captivity may contribute to establishment. Identification of antibiotic resistance in the microbiota of Australian sea lions provides crucial information for disease management. Our data will inform conservation management strategies and provide a mechanism to monitor microorganism dissemination to sensitive pinniped populations.
Envisioning the Future of Aquatic Animal Tracking: Technology, Science, and Application
Publisher: Oxford University Press (OUP)
Date: 13-09-2017
Known unknowns in an imperfect world: incorporating uncertainty in recruitment estimates using multi‐event capture–recapture models
Publisher: Wiley
Date: 25-10-2013
DOI: 10.1002/ECE3.846
Continental-scale animal tracking reveals functional movement classes across marine taxa
Publisher: Springer Science and Business Media LLC
Date: 27-02-2018
DOI: 10.1038/S41598-018-21988-5
Abstract: Acoustic telemetry is a principle tool for observing aquatic animals, but coverage over large spatial scales remains a challenge. To resolve this, Australia has implemented the Integrated Marine Observing System’s Animal Tracking Facility which comprises a continental-scale hydrophone array and coordinated data repository. This national acoustic network connects localized projects, enabling simultaneous monitoring of multiple species over scales ranging from 100 s of meters to 1000 s of kilometers. There is a need to evaluate the utility of this national network in monitoring animal movement ecology, and to identify the spatial scales that the network effectively operates over. Cluster analyses assessed movements and residency of 2181 in iduals from 92 species, and identified four functional movement classes apparent only through aggregating data across the entire national network. These functional movement classes described movement metrics of in iduals rather than species, and highlighted the plasticity of movement patterns across and within populations and species. Network analyses assessed the utility and redundancy of each component of the national network, revealing multiple spatial scales of connectivity influenced by the geographic positioning of acoustic receivers. We demonstrate the significance of this nationally coordinated network of receivers to better reveal intra-specific differences in movement profiles and discuss implications for effective management.
A water mass classification approach to tracking variability in the East Australian Current
Publisher: Frontiers Media SA
Date: 03-06-2020
Correction: Corrigendum: Cultural traditions across a migratory network shape the genetic structure of southern right whales around Australia and New Zealand
Publisher: Springer Science and Business Media LLC
Date: 04-03-2016
DOI: 10.1038/SREP21875
Abstract: Scientific Reports 5: Article number: 16182 published online: 09 November 2015 updated: 04 March 2016 This Article contains errors. In the Methods section, “Small s les of skin were collected from southern right whales across New Zealand and Australia using a stainless-steel biopsy dart fired from a modified veterinary capture rifle31 or deployed from a crossbow32.
The ocean has depth: two- versus three-dimensional space use estimators in a demersal reef fish
Publisher: Inter-Research Science Center
Date: 31-05-2017
DOI: 10.3354/MEPS12097
Elephant seal foraging success is enhanced in Antarctic coastal polynyas
Publisher: The Royal Society
Date: 26-01-2022
Abstract: Antarctic polynyas are persistent open water areas which enable early and large seasonal phytoplankton blooms. This high primary productivity, boosted by iron supply from coastal glaciers, attracts organisms from all trophic levels to form a rich and erse community. How the ecological benefit of polynya productivity is translated to the highest trophic levels remains poorly resolved. We studied 119 southern elephant seals feeding over the Antarctic shelf and demonstrated that: (i) 96% of seals foraging here used polynyas, with in iduals spending on average 62% of their time there (ii) the seals exhibited more area-restricted search behaviour when in polynyas and (iii) these seals gained more energy (indicated by increased buoyancy from greater fat stores) when inside polynyas. This higher-quality foraging existed even when ice was not present in the study area, indicating that these are important and predictable foraging grounds year-round. Despite these energetic advantages from using polynyas, not all the seals used them extensively. Factors other than food supply may influence an in idual's choice in their use of feeding grounds, such as exposure to predation or the probability of being able to return to distant sub-Antarctic breeding sites.
Genetic differentiation in bottlenose dolphins from South Australia: association with local oceanography and coastal geography
Publisher: Inter-Research Science Center
Date: 2007
DOI: 10.3354/MEPS341265
Strategic allocation of ejaculates by male Adelie penguins
Publisher: The Royal Society
Date: 07-08-2000
Translating Marine Animal Tracking Data into Conservation Policy and Management
Publisher: Elsevier BV
Date: 05-2019
DOI: 10.1016/J.TREE.2019.01.009
Abstract: There have been efforts around the globe to track in iduals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, we compile a broad range of case studies from erse marine taxa to show how tracking data have helped inform conservation policy and management, including reductions in fisheries bycatch and vessel strikes, and the design and administration of marine protected areas and important habitats. Using these ex les, we highlight pathways through which the past and future investment in collecting animal tracking data might be better used to achieve tangible conservation benefits.
