Habitat destruction is the single biggest threat to biodiversity. Despite significant research efforts, the response of biodiversity to human activities remains difficult to' predict. This thesis analyses the responses of bird and tree assemblages to land-use intensification on the island of Sao Tome (Democratic Republic of Sao Tome and Principe), focusing on the endemic species. Global research effort on island endemic birds is very biased; over half of the research is concentrated in less than 5% of the species. Although Sao Tome has received very little research, many other endemic-rich islands have received even less. Endemic birds were associated with less intensive land-uses, although dominant across all land-uses and rather resilient to intensification. The number and abundance of non-endemic birds increased sharply with intensification; these were nearly absent in old-growth forest and they almost became dominant in non-forested land -uses. In terms of vegetation characteristics, the shift towards an endemic-depleted bird assemblage was most strongly linked to reduced canopy cover. This shift was also facilitated by degraded landscape contexts, and it is likely that the dominance of endemic birds in Sao Tome is linked to the island's high proportion of forest cover. Endemic trees overall were scarce and almost entirely restricted to forests. The lack of information surrounding the history of the island's flora does not allow clarification of whether this paucity is natural or a result of human interference.