a1 Biodiversity and Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
a2 Percy FitzPatrick Institute of African Ornithology, DST/NRF Center of Excellence, University of Cape Town, Private Bag X3, 7701 Rondebosch, Cape Town, South Africa and Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO/UP), Campus Agrário de Vairão, 4485-661 Vairão, Portugal.
a3 BirdLife International, Wellbrook Court, Girton Road, Cambridge CB3 0NA, UK.
a4 Institute of Evolutionary Biology, Division of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK.
Recently recognised as specifically distinct, the Príncipe Thrush Turdus xanthorhynchus is endemic to the island of Príncipe in the Gulf of Guinea, West Africa. Formerly treated as conspecific with the more abundant T. olivaceofuscus from the nearby island of São Tomé, the Príncipe Thrush is considered rare and likely to be restricted to primary rainforest. A 2007 survey of Príncipe comprising 177 point transect locations covering 13 sites under different land uses (six in primary forest, three in secondary forest and four in plantations) encountered 18 individuals. Thrushes were found only in primary rainforest, where overall densities were 0.10 birds ha−1, equating to a population size of 435 individuals (95% confidence intervals: 208–913). We adjusted this estimate to take into account the fact that the highest density (0.22 birds ha−1) only occurred above 600 m, giving a final estimated population size of only 364 birds (95% confidence intervals: 186–887). In light of evidence of recent declines, possibly driven by hunting pressure, in the number of mature individuals and the limited area of occurrence of the species, the IUCN Red List category for the Príncipe Thrush should be ‘Critically Endangered’ under both criteria B1a+b(iii and v) and C2a(ii). The recent designation of the primary forests of southern Príncipe as a protected area (Parque Natural d’Obô do Príncipe) provides an opportunity for the conservation of this newly described species, which we recommend is used as a flagship for the forests as a whole.
(Received September 12 2009)
(Accepted May 13 2010)
(Online publication July 27 2010)