1999 Volume 48 Issue 2 Pages 135-144
Vegetational characteristics of 20 nest stands and 35 nest trees of the Northern Goshawk (Accipiter gentilis) were investigated in the Tokachi plain, eastern Hokkaido. Of 20 nest stands, 12 were isolated woods, 4 were shelter belt and 4 were forests, respectively. In all cases, within circular plots of 5-km in radius centered at nest sites agricultural land accounted for 47.3 to 87.8%x. Tree densities (no. of trees/ha) in nest stands were significantly lower than those in 40 woods which selected at random and have no nest. However, no difference in tree diameter at breast height and basal area were found between nest stands and random plots. The relative dominance of larch (Larix leptolepis) within nest stands was significantly higher than broad-leaved trees and evergreen conifers. Larch was used more frequently as nest trees than other tree species. There was no corre-ation between distance from nest trees to forest edge and nest stands size. Jests were usually constructed at the base of horizontal branches in conf-fers, or in large primary crotches of deciduous broad-leaved trees and were usually at the approximately half of nest tree height. There was open. space around the nests.