AWMS 2018 will be held in Tasmania in December. This conference provides us the opportunity to engage with some of the challenges that have been faced by wildlife managers on the island. Tasmania is presently a refuge for many taxa that were previously present on mainland Australia, and in numbers that most of us dream about. The island supports an abundance of wildlife in the absence of Australia’s two largest eutherian predators: dingos and foxes. Managing this wildlife in the presence of primary production, forestry, urbanisation and road corridors (to name a few issues) presents many challenges for conservation management. The importance of wildlife disease control has also been kept in the forefront of our minds, with issues such as how we handle Devil Facial Tumour disease setting a global precedent for collaboration between researchers, zoos and management. Our annual conferences allow AWMS members to increase our scope and understanding of the issues faced by wildlife managers across Australasia. It will be good to increase our direct engagement with Tasmanian researchers and managers.
Please make sure that you apply for some of our generous awards, and encourage practitioners and students to do the same. Also, for the first time, the AWMS committee has offered a ‘President’s Award’ (directly plagiarising another well-known Aus society) to directly support early career researchers increasing their research profile. I look forward to sharing the Tasmania experience and trust that we ‘see you’ there.
Connectivity and effective population size of eastern Australian grey nurse sharks
The grey nurse shark, Carcharias taurus, is a large coastal shark that has a disjunct global distribution . Grey nurse sharks inhabit sub-tropical to temperate waters and aggregate in shallow rocky gutters and caves that are close to land . Australia is home to two populations of grey nurse sharks; one on the east coast and one on the west coast. These are genetically and geographically isolated from each other and from the rest of the world .
Unfortunately, the coastal distribution of grey nurse sharks makes them very susceptible to human interactions such as fishing and shark nets, and their numbers are declining around the world . This has led to the global classification of Vulnerable under the International Union for Conservation Nature (IUCN). In Australia, the west coast population is listed as Vulnerable and the east coast population is listed as Critically Endangered under the Environment Protection and Biodiversity Act 1999 (EPBC Act). The eastern Australian population has been quite well studied over the past few decades and their persistence in the future has been of great concern. This is due to their low genetic variation and relatively low population size of around 2000 individuals [2, 4].
For my masters, I used genetic techniques to gain more information on the demographics of the east coast population of grey nurse sharks. In particular, I wanted to verify that the east coast population is indeed a panmictic population, find out whether there is sex-biased dispersal, and estimate the effective population size (Ne). Ne is essentially a measure of the number of breeding individuals in the population based on the genetic variation within the sample. Finally, I wanted to estimate the potential loss of genetic variation in the future, based on the Ne estimate. To do this, I analysed 3500 genetic markers called single nucleotide polymorphisms (SNPs) from tissue samples of 63 grey nurse sharks that were collected opportunistically between 1999 and 2007.
My results provided no evidence for sex-biased dispersal and genetic structure that would have indicated separate populations of grey nurse sharks along the east coast. This demonstrates that the eastern grey nurse sharks are a panmictic population with both sexes dispersing, and supports previous field observations of the sharks moving up and down the coastline in synchrony with their reproductive cycle . The estimated Ne was around 400 and simulations of genetic variation over the next 50 generations showed that maintaining the Ne of 400 will lead to a 4% loss in genetic variation.
While a loss of 4% does not seem high, as the Ne lowers, genetic variation is lost at a faster rate. In eastern Australia, at least 12 grey nurse sharks are killed per year through recreational fishing, while others are killed through commercial fishing and from being entangled in shark nets. If these fatalities continue it is possible that the population will continue to decline, leading to a lower Ne and loss in genetic diversity. Currently grey nurse shark management is cross-jurisdictional, which means that rules and regulations are not consistent across their distribution. This study highlights the importance in managing this critically endangered grey nurse shark population as one unit, so that we can better protect and encourage their survival and genetic diversity in the future.
I would like to thank AWMS, my supervisors Adam Stow and Kerstin Bilgmann for their support and guidance, Macquarie University for funding, and NSW Department of Primary Industries for providing the tissue samples.
