Avise's Birds of the World

Blue-footed Booby
Sula nebouxii

Native Range: Pacific Ocean

Notes: little sexual dimorphism, except that the male is slightly smaller, has more yellow in the iris of the eye and paler feet; the bright blue feet are used in courtship displays on the colonial nesting grounds of isolated islands; these birds have permanently closed nostrils made for diving, and breathe instead through the corners of their mouths.