ORCID Profile
0000-0003-2620-2826
Current Organisation
Murdoch University
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Publisher: Wiley
Date: 13-04-2010
DOI: 10.1111/J.1095-8649.2010.02615.X
Abstract: In this study, 1429 fishes of 18 different species (12 native and six exotic) were s led from 29 localities to compare the levels of parasitism between native and exotic fish species and to examine the relationship between environmental degradation and parasite ersity. Forty-four putative species of parasites were found and most of these appear to be native parasites, which have not previously been described. Two parasite species, Lernaea cyprinacea and Ligula intestinalis, are probably introduced. Both were found on or in a range of native fish species, where they may cause severe disease. Levels of parasitism and parasite ersity were significantly greater in native fishes than in exotic species, and this may contribute to an enhanced demographic performance and competitive ability in invading exotics. Levels of parasitism and parasite ersity in native fishes were negatively related to habitat disturbance, in particular to a suite of factors that indicate increased human use of the river and surrounding environment. This was due principally to the absence in more disturbed habitats of a number of species of endoparasites with complex life cycles, involving transmission between different host species.
Publisher: Wiley
Date: 28-01-2016
Publisher: Wiley
Date: 07-06-2023
DOI: 10.1002/ECO.2566
Abstract: Crayfish perform important roles within freshwater ecosystems, including in regions where global warming is causing prolonged drying of waterbodies. However, little is known about responses of crayfish to habitat drying from both a behavioural and physiological perspective. We compared burrowing ability, survival and metabolism of the crayfish Cherax quinquecarinatus from a seasonal stream and a perennial stream. Burrowing ability and crayfish survival were quantified in a mesocosm experiment contrasting sediment type (sand vs. clay/sand mixture) and water regime. Aerobic scope, standard metabolic rate (SMR) and maximum metabolic rate (MMR) were also compared using intermittent flow respirometry. Crayfish from the seasonal stream showed limited burrowing ability but higher survival in the drying treatment, while the perennial stream crayfish burrowed strongly in the clay/sand sediment. Higher survival suggests that crayfish from seasonal streams might be physiologically better adapted to drying. Larger crayfish burrowed more proficiently, reaching the saturated hyporheic zone refuge in the clay/sand sediment treatment. SMR/MMR/aerobic scope did not differ between populations or respirometry runs however, SMR differed between in iduals, perhaps due to personality traits. There was a significant negative relationship between MMR/aerobic scope and weight. Sediment type may limit C. quinquecarinatus burrowing and persistence through drying. Crayfish populations did not differ in terms of metabolism however, crayfish from seasonal habitats may possess more efficient physiological adaptations to drying. This study highlights the need for greater research attention on the effects of climatic drying on both the behaviour and the physiology of species exposed to climate change.
Publisher: Elsevier BV
Date: 08-2014
Publisher: Wiley
Date: 18-04-2021
DOI: 10.1002/AQC.3578
Abstract: Sawfishes (Family: Pristidae) are one of the most imperilled fish families worldwide. There is an increasingly urgent need to better understand the biology, ecology, and population status of the five sawfish species to develop more effective conservation measures. The dwarf sawfish, Pristis clavata , is one of the least researched members of the pristids, with literature limited to analysing disparate datasets or collations of rare encounters in northern Australia. This study examined the spatial ecology of dwarf sawfish using targeted surveys and acoustic telemetry to determine its habitat use in a macrotidal estuary in northern Australia. Seventeen dwarf sawfish were tagged with acoustic transmitters and monitored in the Fitzroy River estuary and adjacent King Sound (Kimberley, Western Australia) between August 2015 and November 2017. Dwarf sawfish observed within the Fitzroy River estuary and King Sound were juveniles, ranging between 740 and 2,540 mm in total length. Catch per unit effort of dwarf sawfish in the late dry season was relatively high in the estuary, with the catch rate in 2015 being one of the highest reported for any sawfish species. Acoustic detections revealed a distinct seasonal pattern in the use of different parts of the estuary and King Sound, which was found to be driven by salinity. Dwarf sawfish predominately occupied a single large pool near the terminus of the tidal limit in the late dry season (August–November), before transitioning to regions in closer proximity to the river mouth or in King Sound in the wet and early dry seasons (December–July). Given the high abundance and residency of dwarf sawfish in the Fitzroy River estuary, this area is an important nursery for the species during the late dry season and should be formally recognized as a habitat protection area for the species.
