Informing the space between zero and one: a standardised, scat-based approach to monitoring changes in habitat use by brush-tailed rock-wallabies (Petrogale penicillata)
Stephen Phillips A C , Katherine Howard B and Jade Krause AA Biolink Ecological Consultants, PO Box 3196, Uki, NSW 2484, Australia.
B NSW Department of Planning, Industry and Environment, PO Box 488G, Newcastle, NSW 2300, Australia.
C Corresponding author. Email: steve@biolink.com.au
Australian Mammalogy 44(1) 161-168 https://doi.org/10.1071/AM20056
Submitted: 5 February 2020 Accepted: 26 March 2021 Published: 23 June 2021
Abstract
Rock-wallabies occupy outcrops, escarpments and cliffs that incorporate structurally complex refuges; because of this, local populations present methodological challenges for monitoring purposes. We describe the development and adaptive modification of a survey technique intended to measure changes in rock-wallaby activity on a site-by-site basis. Twenty spatially independent field sites were collectively sampled across two geological strata using transects consisting of regularly spaced sampling points, with concentric series of fixed-radius circular plots at each sampling point used to count numbers of fresh/recent and/or older rock-wallaby scats. The presence/absence of fresh and/or recently deposited scats was identified as likely to be the more sensitive measure of changing use. Indexes of Activity (IoA) at each field site were subsequently obtained by transect-based sampling at 10 m intervals using 2 m fixed-radius circular plots and recording the presence/absence of fresh/recent scats therein. Derived rock-wallaby IoA ranged between 0.13 and 0.94 across the 20 sites and were approximately normally distributed. Central tendency measures associated with the IoA metrics imply some potential to develop management-themed activity thresholds. Further refinement and potential applications of the approach are discussed.
Keywords: brush-tailed rock-wallaby, conservation, detection probability, habitat use, index of activity, macropod, Petrogale penicillata, survey, threatened species management, wildlife monitoring.
References
Anderson, D. R. (2001). The need to get basics right in wildlife field studies. Wildlife Society Bulletin 29, 1294–1297.Bayne, P. (1994). Behaviour of the brush-tailed rock-wallaby, Petrogale penicillata, and the recognition of individuals. M.Nat.Res. Thesis, University of New England, Armidale.
Biolink (2020). Brush-tailed rock-wallaby monitoring: Flinders Goolman Conservation Estate. Final report to Ipswich City Council. Biolink Ecological Consultants, Uki, NSW.
Bluff, L. A., Clausen, L., Hill, A., and Bramwell, M. D. (2011). A decade of monitoring the remnant Victorian population of the brush-tailed rock-wallaby (Petrogale penicillata). Australian Mammalogy 33, 195–201.
| A decade of monitoring the remnant Victorian population of the brush-tailed rock-wallaby (Petrogale penicillata).Crossref | GoogleScholarGoogle Scholar |
Caughley, G. (1974). Bias in aerial survey. The Journal of Wildlife Management 38, 921–933.
| Bias in aerial survey.Crossref | GoogleScholarGoogle Scholar |
Caughley, G., Sinclair, R., and Scott-Kemmis, D. (1976). Experiments in aerial survey. The Journal of Wildlife Management 40, 290–300.
| Experiments in aerial survey.Crossref | GoogleScholarGoogle Scholar |
Caynes, R. (2013). The effect of fire on the brush-tailed rock-wallaby (Petrogale penicillata): A case study of Flinders–Goolman Conservation Estate. Unpublished Report. School of Geography, Planning and Environmental Management, University of Queensland.
Department of Environment & Climate Change (DECC) NSW (2008). Recovery plan for the brush-tailed rock-wallaby (Petrogale penicillata). Department of Environment and Climate Change, Sydney South.
Department of the Environment. (2020). Petrogale penicillata. In Species Profile and Threats Database, Department of the Environment, Canberra. Available at http://www.environment.gov.au/sprat [accessed 14 July 2020].
Eldridge, M. D. B., Browning, T. L., and Close, R. L. (2001). Provenance of a New Zealand brush-tailed rock-wallaby (Petrogale penicillata) population determined by mitochondrial DNA sequence analysis. Molecular Ecology 10, 2561–2567.
| Provenance of a New Zealand brush-tailed rock-wallaby (Petrogale penicillata) population determined by mitochondrial DNA sequence analysis.Crossref | GoogleScholarGoogle Scholar |
Fryxell, J. M., Sinclair, A. R. E., and Caughley, G. (2014). ‘Wildlife Ecology, Conservation, and Management.’ 3rd edn. (John Wiley & Sons Ltd.)
