About me
I am a wildlife ecologist. I work on projects that have a practical application – where improving our understanding of animal biology and behaviour can improve native species conservation and management.
Disturbance ecology - disturbances such as tree pathology, fire, grazing and clearing result in altered habitats for native and invasive species. Humans have also deliberately or inadvertently (e.g. artificial water points for livestock or fighting fire, improved livestock grazing) added resources to landscapes that can also benefit wildlife. The rapid growth in green energy in Australia, including solar and wind generation, will affect wildlife habitat and directly cause losses. Understanding the interactions between these disturbances and wildlife can help us to moderate the rate of change through proactive measures (e.g. the addition of artificial refuge and targeted revegetation).
Wildlife biology - Much of my career has focussed on biological understanding that will improve wildlife conservation and management. For native species, their diet, physiological and anatomical adaptations, movement ecology, and habitat selection are all fundamental to how we can conserve species. For invasive species, I have also been working on the biology of vertebrate pest species to identify their prey, understand their demographics and biology (e.g., sex ratio, survival), and contribute to developing better ways of managing them.
Stray and feral cat biology - predation by feral cats is recognised as a key threat for Australian native wildlife. Population control of cats requires knowledge about their biology that can inform modelling and therefore selection of appropriate tools. Over the last 10+ years, my students and I have carried out studies on ageing of cats, demographics, diet, anatomy (bite force and mechanics of food handling), and developing novel methods for feral cat control or mitigation of their predation impacts. This work has been fundamental to improving management of feral cats and improving conservation outcomes.
Human impact on animals - translocation, prescribed burning, and urban development are examples of how people are directly and indirectly influencing wildlife ecology, including how animals move about, their diet and survival. In some cases, animals are really good at living alongside us; understanding what they do differently or the particular resources that they use will help predict and conserve the future biodiversity of our cities.
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Organisational Affiliations
Highlights - Output
Journal article
Distinctive diets of eutherian predators in Australia
Published 2022
Royal Society Open Science, 9, 10, Art. 220792
Introduction of the domestic cat and red fox has devastated Australian native fauna. We synthesized Australian diet analyses to identify traits of prey species in cat, fox and dingo diets, which prey were more frequent or distinctive to the diet of each predator, and quantified dietary overlap. Nearly half (45%) of all Australian terrestrial mammal, bird and reptile species occurred in the diets of one or more predators. Cat and dingo diets overlapped least (0.64 ± 0.27, n = 24 location/time points) and cat diet changed little over 55 years of study. Cats were more likely to have eaten birds, reptiles and small mammals than foxes or dingoes. Dingo diet remained constant over 53 years and constituted the largest mammal, bird and reptile prey species, including more macropods/potoroids, wombats, monotremes and bandicoots/bilbies than cats or foxes. Fox diet had greater overlap with both cats (0.79 ± 0.20, n = 37) and dingoes (0.73 ± 0.21, n = 42), fewer distinctive items (plant material, possums/gliders) and significant spatial and temporal heterogeneity over 69 years, suggesting the opportunity for prey switching (especially of mammal prey) to mitigate competition. Our study reinforced concerns about mesopredator impacts upon scarce/threatened species and the need to control foxes and cats for fauna conservation. However, extensive dietary overlap and opportunism, as well as low incidence of mesopredators in dingo diets, precluded resolution of the debate about possible dingo suppression of foxes and cats.
Journal article
Published 2022
Diversity and Distributions, 28, 5, 976 - 991
Aim
Introduced predators negatively impact biodiversity globally, with insular fauna often most severely affected. Here, we assess spatial variation in the number of terrestrial vertebrates (excluding amphibians) killed by two mammalian mesopredators introduced to Australia, the red fox (Vulpes vulpes) and feral cat (Felis catus). We aim to identify prey groups that suffer especially high rates of predation, and regions where losses to foxes and/or cats are most substantial.
Location
Australia.
Methods
We draw information on the spatial variation in tallies of reptiles, birds and mammals killed by cats in Australia from published studies. We derive tallies for fox predation by (i) modelling continental-scale spatial variation in fox density, (ii) modelling spatial variation in the frequency of occurrence of prey groups in fox diet, (iii) analysing the number of prey individuals within dietary samples and (iv) discounting animals taken as carrion. We derive point estimates of the numbers of individuals killed annually by foxes and by cats and map spatial variation in these tallies.
Results
Foxes kill more reptiles, birds and mammals (peaking at 1071 km−2 year−1) than cats (55 km−2 year−1) across most of the unmodified temperate and forested areas of mainland Australia, reflecting the generally higher density of foxes than cats in these environments. However, across most of the continent – mainly the arid central and tropical northern regions (and on most Australian islands) – cats kill more animals than foxes. We estimate that foxes and cats together kill 697 million reptiles annually in Australia, 510 million birds and 1435 million mammals.
Main conclusions
This continental-scale analysis demonstrates that predation by two introduced species takes a substantial and ongoing toll on Australian reptiles, birds and mammals. Continuing population declines and potential extinctions of some of these species threatens to further compound Australia's poor contemporary conservation record.
Journal article
Diet of the introduced red fox Vulpes vulpes in Australia: Analysis of temporal and spatial patterns
Published 2021
Mammal Review, 51, 4, 508 - 527
The red fox Vulpes vulpes is one of the world’s most widespread carnivores. A key to its success has been its broad, opportunistic diet. The fox was introduced to Australia about 150 years ago, and within 30 years of its introduction was already recognised as a threat to livestock and native wildlife.
We reviewed 85 fox diet studies (totalling 31693 samples) from throughout the species’ geographic range within Australia. Mammals were a major component of fox diet, being present in 70 ± 19% of samples across n = 160 locations. Invertebrates (38 ± 26% n = 130) and plant material (26 ± 25% n = 123) were also both staple foods and often the dominant food category recorded. Birds (13 ± 11% n = 137) and reptiles (10 ± 15% n = 132) were also commonly reported, while frogs were scarcely represented (1.6 ± 3.6% n = 111) in fox diet studies.
Biogeographical differences reveal factors that likely determine prey availability. Diet composition varied with ecosystem, level of vegetation clearing and condition, and climate zone.
Sample type (i.e. stomach versus scat samples) also significantly influenced reporting of diet composition. Livestock and frogs were underrepresented in records based on analysis of scats, whereas small mammals (native rodents, dasyurid marsupials, and bats) were more likely to be recorded in studies of scats than in studies of stomach contents.
Diet varied seasonally, reflecting activity patterns of prey species and food availability. This synthesis also captures temporal shifts in fox diet over 70 years (1951–2020), as foxes have switched to consuming more native species in the wake of successful broadscale biological control of the invasive European rabbit Oryctolagus cuniculus.
Diet analyses, such as those summarised in this review, capture the evidence required to motivate for greater control of foxes in Australia. This synthesis also highlights the importance of integrated pest species management to meet biodiversity conservation outcomes.