Status and distribution of Pacific Brent Geese Branta Bernicla nigricans wintering in Japan

Abstract

Seasonal abundance and distribution of Pacific Brent Geese wintering in Japan were assessed by examining data collected on a monthly basis by the Japanese Association for Wild Geese Protection over six winters (1989-90 to 1994-95). Peak numbers of up to 4,000 Brent Geese occurred at two sites in eastern Hokkaido each October. By January none remained in this area and only 300-500 stayed in Japan at wintering sites in southern Hokkaido and northern Honshu. An examination of data collected during an annual January census by the Environment Agency of Japan suggested that these numbers have changed little over the last 25 years and there is no evidence of a decline. In January and February 1995 we surveyed 717 km of coastline in northern Japan to try and locate the remaining population, but found only another 162 individuals. We speculate that the majority of Brent Geese wintering in northeast Asia migrate in late autumn from eastern Hokkaido to sites in the Korean Peninsula and in China, although during a seven day survey of the southern coastline of Korea in January 1996 we found only 19 Brent Geese.