Arboreal marsupials and nocturnal birds in thinned regrowth, unthinned regrowth and old lowland forest, East Gippsland, Victoria

Summary

The density and distribution of arboreal marsupial and nocturnal bird fauna in thinned regrowth, unthinned regrowth and old lowland forest was examined. The presence of each species recorded is influenced by the structure and species composition of the forest. Significantly higher densities of arboreal marsupials requiring hollows and undisturbed mixed eucalypt forest (Yellow-bellied Glider, Mountain Brushtail, Sugar Glider) were recorded in old forest. These species are substantially reduced in number in thinned forest. Conversely, thinned and unthinned regrowth is utilised by a range of nocturnal birds (Sooty Owl, Southern Boobook), with many smaller species (nightjars) increasing in number in thinned forest. The retention of some proportion of old trees in regrowth forest or in close proximity, is seen as critical to the maintenance nocturnal bird and arboreal marsupial species in regrowth forest. This study represents a preliminary investigation. Long term monitoring of these sites will be necessary to determine how these species and groups respond to changes in the forest after thinning, particularly if overwood and remnant stags are removed.