Publisher: Oxford University Press (OUP)
Date: 29-11-2017
Publisher: Wiley
Date: 29-10-2007
Publisher: Brill
Date: 2004
Publisher: Magnolia Press
Date: 12-04-2013
DOI: 10.11646/ZOOTAXA.3637.4.1
Abstract: A new species of pygmy perch (Percichthyidae) from south-western Australia is described on the basis of 15 specimens collected from the Hay River system. Nannoperca pygmaea sp. nov. differs from the sympatric congener N. vittata (Castelnau) by the absence of dark pigment on the ventral surface anterior to the anus, the possession of thin latero-ventral stripes, generally fewer dorsal rays and fewer anal rays, hind margin of scales on caudal peduncle without distinct pigment, and a more pronounced spot (ocellus) that is surrounded by a halo at the termination of the caudal peduncle. The new species is distinguished from congeners Nannoperca australis Günther, N. oxleyana Whitley and N. variegata Kuiter and Allen in possessing an exposed and serrated preorbital bone and jaws that may just reach to below the anterior margin of the eye, versus a smooth and hidden preorbital and the jaws reaching to at least below the pupil and from the remaining congener, N. obscura (Klunzinger) in possessing a distinct haloed ocellus at base of caudal fin versus an indistinct barring, as well as a dark spot behind operculum, and the lack of dusky scale margins. It differs from the other sympatric pygmy perch found in the region, N. balstoni Regan, by the presence of an exposed rear edge of the preorbital (vs. hidden under skin), fewer transverse scale rows (13 vs. 15-16), small mouth (rarely reaching eye vs. reaching well beyond eye), ctenoid (vs. cycloid) body scales, generally fewer pectoral rays and smaller maximum size. Allozyme analyses unequivocally demonstrate that sympatric populations of N. pygmaea sp. nov. and N. vittata belong in different genetic lineages, display no genetic intermediates, and are diagnosable by fixed allozyme differences at 15 different loci. Due to its extremely restricted range, where it is known from only 0.06 km2, N. pygmaea sp. nov. requires urgent legislative protection.
Publisher: Wiley
Date: 19-09-2021
DOI: 10.1111/JFB.14895
Abstract: Gambusia holbrooki is one of the world's most environmentally damaging introduced species, being notoriously difficult to control once established. A composite double‐winged fyke net comprising four vertically stacked compartments was developed to determine the potential to control G. holbrooki , while reducing negative interactions of this aggressive species with small threatened fishes. The stacked fyke net captured three times as many G. holbrooki as a conventional fyke net while maintaining consistent catches of native fishes relative to that from a conventional fyke net, and detected species‐specific vertical distributions. This stratified net design represents a valuable management option for controlling this agonistic species or for limiting antagonistic interactions between G. holbrooki and native species during typical fyke s ling of native ecosystems.
Publisher: Cold Spring Harbor Laboratory
Date: 12-03-2023
DOI: 10.1101/2023.03.08.531828
Abstract: Anthropogenic climate change is forecast to drive regional climate disruption and instability across the globe. This issue is likely to be exacerbated within bio ersity hotspots, both due to the greater potential for species loss but also to the possibility that endemic lineages might not have experienced significant climatic variation in the past, limiting their evolutionary potential to respond to rapid climate change. We assessed the role of climatic stability on the accumulation and persistence of lineages in an obligate freshwater fish group endemic to a bio ersity hotspot. Southwest Western Australia (SWWA). Western pygmy perch ( Nannoperca vittata ) and little pygmy perch ( Nannoperca pygmaea ). We s led 33 in iduals from nine populations spanning the range of both study taxa to explore their phylogeographic history. Using a combination of genomic (ddRAD-seq) and environmental approaches, we investigated population ergence and phylogenetic relationships, delimited species and estimated changes in species distributions since the Pliocene. We identified two deep phylogroups comprising three ergent clusters, which showed no historical connectivity since the Pliocene. We conservatively suggest these represent three isolated species with additional intraspecific structure within one widespread species. All lineages showed long-term patterns of isolation and persistence owing to climatic stability. Our results highlighted the role of climatic stability in allowing the persistence of isolated lineages in the SWWA. This bio ersity hotspot is under compounding threat from ongoing climate change and habitat modification, which may further threaten previously undetected cryptic ersity across the region.
