ORCID Profile
0000-0002-9572-1120
Current Organisation
Flinders 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.
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.
Animal Behaviour | Environmental Monitoring | Life Histories | Environmental Science and Management | Evolutionary Biology
Expanding Knowledge in the Biological Sciences | Learner and Learning Processes | Ecosystem Assessment and Management at Regional or Larger Scales |
Publisher: Springer Science and Business Media LLC
Date: 04-08-2021
DOI: 10.1038/S41598-021-94996-7
Abstract: In invasive parasites, generalism is considered advantageous during the initial phase of introduction. Thereafter, fitness costs to parasites, such as host-specific mortality, can drive parasites towards specialism to avoid costly hosts. It is important to determine changes in host specificity of invasive populations to understand host-parasite dynamics and their effects on vulnerable host populations. We examined changes in mortality in the introduced avian v ire fly ( Philornis downsi ) (Diptera: Muscidae), a generalist myasis-causing ectoparasite, between 2004 and 2020 on Floreana Island (Galápagos). Mortality was measured as the proportion of immature larvae found upon host nest termination. Over the time period, the avian v ire fly was most abundant and had low mortality in nests of the critically endangered medium tree finch ( Camarhynchus pauper ) and had the highest mortality in nests of hybrid tree finches ( Camarhynchus spp.). Low larval mortality was also found in small tree ( Camarhynchus parvulus) and small ground finch ( Geospiza fuliginosa) nests. Selection could favour avian v ire flies that select medium tree finch nests and/or avoid hybrid nests. Overall, the finding of differences in avian v ire fly survival across host species is parsimonious with the idea that the introduced fly may be evolving towards host specialisation.
Publisher: BirdLife Australia, Ltd.
Date: 2023
DOI: 10.20938/AFO40049055
Abstract: Adoption is a form of alloparenting in which an in idual raises an unrelated offspring, although it is sometimes unclear whether this behaviour is adaptive or the product of reproductive error. Here, we report an observation of intraspecific adoption in a cooperatively breeding songbird, the Superb Fairy-wren Malurus cyaneus. In a colour-banded population at Cleland Conservation Park, South Australia, a breeding pair with three nutritionally dependent fledglings adopted an additional male fledgling from an adjacent territory. The adoptee was first observed with the new group about 2 weeks after fledging and was regularly fed by his adoptive parents. The fledgling continued to associate with his adoptive group for at least 7 months, even though his natal group remained intact in the adjacent territory. Genetic analyses confirmed that the adopted fledgling was the product of within-pair mating and was not closely related to its adoptive parents. There is some evidence that adult fairy-wrens may discriminate against offspring based on the acoustic structure of their begging calls however, begging calls recorded at the adoptee’s nest were equally similar to incubation calls from both the genetic and adoptive mother. Finally, we discuss similar instances in the literature of intraspecific and interspecific adoption by Superb Fairy-wrens and suggest possible explanations for this behaviour.
Publisher: Elsevier BV
Date: 12-2021
Publisher: Oxford University Press (OUP)
Date: 27-01-2021
DOI: 10.1093/ORNITHAPP/DUAA062
Abstract: As bio-indicators, seabirds across the globe help us understand how our environment is changing, and how this is affecting our wildlife. Little Penguins (Eudyptula minor) in Australia are a key species in understanding the changes to the Australian environment. However, studies generally focus on the effects of oceanic changes without always accounting for the potential interactions with the environmental conditions experienced on land during breeding. This study examined the relationships between both marine and terrestrial environmental variables and breeding success in South Australian Little Penguins, observing 10 colonies over a nonconsecutive 28-yr time period. Our results showed that South Australian Little Penguins had a lower breeding success (fewer fledglings produced per pair) when sea surface temperatures were higher in the 3 mo before breeding and when high winds occurred during the breeding season. We also observed local variation between the colonies: breeding success was only influenced by environmental variables for colonies located near open waters and not for colonies located in enclosed bays. These results confirm the idea that future oceanographic warming is expected to reduce the breeding success (and population size) of some Australian seabirds, including Little Penguins.
Publisher: Oxford University Press (OUP)
Date: 27-05-2017
Publisher: Oxford University Press (OUP)
Date: 07-2020
Publisher: Elsevier BV
Date: 09-2006
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/ZO07072
Abstract: Blood parasites rupture mature red blood cells and so reduce haemoglobin concentration and hence the potential activity levels of infected males. We examined blood parasites and haemoglobin concentration in the superb fairy-wren (Malurus cyaneus) across three years and six locations in South Australia. We tested the prediction that males in nuptial plumage have more blood parasites and hence lower haemoglobin concentration than males in eclipsed plumage. Of 188 birds, 20 (10.6%) had blood parasites (Haemaproteus spp). We found that (1) there was an effect of season and sex on haemoglobin concentration (2) there was no effect of haemoglobin concentration on prevalence of blood parasites or intensity and (3) males in nuptial plumage had more blood parasites but higher haemoglobin concentration than eclipsed males.
