Bird Populations in a Mixed Eucalypt Forest Used for Production of Wood in Gippsland, Victoria

SUMMARY

Loyn, R.H. 1980. Bird populations in a mixed eucalypt forest used for production of wood in Gippsland, Victoria. Emu 80: 145–156.

Boola Boola State Forest is a forest of mixed species in the foothills of central Gippsland. It has been used as a source of sawlogs and pulpwood since 1948 and a study has been made to assess effects of this harvesting on wildlife. This paper presents results of a survey of birds from 1975 to 1977. Quantitative results were obtained mainly by mapping territories during one breeding season. Thirteen areas were compared, including gullies, mature forest on ridges and various age-classes of regrowth. This method is described and its applications and sources of error are discussed; it is suggested that mapping of territories is useful for comparing habitats in Australian temperate forests but simple transects may be just as effective for detecting changes from year to year. Simple transects and other observations were also made as part of this study.

Results suggest that harvesting mature forest reduces the populations and diversity of birds in the harvested areas. Gullies supported high populations and some species were confined to gullies but others avoided them. The succession of bird species as forest regenerates is described; a few open-country birds enter in the early stages but after about ten years stands are populated by common forest birds. Some species do not return for much longer and appear to need nature forest. At Boola Boola twenty-five to thirty per cent of the forest remains in a mature condition (including major gullies) and most species have survived. A list of species with their habitats is given and implications for management are discussed briefly.