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/MF10100
Abstract: Secondary salinisation represents an important threat to terrestrial and aquatic habitats throughout the world. In south-western Australia, widespread salinisation of waterways has caused large range reductions in the highly endemic freshwater fish fauna. We hypothesised that differences in the distributions of three fish species within the salinised Blackwood River would be related to their salinity tolerances. Galaxias occidentalis was widespread throughout the catchment, whereas Nannoperca vittata was restricted to the main channel and freshwater tributaries of the lower catchment, and Nannatherina balstoni was restricted to those tributaries and a perennial section of the main channel that received a considerable amount of fresh groundwater. Acute salinity tolerances (Effect Concentrations) of G. occidentalis and N. vittata were similar (EC50 ∼14.6 g L–1), but significantly greater than that of N. balstoni (EC50 ∼8.2 g L–1). The greater geographical range of G. occidentalis, compared with N. vittata, may be a consequence of the dispersal capability of the former species, and the lower salinity tolerance of N. balstoni contributes to its highly restricted range. The findings demonstrate that secondary salinisation has greatly impacted these freshwater fishes, and fresh groundwater refuges, predicted to decrease due to reduced rainfall, appear crucial in maintaining remnant populations.
Publisher: Elsevier BV
Date: 05-2017
Publisher: Wiley
Date: 12-04-2014
DOI: 10.1111/GCB.12444
Abstract: There is little understanding of how climate change will impact potamodromous freshwater fishes. Since the mid 1970s, a decline in annual rainfall in south-western Australia (a globally recognized bio ersity hotspot) has resulted in the rivers of the region undergoing severe reductions in surface flows (ca. 50%). There is universal agreement amongst Global Climate Models that rainfall will continue to decline in this region. Limited data are available on the movement patterns of the endemic freshwater fishes of south-western Australia or on the relationship between their life histories and hydrology. We used this region as a model to determine how dramatic hydrological change may impact potamodromous freshwater fishes. Migration patterns of fishes in the largest river in south-western Australia were quantified over a 4 year period and were related to a number of key environmental variables including discharge, temperature, pH, conductivity and dissolved oxygen. Most of the endemic freshwater fishes were potamodromous, displaying lateral seasonal spawning migrations from the main channel into tributaries, and there were significant temporal differences in movement patterns between species. Using a model averaging approach, amount of discharge was clearly the best predictor of upstream and downstream movement for most species. Given past and projected reductions in surface flow and groundwater, the findings have major implications for future recruitment rates and population viabilities of potamodromous fishes. Freshwater ecosystems in drying climatic regions can only be managed effectively if such hydro-ecological relationships are considered. Proactive management and addressing existing anthropogenic stressors on aquatic ecosystems associated with the development of surface and groundwater resources and land use is required to increase the resistance and resilience of potamodromous fishes to ongoing flow reductions.
Publisher: Wiley
Date: 26-06-2023
DOI: 10.1002/AQC.3982
Abstract: Roads affect the connectivity of habitat and inhibit movements of animals as a result of road avoidance and road‐related mortalities. Freshwater turtles are particularly vulnerable to mortality on roads, as females must often cross them when they leave the aquatic environment to nest. Ecopassages designed to enable safe movement across roads by wild animals may be an effective measure to reduce adverse impacts. Limited information exists, however, on effective design criteria for freshwater turtles. A willingness‐to‐utilize study was used to assess factors that may influence the use of a tunnel underpass by the southwestern snake‐necked turtle ( Chelodina oblonga ), a species whose populations are declining, in part, through road‐related mortalities of nesting females. Female C. oblonga were sourced from an urban wetland and placed in an enclosure with exits of varying tunnel lengths (12 and 25 m) and lighting treatments (‘light’ and ‘dark’) to assess the conditions that would promote successful passage. Generalized linear modelling showed that light treatments had a significantly increased likelihood of successful and faster passage for both 12 and 25 m tunnels than the dark treatments. Tunnel length had no effect either on success or rate of passage. This study provides the first account of the factors that may optimize successful tunnel passage by C. oblonga to reduce road‐related mortality, contributing to the conservation and management of the species and freshwater turtles more generally.
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/MF10308
Abstract: Freshwater environments and their fishes are particularly vulnerable to climate change because the persistence and quality of aquatic habitat depend heavily on climatic and hydrologic regimes. In Australia, projections indicate that the rate and magnitude of climate change will vary across the continent. We review the likely effects of these changes on Australian freshwater fishes across geographic regions encompassing a ersity of habitats and climatic variability. Commonalities in the predicted implications of climate change on fish included habitat loss and fragmentation, surpassing of physiological tolerances and spread of alien species. Existing anthropogenic stressors in more developed regions are likely to compound these impacts because of the already reduced resilience of fish assemblages. Many Australian freshwater fish species are adapted to variable or unpredictable flow conditions and, in some cases, this evolutionary history may confer resistance or resilience to the impacts of climate change. However, the rate and magnitude of projected change will outpace the adaptive capacities of many species. Climate change therefore seriously threatens the persistence of many of Australia’s freshwater fish species, especially of those with limited ranges or specific habitat requirements, or of those that are already occurring close to physiological tolerance limits. Human responses to climate change should be proactive and focus on maintaining population resilience through the protection of habitat, mitigation of current anthropogenic stressors, adequate planning and provisioning of environmental flows and the consideration of more interventionist options such as managed translocations.