Publisher: Springer Science and Business Media LLC
Date: 10-06-2020
Publisher: BirdLife Australia, Ltd.
Date: 2017
DOI: 10.20938/AFO34001009
Publisher: Oxford University Press (OUP)
Date: 04-2016
DOI: 10.1642/AUK-15-162.1
Publisher: Informa UK Limited
Date: 06-10-2023
Publisher: Wiley
Date: 22-05-2022
Abstract: The avian beak is a key morphological trait used for foraging. If parasites alter beak shape, we may expect changes in host foraging behaviour. Larvae of the avian v ire fly Philornis downsi cause naris enlargement in Darwin's finch nestlings when first and second instar larvae consume keratin, blood and tissue from inside the beak of the developing host. This naris malformation persists into adulthood, where nares that are % of total beak length are considered enlarged. We measured effects of parasite‐induced naris enlargement on foraging behaviour, foraging niche overlap and body condition in Darwin's finches on Floreana Island. Foraging behaviour was ranked by the stress per foraging technique exerted on the beak and ranged from least stress for ‘gleaning’ to most stress for ‘chip off bark’. Naris enlargement occurred in 34% of adult birds. The most common foraging technique differed among species: medium tree finches ( Camarhynchus pauper ) often chipped off bark to extract subsurface prey, small tree finches ( C. parvulus ) often gleaned surface prey from foliage, hybrids gleaned prey from bark and foliage, and small ground finches ( Geospiza fuliginosa ) mostly foraged on the ground. In C. pauper , birds with naris enlargement did more gleaning and less subsurface prey excavation. Foraging niche across species was most similar in birds with naris enlargement. Finally, body condition was lower in insectivorous tree finches with malformed beaks. A novel aspect of this study is the idea that parasite‐induced alterations to phenotype affect ecological processes and interspecific interactions at large temporal and spatial scales. The parasitism occurs early in life but the ecological effects of this parasitism, if causative, are happening later. Read the free Plain Language Summary for this article on the Journal blog.
Publisher: Informa UK Limited
Date: 12-2009
DOI: 10.1071/MU09035
Publisher: Springer Science and Business Media LLC
Date: 09-02-2019
Publisher: Springer Science and Business Media LLC
Date: 29-11-2010
Publisher: Frontiers Media SA
Date: 06-05-2016
Publisher: Springer Science and Business Media LLC
Date: 29-10-2018
Publisher: Springer Science and Business Media LLC
Date: 28-02-2023
DOI: 10.1007/S10531-023-02557-3
Abstract: Investigating the ecology of a species and the spatial requirements needed for their survival within an environment can improve and help develop conservation measures. In this study, we reviewed the literature describing the importance of fine-scale landscape characteristics on the distribution of penguin species. We then investigated little penguin nest-site use across eleven colonies in South Australia, with a focus on nest type, vegetation cover, nest entrance orientation, proximity to the nearest active nest, and side of the island. We showed that both abiotic and biotic variables were important for nest-site use in penguins and that the specific variables varied between species and populations. Little penguins in South Australia did not appear to use nest sites randomly, and active nests were mostly found on the northern side of the island and facing east or west. Our study highlights the importance of gaining a better understanding of penguin nest-site use, and their fitness consequences for populations, to ensure effective conservation outcomes.
Publisher: The Royal Society
Date: 05-2014
Abstract: Superb fairy-wren ( Malurus cyaneus ) females use an incubation call to teach their embryos a vocal password to solicit parental feeding care after hatching. We previously showed that high call rate by the female was correlated with high call similarity in fairy-wren chicks, but not in cuckoo chicks, and that parent birds more often fed chicks with high call similarity. Hosts should be selected to increase their defence behaviour when the risk of brood parasitism is highest, such as when cuckoos are present in the area. Therefore, we experimentally test whether hosts increase call rate to embryos in the presence of a singing Horsfield's bronze-cuckoo ( Chalcites basalis ). Female fairy-wrens increased incubation call rate when we experimentally broadcast cuckoo song near the nest. Embryos had higher call similarity when females had higher incubation call rate. We interpret the findings of increased call rate as increased teaching effort in response to a signal of threat.
