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The Swift Parrot (Lathamus discolor), is a migratory species that forages primarily on Blue-gum (Eucalyptus globulus) during its Tasmanian breeding season. We investigated the foraging preferences of Swift Parrots for Blue-gum trees of different sizes and the effect of tree size on flowering frequency and flowering intensity over three seasons (1998, 1999, 2001). Swift Parrots showed a clear preference for larger Blue-gum trees: Blue-gum trees in which Swift Parrots foraged were ~40% larger than surrounding (non-forage) trees, while the size-class distribution of forage trees was significantly skewed towards larger tree-size compared with surrounding non-forage trees. The mean flowering intensity of forage trees was also significantly greater than the mean flowering intensity of non-forage trees. Both flowering frequency and flowering intensity increased with tree size, although there was a trend for both flowering frequency and intensity to decline in the largest tree size-classes. Past clearing has resulted in the loss of over 50% of the original (pre-European) grassy Blue-gum forest in Tasmania. Remnant grassy Blue-gum forest as well as artificially planted Blue-gum trees typically occur in small patches of

The morphology and microscopic architecture of the alimentary tract of the Swift Parrot was compared to that of the Green Rosella and Musk Lorikeet. Gut contents were evaluated grossly and by light microscopic examination. There were significant differences between the Swift Parrot and the Green Rosella in the scaled measurements of the length of the distal oesophagus and proventriculus and in the width of the crop, duodenum, intestine and cloaca. There were significant differences in the scaled measurements of the length of the gizzard and the width of the oesophagus, gizzard and duodenum between the Swift Parrot and the Musk Lorikeet. The results support previous findings that the Swift Parrot has retained some of the alimentary features of its granivorous ancestors. However, our findings suggest that the Swift Parrot may have adapted to nectarivory, not only with the development of a brush tongue, but also in changes to the crop, proventriculus and duodenum. The larger, more muscular gizzard and longer intestine may allow the Swift Parrot to use a diversity of dietary items when nectar and pollen are not readily available.

Bird communities in montane wet forest at three sites (altitudes 700,750 and 880 m) on the Central Plateau of Tasmania were surveyed over a 12-month period between December 1991 and November 1992. Monthly transect counts were carried out at each site. Snowf:,lls are common at all three sites during winter and snow can remain at the highest site for several weeks. Bird communities at the study sites showed significant differences in densities and seasonal patterns even though species composition was similar. These differences were influenced by the variation in habitats and the environments at the sites. Butlers Road, the lowest site with the mildest winters and greatest proportion of drier habitat, had the highest bird densities, while D'Arcys Bluff, at the highest altitude, had the lowest. The degree of seasonal changes of birds was similar to mainland montane wet forests, with over half the species moving either locally or to the mainland, However, there was variation in seasonal occurrences between the study sites, with proportionally more species moving from the highest site during the winter, Within the study sites, the wet forest habitats with a diverse shrub and/or fern understorey supported higher bird populations than did mixed forest and damp forest. Species richness is lower at these sites compared with equivalent montane forests on mainland southeastern Australia.

Millipedes were sampled by hand-collecting from plots and by pitfall trapping at three forest sites in central Tasmania. Seven days of pitfall trapping each month over one year was less efficient than four weeks of hand-collecting in autumn, yielding fewer species and fewer specimens per working day in the field. Hand-collecting is likely to provide more accurate data on species diversity and relative abundance for a range of litter invertebrates.

Composition of the amphipod fauna and seasonal changes in captures in pitfall traps were compared at a lowland forest in northeastern Tasmania and three sites in highland forest in central Tasmania. The number of species at the highland sites (five) was greater than for the lowland area (two), possibly due to the greater development of the litter habitat and the moister, more humid conditions at the highland sites. Capture rates were correlated with temperature, but not rainfall, at both the lowland and highland areas. However, minium temperature was most significant for the highland sites, and maximum temperature was most significant at the lowland area. Captures at the highland sites were proportionally greater in autumn and lower in summer and showed a peak in October which was not present at the lowland area. Capture rates are most likely influenced by both activity levels and population size, as determined by seasonal reproductive patterns. It is, therefore, possible that the differences in the seasonality of captures at the highland and lowland areas may be related to different patterns of reproductive activity at the different altitudes.