This study examines inter-/intra-annual variation in community structure of a bird assemblage at the Sinjiko Green Park located on the north-western shore of the Shinjiko lake, one of the Ramsar-designated wetland sites.

We have conducted a censusing of birds several times per month since 1996 when the park was established. The census area includes different types of habit such as paddy fields, artificial wetland/lakeshore, pond and a small wetland.

The annual number of bird species recorded was in the range of 70-90 species and the cumulative number of species over the decade (2002-2012) was 170 species.　While there was little inter-annual variation in the number of species observed, the number tended to show conspicuous seasonal fluctuations (i.e. larger numbers in winter-spring than in summer).