Publisher: Elsevier BV
Date: 11-2022
Publisher: Springer Science and Business Media LLC
Date: 09-06-2010
Publisher: Oxford University Press (OUP)
Date: 17-10-2017
Publisher: Springer Science and Business Media LLC
Date: 13-07-2023
DOI: 10.1007/S10336-023-02093-5
Abstract: Nesting success tends to increase with age in birds, in part because older birds select more concealed nest sites based on experience and/or an assessment of prevailing predation risk. In general, greater plant ersity is associated with more bio ersity and more vegetation cover. Here, we ask if older Darwin’s finch males nest in areas with greater vegetation cover and if these nest sites also have greater avian species ersity assessed using song. We compared patterns in Darwin’s Small Tree Finch ( Camarhynchus parvulus ) and Darwin’s Small Ground Finch ( Geospiza fuliginosa ) as males build the nest in both systems. We measured vegetation cover, nesting height, and con- vs. heterospecific songs per minute at 55 nests (22 C. parvulus , 33 G. fuliginosa ). As expected, in both species, older males built nests in areas with more vegetation cover and these nests had less predation. A novel finding is that nests of older males also had more heterospecific singing neighbors. Future research could test whether older males outcompete younger males for access to preferred nest sites that are more concealed and sustain a greater local bio ersity. The findings also raise questions about the ontogenetic and fitness consequences of different acoustical experiences for developing nestlings inside the nest.
Publisher: Springer Science and Business Media LLC
Date: 27-09-2023
Publisher: Frontiers Media SA
Date: 27-04-2023
DOI: 10.3389/FEVO.2023.1034941
Abstract: Human-altered landscapes may act as an environmental filter benefiting species or in iduals with specific sets of capacities or behaviors. Yet the effects of human activity on culturally transmitted traits in animals are still poorly understood. Combining song recordings and simulated territory intrusions, we investigated whether songs (a cultural trait) and aggressiveness (a personality trait) in small ground finches ( Geospiza fuliginosa ) differed along a gradient of human activity levels (high-low-high) spanning two habitats with contrasting levels of rainfall (arid lowlands, humid highlands). We found that more common syllable types were more prevalent in arid lowland sites and at sites with high human activity. The number of syllables per song, song duration, song tempo and song rhythmicity did not differ across habitats or levels of human activity. During simulated territorial intrusions, small ground finches living in areas with higher levels of human activity and in the arid lowlands (regardless of human activity) showed the strongest aggressive response compared to those living in areas with lower levels of human activity or in the humid highlands. Thus, prevalence of aggression and syllable commonness correlated with each other across sites. Our results support the idea that resource distribution and human-impacted environments may select jointly for specific behavioral phenotypes such as aggression as well as common cultural traits.
Publisher: IntechOpen
Date: 23-09-2020
Publisher: PeerJ
Date: 28-09-2022
DOI: 10.7717/PEERJ.14011
Abstract: Personality syndromes in animals may have adaptive benefits for survival. For ex le, while engaging in predator deterrence, reactive in iduals tend to prioritise their own survival, while proactive in iduals engage in riskier behaviours. Studies linking animal personality measured in captivity with in idual fitness or behaviours in the wild are sparse, which is a gap in knowledge this study aims to address. We used playback experiments in superb fairy-wrens ( Malurus cyaneus ), a common Australian songbird with a cooperative breeding system, to assess whether three personality traits measured during short-term captivity correlated with behavioural responses in the wild to a perceived nest and adult predator, the grey currawong ( Strepera versicolor ). We used three standard measures of personality in birds: struggle responses to human handling (boldness), exploration during a novel environment test, and aggressiveness during a mirror presentation. Superb fairy-wrens showed a significantly stronger response to the predator playback than to the control (willie wagtail, Rhipidura leucophrys ) playback, suggesting that they recognised the predator playback as a threat without any accompanying visual stimulus. Birds that attacked their mirror image during the mirror presentation and those that spent a moderate amount of time close to the mirror responded more strongly to predator playback (by approaching the speaker faster and closer, spending more time near the speaker, and being more likely to alarm call) compared to those with low aggressiveness or those that spent very short or long durations close to the mirror. Neither boldness nor exploration in the novel environment test predicted playback response. Our results align with a growing number of studies across species showing the importance of animal personalities as factors for fitness and survival.
