Attributes / relations provided by
♦ 1del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.).
Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
♦ 2Why do Gull-billed Terns Gelochelidon nilotica feed on fiddler crabs Uca tangeri in Guinea-Bissau?, Eric W.M. Stienen, Allix Brenninkmeijer & Marcel Klaassen, ARDEA 96(2), 2008, p. 243-250