Dr Joanne Isaac

Postdoctoral Research Associate

Research Interests

My current research is focused on extinction risk and climate change in rainforest vertebrates in the Wet Tropics Bioregion in north Queensland. Extinction risk is not usually equal across species, as particular life history and ecological traits make some species more vulnerable to extinction than others. In particular, those species with a small range size, relatively large body size within their taxonomic group, and ecological specializations such as a specialized diet and habitat requirements, are more likely to decline and go extinct than more generalist species with a faster life history. The Wet Tropics is home to a wide variety of restricted endemic vertebrate species which are likely to fall into all of these categories. My project will assess relative extinction risk in all vertebrates in the region, based on life history and ecology, and then determine how predicted climatic changes will affect this underlying risk of extinction. I am also interested in how anthropogenic factors, such as climate change, habitat modification and fire, affect individual life history traits and population dynamics.

Recent and current projects include

• Extinction risk in Wet Tropics vertebrates

• Creating a ‘supertree’ phylogeny of Australian Wet Tropics vertebrates

• Assessing the thermal preferences of an arboreal marsupial – how do tree hollows differ in their range of temperatures and humidity and could arboreal marsupials adjust their use of tree hollows in response to climate change.

The Centre for Tropical Biodiversity and Climate Change (To be linked)

Selected Publications

Williams, S.E., Isaac, J.L., Shoo, L.P. (in press) The impact of climate change on the biodiversity and ecosystem function of the Wet Tropics. In: Living in a dynamic tropical forest landscape (Eds. N. Stork & S. Turton). Blackwell Scientific.

Williams, S.E., Isaac, J.L., Moritz, C. (in press) Towards an understanding of vertebrate biodiversity in the Wet Tropics. In: Living in a dynamic tropical forest landscape (Eds. N. Stork & S. Turton).Blackwell Scientific.

Isaac, J.L., Williams, S.E. (in press) Climate change and extinctions. In: Encyclopaedia of Biodiversity (Ed. S. Levin). Elsevier Press.

Johnson, C.N., Isaac, J.L. Fisher, D.O. (2006) Rarity of a top predator triggers continent-wide collapse of mammal prey: dingos and marsupials in Australia. Proceedings of the Royal Society of London, Series B – Biological Sciences, 274 (1068): 341-346.

Isaac, J.L. (2006) Sexual dimorphism in a marsupial: seasonal and lifetime changes in sex specific mass. Australian Journal of Zoology, 54 (1): 45-50. (0.8;)

Isaac, J.L., Johnson, C.N. (2005) Terminal reproductive effort in a marsupial. Biology Letters, 1 (3): 271-275.

Isaac, J.L., Jamsranjav, J., Simpson, L. King, S.R.B. (2005) Small mammals of the Mongolian mountain steppe region near Erdensant: insights from live-trapping and raptor pellet remains. The Mongolian Journal of Biological Sciences, 3 (2): 65-70.

Isaac, J.L. (2005) Life history and demographics of an island possum. Australian Journal of Zoology, 53 (3): 195-203.

Isaac, J.L., Krockenberger, A.K., Johnson, C.N. (2005) Adaptive sex allocation in relation to life-history in the common brushtail possum. Journal of Animal Ecology, 74: 552-558.

Isaac, J.L. (2005) Mating season mass loss in male common brushtail possums, Trichosurus vulpecula: implications for age-specific variation in mating strategy. Journal of Zoology, 266: 181-185.

Isaac, J.L. (2005) Potential causes and life history consequences of sexual size dimorphism in mammals. Mammal Review, 35 (1): 101-115

Isaac, J.L., Johnson, C.N., Grabau, P.J., Krockenberger, A.K. (2004) Automated feeders: new technology for food supplementation experiments in mammals. Wildlife Research, 31 (4): 437-441.

Isaac, J.L., Johnson, C.N. (2003) Sexual dimorphism and synchrony of breeding: variation in polygyny potential among populations in the common brushtail possum, Trichosurus vulpecula. Behavioral Ecology, 14 (6): 818-822.

Contact Details

Dr Joanne Isaac

Campus: Townsville

Telephone: +61 7 4781 4439
Fax: +61 7 4725 1570
Email:Joanne.Isaac@jcu.edu.au

Note: Please direct all student enquiries through the School Secretary.