The Blue-footed Booby has captivated the human imagination for centuries with its mating display, in which its vivid baby-blue feet play a key role. The other part of the name—booby—is reportedly taken from the Spanish for “stupid,” (“bobo”) and refers to these birds’ tameness around people. Like its North Atlantic relative the Northern Gannet, Blue-footed Boobies catch fish in spectacular dives from high in the air. Watching large flocks pursue shoaling fish can be breathtaking, with hundreds plunging into the ocean at any moment.
Cool Facts
To stay cool in very hot environments, Blue-footed Boobies sometimes defecate on their feet (a behavior called urohydrosis). They also flutter the skin of their throats (the gular pouch) by rapidly vibrating bones in their throat, which creates evaporative cooling through the open mouth.
The blue color of Blue-footed Booby’s feet varies in its intensity. Boobies with bluer feet appear to have more success in finding a mate than birds with duller blue feet. One study looked at foot color in relation to the health of young chicks and found that healthiest chicks tended to have fathers with intensely blue feet—possibly an indication of the father’s ability to keep himself well fed. Although the famous mating display might seem comical to humans, the display of foot color provides critical information on a bird’s health and ability to provide for young.
The Blue-footed Booby makes no nest, but lays its eggs on bare ground. The incubating birds defecate while on the nest, and the eggs become surrounded by a circular wall of excrement.