ENTANGLEMENT OF CALIFORNIA SEA LIONS AT LOS ISLOTES, BAJA CALIFORNIA SUR, MEXICO
Publisher: Wiley
Date: 1994
Summer foraging behaviour of a generalist predator, the New Zealand fur seal (Arctocephalus forsteri)
Publisher: CSIRO Publishing
Date: 2001
DOI: 10.1071/WR01045
Abstract: This study examined the e behaviour of 20 lactating New Zealand fur seals (Arctocephalus forsteri) breeding at Fuchsia Gully (Ohinepuha, 45˚52S, 170˚44E), Otago Peninsula, New Zealand, over five consecutive austral summers (1993/94–1997/98). We examined annual variation in e behaviour by classifying series of es into e bouts using an iterative statistical technique. We found a non-random pattern of e bouts and bout classification was relatively insensitive to changes in the clustering parameters used. Minimum bouts consisted of at least three es 10 m occurring within a 20-min period. Bouts were classified into three bout types (clusters) using a multi-variate clustering procedure. These clusters described bouts of: (1) long duration with many es of medium depth (LONG) (2) short duration with few, shallow es (SHALLOW) and (3) short duration consisting of long, deep es and long surface intervals and bottom times (DEEP). Diving was primarily nocturnal, and bout type varied significantly with time of day. The proportion of LONG bouts was greatest at dusk and least near dawn, SHALLOW bouts predominated during the night, and DEEP bouts were of importance near dawn. Few es occurred during the day. We detected no annual differences in in idual parameters of e behaviour due to low statistical power. We used randomisation tests to assess whether the proportion of each bout type might vary in years of differing prey consumption, but no significant differences were found. Changes in prey composition were detected in two of these years, which suggests that using the e behaviour of generalist predators to detect changes in resource availability may be a poor option. The high degree of flexibility in foraging behaviour of the New Zealand fur seal means that, inevitably, analyses of e behaviour will have low statistical power. Changes in foraging behaviour may only be useful to detect very large changes in resource availability. Alternatively, very large s le sizes may be able to detect more subtle changes.
Global COVID-19 lockdown highlights humans as both threats and custodians of the environment
Publisher: Elsevier BV
Date: 11-2021
Inter-annual variability in blue whale distribution off southern Sri Lanka between 2011 and 2012
Publisher: MDPI AG
Date: 07-2014
DOI: 10.3390/JMSE2030534
Swimming with whales in Tonga: Sustainable use or threatening process?
Publisher: Elsevier BV
Date: 05-2013
Social olfaction in marine mammals: wild female Australian sea lions can identify their pup's scent
Publisher: The Royal Society
Date: 04-08-2010
Abstract: Historically, anatomical evidence has suggested that marine mammals are anosmic or at best microsmatic, i.e. absent or reduced olfactory capabilities. However, these neuroanatomical considerations may not be appropriate predictors for the use of olfaction in social interactions. Observations suggest that pinnipeds may use olfaction in mother–pup interactions, accepting or rejecting pups after naso-nasal contact. Such maternal–offspring recognition is a favourable area for investigating the involvement of odours in social recognition and selectivity, as females are evolutionarily constrained to direct resources to filial young. However, there is no experimental, morphological or chemical evidence to date for the use of olfaction in social contexts and for in idual odour recognition abilities in pinnipeds. Here, we report unequivocal evidence that Australian sea lion ( Neophoca cinerea ) females can differentiate between the odour of their own pup and that of another, in the absence of any other distinguishing cues. This study demonstrates in idual olfactory recognition in a free-ranging wild mammal and is clear evidence of the social function of olfaction in a marine mammal.
