An exciting opportunity exists for a PhD student to be part of a dynamic group comprising industry groups (Alcoa World Alumina Australia), government departments (Department of Conservation and Land Management) and tertiary institutions (Murdoch University and University of Western Australia) researching innovative methods for accelerating the return of fauna to restored sites and methods of managing restored sites to achieve restoration objectives. Their project will investigate the return of bats to areas restored after bauxite mining and potential management techniques for accelerating their return. The project will focus on successional processes in bat communities as restoration matures and an assessment of the value of state-and-transition models as a conceptual model to guide management of restored areas for bats, although there will be scope to expand the project into other areas. The project is field-based and will be conducted at Alcoa’s minesites, consisting of a mosaic of unmined forest and restored mine-pits of varying ages, all located within 100km of Perth in the northern jarrah forest. The northern jarrah forest is a multiple use area managed for mining, water resources, timber, recreation and conservation, so this project provides a real opportunity to conduct research that will help preserve biodiversity in multiple use landscapes. This study will complement previous research conducted on other faunal groups in restored bauxite mines and addresses an urgent need to understand responses of the south-west Western Australian bat fauna to both restoration and disturbance in general.
Click here for further information or contact Mike Craig at M.Craig@murdoch.edu.au or call (08) 9360 2605.
Morethia obscura displays a unique successional pattern in restored minepits. It rapidly recolonises minepits within 3 years but then gradually declines in abundance as the restoration matures until it eventually disappears from restored areas when they are about 20 years old. The species is very poorly known ecologically, but it is a generalist forager and forages primarily in leaf litter. Both invertebrate abundance and leaf litter cover and depth increase as restoration matures, which leaves thermal biology as the most likely explanation for the species gradual disappearance from restored areas, particularly as canopy cover increases as restoration matures. This study will investigate the thermal ecology of Morethia obscura in two ages of restoration and unmined forest to determine whether the lack of suitable basking sites in older restoration is responsible for the species’ disappearance from these areas. We will use models, supplemented with observation on free-ranging animals, to construct thermal profiles in various microhabitats across the range of forest types. This information can then be used to inform management prescriptions that will ensure the persistence of Morethia obscura in restored areas as they mature.
This study will identify patterns of microchiropteran succession in restored minesites and determine the congruence between these successional patterns and vegetation succession. These questions will be used to evaluate whether the state-and-transition models developed for vegetation succession in restored minesites, are a suitable framework for interpreting microchiropteran succession. Bat abundance will be assessed using Anabat detectors, which record ultrasonic echolocation calls of bats, and a hand-held Petterson ultrasonic detector and calculated as numbers of passes per night. Each plot will be surveyed twice to provide accurate estimates of bat abundance. We will also assess the vegetation structure at each site, measuring characteristics that are important determinants of bat community composition. In addition, we will radio-track a range of bat species (e.g. Falsistrellus mckenziei, Chalinolobus gouldii) to determine their roosting requirements. Bats will be captured in harp traps and mist nets, fitted with small radio-transmitters, and tracked to their daytime roosts. To model how long it takes restored areas to provide suitable roost sites for microchiropterans, characteristics of trees used as roosts will be recorded, as well as structural features of the vegetation where roosts are located.
The project will take existing data from other projects and use them to model landscape scale changes in vertebrate abundance as a result of vegetation succession and disturbance regimes. Spatial and temporal models will be developed based on population data, successional habitat preferences and vital attribute information for flora and fauna species. We will employ GIS to develop spatial and temporal models of fauna habitat distributions. Spatial analysis of habitat suitability will provide habitat information for management. We will help inform mine planning by determining how vertebrate populations are affected by the extent and age of restored areas in the landscape. We will also incorporate the effects of disturbance regimes in unmined forest surrounding restored areas on populations at the landscape level. Other valuable data derived from this project will be the ability to model different management options, in both restored minesites and unmined forest, at a landscape level and determine their effects on population levels of particular species.
Skirts (dead leaves that accumulate around the trunk) of grass-trees are known to be used as refuge sites by a wide range of animal species. However, these skirts are removed by fire, reducing suitable habitat for some species. The Mardo is one species that uses grass-tree skirts as daytime refugia. It is not clear, however, how critical grass-tree skirts are for Mardos, since they also show some degree of use of logs and burrows as refugia.
This project aims to evaluate the importance of grass-tree skirts for Mardos by experimentally removed grass tree skirts from burnt areas and observed any shifts in the daytime refugia used. This will be achieved by radio-tagging Mardos and determining their daytime refugia, both before and after skirt removal. Part of this project will also evaluate factors that affect the burning of grass-tree skirts and why some grass-tree skirts remain unburnt. Data from this project will be used (e.g. by the Dept. of Environment and Conservation) to evaluate the likely effects of current burning regimes on Mardo populations.
We have a number of projects that will examine the impact of P. cinnamomi on fauna (mammals, reptiles and invertebrates). We have very little understanding of how changes in plant communities due to the pathogen can impact on the viability of fauna in the long-term. We are particularly interested in areas on the south coast.