Publisher: Wiley
Date: 19-05-2020
DOI: 10.1002/AQC.3346
Abstract: Small‐bodied freshwater fishes are commonly overlooked in threatened species management despite being highly imperilled. Before this study, the newly described little pygmy perch ( Nannoperca pygmaea ) was known from only 0.06 km 2 of habitat in a single catchment in south‐western Australia and a lack of knowledge prevented an understanding of its conservation status and priority actions. The present study determined the distribution, biology, and movement patterns of N. pygmaea and compared these with other small, sympatric percihthyids to assess its conservation status and likely resilience to threatening processes. The current ‘extent of occurrence' of N. pygmaea was determined to be 3,420 km 2 and the ‘area of occupancy' was 10 km 2 . Nannoperca pygmaea inhabited permanent refuge pools in the main stem of an ephemeral, secondarily salinized catchment where salinities remained ppt during summer. During winter N. pygmaea undertook a short upstream migration into a seasonally flowing freshwater tributary to serially spawn. The timing of reproduction was partitioned among three sympatric pygmy perches within the austral winter/spring period. The species qualifies as ‘Endangered' under the IUCN Red List assessment criteria. Its restriction to freshwater refugia within salinized rivers suggests that N. pygmaea may have a limited salinity tolerance similar to the sympatric, threatened Nannatherina balstoni , and that the species is susceptible to prolonged drought, drying of critical baseflow refuges, increasing salinization, and introductions of alien species. The study serves as an ex le that small‐bodied freshwater fishes need greater research attention to understand the biological and environmental mechanisms underpinning their decline.
Publisher: Wiley
Date: 30-11-2021
DOI: 10.1111/FWB.13843
Abstract: Gambusia holbrooki is arguably the most widely introduced and ecologically damaging freshwater fish in the world. Although aspects of its aggressive behaviour have been studied in lentic environments and ex situ experiments, the physical damage to native freshwater fishes in riverine systems caused by this behaviour remains relatively unknown. This study quantified the spatial and temporal patterns of abundance of G. holbrooki and the prevalence of fin‐nipping damage on freshwater fishes in river systems of south‐western Australia, a globally endemic hotspot with a high proportion of threatened species. It then determined the environmental factors influencing the abundance of G. holbrooki and the prevalence of fin‐nipping damage on native fishes. Caudal fin damage differed significantly among four endemic native fishes, with damage being most prevalent in the percichthyid Nannoperca vittata , which has a similar size and ecological niche to G. holbrooki . Fin‐nipping damage of native species also showed significant seasonal variation occurring most commonly during summer and autumn when many rivers in this region cease to flow and contract to refuge pools, probably increasing interactions between G. holbrooki and the native fishes. Moreover, the environmental variables that best explained both the density of G. holbrooki and the prevalence of fin‐nipping were broadly similar and were characteristic of more degraded habitats. We anticipate that habitat degradation, river regulation and severe declines in surface flows resulting from climate change will benefit G. holbrooki to the detriment of native fishes. Restoration of riverine environments along with public education c aigns to prevent the further spread of G. holbrooki or the introduction of additional species is crucial to mitigate their effects on aquatic ecosystems.
Publisher: Informa UK Limited
Date: 06-2007
Publisher: Wiley
Date: 18-11-2016
DOI: 10.1111/JFB.13214
Abstract: Following the complete eradication of the alien piscivorous perch Perca fluviatilis from a potable reservoir, the abundance of the endemic western minnow Galaxias occidentalis, which was previously undetectable prior to the initial eradication event, increased dramatically. The study reveals the potential of reservoirs to act as ecological refuges and has implications for understanding the relative effects of alien fishes v. habitat alteration on native freshwater fishes.
