Determinants of bird species richness in public green spaces

Abstract

Capsule: Bird species richness showed consistent positive correlations with site area and rough grass. Aim To determine those features of parks and other public green spaces that are of most importance in promoting bird species richness and to use this information to make recommendations for management of these areas. Methods: Birds were counted in parks and other public green spaces within Greater London. Three survey visits were made in each of the periods summer 2002 and 2003 and winter 2002/03 and 2003/04. Habitat data were also collected. Results: Site area was the most consistently significant variable related (positively) to total species richness. There were also positive effects of waterbodies and rough grass (including nettles and weedrich areas). Species richness increased with a greater proportion of adjacent gardens in sites <1 ha in size. There were negative associations with the presence of buildings. When considered by species group (woodland species, farmland species and habitat generalists), results were very similar to those for total species richness, except that there were no significant associations with presence of waterbodies. Conclusion: Bird species richness is likely to be enhanced by increasing site area, and providing rough grass and waterbodies in urban green spaces. Such information could be especially useful in designing green spaces in new residential developments to maximize avian diversity. Surrounding habitats are also crucial determinants of bird species richness in parks. © 2007 British Trust for Ornithology.