Allosuckling behavior in the Australian sea lion (Neophoca cinerea): An updated understanding
Publisher: Wiley
Date: 29-12-2010
A standardised framework for analysing animal detections from automated tracking arrays
Publisher: Springer Science and Business Media LLC
Date: 12-2018
Effect of climate variability on weaning mass in a declining population of southern elephant seals Mirounga leonina
Publisher: Inter-Research Science Center
Date: 24-03-2017
DOI: 10.3354/MEPS12085
Chemical fingerprints reveal clues to identity, heterozygosity, and relatedness
Publisher: Proceedings of the National Academy of Sciences
Date: 26-08-2015
Low resolution accelerometers can be used to develop time-energy budgets of wild fur seals from captive surrogates
Publisher: PeerJ
Date: 23-02-2018
DOI: 10.7287/PEERJ.PREPRINTS.26570V1
Abstract: Background. Accurate time-energy budgets summarise an animal’s energy expenditure in a given environment and are potentially a sensitive indicator of how an animal responds to changing resources. Deriving accurate time-energy budgets requires a precise measure of time spent in different activities, and an estimate of the energetic cost of that activity. Bio-loggers such as accelerometers may provide a solution for monitoring animals such as fur seals that make long-duration foraging trips over multiple days or weeks. Monitoring such behaviour may require low resolution recording due to the memory constraints of bio-loggers. The aim of this study was to evaluate if accelerometers recording at a low resolution could accurately classify and determine the cost of fur seal activity. Methods. Diving and movement data were collected from nine wild juvenile Australian fur seals equipped with tri-axial accelerometers. To validate time-energy budgets for the fur seals, energy consumption during a range of behaviours was determined from twelve captive surrogates. The time wild fur seals spent in four behavioural states - foraging, grooming, travelling and resting - was quantified with low- and high-resolution data from accelerometers using gradient boosting models (GBM). The daily energy expenditure (DEE) from these four activities was estimated using a relatively simple energetics model developed using their location (land, surface or underwater) and estimates of the energetic cost of each behaviour. Models developed from captive seals were applied to accelerometry data collected from wild juvenile Australian fur seals and their time-energy budgets were reconstructed. Results. Low resolution accelerometery was better at classifying fur seal behaviour over long durations than high resolution accelerometry in captive surrogates. The low resolution model was therefore applied to wild data. This revealed that Juvenile fur seals expended more energy than adults of similar species, but there was no significant difference in DEE across sex or season (winter or summer). Juvenile fur seals used behavioural compensatory techniques to conserve energy during activities that were expected to have high energetic outputs (such as ing). Discussion. Behaviours that are displayed over a long duration can be captured accurately by low-resolution accelerometry and these models can be used to develop time-energy budgets of wild animals. In this study we were able to use such models to monitor juvenile fur seals over multiple foraging trips. This revealed that juvenile fur seals appear to be working energetically harder than their adult counterparts, likely due to the relative novelty of ing and foraging, their smaller body size and the additional cost of growth they sustain. Developing time-energy budgets from accelerometers is an efficient method of estimating energy expenditure from in iduals over time.
Pup production of the New Zealand fur seal on Otago Peninsula, New Zealand
Publisher: Informa UK Limited
Date: 03-1995
Isolation and genetic diversity of endangered grey nurse shark (Carcharias taurus) populations
Publisher: The Royal Society
Date: 03-2006
Abstract: Anthropogenic impacts are believed to be the primary threats to the eastern Australian population of grey nurse sharks ( Carcharias taurus ), which is listed as critically endangered, and the most threatened population globally. Analyses of 235 polymorphic lified fragment length polymorphisms (AFLP) loci and 700 base pairs of mitochondrial DNA control region provide the first account of genetic variation and geographical partitioning (east and west coasts of Australia, South Africa) in C. taurus . Assignment tests, analysis of relatedness and F st values all indicate that the Australian populations are isolated from South Africa, with negligible migration between the east and west Australian coasts. There are significant differences in levels of genetic variation among regions. Australian C. taurus , particularly the eastern population, has significantly less AFLP variation than the other s ling localities. Further, the eastern Australian sharks possess only a single mitochondrial haplotype, also suggesting a small number of founding in iduals. Therefore, historical, rather than anthropogenic processes most likely account for their depauperate genetic variation. These findings have implications for the viability of the eastern Australian population of grey nurse sharks.
The modelling and assessment of whale-watching impacts
Publisher: Elsevier BV
Date: 10-2015
Geographic vocal variation and perceptual discrimination abilities in male Australian sea lions.
