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Most knowledge of qualitative seed dispersal by habitat specialist and generalist in disturbed habitat has been derived from studies only of trees at the seedling stage.Specialist is always considered to lose their dispersal function because of short-distance dispersal and favoring sites unsuitable for seedling establishment.But not considering various plant ontogenetic stages may lead to overweight the negative effects of specialist.In this study,we evaluated the potential contribution of post-foraging movement behavior by a specialist (Hypsipetes leucocephalus) and generalist (Urocissa erythrorhyncha) to the recruitment fate of a bird-dispersed tree (Taxus chinensis var.mairei) between two ontogenetic stages in a highly disturbed habitat.The results showed that both birds switch roles as a function of spatial scale: while the specialist dispersed most seeds within the local habitat,the generalist was exclusively responsible for between-patch and long distance dispersal.Adult yew trees,selected by both birds,supplied suitable shelter for saplings.The bamboo habitats,selected by generalist,provided a nurse role for seedlings with increasing negative effects on saplings.Comparing the spatial pattern between birds movement and yew recruitment,the results showed that the movement distance of specialist showed a higher concordance with yew seedling than did that of generalist.With plant development,the contribution of generalist increased.The generalists habitat had a higher degree of overlap with seedling habitat;In contrast,specialists habitat had a higher degree of overlap with sapling habitat.Our results suggest that distance-related and spatial-related differences between specialists and generalists play complementary roles to plant fitness between two ontogenetic stages in highly disturbed habitat.