Publisher: The Royal Society
Date: 06-09-2021
Abstract: Understanding when learning begins is critical for identifying the factors that shape both the developmental course and the function of information acquisition. Until recently, sufficient development of the neural substrates for any sort of vocal learning to begin in songbirds was thought to be reached well after hatching. New research shows that embryonic gene activation and the outcome of vocal learning can be modulated by sound exposure in ovo . We tested whether avian embryos across lineages differ in their auditory response strength and sound learning in ovo , which we studied in vocal learning (Maluridae, Geospizidae) and vocal non-learning (Phasianidae, Spheniscidae) taxa. While measuring heart rate in ovo , we exposed embryos to (i) conspecific or heterospecific vocalizations, to determine their response strength, and (ii) conspecific vocalizations repeatedly, to quantify cardiac habituation, a form of non-associative learning. Response strength towards conspecific vocalizations was greater in two species with vocal production learning compared to two species without. Response patterns consistent with non-associative auditory learning occurred in all species. Our results demonstrate a capacity to perceive and learn to recognize sounds in ovo , as evidenced by habituation, even in species that were previously assumed to have little, if any, vocal production learning. This article is part of the theme issue ‘Vocal learning in animals and humans’.
Publisher: Wiley
Date: 26-12-2009
Publisher: Wiley
Date: 24-01-2013
Publisher: Wiley
Date: 12-03-2023
DOI: 10.1111/IBI.13201
Abstract: While automated recorders are becoming a favourable tool to monitor birds, methods to analyse the large amount of data generated and their reliability for estimating population size are still limited. In this study, I compared Little Penguins Eudyptula minor call detection between a trained researcher, amateur volunteers and an automated software, assessed which environmental factors affect call variability and detectability and determined the feasibility of automated recorders to estimate population sizes. I found that (1) the number of calls detected by the trained researcher was significantly higher than those detected by the amateur volunteers and automated software, (2) neither wind speed nor moon illumination affected call variability and detectability, and (3) six automated recorders estimated between 3% (large colony) and 14–26% (small colony) of the population. This study contributes to our understanding of the efficacy of automated recorders for avian monitoring.
Publisher: The Royal Society
Date: 15-12-2021
Abstract: Selection should act on parental care and favour parental investment decisions that optimize the number of offspring produced. Such predictions have been robustly tested in predation risk contexts, but less is known about alternative functions of parental care under conditions of parasitism. The avian v ire fly ( Philornis downsi ) is a myasis-causing ectoparasite accidentally introduced to the Galápagos Islands, and one of the major mortality causes in Darwin's finch nests. With an 11-year dataset spanning 21 years, we examine the relationship between parental care behaviours and number of fly larvae and pupae in Darwin's finch nests. We do so across three host species ( Camarhynchus parvulus , C. pauper , Geospiza fuliginosa ) and one hybrid Camarhynchus group. Nests with longer female brooding duration (minutes per hour spent sitting on hatchlings to provide warmth) had fewer parasites, and this effect depended on male food delivery to chicks. Neither male age nor number of nest provisioning visits were directly associated with number of parasites. While the causal mechanisms remain unknown, we provide the first empirical study showing that female brooding duration is negatively related to the number of ectoparasites in nests. We predict selection for coordinated host male and female behaviour to reduce gaps in nest attendance, especially under conditions of novel and introduced ectoparasites.
Publisher: Elsevier BV
Date: 09-2016
Publisher: Springer Science and Business Media LLC
Date: 20-11-2022
DOI: 10.1007/S00436-021-07350-1
Abstract: Understanding the range and behaviour of an invasive species is critical to identify key habitat areas to focus control efforts. Patterns of range use in parasites can differ temporally, across life stages and between sexes. The invasive avian v ire fly, Philornis downsi , spends the larval stage of its life within bird nests, feeding on developing nestlings and causing high levels of mortality and deformation. However, little is known of the ecology and behaviour of the non-parasitic adult fly life stage. Here, we document sex-specific temporal and spatial patterns of abundance of adult avian v ire flies during a single Darwin’s finch breeding season. We analyse fly trapping data collected across 7 weeks in the highlands ( N = 405 flies) and lowlands ( N = 12 flies) of Floreana Island (Galápagos). Lowland catches occurred later in the season, which supports the hypothesis that flies may migrate from the food-rich highlands to the food-poor lowlands once host breeding has commenced. Fly abundance was not correlated with host nesting density (oviposition site) but was correlated with distance to the agricultural zone (feeding site). We consistently caught more males closer to the agricultural zone and more females further away from the agricultural zone. These sex differences suggest that males may be defending or lekking at feeding sites in the agricultural zone for mating. This temporal and sex-specific habitat use of the avian v ire fly is relevant for developing targeted control methods and provides insight into the behavioural ecology of this introduced parasite on the Galápagos Archipelago.