Publisher: CSIRO Publishing
Date: 2002
DOI: 10.1071/MF02047
Abstract: Within Western Australia, Perca fluviatilis is restricted to the south-western corner and is found in the Swan, Murray, Harvey, Collie, Capel, Carbunup, Margaret, Blackwood, Donnelly and Warren river systems. Age data suggest it was released into Big Brook Dam (Warren River) in 1992 or 1993, where it has since played a role in eliminating the native teleosts. Its success here is attributed to a young age at maturity, rapid growth (compared with populations elsewhere), predatory nature, large size (compared with native fish), broad environmental and habitat tolerances, and absence of predators. Gonadal development initiates in late summer, with peak spawning between August and September. Males and females attained maturity in their first and second years, respectively, which is earlier than reported for most Northern Hemisphere populations and can be attributed to their rapid growth here because of the warmer climate. At ages 1, 2, 3, 4 and 5, males, on average, attained 102, 159, 206, 246 and 280 mm total length (TL) and females had attained 104, 166, 228, 290 and 351 mm TL at the respective ages. Diets of fish 50–200 mm TL comprised mainly small aquatic invertebrates, whereas larger fish preyed almost exclusively on decapods, mainly marron (Cherax tenuimanus), and teleosts.
Publisher: Wiley
Date: 08-08-2019
DOI: 10.1002/AQC.3193
Publisher: Wiley
Date: 05-02-2020
DOI: 10.1111/FWB.13479
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/MF05221
Abstract: This study tested the hypothesis that the introduced yabbie Cherax destructor Clark, 1936 has the potential to compete with the endemic marron Cherax cainii Austin, 2002 for food resources. Multiple stable isotope analyses were conducted in the Hutt River, Western Australia, in summer (December) and winter (July), 2003. Summer s les indicated that these species occupied similar predatory trophic positions when their assimilated diet consisted of a large proportion of Gambusia holbrooki. Although C. cainii continued to assimilate mostly animal matter based on winter signatures, those of C. destructor appeared to shift towards a more herbivorous trophic position. The study suggests that C. destructor and C. cainii may be keystone species in the Hutt River, possibly altering the cycling of nutrients and structure of the aquatic food web since their introduction into this system. The ecological implications of the continued invasion of C. destructor into the aquatic systems of south-western Australia, particularly with regard to competition with the other endemic freshwater crayfishes, are discussed.
Publisher: CSIRO Publishing
Date: 2003
DOI: 10.1071/MF02077
Abstract: The reproductive biology of Cherax cainii was studied in an impoundment dam in south-western Australia using histological examination of ovarian development (previous studies describing the reproductive biology of freshwater crayfish have relied solely on macroscopic descriptions of gonadal development). Spawning occurred between August and November and peaked in late August and September, with the percentage of berried females increasing from 50% in September to 96% in November before declining to 11% in December. Juveniles were released from berried females between late November and early December. Female gonads recovered dramatically after spawning with 81% of mature females possessing stage IV (maturing) gonads in March. The respective orbital carapace lengths at which 50 and 95% of C. cainii reached maturity were 32.1 and 37.9 mm for females, and 28.6 and 38.8 mm for males. The mean potential fecundity (i.e. number of mature ovarian oocytes prior to spawning) was 443 compared with 286 for the mean effective fecundity (i.e. number of pleopodal eggs, embryos or juveniles following spawning). The fact that the full ovarian reproductive potential of C. cainii is not attained is probably due to the limitation of egg attachment space on the pleopods.
Publisher: Springer Science and Business Media LLC
Date: 20-05-2020
Publisher: Informa UK Limited
Date: 08-2004
Publisher: Cambridge University Press (CUP)
Date: 2021
DOI: 10.1017/S0022149X21000365
Abstract: The Asian fish tapeworm ( Schyzocotyle acheilognathi ) is an important fish parasite with a wide host range that infects over 300 species of fish worldwide. Schyzocotyle acheilognathi has been reported from eastern coastal areas of Australia, but has not been previously reported in Western Australia (WA). During a control program for invasive freshwater fishes in south-western WA, a region with a unique and highly endangered freshwater fish fauna, tapeworms identified as S . acheilognathi from their distinctive scolex morphology were found at a prevalence of 3.3% in goldfish ( Carassius auratus ), 37.0% in koi carp ( Cyprinus carpio haematopterus ) and 65.0% in eastern gambusia ( Gambusia holbrooki ) in a small suburban lake to the north of Perth. For molecular confirmation, the 18S ribosomal RNA gene was targeted at hypervariable V4 region. Koi carp isolates were 100% identical to S . acheilognathi isolated from varying hosts, including the red shiner ( Cyprinella lutrensis ) and a human s le. Sequences obtained from two eastern gambusia were identified as S . acheilognathi , but formed a discrete cluster and may represent a novel genotype. Isolates from two other eastern gambusia and two goldfish formed a distinct clade with only 91.9% similarity to previously sequenced isolates of S . acheilognathi . This emphasizes the importance of molecular identification methods in addition to morphological identification. The presence and potential for transmission of these parasites in south-western WA may threaten the health of native fishes, which are immunologically naïve to this introduced parasite. Immediate control or containment measures should be implemented to halt the spread of these parasites.