1. Ahonen, H., R. Harcourt, and A. Stow, Nuclear and mitochondrial DNA reveals isolation of imperilled grey nurse shark populations (Carcharias taurus). Molecular Ecology, 2009. 18(21): p. 4409-4421.
Release methods for reintroductions: Does post-release support influence the outcome?
Hannah L. Bannister
Reintroductions involve translocating animals back to an area where they have become locally extinct, and are used as a tool to reverse species decline and/or restore ecosystem function. Reintroductions are often unsuccessful, are expensive and can be logistically demanding. Release methods—the way animals are physically released— can influence the outcome of a reintroduction. We aimed to compare three release methods to determine how they influenced the post-release dispersal, body mass, survival, and retention of pouch young of brushtail possums (Trichosurus vulpecula) reintroduced to the semi-arid Ikara-Flinders Ranges National Park in South Australia, where the species became locally extinct ~70 years ago. Importantly, one of the key causes of the species’ decline, foxes (Vulpes vulpes), were successfully controlled within the park.
Forty-eight radio-collared possums were divided into three release treatments—immediate release, delayed release (containment for 10 days with supplementary food and shelter) and nest-box release (supplementary food and shelter, no containment), with 8 males and 8 females in each. Radio-tracking to shelter sites at least weekly and trapping at 10, 20, 30, 60 and 90 days post-release was used to address our research questions over a three month period.
Release treatment had no effect on the dispersal distance (Fig. 1), post-release body mass (Fig. 2) or survival of possums (94-100%), or on the retention of pouch young (100%). Delayed release possums did, however, take significantly longer to settle than immediate release and nest-box release possums. Possums in all treatments lost weight, but relatively quickly regained it. In the first few days after release, possums were often found sheltering in unsafe locations such as the burnt out bases of river redgums (Eucalyptus camaldulensis), leaving them vulnerable to predators should they have been encountered.
Figure 1: Distance from release site over Figure 2: Change in body mass over time,
In our predator-controlled reintroduction environment, immediate releases were most suitable as possums settled quickly and the method is cheapest both logistically and financially. In contrast to popular opinion, delayed release methods are not always beneficial or required. However, should predators have been present in higher numbers, possums sheltering in vulnerable locations may have fallen victim, and delayed releases may have proved more effective during this acclimation period. Despite this, released possums did not utilise supplementary shelter, and supplementary food did not prevent post-release loss of body mass, suggesting alternative methods of presenting post-release support is needed.
Thanks to Pat Hodgens, Tali Moyle, Kiarrah Smith, Cassandra Holt and the Australian Wildlife Conservancy, as well as funding bodies the Department for Environment, Water and Natural Resources, the Foundation for Australia’s Most Endangered Species, Biology Society South Australia, Holsworth Wildlife Research Endowment, Nature Foundation Australia and the University of Adelaide.
Interspecific competition and olfactory communication among New Zealand’s invasive mammalian predators
Dr Patrick Garvey
Stoats (Mustela erminea), feral cats (Felis catus) and ferrets (M. furo) were introduced to New Zealand as agents of biological control and have subsequently decimated populations of many native species. Although the detrimental impacts of these predators are unequivocal, the potential limiting factor of competition among these invasive species is less well understood. The aim of my thesis was to understand the mechanisms that allow invasive predators to coexist, with a focus on two key processes - interspecific competition and olfactory communication.
The initial challenge for my research was to establish whether stoats (focal species) view the larger predators (cats and ferrets) as dominant in interspecific interactions. A pen trial experiment was designed to quantify levels of fear, using a range of behavioural measures (i.e. give up density (GUDs), vigilance, avoidance, and activity patterns). Stoats perceived larger predators as a threat, altering their foraging behaviours and drastically reducing food intake at ‘high risk’ areas. This pen trial revealed a hierarchy in the predator guild and these findings became the cornerstone of my thesis, as they provided a framework to decipher stoat behaviour and distribution patterns.
