Electronic versions

  • Simon Valle
    Manchester Metropolitan University
  • Nuno Barros
    Portuguese Society for the Study of Birds
  • Ivan Ramirez
    BirdLife International, Brussels, Belgium
  • Ross M Wanless
    BirdLife South AfricaUniversity of Cape Town
The Tinhosas islands, in São Tomé e Príncipe, host the most important seabird breeding colony in the Gulf of Guinea, but information on its conservation status was hitherto unpublished or anecdotal, the last assessment having been performed in 1997. A two-day expedition to the Tinhosas islands was undertaken to estimate the status of breeding seabirds in 2013. Four of the five seabird species known to breed in São Tomé e Príncipe, namely Brown Booby Sula leucogaster, Sooty Tern Onychoprion fuscatus, Brown Noddy Anous stolidus and Black Noddy Anous minutus, occur on the Tinhosas. A decrease of 80% in Brown Booby numbers, possibly due to occasional exploitation, and a 30% increase in Sooty Tern and Black Noddy numbers, were found compared to 1997 data although survey methods differed. Breeding of Brown Noddy and Madeiran Storm-petrel Hydrobates castro remains unconfirmed. Our estimates confirmed that BirdLife International Important Bird and Biodiversity Area criteria are met for at least one species, the Sooty Tern. The islands are not legally protected, nonetheless, apart from moderate levels of disturbance by fishermen who land on Tinhosa Grande, no alien species were seen, and no immediate threats to the Tinhosas colony were detected. Multiple visits within and between years are recommended, to census breeders, monitor threats and establish breeding phenologies.
Original languageEnglish
Pages (from-to)209-215
JournalOstrich - Journal of African Ornithology
Volume87
Issue number3
DOIs
Publication statusPublished - 2016
Externally publishedYes
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