Publisher: The Royal Society
Date: 04-2019
Abstract: Traditional forms of marine wildlife research are often restricted to coarse telemetry or surface-based observations, limiting information on fine-scale behaviours such as predator–prey events and interactions with habitat features. We use contemporary animal-attached cameras with motion sensing dataloggers, to reveal novel behaviours by white sharks, Carcharodon carcharias , within areas of kelp forest in South Africa. All white sharks tagged in this study spent time adjacent to kelp forests, with several moving throughout densely kelp-covered areas, navigating through channels and pushing directly through stipes and fronds. We found that activity and turning rates significantly increased within kelp forest. Over 28 h of video data revealed that white shark encounters with Cape fur seals, Arctocephalus pusillus pusillus , occurred exclusively within kelp forests, with seals displaying predator evasion behaviour during those encounters. Uniquely, we reveal the use of kelp forest habitat by white sharks, previously assumed inaccessible to these large predators.
Publisher: Regional Euro-Asian Biological Invasions Centre Oy (REABIC)
Date: 02-2013
Publisher: Wiley
Date: 10-10-2017
DOI: 10.1111/JFB.13461
Abstract: Whale sharks Rhincodon typus were monitored via acoustic transmitters at the northern end of Western Australia's Ningaloo Marine Park to establish the extent to which the species inhabits the region beyond the whale-shark ecotourism industry season, which usually extends from March to August in each year. Despite the vast majority (c. 98%) of photographic submissions of R. typus from Ningaloo Reef being between March and August, acoustic detections from the tagged R. typus at Ningaloo were recorded in all months of the year, but do not preclude the occurrence of extended absences. It is concluded that as a species, R. typus occurs year round at Ningaloo, where it generally remains in close proximity to the reef edge, but that some in iduals move outside of the detection range of the array for extended periods.
Publisher: University of Chicago Press
Date: 12-2014
DOI: 10.1086/677815
Publisher: Oxford University Press (OUP)
Date: 2005
DOI: 10.1651/C-2518
Publisher: CSIRO Publishing
Date: 2015
DOI: 10.1071/ZO15002
Abstract: Westralunio carteri is the only species of freshwater mussel found in south-western Australia and, owing to a lack of comprehensive information on its ecology, its conservation status has been speculative. To more accurately predict the true conservation status of this species, the historical and contemporary distributional records were modelled with environmental data that identified salinity, perenniality and total nitrogen as variables responsible for limiting the species’ current extent of occurrence, inferring threatening processes. The species was found to have undergone a 49% reduction in extent of occurrence in less than three generations, due primarily to secondary salinisation. Current distribution is bounded by Gingin Brook in the north to the Kent, Goodga and Waychinicup Rivers in the South, within 50–100 km of coastal south-western Australia. Field observations indicated that W. carteri was almost never found at sites where mean salinity was .6 g L–1. This was corroborated by laboratory tolerance trials that showed that W. carteri has an acute salinity tolerance (LD50) of 1.6–3.0 g L–1. Application of IUCN Red List criteria indicates that W. carteri qualifies for listing as vulnerable. Conservation management measures should focus on maintaining existing populations.
Publisher: Elsevier BV
Date: 03-2016
Publisher: Springer Science and Business Media LLC
Date: 10-2005
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/PC15043
Abstract: The spotted galaxias (or trout minnow), Galaxias truttaceus, is a species that is restricted to south-western and south-eastern Australia, but there has long been conjecture as to whether the geographically and Critically Endangered Western Australian populations represent a subspecies (Galaxias truttaceus hesperius). We provide evidence that Western Australian populations, on the basis of a combination of genetic, geographic and ecological criteria, should be considered an evolutionary significant unit, which merits management as a high conservation priority. Substructure at nuclear and matrilineal genetic markers is not suggestive of species-level ergence, but rather of discrete western and eastern Australian subpopulations with limited contemporary gene flow. In contrast to many eastern populations that are diadromous, all western populations are potamodromous. Adults live and spawn in riverine habitats and larvae drift downstream to coastal lakes, where they spend several months, before undertaking a distinct upstream recruitment migration as juveniles to colonise riverine habitats. Instream barriers that disconnect riverine and lentic habitats restrict distributional range and presumably affect reproductive success of Western Australian populations. Conserving the remaining populations in Western Australia will require ongoing efforts to reduce the impact of emerging threats, particularly those related to instream barriers, introduced species and reductions in water quantity and quality.
