Diverse land-uses shape new bird communities in a changing rural region

Abstract

Rural landscape change as a consequence of human population growth is a major challenge for nature conservation in the twenty-first century. Rural regions are globally experiencing change driven by diverse factors, including agricultural intensification, new agricultural commodities, residential development, and land abandonment. Understanding how different land-use trajectories affect biodiversity is critical for making informed decisions for the conservation of species in modified environments. We examined the impact of different land-uses on bird communities in the western Strzelecki Ranges, a formerly forested but now rural region in south-east Australia. We selected 25 study landscapes, each 1 km2, representing seven land-uses typical of rural regions: townships, lifestyle properties (low-density acreages or hobby farms), dairy farming, beef grazing, horticulture, tree plantation and natural forest. Terrestrial birds were systematically surveyed at 10 sites in each study landscape and the results pooled to represent the whole landscape. We recorded 80 native and 8 exotic species of birds, of which 46 species were classified a priori as forest species typical of the region. Different trajectories of land-use have generated variation in landscape structure, with a primary gradient of change from forest to rural townships. The composition of bird communities and the richness of four species-response groups showed marked differences across land-use types. The mean richness of forest species, for example, was greatest in natural forest land-use (30.0 species) and lowest in dairy farming land-use (14.5 species). Key lessons from this study include: (1) these diverse land-uses, typical of rural regions, are creating novel assemblages of birds that differ from that of the former forested environment; (2) land-use in this region is dynamic and so further re-assortment of bird communities can be expected through time; (3) despite such change, a component of the original forest avifauna persists, even in highly modified landscapes; and (4) each land-use type offers opportunities for nature conservation while also meeting the needs of people and agricultural production.