Publisher: Springer Science and Business Media LLC
Date: 19-01-2018
DOI: 10.1007/S10071-017-1158-7
Abstract: Vocal characteristics can vary among and within populations. In species with geographic variation in the structure of vocalizations, in iduals may have the ability to discriminate between calls from local and non-local in iduals. The ability to distinguish differences in acoustic signals is likely to have a significant influence on the outcome of social interactions between in iduals, including potentially mate selection and breeding success. Pinnipeds (seals, fur seals, sea lions and walruses) are highly vocal yet the Australian sea lion (Neophoca cinerea) is the only eared seal known to show geographic vocal variation in male barks. Barks are produced in many social interactions and encode sufficient information for both in idual and colony identity to be discriminable. Yet until now, whether males could themselves discriminate these bark differences was unclear. We performed playback experiments in four breeding colonies to investigate whether males can discriminate local from non-local barks. Overall, males responded more strongly to barks from their own colony compared to barks from other colonies regardless of whether those other colonies were close or distant. Competition for females is high in Australian sea lions, but mating periods are asynchronous across colonies. The ability to correctly assess whether a male is from the same colony, thus representing a potential competitor for mates, or merely a visitor from elsewhere, may influence how males interact with others. Given the high cost of fighting, the ability to discern competitors may influence the nature of male-male interactions and ultimately influence how they allocate reproductive effort.
Inter‐ and intrasex habitat partitioning in the highly dimorphic southern elephant seal
Publisher: Wiley
Date: 29-01-2021
DOI: 10.1002/ECE3.7147
Conservation prioritization can resolve the flagship species conundrum
Publisher: Springer Science and Business Media LLC
Date: 24-02-2020
DOI: 10.1038/S41467-020-14554-Z
Abstract: Conservation strategies based on charismatic flagship species, such as tigers, lions, and elephants, successfully attract funding from in iduals and corporate donors. However, critics of this species-focused approach argue it wastes resources and often does not benefit broader bio ersity. If true, then the best way of raising conservation funds excludes the best way of spending it. Here we show that this conundrum can be resolved, and that the flagship species approach does not impede cost-effective conservation. Through a tailored prioritization approach, we identify places containing flagship species while also maximizing global bio ersity representation (based on 19,616 terrestrial and freshwater species). We then compare these results to scenarios that only maximized bio ersity representation, and demonstrate that our flagship-based approach achieves 79−89% of our objective. This provides strong evidence that prudently selected flagships can both raise funds for conservation and help target where these resources are best spent to conserve bio ersity.
Environmental Drivers of Fine-Scale Predator and Prey Spatial Dynamics in Sydney Harbour, Australia, and Adjacent Coastal Waters
Publisher: Springer Science and Business Media LLC
Date: 16-11-2022
DOI: 10.1007/S12237-021-01020-2
Abstract: Greater Sydney is the largest coastal city in Australia and is where bull sharks ( Carcharhinus leucas ) are present every summer and autumn. A decade of acoustic telemetry data was used to identify drivers of space use for bull sharks and their potential prey, according to standardised 6-h intervals using dynamic Brownian bridge movement models. Influences of environmental, physical, and biological variables on the areas of space use, location, and predator–prey co-occurrence were investigated with generalised additive mixed models. Rainfall in the catchment affected space use for all animals (i.e. teleost species and both sexes of sharks), with varying temporal responses. Male sharks responded most promptly to high rainfall moving upstream in 1 day, followed by teleosts (2 to 7 days), and female bull sharks after 4 days. Environmental luminosity affected male shark dispersal and space use, possibly indicating use of visual cues for foraging. Physical characteristics of habitat were important factors driving spatial overlaps between predator and prey in estuarine areas. In sandy embayments 10-m deep, males and female bull sharks overlapped with different species, whereas males and silver trevally ( Pseudocaranx georgianus ) co-occurred in deep holes ( 30 m). Shark size influenced overlap between sexes, with smaller females less likely to co-occur with larger males (~ 50 cm). Variability in space use suggests spatial segregation by sex and size in bull sharks, with in iduals targeting similar prey, yet either in different areas or at different times, ultimately enabling them to exploit different resources when in the same habitats.