Publisher: Informa UK Limited
Date: 05-2013
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/PC19012
Abstract: Understanding the modalities of aquatic species introductions is important in predicting and preventing new invasions. Australia’s Pilbara Province is an arid region with no naturally occurring freshwater crayfishes. We assessed the population demographics and reproductive potential of redclaw crayfish (Cherax quadricarinatus) in Lake Poongkaliyarra, a major Pilbara water supply reservoir, in which public access and fishing are prohibited. We found the population to have a high relative abundance with a range of size-cohorts present. The species was believed to have first been introduced into the reservoir from at least 2010 and has subsequently been introduced and established in other lotic systems in the region, probably through deliberate releases from the lake for the purposes of providing fishing opportunities to areas where public access is permitted. Introductions of C. quadricarinatus in other parts of Australia and the world have also initially established in reservoirs before subsequently colonising natural systems. The study highlights the potential for reservoirs to act as primary stepping stones for invasion by freshwater crayfish.
Publisher: Wiley
Date: 28-09-2020
DOI: 10.1002/ECO.2253
Publisher: Inter-Research Science Center
Date: 26-09-2017
DOI: 10.3354/ESR00847
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/PC19053
Abstract: Globally, freshwater fishes are declining at an alarming rate. Despite much evidence of catastrophic declines, few Australian species are listed as threatened under national legislation. We aim to help redress this by identifying the Australian freshwater fishes that are in the most immediate risk of extinction. For 22 freshwater fishes (identified as highly threatened by experts), we used structured expert elicitation to estimate the probability of extinction in the next ~20 years, and to identify key threats and priority management needs. All but one of the 22 species are small (& mm total length), 12 have been formally described only in the last decade, with seven awaiting description. Over 90% of these species were assessed to have a & % probability of extinction in the next ~20 years. Collectively, the biggest factor contributing to the likelihood of extinction of the freshwater fishes considered is that they occur in small (distributions ≤44km2), geographically isolated populations, and are threatened by a mix of processes (particularly alien fishes and climate change). Nineteen of these species are unlisted on national legislation, so legislative drivers for recovery actions are largely absent. Research has provided strong direction on how to manage ~35% of known threats to the species considered, and, of these, ~36% of threats have some management underway (although virtually none are at the stage where intervention is no longer required). Increased resourcing, management intervention and social attitudinal change is urgently needed to avert the impending extinction of Australia’s most imperilled freshwater fishes.
Publisher: Elsevier BV
Date: 07-2011
Publisher: Springer Science and Business Media LLC
Date: 08-07-2006
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/MF08169
Abstract: The freshwater sawfish (Pristis microdon) is a critically endangered elasmobranch. Ontogenetic changes in the habitat use of juvenile P. microdon were studied using acoustic tracking in the Fitzroy River, Western Australia. Habitat partitioning was significant between 0+ (2007 year class) and larger 1+ (2006 year class) P. microdon. Smaller 0+ fish generally occupied shallower water ( .6 m) compared with 1+ in iduals, which mainly occurred in depths .6 m. Significant differences in hourly depth use were also revealed. The depth that 1+ P. microdon occupied was significantly influenced by lunar phase with these animals utilising a shallower and narrower depth range during the full moon compared with the new moon. This was not observed in 0+ in iduals. Habitat partitioning was likely to be related to predator avoidance, foraging behaviours, and temperature and/or light regimes. The occurrence of 1+ P. microdon in deeper water may also result from a need for greater depths in which to manoeuvre. The present study demonstrates the utility of acoustic telemetry in monitoring P. microdon in a riverine environment. These results demonstrate the need to consider the habitat requirements of different P. microdon cohorts in the strategic planning of natural resources and will aid in the development of management strategies for this species.
