Hering, J., Hering H., Lima R.F & Melo. M. (2018) Little-known African bird: Príncipe White-eye Zosterops ficedulinus - a rare island endemic.The Bulletin of the African Bird Club, 25 (1), 75-81.
The Príncipe White-eye Zosterops ficedulinus is endemic to Príncipe Island, in the Gulf of Guinea, where it is confined to the best preserved forests. It is rare, frequently associated to tall trees, and among the most difficult to observe São Tomé and Príncipe endemic bird species. However, a reliable observation site has been discovered recently: between Baía das Agulhas, at the abandoned Maria Correia farm (01 ° 35'57.62 "N 07 ° 2'8.79" E), and A Mesa. We present the first pictures of this species in Nature, taken at this site in 2017. It is less strongly colored than the São Tomé White-eye Z. feae, its close relative from the nearby São Tomé Island. In addition, the latter has cinnamon feathers clearly visible on the bottom of the flanks, which are entirely absent in the Príncipe White-eye. The white circle around the eye and the white feathers under the wing are thicker in the São Tomé species, which often has a conspicuous yellow forehead and chin. The beak of the São Tomé White-eye is pink or orange-pink, sometimes with a gray spot at the tip of the upper mandible, while the Príncipe White-eye has a gray beak, with pink, if present, mainly restricted to the lower mandible. The Príncipe White-eye occurs mostly within the Obô Natural Park, which has a buffer zone of secondary forest and abandoned plantations, and direct threats to its habitat are currently limited.