Spatial Pattern of Bird-Dispersed Seed Rain ofDaphniphyllum macropodum in an Evergreen Broad-Leaved Forest

Abstract

We investigated how the locations of conspecific fruiting trees, other fruiting species, and canopy gaps affected spatial patterns of bird-dispersed seed rain for a common ornithochorous tree: Daphniphyllum macropodum.In a mature evergreen broad-leaved forest in southwestern Japan, seed rain was monitored with seed traps in a 1.2 ha plot on a site with a generally closed canopy. Many of the bird-dispersed seeds of D. macropodumwere concentrated near the conspecific fruiting trees, while other seeds were scatter-dispersed. The spatial distribution of scatter-dispersed seeds was independent of the distance from conspecific fruiting trees. The scatter-dispersed seed rain of D. macropodumwas biased by abundant and widely distributed fruiting trees of Cleyerajaponica.Other rare fruiting species and canopy gaps had no clear effect on the seed rain of D. macropodum.Results show that the spatial pattern of bird-dispersed seed rain in this forest is affected by the location of fruiting trees of the same and different ornithochorous species rather than by canopy gaps.