Honours projects

The malleefowl (Leipoa ocellata) are members of the Megapodiidae, a family characterised by the building of mounds in which eggs are incubated. These mounds incorporate leaf litter and other plant debris, which decomposes and releases heat, warming the interior of the mound. Malleefowl mounds can be several metres wide and over one metre high. The birds continuously rake litter into the mound, thereby reducing the amount of litter in the surrounding area. The mound is used by a pair of birds for several years.

However, over time, litter around the mound is ‘used up’. The birds will then construct another mound elsewhere, but may resume using an abandoned mound when sufficient litter has re-accumulated around it.

The relationship between malleefowl mound building and litter dynamics is apparently unstudied. One interesting aspect of this relationship is how mound building affects fuel loads and fire potential. The reduction in the litter fuel load around mounds is likely to reduce the probability of the area burning. If the area around mounds escapes fire when the surrounding landscape burns, the vicinity of mounds will differ markedly in terms of vegetation structure and faunal habitat availability. While mound building effects will be localised, the presence of mounds dotted across the Mallee may contribute to increased landscape heterogeneity.

• To what degree and over what area do malleefowl alter litter fuel loads?
• What does this mean for fire behaviour around mounds?
• Does the vegetation around mounds vary from the landscape generally due to decreased fire, increased soil disturbance or altered nutrient cycling around mounds? What does this mean for fauna habitat in the area around mounds.

The swamp skink (Egernia coventryi) is a medium sized skink that is found in swamps and wet heaths in southern Victoria. It is listed as vulnerable under state legislation. Swamp skink has been recorded at Cardinia Reservoir, a Melbourne Water-managed storage reservoir in the Dandenong ranges. Melbourne Water environmental managers are keen to receive information on the population, distribution and ecology of the skink in this area. This will assist them in implementing measures to ensure the swamp skink population is maintained. 

• What habitats does swamp skink occur within?
• What are the key features of these habitats that make them suitable for the species?
• How has past and current management affected swamp skink distribution?

Fire and herbivory are both major shapers of vegetation structure and composition, and therefore can have major effects on ecosystem function. Furthermore, the interaction of fire and herbivory can produce outcomes that are difficult to predict by considering their individual effects. In a number of systems vertebrate herbivores have been found to be attracted to recently burnt areas, where more nutritious food is available.

The major vertebrate herbivores in the Mallee region are kangaroos, goats and rabbits. Anecdotal evidence suggests herbivory by these species is more intense in recently burnt areas, but this idea is largely untested. This study will seek to clarify aspects of fire-herbivore interactions in the Mallee. 

• Are herbivore abundance and/or impacts greater in more recently burnt areas?
• What are the implications of planned burning designs for the distribution of herbivores?
• What are the impacts of post-fire herbivory on vegetation? 

This study will investigate the net effect of a major wildfire on hollow abundance. 

• What is the ratio of hollows in standing and fallen trees in relation to variation in fire severity?
• Does planned burning prior to wildfire influence any effect of the latter on hollow survival?

Fire brings about major changes in habitat structure, which may render areas uninhabitable for fauna for a period after its occurrence. However, most fires are heterogeneous to some degree, such that within the fire boundary unburnt or less severely burnt patches remain. These patches may act as refuges that allow animals to survive the passage of the fire itself and/or survive in the post-fire landscape, therefore playing a crucial role in post-fire recolonisation of the landscape. 

Many factors are likely to influence whether an unburnt patch actually plays this refuge role, including size, proximity to other refuges and the inherent features of the patch. However we have little detailed information on what makes an unburnt patch a refuge for most species. 

A recent experimental burn in the Mallee provides the opportunity to examine a number of questions about faunal survival and recolonisation in the wake of fire, including the nature and function of fire refuges. The focus would be on small animals such as lizards and small mammals. 

Co-supervisor: Mr Gonzalo Crosa (Research Scientist, Programa Nacional de Investigación en Producción Forestal (INIA), Tacuarembó, Uruguay) 

This project will provide explanations for this apparent change in host specificity. Students will be required to spend 3-4 months conducting experimental work in Uruguay. Costs associated with air travel and accommodation in Uruguay are being met by INIA. 

An August 2013 start is preferable to a February 2013 start. 

Ash from bushfires has been reported as an important source of nutrients for re-sprouting eucalypts with beneficial implications for populations of insect herbivores. However, field studies proposing the occurrence of such interactions have not controlled for the confounding influences of a change in foliage type (coppice versus adult leaves) versus plant access to elevated soil macronutrients on leaf quality for herbivores; this can only be teased apart through experimental studies. 

An August 2013 start is preferable to a February start.