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Cowes, Australia

Kirkwood R.,Phillip Island Nature Parks | Arnould J.P.Y.,Deakin University
Australian Journal of Zoology | Year: 2011

Australian fur seals (Arctocephalus pusillus doriferus) are the most conspicuous and abundant marine mammal in shelf waters of south-eastern Australia. To successfully rear offspring, the females must encounter sufficient prey on each foraging trip out of a central place for periods up to11 months each year. We investigated foraging trip strategies and habitat use by the females in three winterspring periods, 200103, from four colonies that span the species' latitudinal range and contribute 80% of pup production. Trip durations of 37 females averaged 6.1±0.5 (s.e.) days, although >90% of the seal's time at sea was spent <150km travel (<2 days) away. Most females exhibited strong fidelities to individually preferred hot-spots. Females from colonies adjacent to productive shelf-edge waters generally had shorter trips, had smaller ranges, foraged closer to colonies and exhibited less diversity in trip strategies than did those from colonies more distant from a shelf-edge. From a management perspective, there was minimal overlap (<1%) between where females foraged and a system of marine reserves established in 2007, suggesting that habitats visited by lactating Australian fur seals currently receive minimal legislative protection. © 2011 CSIRO. Source

Sutherland D.R.,Phillip Island Nature Parks | Glen A.S.,Landcare Research | De Tores P.J.,Invasive Animals Co operative Research Center
Proceedings of the Royal Society B: Biological Sciences | Year: 2011

Emerging evidence increasingly illustrates the importance of a holistic, rather than taxon-specific, approach to the study of ecological communities. Considerable resources are expended to manage both introduced and native mammalian carnivores to improve conservation outcomes; however, management can result in unforeseen and sometimes catastrophic outcomes. Varanid lizards are likely to be apex- or mesopredators, but being reptiles are rarely considered by managers and researchers when investigating the impacts of mammalian carnivore management. Instances of mesopredator release have been described for Varanus gouldii as a result of fox and cat management in Australia, with cascading effects on faunal community structure. A meta-analysis showing extensive dietary niche overlap between varanids, foxes and cats plus a review of experimental and circumstantial evidence suggests mesopredator release of V. gouldii and about five other medium to large species of varanid lizard is likely in other regions. This highlights the need for managers to adopt a whole-of-community approach when attempting to manage predators for sustained fauna conservation, and that additional research is required to elucidate whether mesopredator release of varanids is a widespread consequence of carnivore management, altering the intended faunal responses. © 2010 The Royal Society. Source

Eastern Curlews breed in Siberia in the boreal spring and summer and migrate to Australia in the austral spring and summer. The Eastern Curlew is notable for its very long, decurved bill; this sexually dimorphic characteristic represents approximately 25-30% of total body length. Female curlews have the longest bill of any wader. Diet and prey choice in relation to availability and profitability were examined over two non-breeding periods in Western Port in southern Australia. Diet was determined from direct feeding observations, examination of pellets collected at high-tide roosts (during daytime and night-time) and by following tracks of foraging curlews. Male and female curlews used the intertidal feeding areas differently: females used more sandy areas and males more muddy areas. This difference may be related to sexual dimorphism in bill length and could reflect substantial dietary differences. Tasselled Crab Pilumnus fissifrons was the most common prey, followed by Australian Ghost Shrimp Trypaea australiensis, Two-spined Crab Litocheira bispinosa and Sentinel Crab Tasmanoplax latifrons. The availability of prey was examined in aquaria through examination of burrowing behaviour and other activity patterns in relation to tidal movements and levels of daylight. Prey behaviour explained the greater consumption of male Ghost Shrimps and the differences in diet between day and night. More Ghost Shrimps and Sentinel Crabs and fewer Two-spined Crabs were taken during the day than during night. Prey choice was examined by measuring the calorific values of prey and potential prey species. Generally, curlews took the more energy valuable prey, but prey behaviour and prey availability mostly determined prey choice, not the energetic value of prey. Source

Lancaster M.L.,University of Adelaide | Arnould J.P.Y.,Deakin University | Kirkwood R.,Phillip Island Nature Parks
Animal Conservation | Year: 2010

Genetic variation, and the way in which it is partitioned among populations, has implications for a species' survival and evolutionary potential. Such information is particularly important for the successful conservation and management of species that have experienced past human impacts and potential losses of genetic diversity. Overharvesting of the Australian fur seal Arctocephalus pusillus doriferus in the 18th and 19th centuries resulted in severe population reductions and elimination of an estimated 17 of 26 colonies. Currently, the subspecies is recovering and c. 20 000 pups are produced annually at 13 colony sites, most of which are situated in Bass Strait in south-eastern Australia. Genetic analysis of samples collected from pups captured at nine colonies revealed no difference in allelic diversity or heterozygosity at five microsatellite loci and no differences in haplotype diversity within a 344 bp region of the mitochondrial DNA control region. There was some evidence for isolation by distance but the program structure predicted a single cluster of individuals. Gene flow among colonies appears to be substantial at present, indicating that the Australian fur seal is currently a single, panmictic unit. © 2009 The Authors. Journal compilation © 2009 The Zoological Society of London. Source

Dann P.,Phillip Island Nature Parks | Chambers L.,Center for Australian Weather and Climate Research
Climate Research | Year: 2013

Using a 40 yr demographic database of little penguins Eudyptula minor, we investigated anticipated impacts of climatic changes on the penguin population at Phillip Island, southeastern Australia, and the potential economic impact on the associated tourism industry over the next century. We project a small loss of penguin breeding habitat due to sea level rise, although breeding habitat is unlikely to be limiting over this period. However, some erosion in the vicinity of tourism infrastructure will undoubtedly occur which will have economic implications. We anti cipate little direct impact of decreased rainfall and humidity. However, fire risk may increase, and extreme climate events may reduce adult and chick survival slightly. Warmer oceans are likely to improve recruitment into the breeding population but the effect on adult survival is unclear. Overall, many aspects of little penguin biology are likely to be affected by climatic change but no net negative effect on population size is projected from existing analyses. Ocean acidification has the potential to be a highly significant negative influence, but present assessments are speculative. Some of the predicted negative impacts can be addressed in the shortterm, particularly those resulting from expected changes to the terrestrial environment. Others, particularly in the marine environment, appear to have limited options for mitigation locally. In the absence of evidence indicating population decline, economic impact may be confined to issues for tourism infrastructure due to increased sea-levels during storm events. © Inter-Research 2013. Source

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