Abstract
Habitat constructions, including four biotope ponds, near-natural streams and four artificial floating islands, were performed in a dam lake (Higashi-Arakawa dam lake, Shioya-Cho, Tochigi prefecture) in central Japan. The purpose of these constructions was to improve the dam lake environment as habitat for wildlife. Around these ponds and streams, trees were also planted to improve habitat quality for forest-living species. We chose birds as index of bio-diversity, and monitored them for nearly six years, before and after these constructions. Before habitat creation, the site was a mildly sloped area donimated by annual plants and the area was dominated by ‘openland’ bird species. The monitoring results indicated that both the number of species and birds increased after the habitat creation, and that many wetland and forest birds appeared and used the site for foraging, resting and nesting.