Movement responses to environment: fast inference of variation among southern elephant seals with a mixed effects model
Publisher: Wiley
Date: 24-12-2018
DOI: 10.1002/ECY.2566
Abstract: Like many species, movement patterns of southern elephant seals ( Mirounga leonina ) are being influenced by long‐term environmental change. These seals migrate up to 4,000 km from their breeding colonies, foraging for months in a variety of Southern Ocean habitats. Understanding how movement patterns vary with environmental features and how these relationships differ among in iduals employing different foraging strategies can provide insight into foraging performance at a population level. We apply new fast‐estimation tools to fit mixed effects within a random walk movement model, rapidly inferring among‐in idual variability in southern elephant seal environment–movement relationships. We found that seals making foraging trips to the sea ice on or near the Antarctic continental shelf consistently reduced speed and directionality (move persistence) with increasing sea‐ice coverage but had variable responses to chlorophyll a concentration, whereas seals foraging in the open ocean reduced move persistence in regions where circumpolar deep water shoaled. Given future climate scenarios, open‐ocean foragers may encounter more productive habitat but sea‐ice foragers may see reduced habitat availability. Our approach is scalable to large telemetry data sets and allows flexible combinations of mixed effects to be evaluated via model selection, thereby illuminating the ecological context of animal movements that underlie habitat usage.
Environmental drivers of abundance and residency of a large migratory shark, Carcharhinus leucas, inshore of a dynamic western boundary current
Publisher: Inter-Research Science Center
Date: 18-07-2019
DOI: 10.3354/MEPS13052
Vocal identity and species recognition in male Australian sea lions, Neophoca cinerea
Publisher: The Company of Biologists
Date: 15-07-2008
DOI: 10.1242/JEB.013185
Abstract: The acoustic channel is important for communication in otariids (fur seals and sea lions). Discrimination between species, sex or in iduals is essential in communication therefore insight into the role of vocalisations in recognition is vital to understanding otariid social interactions. We measured vocalisations and their use in discriminating sex and species in male Australian sea lions (Neophoca cinerea). Barking calls of mature males were recorded and analysed based on five acoustic parameters. A discriminant function analysis classified calls to the correct in idual at a classification rate of 56%, suggesting that male barking calls are in idually distinctive with the potential to facilitate in idual vocal recognition. Playback experiments were used to assess the role of vocalisations in sex and species recognition both in and out of the breeding season. Males showed significantly stronger reactions to both conspecific and heterospecific males than they did to conspecific females and were most responsive during the breeding season. Australian sea lion males have the most depauperate vocal repertoire of any otariid. This simple repertoire may reflect the ecological circumstances in which these animals breed, with very low colony densities, asynchronous breeding and low levels of polygyny. Yet even in this simple system, males are able to discriminate between males and females of their own species, and distinguish the calls of conspecifics from other species. The barking calls of male Australian sea lions have sufficient information embedded to provide the potential for in idual discrimination and this ability will be assessed in future studies.
Overhauling Ocean Spatial Planning to Improve Marine Megafauna Conservation
Publisher: Frontiers Media SA
Date: 11-2019
Diving deep into trouble: the role of foraging strategy and morphology in adapting to a changing environment
Publisher: Oxford University Press (OUP)
Date: 2020
Abstract: Physiology places constraints on an animal’s ability to forage and those unable to adapt to changing conditions may face increased challenges to reproduce and survive. As the global marine environment continues to change, small, air-breathing, endothermic marine predators such as otariids (fur seals and sea lions) and particularly females, who are constrained by central place foraging during breeding, may experience increased difficulties in successfully obtaining adequate food resources. We explored whether physiological limits of female otariids may be innately related to body morphology (fur seals vs sea lions) and/or dictate foraging strategies (epipelagic vs mesopelagic or benthic). We conducted a systematic review of the increased body of literature since the original reviews of Costa et al. (When does physiology limit the foraging behaviour of freely ing mammals? Int Congr Ser 2004 :359–366) and Arnould and Costa (Sea lions in drag, fur seals incognito: insights from the otariid deviants. In Sea Lions of the World Fairbanks. Alaska Sea Grant College Program, Alaska, USA, pp. 309–324, 2006) on behavioural ( e duration and depth) and physiological (total body oxygen stores and ing metabolic rates) parameters. We estimated calculated aerobic e limit (cADL—estimated duration of aerobic es) for species and used simulations to predict the proportion of es that exceeded the cADL. We tested whether body morphology or foraging strategy was the primary predictor of these behavioural and physiological characteristics. We found that the foraging strategy compared to morphology was a better predictor of most parameters, including whether a species was more likely to exceed their cADL during a e and the ratio of e time to cADL. This suggests that benthic and mesopelagic ers are more likely to be foraging at their physiological capacity. For species operating near their physiological capacity (regularly exceeding their cADL), the ability to switch strategies is limited as the cost of foraging deeper and longer is disproportionally high, unless it is accompanied by physiological adaptations. It is proposed that some otariids may not have the ability to switch foraging strategies and so be unable adapt to a changing oceanic ecosystem.