After quantifying the behavioural responses to physically larger predators, the next step was to investigate the role of olfaction. An experiment was designed to test stoat behavioural responses to apex predator odour in a foraging macrocosm. Contrary to my predictions, stoats displayed a strong drive to investigate the odour of co-evolved dominant predators and there was no evidence of avoidance, although the odour did provoke increased vigilance. Furthermore, ‘prey’ combined with the scent of a dangerous adversary was consumed more rapidly than prey at non-scented controls.
The attraction displayed by captive stoats to dominant predator odour was intriguing and this discovery had potential applications for wildlife management. A field experiment was devised to test wild mesopredator responses to dominant predator odour. This demonstrated that ferret body odour is a powerful attractant for free-ranging stoats, increasing their detection three-fold in comparison to a traditional food lure, while also increasing detections of other mesopredators (hedgehogs and Rattus spp.). Monitoring with rabbit meat alone would have substantially underestimated the distributions and relative abundances of the mesopredator guild.
The last step for my thesis was to examine niche partitioning in a community of invasive predators. I compared reciprocal activity and spatial distribution patterns using an intensive camera trap study that generated 970,000 photographs! Dominant predators (cat/ferret) exhibited ‘resource matching’, selecting for the most abundant mammalian prey, yet also partitioning these resources along the niche axis of habitat and prey species. The subordinate mesopredator exhibited ‘safety matching’, confining its activity to times and locations that reduced the risk of an encounter with dominant predators. Spatiotemporal avoidance by stoats will have associated fitness costs, as this constrains the fundamental niche, reducing access to most abundant prey. Selective removal of larger predators revealed that stoats respond in accordance with the mesopredator release hypothesis, changing from being effectively undetectable to being the most frequently detected predator at the treatment site.
Understanding interactions among introduced carnivores, and the communication mechanisms that maintain predator assemblages, is critical for native species protection in invaded ecosystems. This research provides new insights into invasive predator dynamics and the technique of using predator odour to attractant subordinate species could have applications for conservation efforts worldwide. In summary, the main findings were:
*I wish to thank my supervisors – Roger Pech, Al Glen and Mick Clout – for their constant support and advice throughout this PhD journey.
Abstracts are now being accepted for this years AWMS conference in Hobart 4-6 December. The call for abstracts closes August 31 so download the Call for Abstracts now!
AWMS Awards are now open for application! AWMS has a wide range of awards available for its members.
All applications close 31 August 2018. Head to our website for more information
This year a number of Committee positions will open for nomination. While an official call for nominations will come out in the next newsletter and via email, the AWMS Committee encourages members to consider supporting their Society by nominating for a position. Anyone considering a position on the Committee will require a member to nomimate them and an additional member to second that nomination. Full details will be provided closer to the conference. All positions are two year terms and current holders of the positions can re-nominate. Positions up for nomination are:
Due to the overwhelming response from our members, we can only listed publication titles and contact details for corresponding authors. It's good to see so many papers being produced by AWMS members.
Andrew Veale - Andrew.firstname.lastname@example.org
