Surveys of breeding birds of Tokyo were conducted twice (1973-1978 and 1993-1997) and presented as ”The Breeding Bird Atlas of Tokyo.” From 2016 to 2021, we completed the third survey of this ...program. We set survey courses within each cell of a 1km square mesh (total 2344 courses) placed as a graticule over the map of Tokyo. During this survey period, we conducted two field surveys in the early morning of the breeding season. In addition to field surveys, literature information and bird observation records were collected and compiled to determine the status of birds in each 1km mesh cell. Aiming at serving researchers and conservationists who seek to evaluate the distribution of birds in Japan during this period, we will release this dataset by aggregating the information into 5km mesh as a means of protecting rare species.Data download: http://www.bird-research.jp/appendix/br17/tokyo5km.xlsx
We monitored the Northern Goshawk Accipiter gentilis at six sites in Japan to determine trends in the number of breeding pairs. In addition, to identify changes in the reproductive performance of ...goshawks at a wide geographic scale, breeding data was collected from via web form from observers nationwide and were analyzed regionally.From 2001 to 2021, the number of breeding pairs of goshawks at the six monitoring sites decreased significantly by 2.8%/year. From 2016 to 2021, the proportion of previously-known nests that failed to breed had increased in the Kanto and Chubu regions. Also, a significant decreasing trend in the number of fledglings was observed at 47 nests under continuous survey.On September 21, 2017, the Northern Goshawk was removed from the list of “Nationally Endangered Species of Wild Fauna and Flora” under the Law for the Conservation Endangered Species of Wild Fauna and Flora. The present results do not point to a direct effect attributable to removal from the list. Our data, however, indicates reduced breeding performance and a decline in the number of active pairs, and we recommend continued monitoring of those parameters.