Ecology, distribution and density of birds in Victorian forests.  R. H. Loyn.  November 1985.  24 pp. (unpubl.)

SUMMARY

Bird communities and populations were studied in a range of Victorian forests, from the coast across the mountains to the flood-plain of the River Murray. They are discussed in relation to the foraging ecology of common species, with comments on management and the roles of birds in controlling insects.

The main divisions in bird communities are between those of wet gullies or mountain forests, those of drier foothill forests and those of the drier forest types on the north side of the Great Dividing Range. Important features of the environment that affect the bird community include shrub structure, successional stage of the forest, presence of nectar-rich flowering shrubs, presence of arborescent wattles, abundance of tree hollows, presence of smooth-barked or rough-barked eucalypts, infestation by canopy insects and whether eucalypts are producing flows of nectar or other carbohydrate exudates. In the foothills, bird populations are higher in gullies than on ridges, and generally high where shrub layers are well-developed or where there are abundant food sources in the canopy.

Insectivorous birds play active roles in determining the health of the forest. This has been illustrated by experiments where bell miners (Manorina melanophrys^†) were translocated from unhealthy forest infested with psyllids (Glycaspis spp.). Other common birds moved in and eradicated the infestations. Various implications of this are discussed.

^†Nomenclature follows RAOU (1978).

Also published:

Loyn, R.H. (1985)  Ecology, distribution and density of birds in Victorian forests.  In Birds of the Eucalypt Forests and Woodlands: Ecology, Conservation and Management, (Eds.) A. Keast, H.F. Recher, H.A. Ford and G.A. Saunders, Surrey-Beatty and Sons Ltd, Sydney, Ch. 5.