BLUE-FOOTED BOOBY 



tail white. Iris gray; bill black; bare skin 

 of face pink; legs and feet red or dark pink. * 



Young. Sooty brown above and below, paler 

 on breast and abdomen, the plumage becoming 

 more exclusively white as the adult plumage 

 is approached. Bare skin surrounding eye lead 

 gray. This booby is notable for its many 

 phases of coloration, ranging from sooty or dark 

 grayish brown, through intermediate stages in 

 which the rump, tail and portions of the under 

 parts are white, to the white plumage with 

 grayish brown outer wing quills of the adult. 

 The changes in the plumage are not fully under- 

 stood; individuals still in partly grayish brown 

 plumage are known to breed. 



This species occurs on both sides of the Isth- 

 mus and is often to be seen on the Caribbean 

 not far from Colon, and about the Pearl Islands 

 on the Pacific side. Their flight is powerful and 

 graceful, suggesting, as one writer has said, that 

 of a large shearwater, being interrupted by 

 periods of gliding, the flocks maintaining perfect 

 formation and acting in perfect unison. It is the 

 only booby that nests in trees or bushes. 



3. Sula nebouxii Milne-Edwards 

 Blue-footed Booby 



Sexes alike. Length about 867 mm. (34.00 



in.); tail 215 mm. (8.50 in.). Head, upper part 



and sides of neck smoky grayish streaked with 



white ; front of forehead and throat nearly white, 



in 