Veale, A.J., Russell, J.C., King, C.M. (2018) The genomic ancestry, landscape genetics and invasion history of introduced mice in New Zealand. Royal Society Open Science 5 (1), http://rsos.royalsocietypublishing.org/content/5/1/170879
Hannah Bannister - email@example.com
Bannister, H. L., Brandle, R., Delean, S., Paton, D. C. and Moseby, K. E. (2018) “Supportive release techniques provide no reintroduction benefit when efficacy and uptake is low,” Oryx. Cambridge University Press, pp. 1–9. https://www.cambridge.org/core/journals/oryx/article/supportive-release-techniques-provide-no-reintroduction-benefit-when-efficacy-and-uptake-is-low/E05E87ED54C7A3A8297BB2175892C251
Al Glen - firstname.lastname@example.org
Glen, AS and Veltman, CJ (2018). Search strategies for conservation detection dogs. Wildlife Biology 2018, wlb.00393 http://www.bioone.org/doi/abs/10.2981/wlb.00393
Glen, AS, Russell, JC, Veltman, CJ and Fewster, RM (in press). I smell a rat! Estimating effective sweep width for searches using wildlife detector dogs. Wildlife Research http://www.publish.csiro.au/WR/justaccepted/WR18021
Tracey Kreplins - email@example.com
Kreplins T.L., Kennedy M.S., Adams P., Bateman P.W., Dundas S.J., and Fleming P.A., (2018) Corvid interference with Canid Pest Ejectors in the southern rangelands, Ecological management and restoration, 19 (2), 169-172 https://onlinelibrary.wiley.com/doi/abs/10.1111/emr.12307
Tarnya Cox - firstname.lastname@example.org
Wells K., Fordham D.A., Brook B.W., Cassey P., Cox T., O'Hara R.B. & Schwensow N.I. (2018) Disentangling synergistic disease dynamics: implications for the viral biocontrol of rabbits. Journal of Animal Ecology, https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.128711
Greg Baxter - email@example.com
Holly P Jones, Karl J Campbell, Angela M Bourke, Greg S Baxter, Chad C Hanson & Russell M Mittermeier, 2018. Introduced non hominid-primates impact biodiversity and livelihoods: priorities for management. Biological Invasions https://doi-org.ezproxy.library.uq.edu.au/10.1007/s10530-018-1704-5
Doug Armstrong - D.P.Armstrong@massey.ac.nz
Armstrong, D.P., et al. (2018) Subtle individual variation in indeterminate growth leads to major variation in survival and lifetime reproductive output in a long-lived reptile. Functional Ecology 32: 752-761. https://onlinelibrary.wiley.com/doi/abs/10.1111/1365-2435.13014
Drummond, F.M., Lovegrove, T.G., Armstrong, D.P. (2018) Combining data-derived priors with post-release monitoring data to predict persistence of reintroduced populations. Ecology & Evolution https://www.ncbi.nlm.nih.gov/pubmed/29988454
Parlato, E.H., Armstrong, D.P. (2018) Predicting reintroduction outcomes for highly vulnerable species that do not currently coexist with their key threats. Conservation Biology https://onlinelibrary.wiley.com/doi/abs/10.1111/cobi.13096
Williams, E.M., Armstrong, D.P., O’Connell, C.F.J. (2018) Modelling variation in calling rates to develop a reliable monitoring method for the Australasian Bittern Botaurus poiciloptilus. Ibis https://onlinelibrary.wiley.com/doi/pdf/10.1111/ibi.12611
Armstrong, D.P., et al. (2017) Using Bayesian mark-recapture modelling to quantify the strength and duration of post-release effects in reintroduced populations. Biological Conservation 215:39–45 http://dx.doi.org/10.1016/j.biocon.2017.08.033
Taylor G., Canessa, S., Clarke, R.H., Ingwersen, D., Armstrong, D.P., Seddon, P.J., Ewen, J.G. (2017). Is reintroduction biology an effective applied science? Trends in Ecology and Evolution 32:873-880 http://dx.doi.org/10.1016/j.tree.2017.08.002
Rolf Schlagloth - firstname.lastname@example.org
Schlagloth, R., Santamaria, F., Golding, B. and Thomson, H., 2018. Why is it Important to Use Flagship Species in Community Education? The Koala as a Case Study. Animal Studies Journal, 7(1), pp.127-148. http://ro.uow.edu.au/asj/vol7/iss1/7
Amy Northover - A.Northover@murdoch.edu.au
Northover, A.S., Godfrey, S.S., Lymbery, A.J., Wayne, A.F., Thompson, R.C.A., 2018. The hidden consequences of altering host-parasite relationships during fauna translocations. Biological Conservation 220: 140-148. https://doi.org/10.1016/j.biocon.2017.12.037
