Surveys of the population of feral raccoons and their habitat use, begun in 2000 and 2001, were continued in 2002. Four study locations in the Yufutsu Hills were added to 11 study locations in Maoi-Nopporo Hills, and Iwamisawa-Kurisawa Hills. From May to October live traps were set at 400-500m intervals at each location for 21 consecutive nights. A total of 280 raccoons were caught, including 173 adults (104 females, 65 males) and 107 young. The number of raccoons caught has decreased from year to year, except in Nopporo Hills in 2001 and in Maoi Hills, Iwamisawa-Kurisawa Hills. The continued reduction in numbers is thought to be related to the catching effort in recent years. The total population was estimated to be 352 (204 adults and 107 young), being 25% greater than the numbers caught. In Hokkaido, yearling raccoons are considered to leave their mothers during late June, thus controlling raccoons, including removing nursing females by June, is deemed effective in causing the death of yearlings by starvation. Raccoon habitat use was analyzed using the Quantification II method, with data from 1,057 samples in 2000, 2001, and 2002. Outside variables were divided into three categories: 1) no catch; 2) one catch, and 3) two or more catches. The general environmental factors considered were land use, forest type, vegetation type, vegetation density, water availability, distance from sheds or houses, catching periods and years. Factors with the greatest influence, though differing from year to year, were: land use, water availability, distance from sheds, and catching periods. Among these, the most important were: the extent of borders between forests and rice fields; the extent of forest borders in rice field areas within the land use factor; the presence of large ponds within the water availability factor; and being within 100m of sheds or houses.
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