Forestry and wildlife conservation on Amami Oshima, Japan: An integrated study of wildlife and human society.

摘要

Amami Oshima has several rare species of forest wildlife, while their original habitat has been replaced by young secondary forest and logged areas extensively for the last few decades. The present study describes effects of forest cutting on the abundance of wildlife as well as characteristics of forestry and local society, and formulates solutions to the problem of forestry and wildlife conservation.The economy of Amami Oshima is largely dependent on government subsidies, of which subsidies from the national government are exceedingly important. Most of the forests are planned to be felled with a 35 to 40 year rotation cycle primarily for pulpwood production. The most important role of forestry is to provide jobs to the people working for forestry and construction companies.The abundance of 20 species of birds and five species of mammals was compared among four stages of succession logged areas, young secondary forest, old secondary forest and primary forest. All the rare species but the Amami rabbit (Pentalagus furnessi) are likely to display negative effects from logging, but the degree of harm varies considerably among species. The purple jay (Garrulus lidthi) and spinous rat (Tokudaia osimensis) were almost as numerous in young secondary forest as in older forest. The White's thrush (Zoothera dauma) and long-haired rat (Rattus legata) are, in contrast, found almost exclusively in uncut forest or forest selectively cut more than 50 years ago. Insectivorous birds were also with few exceptions negatively affected by a loss of old forest.The man-wildlife relation has been degraded by logging, because a great majority of valuable species was found to be almost exclusively dependent on primary forest and old secondary forest. All the species whose existence is rather costly to society appeared to maintain a nearly constant population level or to have become more numerous along with substantial decrease in the area of old forest. It was concluded that the most practical solution was increase in felling-age, accompanied by shift of the emphasis of the use of subsidies from building logging roads to improvement of silviculture and logging operations.