Gowen, C., and Vernes, K. (2014). Population estimates of an endangered rock-wallaby (Petrogale penicillata) using time-lapse photography from camera traps. In ‘Camera Trapping: Wildlife Management and Research’. (Eds P. Meek, P. Fleming, G. Ballard, P. Banks, A. Claridge, J. Sanderson and D. Swann.) pp. 61–68. (CSIRO Publishing: Melbourne.)
Ipswich City Council. (2017). Brush-tailed rock wallaby recovery plan. Available at http://www.ipswich.qld.gov.au/about_ipswich/environment/wildlife/significant-flora-and-fauna [accessed 15 July 2020].
Jarman, P. J., and Capararo, S. M. (1997). Use of rock-wallaby faecal pellets for detecting and monitoring populations and examining habitat use. Australian Mammalogy 19, 257–264.
Lethbridge, M. R., and Alexander, P. J. (2008). Comparing population growth rates using weighted bootstrapping: guiding the conservation management of Petrogale xanthopus xanthopus (yellow-footed rock-wallaby). Biological Conservation 141, 1185–1195.
| Comparing population growth rates using weighted bootstrapping: guiding the conservation management of Petrogale xanthopus xanthopus (yellow-footed rock-wallaby).Crossref | GoogleScholarGoogle Scholar |
Murray, J. V., Low Choy, S., McAlpine, C. A., Possingham, H. P., and Goldizen, A. W. (2007). The importance of ecological scale for wildlife conservation in naturally fragmented environments: a case study of the brush-tailed rock-wallaby (Petrogale penicillata). Biological Conservation 141, 7–22.
| The importance of ecological scale for wildlife conservation in naturally fragmented environments: a case study of the brush-tailed rock-wallaby (Petrogale penicillata).Crossref | GoogleScholarGoogle Scholar |
Office of Environment & Heritage (OEH) (2016). More plants and animals to be saved from extinction – Saving our Species 2016–21. New South Wales Office of Environment & Heritage.
Piggott, M. P., and Taylor, A. C. (2003). Remote collection of animal DNA and its applications in conservation management and understanding the population biology of rare and cryptic species. Wildlife Research 30, 1–13.
| Remote collection of animal DNA and its applications in conservation management and understanding the population biology of rare and cryptic species.Crossref | GoogleScholarGoogle Scholar |
Piggot, M. P., Banks, S. C., Stone, N., Banffy, C., and Taylor, A. C. (2006). Estimating population size of endangered brush-tailed rock-wallaby (Petrogale penicillata) colonies using faecal DNA. Molecular Ecology 15, 81–91.
| Estimating population size of endangered brush-tailed rock-wallaby (Petrogale penicillata) colonies using faecal DNA.Crossref | GoogleScholarGoogle Scholar |
Piggott, M. P., Hansen, B., Soderquist, T., Elridge, M. D. B., and Taylor, A. C. (2018). Population monitoring of small and declining brush-tailed rock wallaby (Petrogale penicillata) colonies at the extreme of their range using faecal DNA sampling. Australian Mammalogy 40, 58–66.
| Population monitoring of small and declining brush-tailed rock wallaby (Petrogale penicillata) colonies at the extreme of their range using faecal DNA sampling.Crossref | GoogleScholarGoogle Scholar |
Sokal, R. R., and Rohlf, F. J. (2012). ‘Biometry: the Principles and Practice of Statistics in Biological Research.’ 4th edn. (W.H. Freeman & Co.: New York.)
Telfer, W. R., Griffiths, A. D., and Bowman, D. M. J. S. (2006). Scats can reveal the presence and habitat use of cryptic rock-dwelling macropods. Australian Journal of Zoology 54, 325–334.
| Scats can reveal the presence and habitat use of cryptic rock-dwelling macropods.Crossref | GoogleScholarGoogle Scholar |
Tuft, K. (2009). Brush-tailed rock-wallabies in Curracabundi National Park – distribution, threats and other fauna. Unpublished report. School of Biological Sciences, University of Sydney.
Van Dyck, S., and Strahan, R. (2008). ‘The Mammals of Australia.’ 3rd edn. (Reed New Holland: Sydney.)
Vernes, K., Green, S., and Thomas, P. (2011). Estimating brush-tailed rock-wallaby population size using individual animal recognition. Australian Mammalogy 33, 228–234.
| Estimating brush-tailed rock-wallaby population size using individual animal recognition.Crossref | GoogleScholarGoogle Scholar |
