Blue-footed boobies have bright blue feet due to their diet, and the level of brightness shows how healthy the bird is to their mate! : r/Awwducational
Dancing Blue-Footed Boobies - NWF | Ranger Rick
Blue footed booby baby Banque de photographies et d'images à haute résolution - Alamy
Blue-Footed Booby - Go Galapagos
Blue-Footed Booby Fact & Information Guide - American Oceans