Publisher: Springer Science and Business Media LLC
Date: 09-07-2011
Publisher: CSIRO Publishing
Date: 2015
DOI: 10.1071/MF14098
Abstract: Over the past decade, populations of little penguins (Eudyptula minor) have been seriously declining across South Australia for reasons still not fully understood. In the present study, I investigated breeding performance and return rates of little penguins on Granite Island for 17 years in relation to patterns of population decline. I focussed on the impacts of human disturbance, breeding site, abandonment and predation on breeding success. The average breeding success was 1.05±0.12 fledglings per pair and breeding success increased since 1990, despite population decline. Breeding site was the main factor affecting breeding success. I found no effect of predation or abandonment on breeding success, but there was a negative effect of predation on the number of dead chicks found. In addition, I found a negative effect of human disturbance. Despite the observed increase in breeding success, return rates were extremely low for both adults (16.3%) and fledglings (2.3%). Population modelling confirmed the observed population decline on Granite Island, with subadult survival being the most critical variable affecting population growth. The present study thus highlighted the need for further studies into factors affecting survival of adults and subadults.
Publisher: The Royal Society
Date: 22-12-2014
Abstract: Embryos were traditionally considered to possess limited learning abilities because of the immaturity of their developing brains. By contrast, neonates from erse species show behaviours dependent on prior embryonic experience. Stimulus discrimination is a key component of learning and has been shown by a handful of studies in non-human embryos. Superb fairy-wren embryos ( Malurus cyaneus ) learn a vocal password that has been taught to them by the attending female during incubation. The fairy-wren embryos use the learned element as their begging call after hatching to solicit more parental feeding. In this study, we test whether superb fairy-wren embryos have the capacity to discriminate between acoustical stimuli and whether they show non-associative learning. We measured embryonic heart rate response using a habituation/dishabituation paradigm with eggs sourced from nests in the wild. Fairy-wren embryos lowered their heart rate in response to the broadcasts of conspecific versus heterospecific calls, and in response to the calls of novel conspecific in iduals. Thus, fairy-wrens join humans as vocal-learning species with known prenatal learning and in idual discrimination.
Publisher: Informa UK Limited
Date: 03-2009
DOI: 10.1071/MU08048
Publisher: Elsevier BV
Date: 11-2012
DOI: 10.1016/J.CUB.2012.09.025
Abstract: How do parents recognize their offspring when the cost of making a recognition error is high? Avian brood parasite-host systems have been used to address this question because of the high cost of parasitism to host fitness. We discovered that superb fairy-wren (Malurus cyaneus) females call to their eggs, and upon hatching, nestlings produce begging calls with key elements from their mother's "incubation call." Cross-fostering experiments showed highest similarity between foster mother and nestling calls, intermediate similarity with genetic mothers, and least similarity with parasitic Horsfield's bronze-cuckoo (Chalcites basalis) nestlings. Playback experiments showed that adults respond to the begging calls of offspring hatched in their own nest and respond less to calls of other wren or cuckoo nestlings. We conclude that wrens use a parent-specific password learned embryonically to shape call similarity with their own young and thereby detect foreign cuckoo nestlings.
Publisher: Wiley
Date: 25-03-2021
DOI: 10.1111/JEB.13783
Abstract: Empirical data that identify contemporary mechanisms of ergence shed light on how species could multiply. In this study, we measured population genetic structure, song syllable ersity and response to simulated intruder song in Darwin's small tree finch ( Camarhynchus parvulus ) on Santa Cruz and Floreana Islands, Galápagos archipelago. Our aim was to test whether the magnitude of contemporary behavioural response in resident birds was consistent with patterns of genetic or cultural differences between populations. We analysed genetic structure and the occurrence of song syllable types, and experimentally measured the response of resident birds to intruder bird song from different geographical origin (i.e., island) or syllable type. We discovered a weak signal of population genetic structure between Santa Cruz and Floreana Islands. Although some song syllables occurred on both islands, others were unique to each island Santa Cruz Island males used more unique syllables than Floreana Island males. Both Santa Cruz and Floreana resident males discriminated their response towards a simulated intruder song based on the geographical origin of the intruder song, but not on the syllable type sung by the intruder. We conclude that the populations are erging in genetic and cultural traits and identified a signal of contemporary behavioural response that could maintain ergence upon secondary contact.
Publisher: Brill
Date: 28-06-2023
DOI: 10.1163/1568539X-BJA10224
Abstract: Personality traits can remain consistent throughout adult life, but it is less clear when these behavioural differences first arise and whether they are maintained across ontogenetic stages. We measured personality across three life stages (nestling, fledgling, and adult) in a wild population of superb fairy-wrens ( Malurus cyaneus ). We assessed (1) boldness (response to human handling, at all three stages), (2) exploration (response to a novel environment, in fledglings and adults) and (3) aggressiveness (response to mirror-image stimulation, in fledglings and adults). Personality differences were often consistent within life stages but never across them: specifically, aggressiveness was repeatable in fledglings and all three traits were repeatable in adults. We had insufficient statistical evidence for the presence of behavioural syndromes between any of our three personality traits, either at the fledgling or adult stages. Our results suggest that long-term personality traits may not become entrenched until adulthood in this species.
