Encroachments on Birdland
The Environment Agency's survey divided the country into 1,563 areas of approximately 20 square kilometers (7.7 square miles) each and examined what types of small birds are breeding in each area. The results confirmed breeding activity for 375 varieties of birds but also revealed that breeding spots for several species have significantly decreased since the last survey was taken.

Of those birds that pass the winter in Southeast Asia and return to Japan from spring through summer, breeding areas for the thick-billed shrike decreased from 20 to just 1--in Honshu island's northernmost prefecture of Aomori--and areas for the brown shrike dropped from 40 to 4. Suggested causes of these declines include a worsening of the environment in the birds' wintering areas due to deforestation and other factors, as well as development of farmland and the effects of agricultural chemical use in Japan.

The number of breeding areas for such waterfowl as the grebe and Kentish plover also shrunk by half. One proposed reason for this drop-off is that the small fish that serve as a food source for these waterfowl are being eaten by black bass and other fish brought in from overseas to fill lakes and marshes for fishing.

The riverbeds, meadows, and fields where larks live and breed are declining as a result of factory construction and real-estate development in these areas. As the lark is a highly familiar bird in Japan, news of their loss of breeding areas came as a surprise to many.

Meanwhile, breeding activity by the red-billed leiothrix--a bird native to southern China and the Himalayas--which was not observed at the time of the previous survey, was confirmed this time in Ibaraki Prefecture (neighboring Tokyo) and the Kyushu region.

Copyright (c) 2000 Japan Information Network. Edited by Japan Echo Inc. based on domestic Japanese news sources. Articles presented here are offered for reference purposes and do not necessarily represent the policy or views of the Japanese Government.