Publisher: Regional Euro-Asian Biological Invasions Centre Oy (REABIC)
Date: 03-2013
Publisher: Cold Spring Harbor Laboratory
Date: 11-06-2023
DOI: 10.1101/2023.06.08.544203
Abstract: Home range size and metabolic rate of animals are expected to scale with body mass at similar rates with home ranges expanding to meet increased metabolic requirements. This expectation has widely been tested using lab-derived estimates of basal metabolic rate as proxies for field energy requirements, however, it is unclear if existing theory aligns with patterns of home range scaling observed in the field. Here, we conduct the first direct field test of the relationship between home range and metabolic rate allometry. Using acoustic telemetry, we simultaneously measured the in idual home range size and field metabolic rate of lemon sharks (Negaprion brevirostris) spanning one order of magnitude in body mass. Although scaling rates of field metabolic rate were consistent with standard metabolic rate, home range size scaled at shallower rates than metabolic rates. This is evidence for strong top-down controls on home range scaling rates, likely a result of predation pressure placing constraints on home range expansions. Consequently, direct resource competition can lead to decreased home range scaling rates. We highlight inconsistencies with theory on the effects of population density and competition on home range scaling and propose that the influence of erse types of competition should be examined.
Publisher: Wiley
Date: 15-11-2006
Publisher: Wiley
Date: 21-03-2020
DOI: 10.1002/AQC.3324
Publisher: Elsevier BV
Date: 05-2016
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/ZO12022
Abstract: Glochidia (parasitic larvae) of freshwater mussels generally require a fish as a host. Westralunio carteri Iredale, 1934 (Bivalvia : Hyriidae), the only freshwater mussel found in south-western Australia, was listed as Vulnerable, but recently changed to Least Concern (International Union for the Conservation of Nature). Glochidia were found on four alien and seven native species of fish from 18 sites in the South West Coast Drainage Division. On alien fishes, prevalence of glochidia ranged from 0.0 to 41.0% and mean intensity (number of glochidia per infested fish) from 1.0 to 6.0, while on native fishes prevalence was 9.2–90.5% and intensity was 2.3–7.1. Glochidia infestation was greatest on benthic fishes, which may be a consequence of greater encounter rates, but other factors, such as host size, probably also influence glochidia prevalence and intensity. Glochidia were generally restricted to fins of infested fish, and were rarely on gills or the body surface. In the laboratory, four native and one alien fish species were found to be competent hosts for their ability to produce juvenile W. carteri, but two alien fish species were not. The inability of some alien fishes to produce juvenile W. carteri could potentially reduce recruitment success in areas dominated by alien fishes.
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/ZO14004
Abstract: Upstream migration of juvenile stages of temperate Australian hidromous fish typically coincides with seasonally low river discharge when hydraulic (e.g. cascades) and physical (e.g. rock bars) barriers may be common. The ability to ‘climb’ or ‘jump’ may be expected to assist in negotiating low-flow barriers however, it is presumed to be limited to a few native Australian freshwater fishes. Juvenile stages of Galaxias truttaceus Valenciennes, 1846 were observed ‘climbing’ and ‘jumping’ to successfully negotiate a low, vertical weir wall during their upstream recruitment migrations in south-western Australia. Based on this observation, we propose initial definitions for ‘climbing’ and ‘jumping’ to describe locomotory strategies employed by fishes to negotiate obstacles that would otherwise prevent free passage by normal swimming behaviour. Greater knowledge of the climbing, jumping and swimming performance, especially for small-bodied species and early life stages, will help improve the management of instream barriers for this critically endangered species and other freshwater fishes of southern Australia.
Publisher: Wiley
Date: 11-11-2010
Publisher: Wiley
Date: 10-04-2017
DOI: 10.1002/ECY.1737
Publisher: Springer Science and Business Media LLC
Date: 09-2017
Publisher: Wiley
Date: 05-2015
DOI: 10.1111/JFB.12668
Abstract: A pilot study targeting sawfishes in the southern Pilbara region of Western Australia, which is undergoing a major expansion in human activity, was conducted using gillnets during April and October 2011 in the Ashburton Estuary and adjacent mangrove creeks. Catch per unit effort was greatest in the Ashburton Estuary in October, due to an influx of green sawfish Pristis zijsron pups, and was orders of magnitude higher than previously reported for any Pristidae the study sites contained P. zijsron up to almost 3 m total length. This study identified the first pupping site for P. zijsron in Western Australia, and the most southerly known nursery area for the species in Australian waters, and is potentially the most important globally.
Publisher: Wiley
Date: 27-04-2016
DOI: 10.1111/FAF.12161
Publisher: Elsevier BV
Date: 10-2018
Publisher: Wiley
Date: 12-08-2017
DOI: 10.1111/EFF.12288
Publisher: Wiley
Date: 04-2019
DOI: 10.1002/FEE.2028
No related grants have been discovered for Stephen Beatty.