Chemical Profiles of Integumentary and Glandular Substrates in Australian Sea Lion Pups (Neophoca cinerea)
Publisher: Oxford University Press (OUP)
Date: 25-02-2019
Abstract: Recognition of in iduals or classes of in iduals plays an important role in the communication systems of many mammals. The ability of otariid (i.e., fur seal and sea lion) females to locate and identify their offspring in colonies after returning from regular foraging trips is essential to successful pup rearing. It has been shown that olfaction is used to confirm the identity of the pup by the mother when they reunite, yet the processes by which this chemical recognition occurs remain unclear. Using gas chromatography-mass spectrometry, we examined chemical profiles of integumentary and glandular secretions/excretions from pre- and post-molt Australian sea lion pups (Neophoca cinerea) and compared fur and swab s les to assess data collection methods. Multivariate statistics were applied to assess differences in chemical composition between body regions and sexes. We found differences among secretions from various body regions, driven by the distinctiveness of the oral odor mixture. The fine-scale trends in pre- and post-molt pups seem to differ due to changes in the behavior of pups and consequent decrease in the transfer of compounds among adjacent body regions in older pups. Volatile compounds from exocrine substrates were not distinct for different sexes. We also show that swab s les provide better data for exploring social olfaction than fur s les for this species. Obtaining fundamental chemical information, in this case chemical profiles of animals, and discerning differences in chemical composition is an important step toward fully exploring the intricacies of mother-offspring olfactory recognition and its underlying processes.
Modified Circumpolar Deep Water intrusions in Vincennes Bay, East Antarctica.
Publisher: Wiley
Date: 25-11-2020
Integrating social network analysis and fine-scale positioning to characterize the associations of a benthic shark
Publisher: Elsevier BV
Date: 05-2016
Scaling of Activity Space in Marine Organisms across Latitudinal Gradients
Publisher: University of Chicago Press
Date: 04-2023
DOI: 10.1086/723405
Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf
Publisher: Springer Science and Business Media LLC
Date: 21-07-2023
DOI: 10.1038/S43247-023-00928-W
Abstract: Poor coverage of the Antarctic continental shelf bathymetry impedes understanding the oceanographic processes affecting Antarctica’s role in global climate. Continental shelf bathymetry influences warm modified Circumpolar Deep Water movement onto the shelf, making it an important factor promoting ice shelf melting and influencing the flow of ice shelves into the ocean. Building on previous work using seal es to redefine bathymetry, our longitudinal study of ocean physics and animal behaviour provided new depth information from over 500,000 in idual seal es on the East Antarctic continental shelf. About 25% of these seal es were 220 m (sometimes over 1000 m) deeper than the interpolated seafloor from IBCSO V2. Focusing on four well-s led regions, we show that the bathymetry of 22% to 60% of the s led area was improved by incorporating seal e data. This revealed new bathymetric features, including troughs off the Shackleton Ice Shelf and Underwood Glacier and a deep canyon near the Vanderford Glacier. This deep canyon, the Mirounga-Nuyina Canyon , was confirmed by a recent multi-beam echo sounder survey. Further acquisitions of seal data will improve our understanding and modelling of Antarctic coastal ocean processes and ice-sheet dynamics.
Do wildlife passages act as prey-traps?
