Habitat fragmentation continues apace, despite the well documented adverse effects to wildlife. One of the greatest threats to species persistence is reduced connectivity amongst habitat patches resulting in isolation of remnant populations. Inhibited dispersal can increase the risk of local extinction through demographic- and genetic factors.
Roads and associated traffic have numerous and diverse effects on wildlife. A small number of studies have provided evidence of fragmentation of habitat and creation of barriers that limit daily movement or dispersal of wildlife. However, a vast majority of these have been conducted in North America and Europe.
Our main approach is to use traditional ecological and genetic techniques to estimate rates of movement across the landscape. We are using a combination of radiotracking and microsatellites (genetic markers sensitive enough to detect genetic differentiation in the short term and at small spatial scales) to infer the rate of movement of Squirrel gliders Petaurus norfolcensis across roads in the highly fragmented landscapes of north-central Victoria.
Squirrel gliders may be especially affected by the barrier effect of roads given their arboreal nature. They rely on connected tree canopy for movement and gaps in vegetation may have highly deleterious effects in terms of population isolation, with consequent increase in risk of local extinctions. An interesting aspect of the ecology of many arboreal marsupials in Victoria is that most of the remnant vegetation suitable for their sustainability in fact occurs along roads, giving rise to various questions on the interrelated effects of habitat connectivity, habitat configuration, road mortality and other traffic-related impacts. A substantial part of the research will focus on assessing potential mitigation measures, which will assist in the construction and management of roads that have less deleterious effects on gliders. Finally, the outcomes of this research will be integrated into population viability modelling to predict effects at the population level.
see also Roads Project
