Objectives and Methods : This study was made in Maoi Hills and Nopporo Hills on the outskirts of Sapporo, Hokkaido, to survey the population of feral raccoons (Procyon lotor) and to clarify their habitat. Between early July and late October, 2000, live traps were set in 9 locations within the two regions. The traps were set at 400-500-meter intervals for 21 consecutive nights in each location. This population estimate was bassed on the removal method. Population : Altogether, 237 raccoons were caught, including 153 adults (40 male, 113 female) and 84 young (48 male, 36 female). In Maoi Hills, the catch ranged from 35-45 animals in the north to 9-18 in the south. In Nopporo Hills, where control campaigns had been carried out the year before, 28 raccoons were caught in the north and 12 in the south. The total raccoon population throughout the regions was estimated at 243, closely approximating the actual number of animals captured. This estimate takes into account the raccoons that were culled. In each of the various areas, the estimated population and the actual number of animals caught were comparable, differing consistently by only 1 or 2 animals. Population density per 100 ha was estimated according to the catch and calculated for the 200-m zone surrounding the traps and for the 400-m zone surrounding the traps. In Maoi Hills, high-density areas had 4 raccoons in the 200-m zone and 3 in the 400-m zone. In Nopporo Hills, low-density areas had 3 to 0.5 raccoons in the 200-m zone and 2 to 0.5 in the 400-m zone. Habitat : The raccoon habitats were analyzed by the quantification II method. The outside variables were divided into 3 classes, namely 0 (zero), 1, and 2-or-greater, representing the number of raccoons. The general environmental factors considered were land use, forest type, vegetation type, vegetation density, water availability, and the distance from cattle sheds or houses. Land size, water, and distance from the cattle shed were shown to have the greatest effects on the presence of raccoons and on their population. The specific environmental factors that scored high were the presence of a forest next to the rice field, fields, wastelands, gardens, ponds, and a distance of 100 m or less from the cattle shed. Conclusion : These results suggest that the most suitable sites for trapping feral raccoons are places that lie within 100 meters of a cattle shed and those near the pond in a rice field.
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