Trish Fleming - T.Fleming@murdoch.edu.au
TL Kreplins, MS Kennedy, SJ Dundas, PJ Adams, PW Bateman, PA Fleming. 2018. Corvid interference with Canid Pest Ejectors in the southern rangelands of Western Australia. Ecological Management & Restoration 19 (2), 169-172 https://onlinelibrary.wiley.com/doi/abs/10.1111/emr.12307
PA Fleming, PW Bateman. 2018. Novel predation opportunities in anthropogenic landscapes. Animal Behaviour 138, 145-155 http://doi.org/10.1016/j.anbehav.2018.02.011
ML Martin, PW Bateman, CH Auckland, DW Miller, NM Warburton, AL Barnes, PA Fleming. 2018. Is there evidence for a trade-off between sperm competition traits and forelimb musculature in the western grey kangaroo? Biological Journal of the Linnean Society 123 (2), 431-444 https://doi.org/10.1093/biolinnean/blx151
SJ Dawson, PJ Adams, KE Moseby, K Waddington, HT Kobryn, PW Bateman, PA Fleming. 2018. Peak hour in the bush; linear anthropogenic clearings funnel predator and prey species. Austral Ecology 43, 159-171 https://onlinelibrary.wiley.com/doi/abs/10.1111/aec.12553
A Wolfe, P Bateman, P Fleming. 2018. Does urbanisation influence the diet of a large snake? Current Zoology 64 (3), 311-318 https://academic.oup.com/cz/article/64/3/311/3895746
SJ Dundas, PJ Adams, PA Fleming. 2018. Population monitoring of an endemic macropod, the quokka (Setonix brachyurus), in the northern jarrah forest, Western Australia. Australian Mammalogy 40 (1), 26-35 https://www.publish.csiro.au/am/pdf/AM16033
GL Bryant, HT Kobryn, GESJ Hardy, PA Fleming. 2017. Habitat islands in a sea of urbanisation. Urban Forestry and Urban Greening 28, 131-137 https://www.sciencedirect.com/science/article/pii/S1618866717302492
SE Allsop, SJ Dundas, PJ Adams, TL Kreplins, PW Bateman, PA Fleming. 2017. Reduced efficacy of baiting programs for invasive species: some mechanisms and management implications. Pacific Conservation Biology 23, 240-257 www.publish.csiro.au/PC/pdf/PC17006
PW Bateman, PA Fleming. 2017. Are negative effects of tourist activities on wildlife over-reported? A review of assessment methods and empirical results. Biological Conservation 211, 10-19 https://www.sciencedirect.com/science/article/pii/S0006320717307711
JL Forbes-Harper, HM Crawford, SJ Dundas, NM Warburton, PJ Adams, PW Bateman, MC Calver, PA Fleming. 2017. Diet and bite force in red foxes: ontogenetic and sex differences in an invasive carnivore. Journal of Zoology 303, 54-63 https://onlinelibrary.wiley.com/doi/full/10.1111/jzo.12463
PA Fleming, PW Bateman. 2017. Scavenging opportunities modulate escape responses over a small geographic scale. Ethology 123 (3), 205-212 https://onlinelibrary.wiley.com/doi/full/10.1111/eth.12587
PW Bateman, PA Fleming, AK Wolfe. 2017. A different kind of ecological modelling: the use of clay model organisms to explore predator-prey interactions in vertebrates. Journal of Zoology 301 (4), 251-262 https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/jzo.12415
JW Macgregor, CS Holyoake, SA Munks, JH Connolly, ID Robertson, PA Fleming, KS Warren. 2017. Investigation into individual health and exposure to infectious agents of platypuses (Ornithorhynchus anatinus) in two river catchments in northwest Tasmania. Journal of Wildlife Diseases 53 (2), 258-271 http://www.bioone.org/doi/10.7589/2015-12-335
T Worrell, R Admiraal, PW Bateman, PA Fleming. 2017. Are tourism and conservation compatible for ‘island tame’ species? Animal Conservation 20, 155-163 https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/acv.12301
LE Valentine, MR Bretz, KX Ruthrof, R Fisher, GESJ Hardy, PA Fleming. 2017. Scratching beneath the surface: bandicoot bioturbation contributes to ecosystem processes. Austral Ecology 42, 265-276 https://onlinelibrary.wiley.com/doi/full/10.1111/aec.12428
This newsletter reflects the opinions of the author(s) but not necessarily those of the AWMS Committee or membership. AWMS makes no claim as to the accuracy of stated claims and any party using this information does so at their own risk.