Publisher: Frontiers Media SA
Date: 31-05-2022
DOI: 10.3389/FMARS.2022.875259
Abstract: Droughts in many regions of the world are increasing in frequency and severity which, coupled with effects from anthropogenic water extraction and ersion, are reducing river discharges. Yet to date, few studies have investigated the impacts of hydrological droughts (i.e., reduced river outflows to the ocean) on seabirds. Here, we examined the consequences of the “Millennium Drought” on the local decline of an iconic Australian seabird, the little penguin ( Eudyptula minor ). We analysed monthly and annual penguin numbers in relation to river outflow, rainfall, the characteristics of the coastal waters (sea surface temperatures and chlorophyll- a concentrations), and local abundance of key predators and prey species. We found a negative association between monthly penguin numbers and both sea surface temperatures and river outflow. Annual penguin numbers were positively associated with southern garfish numbers (our local indicator of food availability) but negatively associated with annual chlorophyll- a concentrations. Our findings emphasizing the need for further research into the effect of hydrological droughts on seabird populations and for improved river management that account for potential downstream impacts on the coastal environment receiving freshwater from rivers.
Publisher: Springer Science and Business Media LLC
Date: 22-05-2013
Abstract: Risk assessment occurs over different temporal and spatial scales and is selected for when in iduals show an adaptive response to a threat. Here, we test if birds respond to the threat of brood parasitism using the acoustical cues of brood parasites in the absence of visual stimuli. We broadcast the playback of song of three brood parasites ( Chalcites cuckoo species) and a sympatric non-parasite (striated thornbill, Acanthiza lineata ) in the territories of superb fairy-wrens ( Malurus cyaneus ) during the peak breeding period and opportunistic breeding period. The three cuckoo species differ in brood parasite prevalence and the probability of detection by the host, which we used to rank the risk of parasitism (high risk, moderate risk, low risk). Host birds showed the strongest response to the threat of cuckoo parasitism in accordance with the risk of parasitism. Resident wrens had many alarm calls and close and rapid approach to the playback speaker that was broadcasting song of the high risk brood parasite (Horsfield’s bronze-cuckoo, C. basalis ) across the year (peak and opportunistic breeding period), some response to the moderate risk brood parasite (shining bronze-cuckoo, C. lucidus ) during the peak breeding period, and the weakest response to the low risk brood parasite (little bronze-cuckoo, C. minutillus ). Playback of the familiar control stimulus in wren territories evoked the least response. Host response to the threat of cuckoo parasitism was assessed using vocal cues of the cuckoo and was predicted by the risk of future parasitism.
Publisher: Springer Science and Business Media LLC
Date: 15-10-2023
DOI: 10.1007/S10530-022-02935-Y
Abstract: Due to novel or dynamic fluctuations in environmental conditions and resources, host and parasite relationships can be subject to erse selection pressures that may lead to significant changes during and after invasion of a parasite. Genomic analyses are useful for elucidating evolutionary processes in invasive parasites following their arrival to a new area and host. Philornis downsi (Diptera: Muscidae), the avian v ire fly, was introduced to the Galápagos Islands circa 1964 and has since spread across the archipelago, feeding on the blood of developing nestlings of endemic land birds. Since its discovery, there have been significant changes to the dynamics of P. downsi and its novel hosts, such as shifting mortality rates and changing oviposition behaviour, however no temporal genetic studies have been conducted. We collected P. downsi from nests and traps from a single island population over a 14-year period, and genotyped flies at 469 single nucleotide polymorphisms (SNPs) using restriction-site associated DNA sequencing (RADSeq). Despite significant genetic differentiation (F ST ) between years, there was no evidence for genetic clustering within or across four s ling years between 2006 and 2020, suggesting a lack of population isolation. Sibship reconstructions from P. downsi collected from 10 Darwin’s finch nests s led in 2020 showed evidence for shifts in reproductive behaviour compared to a similar genetic analysis conducted in 2004–2006. Compared with this previous study, females mated with fewer males, in idual females oviposited fewer offspring per nest, but more unique females oviposited per nest. These findings are important to consider within reproductive control techniques, and have fitness implications for both parasite evolution and host fitness.
