Faculty of Science, Engineering and Built Environment
School of Life and Environmental Sciences
Species habitat selection: what influences choice, what are the costs, and how do they respond to change?
Participants: Dr Euan Ritchie (PI), Dr John Arnould (CIE), Dr Jenny Martin (University of Melbourne)
Aims and background: A species' habitat selection and use depends on many factors, including resource availability, habitat structure, connectivity and interactions with other species. Variation in any or all of these factors will influence not only which areas species inhabit but also their movement patterns, energy expenditure and, therefore, key life history traits. It is well known that habitat fragmentation and/or resource availability affect species' movement patterns. In contrast, there is surprisingly little information on how these translate into energetic costs and/or behavioural modifications and how they affect growth, reproduction and survival, which raises a number of questions. In particular, what are the energetic costs of moving through habitats of differing shape (linear versus round) and/or quality (resource rich or poor)? How are movement patterns affected by interspecific interactions such as competition and/or predation? Do generalist and specialist species show different responses? How do differences between individuals and sexes affect populations? This study, therefore, will simultaneously investigate the habitat preferences, population biology, spatial movement patterns and behavioural energetics of two closely related species, the common brushtail possum (Trichosurus vulpecula) and the mountain brushtail possum (T. caninus), a generalist and specialist, respectively, across a broad habitat gradient.
Scientific significance and innovation: Our understanding of species-habitat relationships is restricted by an often narrow and incomplete focus. Our study will be truly interdisciplinary, integrating aspects of behavioural, community, landscape and population ecology, as well as physiology (including 'biologging' technology), remote camera trapping and GIS-based analyses. Through our approach, we will provide new insights into the ways species use habitats and may respond to environmental change, both at the species and individual level.
Potential national benefit and strategic alignment with the aims of the CIE: Our project addresses the National Research Priority 'An Environmentally Sustainable Australia' and its priority goals Responding to climate change and variability and Sustainable use of Australia's biodiversity. Arboreal mammals such as Trichosurus spp. are among our most threatened native wildlife due the combined effects of fire, habitat destruction and modification, and future climate change. We will provide the information required to better inform the conservation and management of these species and their ecosystems. Our study clearly fits within the CIE's three stated focal areas, by examining environmental impacts on individuals, determining how these responses lead to population and community changes and whether this promotes evolutionary change.
