Amami Oshima (Island of Amami) in Japan has five species and two supspecies of animal wildlife that are designated as natural monuments by the national government. However, government subsidy has indirectly induced population decline of some of them through habitat destruction. Self-supporting industries make up only a small portion of the whole economy of Amami Oshima, so that financial support from the national and prefectural governments has been necessary to create a large number of jobs for local people.
Forestry has been subsidized by the central governments to a large degree. As a result of cost-reduction in logging through the subsidy which has been devoted mostly to construction of logging roads, most original forests have been replaced by young secondary forests and logged areas in the central part of Amami Oshima, where all the wildlife taxa under consideration are to be observed at present. The governments have planned to manage these young forests with a 35–40 years' rotation-cycle for pulpwood, of which the commercial value is relatively low.
Of the involved seven species and subspecies, the Great White's Thrush (Turdus dauma amami), Owston White-backed Woodpecker (Drendrocopos leucotos owstoni), and the Long-haired Rat (Rattus legata), appeared to be so dependent on mature forest (uncut for at least 40 years after selective felling) that they will probably not be able to maintain their populations if all the old forests are cut down. Small populations of the Ryukyu Robin (Erithacus komadori) may be able to survive in young secondary forests, but population decline will be substantial through the decrease in the area of mature forest. On the other three species—the Amami Rabbit (Pentalagus furnessi), Purple Jay (Garrulus lidthi), and Spinous Rat (Tokudaia osimensis)—the effects of clear-cutting of the mature forests are less obvious. Further decreases in the area of mature forests will probably cause a significant reduction in the present population-level of the Amami Rabbit, but negative effects of logging on the other two species should not be very serious. An increase in the length of rotation-cycles, and changes in the use of the subsidy, are proposed for improving the wildlife habitat and the economic efficiency of local forestry.