Publisher: Springer Science and Business Media LLC
Date: 18-07-2023
DOI: 10.1038/S41598-023-38493-Z
Abstract: Urbanisation is occurring around the world at a rapid rate and is generally associated with negative impacts on bio ersity at local, regional, and global scales. Examining the behavioural response profiles of wildlife to urbanisation helps differentiate between species that do or do not show adaptive responses to changing landscapes and hence are more or less likely to persist in such environments. Species-specific responses to urbanisation are poorly understood in the Southern Hemisphere compared to the Northern Hemisphere, where most of the published literature is focussed. This is also true for raptors, despite their high ersity and comparably high conservation concern in the Southern Hemisphere, and their critical role within ecosystems as bioindicators of environmental health. Here, we explore this knowledge gap using community science data sourced from eBird to investigate the urban tolerance of 24 Australian raptor species at a continental scale. We integrated eBird data with a global continuous measure of urbanisation, artificial light at night (ALAN), to derive an urban tolerance index, ranking species from positive to negative responses according to their tolerance of urban environments. We then gathered trait data from the published literature to assess whether certain traits (body mass, nest substrate, habitat type, feeding guild, and migratory status) were associated with urban tolerance. Body size was negatively associated with urban tolerance, as smaller raptors had greater urban tolerance than larger raptors. Out of the 24 species analysed, 13 species showed tolerance profiles for urban environments (positive response), and 11 species showed avoidance profiles for urban environments (negative response). The results of this study provide impetus to conserve native habitat and improve urban conditions for larger-bodied raptor species to conserve Australian raptor ersity in an increasingly urbanised world.
Publisher: Wiley
Date: 10-02-2021
DOI: 10.1111/IBI.12925
Abstract: Species that are constantly exposed to disturbances, such as human disturbance or non‐lethal contacts with predators or conspecifics, can experience chronic stress. Within a species range, variation in the frequency and predictability of such disturbances can lead to population differences in stress responses. Here, we investigated the stress response of Little Penguins Eudyptula minor to an introduced predator and a conspecific at two South Australian colonies that differed in habitat, conspecific density, levels of human disturbance and predation risk (high, low). We used playback experiments of Cat Felis catus or Little Penguin calls and recorded the behaviour and physiological (heart rate) response of adults in relation to playback type (Cat, Penguin) as well as habitat characteristics (habitat type, nest type, nest visibility) and number of conspecifics present. Our results showed that in iduals from the high‐disturbance colony (also living in a mixed habitat with fewer neighbours) exhibited higher vigilance and heart rate responses than in iduals from the low‐disturbance colony (living in a closed habitat with a high number of neighbours). Our results highlight that guidelines for managing penguin species cannot be generalized across populations and need to be colony‐specific.
Publisher: Wiley
Date: 08-11-2017
DOI: 10.1111/MEC.14385
Abstract: Extra-pair paternity (EPP), where offspring are sired by a male other than the social male, varies enormously both within and among species. Trying to explain this variation has proved difficult because the majority of the interspecific variation is phylogenetically based. Ideally, variation in EPP should be investigated in closely related species, but clades with sufficient variation are rare. We present a comprehensive multifactorial test to explain variation in EPP among in iduals in 20 populations of nine species over 89 years from a single bird family (Maluridae). Females had higher EPP in the presence of more helpers, more neighbours or if paired incestuously. Furthermore, higher EPP occurred in years with many incestuous pairs, populations with many helpers and species with high male density or in which males provide less care. Altogether, these variables accounted for 48% of the total and 89% of the interspecific and interpopulation variation in EPP. These findings indicate why consistent patterns in EPP have been so challenging to detect and suggest that a single predictor is unlikely to account for the enormous variation in EPP across levels of analysis. Nevertheless, it also shows that existing hypotheses can explain the variation in EPP well and that the density of males in particular is a good predictor to explain variation in EPP among species when a large part of the confounding effect of phylogeny is excluded.
Publisher: The Royal Society
Date: 08-2017
Abstract: Early environmental enrichment improves postnatal cognition in animals and humans. Here, we examined the effects of the prenatal acoustic environment (parental song rate) on prenatal attention in superb fairy-wren ( Malurus cyaneus ) embryos, the only songbird species with evidence of prenatal discrimination of maternal calls and in ovo call learning. Because both adults also sing throughout the incubation phase, we broadcast songs to embryos and measured their heart rate response in relation to parental song rate and tutor identity (familiarity, sex). Embryos from acoustically active families (high parental song rate) had the strongest response to songs. Embryos responded (i) strongest to male songs irrespective of familiarity with the singer, and (ii) strongest if their father had a high song rate during incubation. This is the first evidence for a prenatal physiological response to particular songs (potential tutors) in the egg, in relation to the prenatal acoustic environment, and before the sensitive period for song learning.
