A revised bird checklist for the oceanic islands of the Gulf of Guinea (Príncipe, São Tomé and Annobón)

We present an updated bird checklist for the oceanic islands of the Gulf of Guinea. Their avifauna comprises 146 confirmed species, an increase of 19% in 15 years. Of these, 66 are resident landbird species (32 on Principe, 50 on Sao Tome and 11 on Annobon), including 29 endemic species, 17 endemic subspecies and 17 possibly non-native species. The remaining avifauna consists of six breeding seabird species, four non-breeding migrants, 62 vagrants and eight species of uncertain status. An additional 51 species have been reported but lack confirmation. Most recent changes reflect increases in observer activity and involve vagrant and unconfirmed species, but a few result from previously overlooked historical records and taxonomic changes. Of the three islands, most changes affected the avifauna of Principe, whereas little new information has come from Annobon. Future changes are predicted to arise from new reports and confirmation of vagrants, but also from further taxonomic revision of residents.