Small Mammal Surveys
Since European settlement, there has been a severe decline in mammalian fauna in temperate woodlands. This is due to the combined effects of introduced predators, such as foxes (Vulpes vulpes) and cats (Felis catus), competition for food from introduced herbivores such as domestic livestock, rabbits (Oryctolagus cuniculus) and hares (Lepus europaeus), overgrazing by native fauna, habitat loss and modification, and altered fire regimes. Small to medium sized mammals (35g - 5.5kg) have been particularly affected.
Many small ground-foraging mammals had important ecological effects such as mixing of organic material into soils, soil aeration, spreading of mycorrhizae and seeds, improved water infiltration and germination of seeds. Like elsewhere in Australia, many small mammals have become rare or locally extinct in the ACT since European settlement. The effects of woodland manipulations on surviving small mammal populations is of significant conservation interest and is a key starting point for the ecological research. In the future, reintroduction of some locally extinct species into a feral animal-proof fenced reserve at Mulligans Flat will provide added research opportunities.
Two small native mammals of conservation interest have been recorded in the Mulligans Flat – Goorooyarroo reserves or surrounding areas more recently. These are the yellow-footed antechinus (Antechinus flavipes) and the common dunnart (Sminthopsis murina). The current status of both species in these reserves is poorly known. This experiment aims to establish whether these species are still present at the experimental sites, and whether manipulations can improve the habitat for them.
Method for Survey
Since small mammal densities are low in the reserves, footprint tracking tunnels are the best survey technique. Footprint tunnels are made of plastic conduit, inside each tunnel is a plastic plate with an ink pad in the middle, and two pieces of paper on either side(see diagram). A smear of peanut butter is placed on the side of the tunnel, as an attractant above the ink pad. When the animal walks through the tunnel to the peanut butter, it gets ink on it's feet and then leaves prints on the pieces of paper. Footprints are identified using a reference collection developed by CSIRO Ecosystem Science.
then it walks over the paper at each end. Picture on the right shows a footprint tunnel paper with tracks of a Common Dunnart Sminthopsis murina