Publisher: Wiley
Date: 25-04-2023
DOI: 10.1111/IBI.13217
Abstract: The presence of humans within the natural environment is increasing worldwide. Assessing the impact of such activities on wildlife is crucial for declining populations where human disturbance adds to existing pressures. Here, we investigated how human activities at night influenced Little Penguin Eudyptula minor numbers and behaviours (specifically return time, number of vocalizations and time spent in vigilance) on Granite Island, a declining population in South Australia, Australia. We combined data from regular night surveys with continuous video and audio monitoring to assess the impact of human activities on the Little Penguins. The use of white light (i.e. from torches or camera flashes) by people was the most frequent activity recorded at night (recorded on 65% of the monitored nights). Fewer penguins were found on land at night when Dogs Canis lupus familiaris were present, but not when the number of people increased, when concerts occurred, or when white lights were used. Little Penguins were observed more often returning late from sea at night when Dogs were present and when white lights were used, but not when concerts occurred. An increase in penguin vocalizations at night correlated with the presence of Dogs and the occurrence of concerts, whereas penguins vocalized less when white lights were used. The time Little Penguins spent in vigilance did not correlate with any of the disturbances analysed. Our study also highlights the impact of coronavirus disease 2019 (COVID‐19) on wildlife, as the occurrence of human activities increased significantly following the implementation of the COVID‐19 health protection measures. These results add to a growing body of literature suggesting that human activities on land, and their consequent disturbance(s), may affect the numbers and behaviours of wildlife and that appropriate measures need to be developed to limit such impacts.
Publisher: Informa UK Limited
Date: 09-2013
DOI: 10.1071/MU12066
Publisher: Oxford University Press (OUP)
Date: 31-07-2021
DOI: 10.1093/BIOLINNEAN/BLAB092
Abstract: Although in-nest parasitism can reduce the fitness of avian hosts, the severity of these effects may vary with host physiology and behaviour. If certain nestling behaviours are beneficial for resisting parasitism, then selection may favour some behavioural phenotypes over others. Here, we tested whether differences in nestling behaviour mediate the negative effects of parasitism, using small ground finches (Geospiza fuliginosa), on Floreana Island, that had been parasitized by the invasive avian v ire fly (Philornis downsi). We first established, using 4 years of breeding data (2005, 2006, 2010 and 2020), that nestlings exposed to more parasites had larger nares and, among older nestlings only, lower body mass. We then examined, using data from the 2020 season, whether each nestling’s behaviour (specifically, its response to human handling) predicted the severity of its naris deformation. When faced with high-intensity parasitism, more responsive nestlings (i.e. those that struggled more during handling) had larger nares compared to more docile nestlings. This suggests that more responsive nestlings suffer greater fitness costs due to parasitism, although we also discuss alternative explanations. Future work should consider the stability and heritability of these nestling behavioural differences and whether parasite-induced selection shapes behavioural variation at the population level.
Publisher: Wiley
Date: 11-10-2016
DOI: 10.1002/ECE3.2516
Publisher: Brill
Date: 2010
Publisher: Oxford University Press (OUP)
Date: 2018
DOI: 10.1642/AUK-17-75.1
Publisher: CSIRO Publishing
Date: 20-04-2023
DOI: 10.1071/MF22138
Abstract: Context Seabirds are important bio-indicators that play an important role in nutrient cycling within coastal communities. Yet, the impact of anthropogenic noises produced from coastal developments across seabird species has received little attention. To create more refined and effective mitigation strategies, a better understanding of how different seabird species and in iduals respond to anthropogenic noise is required. Aims This study aimed to assess how in idual seabirds respond to noises resulting from coastal development (construction noises). Methods We investigated the behavioural (vigilance, distress) and physiological (heart rate) responses of little penguins (Eudyptula minor) to experimental playback of construction noises and the potential impacts of construction noises on breeding success. Key results Little penguins spent significantly more time in vigilance (but showed no increase in heart rate) during the construction noise playback than they did during the control. Nests exposed to the noise experiment were more likely to produce at least one fledgling compared with those that were not. Conclusions and implications Our results support the distracted prey hypothesis, which over long periods may reduce the time in iduals spend performing biologically important behaviours and increase predation risk.
Publisher: Elsevier BV
Date: 07-2023
Start Date: 03-2019
End Date: 06-2022
Amount: $385,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 07-2022
End Date: 06-2024
Amount: $145,132.00
Funder: Australian Research Council
View Funded Activity