Establishment of Forest Management System for Coexistence with Decreasing Golden Eagle Population.

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1.A total home range of a surveyed pair of Golden eagle at southern part of the Kitakami Plateau in Iwate Prefecture was 84 km^2, and hunting home range of the pair was about 30 km^2. In them, area fit for hunting(ex ; low shrub grassland) of Golden eagles was only 1-3km^2. It was thought as a cause such that the Golden eagle pair showed low breeding success rate as 10% or so.2.Foods of Golden eagles observed at the Kitakami Plateau were primarily hare(Lepus brachyurus), copper pheasants(Syrmaticus soemmerringii), and snakes. These composition was not different between two periods of 1970-1990 and 2003-2005.3.At one of two experimental areas where row thinning in young conifer forest were conducted, a Golden eagle made diving into the row to catch a food animal. But hunting behaviors were observed rarely in these row thinning area compared with other areas fit for hunting.4.In order to clarify an effect of row thinning on inducing foraging activity in golden eagle, we monitored occurre … More nce of eagle and amount of its principal prey, i.e., Japanese hare and snakes on cut-over and two control sites before and after thinning for three years. The amount of hare increased remarkably in 2003 after thinning, but thereafter turned to decrease in 2004 and finally returned to density level before thinning in 2005. As for snakes, there was no detectable effect in number between cutover and control sites throughout study period. However, making gap might have an effect on inducing snakes, since all snakes found on cutover were only in cutting lines. By contrast, no apparent effect by row thinning was recognized on occurrence frequency and foraging activity of eagle.5.In southern Kitakami highland area, understory vegetation was monitored for three years after row thinning, and food plant species of Japanese hare and their preference of plant species were estimated by plant DNA analysis from fecal pellets and feeding marks on plant shoots. These results suggested that preference of plant species and plant height should be considered for hare food evaluation. Individual identification using fecal DNA analysis was carried out from fecal pellets collected in research area and its surroundings. As a result, the population density of hare was estimated about 7.3 individuals per square km. (97 words) Less