National Habitat Distribution Survey Shows Summer Birds May Be Declining in Japan

The Wild Bird Society of Japan (WBSJ), a nature conservation group, conducted a national survey on the habitat distribution of wild birds from 1997 to 2002 as part of the National Survey on the Natural Environment, commonly called the "Green Census," on commission from the Ministry of the Environment. For this survey, the WBSJ conducted field research at evenly distributed points across Japan, and also gathered further information through questionnaires. A nationwide survey of this kind has been unprecedented in Japan and so this survey constitutes a unique case.

To identify changes in distribution, the WBSJ compared data on the distribution of various bird species with data from surveys carried out 20 years ago. For example, the number of Gray-faced Buzzard- Eagles, a species commonly found in Japan during the summer, has decreased. Taking the migratory nature of birds summering in Japan as their most important characteristic, the WBSJ suspects that rampant forest fires and logging in tropical rainforests in these birds' Southeast Asian wintering grounds may be having major impacts on their populations in Japan.

Because further field surveys are needed at wintering grounds, the WBSJ is cooperating with BirdLife International to identify about 2,500 Important Bird Areas (IBA) around Asia, aiming to build a monitoring system by training local organizations near these IBA sites.



Posted: 2004/04/09 12:10:12 PM
Japanese version