Publisher: Elsevier BV
Date: 10-2002
Intrinsic and extrinsic influences on standard metabolic rates of three species of Australian otariid
Publisher: Oxford University Press (OUP)
Date: 2017
Reply to: Shark mortality cannot be assessed by fishery overlap alone
Publisher: Springer Science and Business Media LLC
Date: 07-07-2021
When science places threatened species at risk
Publisher: Wiley
Date: 05-2015
DOI: 10.1111/CONL.12185
Future Directions in Eubalaena spp.: Comparative Research to Inform Conservation
Publisher: Frontiers Media SA
Date: 30-01-2019
Mechanisms for sex-based segregation in foraging behaviour by a polygynous marine carnivore
Publisher: Inter-Research Science Center
Date: 15-08-2019
DOI: 10.3354/MEPS13036
An economical custom-built drone for assessing whale health
Publisher: Frontiers Media SA
Date: 21-12-2017
Genetic and reproductive evidence for two species of ornate wobbegong shark Orectolobus spp. on the Australian east coast
Publisher: Wiley
Date: 11-2008
Individual variation of in-air female 'pup contact' calls in Weddell seals, Leptonychotes weddellii
Publisher: Brill
Date: 2005
Maternal aggression in the South American fur seal in Peru
Publisher: Canadian Science Publishing
Date: 02-1992
DOI: 10.1139/Z92-048
Abstract: Maternal aggression was examined with regard to its role in maternal defense of offspring in the South American fur seal (Arctocephalus australis) at Punta San Juan, Peru (15°22′S, 75°12′W). Female fur seals' responses to conspecifics and to predatory southern sea lions (Otaria byronia) were examined pre- and post-partum. Although the defense of offspring from predators may be expected to be a major component of maternal care, mothers rarely defended their offspring from raiding sea lions, possibly due to the high risks involved in attacking a large and potentially very dangerous predator. The costs of defending the pup from sea lions appeared to outweigh the potential benefit of increased survival of the pup, due to the already high pup mortality at the site. Maternal defense from conspecifics may also be a possible function of female aggression. Females with newborn pups were more aggressive towards other females than were females without pups, particularly during the perinatal attendance period. They threatened a higher proportion of approaching females and won more aggressive encounters postpartum. However, mothers of surviving pups did not appear to be any more aggressive, their pups did not receive any fewer threats from unrelated females, nor did they reside in areas of less aggression, than mothers whose pups died. Aggression towards male conspecifics appeared to serve a further purpose, as females threatened approaching adult and subadult males regardless of whether the females had a pup. Unlike colonially breeding phocid pinnipeds, there seems to be no correlation between increased maternal aggression and neonate survival in the South American fur seal. This may be because females have to leave their offspring to forage when the offspring are still vulnerable to attack by unrelated conspecifics. Alternatively, maternal aggression may have been subjected to such intense selection that although it is responsible for increased pup mortality at the site, there is insufficient variability to measure differential consequences.
Regional variation in trophic ecology of adult female Australian sea lions inferred from stable isotopes in whiskers
Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/WR12181
Abstract: Context The primary selective forces responsible for shaping life-history traits come from the physical and biological environment in which a species resides. Consequently, the limits of a species range may provide a useful measure of adaptive potential to environmental change. The proximity of foraging grounds to terrestrial nursing habitat constrains central-place foragers such as otariid seals in selecting breeding locations. The Australian sea lion (Neophoca cinerea) is an endangered otariid endemic to Australia, whose northern-range extent occurs at a temperate–tropical transition zone on the western coast of Western Australia (WA). Aims Currently, there is a complete absence of data on the foraging ecology of Australian sea lions in WA. We sought to address this critical knowledge gap and provide data on the foraging ecology of adult female Australian sea lions at three isolated breeding colonies in western WA. Methods We used stable-isotope ratios of carbon (δ13C) and nitrogen (δ15N) in the whiskers of pups as proxies to characterise feeding behaviour of 10–28% of all adult female Australian sea lions at each colony. We then compared these geographic data to (1) conspecifics at similar latitude in South Australia (SA) and (2) isotopic data collated from other studies on seabirds that inhabit the region, to place foraging behaviour of adult female Australian sea lions into context. Key results At the southernmost colonies in WA, in idual animals were members of one of two distinct isotopic clusters that could be described by differences in δ15N and δ13C values. In iduals at the northernmost colony displayed δ15N values similar to those of seabirds in the same region. Across the study, isotope ratios of adult female Australian sea lions in western WA were between 3‰ and 5‰ lower than those observed at a colony at similar latitude in SA. Conclusions Gross differences in the physical oceanography between WA and SA may in part explain the differences in isotope ratios of in iduals between the regions, with lower δ15N and δ13C values in WA probably reflecting the relatively depauperate conditions of the Leeuwin Current. Implications Potential regional differences in trophic structure should be considered when developing appropriate management plans for Australian sea lions and regional variation in the diet of Australian sea lion warrants further investigation.
