Seed dispersal of an endangered kmeria septentrionalis by frugivorous birds in a karst habitat

Abstract

Seed dispersal and plant regeneration in particular habitats by frugivorous birds are of great concern. In this study, we recorded the bird’s seed foraging and dispersing behavior of local bird species to examine their role in dispersing seeds of Kmeria septentrionalis, an endangered tree species in a karst habitat in southwest China. Twenty-seven bird species were recorded feeding on its seeds, and fourteen bird species were confirmed as seeds dispersers. The chestnut bulbul (Hemixos castanonotus), striated yuhina (Yuhina castaniceps), scarlet minivet (Pericrocotus flammeus) were the main seed dispersers. The average seed dispersal distance was 10.69±4.97 m and 82% of the first post-foraging perching sites were located around 15 m from the mother trees. Our results suggest that the endangered tree species K. septentrionalis attracts native birds to forage and disperse its seeds in karst habitats, and that a high level of seed predation by ground-dwelling animals and microhabitat in karst unfavorable for seed germination might be the bottleneck of its regeneration rather than the lack of seed dispersers.