NO. 2298. THE GUANO BIRDS OF PERU—COKER. 471 



Raimondi's observations of the nesting places of S. variegata 

 (quoted on p . 508, below) agree essentially with mine. 



SULA NEBOUXI MHne-Edwards. 



THE PIQUERO MAYOR (GREATER PIQUERO). 



The larger Sula, the blue-footed booby, gray gannet, or "piquero," 

 was not observed south of Guanape Islands (8° 35' S.), and it was, 

 therefore, a surprise to me afterwards to learn that the range of the 

 species is given as from the Gulf of California to Chile. The original 

 specimen described by Milne-Edwards ^ was assumed to have come 

 from Chile, but it is not clear upon what evidence the southern records 

 are made. 



In color and habit the blue-footed booby is in striking contrast to 

 the smaller white-head species, except in the manner of feeding and 

 in this there are noteworthy differences. The showy white markings 

 of the variegata are wanting, the plumage of all upper parts being 

 variegated, and the eyes are yellow instead of ruby (pL 60). In 

 breeding habit the nests are widely scattered on the level ground 

 or gentle slopes. In feeding, the nebouxi was often observed to use 

 localities which the variegata did not frequent. At the Lobos de 

 Tierra islands the gannets of the larger species were almost constantly 

 feeding in the very shallow water near the gentle beach in front of 

 our camp. The white-head gannets frequently passed over this place 

 but never plunged into the shallow water. I never observed them 

 feeding except in the deeper waters and generally plunging from 

 some height. 



The gray gannets would circle about over the bay, often with the 

 bill pointing directly down, as they searched the water for their prey. 

 If a little off-shore they might plunge from some height, but, in the 

 shallow water two or three feet in depth near the beach, the drop 

 was made from only a few feet above the surface or else the bird 

 dived at an angle when flying barely above the water. Between 

 times they were resting with the pelicans on the low rocks near-by. 



When this piquero plunges, the wings are held out angularly, and 

 just as the bird is about to enter the water the wings are folded to the 

 body. The bird emerges very promptly and may rest a few moments 

 on the surface or at once arise in flight. Sometimes it seemed to 

 find itself too high for the contemplated drop, when it would descend 

 by a spiral course of flight to a proper level for the plunge. I observed 

 a gannet dive vertically from the air into the water that was only 

 about 6 inches in depth, while another more prudent bird dropped 

 to its feet in the water at nearly the same place and then secured his 

 prey. It is interesting to note how frequently the piqueros of this 



1 Milne-Edwards, A. Recherches sur la fatine des Regiones Australes. Annales des Sciences naturelles 

 Zoologie, ser. 6, vol. 13, art. 4, pp. 36,37. Paris, 1882. [See p. 37 and pi. 14.] 