A new genus and species of the frogfish family antennariidae (teleostei: Lophiiformes: Antennarioidei) from New South Wales, Australia, with a diagnosis and key to the genera of the histiophryninae
Publisher: American Society of Ichthyologists and Herpetologists (ASIH)
Date: 12-2014
DOI: 10.1643/CI-13-155
Surfacing characteristics and diving behaviour of blue whales in Sri Lankan waters
Publisher: Elsevier BV
Date: 11-2013
Quantitative diet assessment of wobbegong sharks (genus Orectolobus) in New South Wales, Australia
Publisher: Oxford University Press (OUP)
Date: 21-07-2007
Abstract: Huveneers, C., Otway, N. M., Gibbs, S. E., and Harcourt, R. G. 2007. Quantitative diet assessment of wobbegong sharks (genus Orectolobus) in New South Wales, Australia. – ICES Journal of Marine Science, 64: 1272–1281. The diets of three species of wobbegong (Orectolobus ornatus, O. maculatus, and O. halei) in New South Wales, Australia, were investigated using stomach contents from specimens caught by commercial fishers. Some 80% of wobbegongs caught by commercial setline, and 60% caught by trap or scuba ing, had empty stomachs, most likely due to regurgitation. Wobbegongs were frequently hooked in the stomach (80–90% of the catch), potentially contributing to the greater proportion of empty stomachs compared with other species of shark. The diet of all three species was primarily osteichthyans, but with some cephalopods and chondrichthyans. Interspecific differences in the diets were related to total length of the shark. Octopuses were more frequent in the diet of O. ornatus (dwarf ornate wobbegong) than other wobbegong species, possibly through the smaller adult size facilitating capture of octopuses in small holes/crevices. Orectolobus halei fed more frequently on pelagic species and chondrichthyans, possibly because of their greater mobility. Wobbegongs feed at a high trophic level, and their removal from their ecosystem may impact lower trophic levels.
Widespread utility of highly informative AFLP molecular markers across divergent shark species
Publisher: Oxford University Press (OUP)
Date: 11-2006
Abstract: Population numbers of many shark species are declining rapidly around the world. Despite the commercial and conservation significance, little is known on even the most fundamental aspects of their population biology. Data collection that relies on direct observation can be logistically challenging with sharks. Consequently, molecular methods are becoming increasingly important to obtain knowledge that is critical for conservation and management. Here we describe an lified fragment length polymorphism method that can be applied universally to sharks to identify highly informative genome-wide polymorphisms from 12 primer pairs. We demonstrate the value of our method on 15 ergent shark species within the superorder Galeomorphii, including endangered species which are notorious for low levels of genetic ersity. Both the endangered sand tiger shark (Carcharodon taurus, N = 18) and the great white shark (Carcharodon carcharias, N = 7) displayed relatively high levels of allelic ersity. A total of 59 polymorphic loci (H(e) = 0.373) and 78 polymorphic loci (H(e) = 0.316) were resolved in C. taurus and C. carcharias, respectively. Results from other sharks (e.g., Orectolobus ornatus, Orectolobus sp., and Galeocerdo cuvier) produced remarkably high numbers of polymorphic loci (106, 94, and 86, respectively) from a limited s le size of only 2. A major constraint to obtaining much needed genetic data from sharks is the time-consuming process of developing molecular markers. Here we demonstrate the general utility of a technique that provides large numbers of informative loci in sharks.
VOCAL INDIVIDUALITY OF IN‐AIR WEDDELL SEAL (LEPTONYCHOTES WEDDELLII) PUP “PRIMARY” CALLS
Publisher: Wiley
Date: 12-07-2006
Overcoming multi-year impacts of maternal isotope signatures using multi-tracers and fast turnover tissues in juvenile sharks
Publisher: Elsevier BV
Date: 04-2021
Related Organisations
Univerity Of Cambridge
Location: United Kingdom of Great Britain and Northern Ireland
Related Funding Activities
Linkage Projects - Grant ID: LP110200603
Start Date: 05-2012
End Date: 12-2016
Amount: $225,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0776840
Start Date: 07-2007
End Date: 12-2010
Amount: $120,627.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE100100059
Start Date: 2010
End Date: 12-2010
Amount: $100,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP210103091
Start Date: 07-2021
End Date: 06-2024
Amount: $443,798.00
Funder: Australian Research Council
View Funded ActivitySuper Science Fellowships - Grant ID: FS110200057
Start Date: 01-2012
End Date: 12-2015
Amount: $556,800.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP180101667
Start Date: 07-2018
End Date: 03-2023
Amount: $943,290.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE170100007
Start Date: 2017
End Date: 12-2017
Amount: $552,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP160100162
Start Date: 12-2016
End Date: 09-2022
Amount: $213,445.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0668039
Start Date: 2006
End Date: 12-2006
Amount: $160,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP200100222
Start Date: 03-2021
End Date: 03-2024
Amount: $535,200.00
Funder: Australian Research Council
View Funded Activity