LIFE HISTORIES OF NORTH AMERICAN PETRELS AND PELICANS. 201 



occasional visitor on our coasts, though its breeds abundantly at 

 various localities in the AVest Indies. 



Nesting. — According to Audubon (1840) it formerly bred on one 

 of the Dry Tortugas; I quote from his account of this colony as 

 follows : 



About eight miles to the northeast of the Tortugas Lighthouse lies a small 

 sand bar a few acres in extent, called Booby Island on account of the number 

 of birds of this species that resort to it during the breeding aeason, and to it 

 we accordingly went. We found it not more than a few feet above the sur- 

 face of the water, but covered with boobies, which lay basking in the sunshine 

 and pluming themselves. Our attempt to land on the island before the birds 

 should fly off proved futile, for before we were within fifty yard.s of it they 

 had all betaken thems'elves to flight, and were dispersing in various directions. 



The nest of the booby is placed on the top of a bush, at a height of from 

 four to ten feet. It is large and flat, formed of a few dry sticks, covered and 

 matted, with sea weeds in great quantity. I have no doubt that they return 

 to the same nest many years in succession and repair it as occasion requires. 

 In all the nests which I examined only one egg was found, and as most of the 

 birds were sitting and some of the eggs had the chick nearly ready for exclu- 

 sion it is probable that these birds raise only a single young one, like the com- 

 mon gannet or solan goose. 



This account of Audubon's has been discredited by some modern 

 writers, who think he must have been mistaken as to the owners of 

 the nests, because this species is known to nest only on the ground 

 and to lay two eggs instead of one. But, as Audubon studied the 

 birds at close range and shot some 30 specimens, which he described 

 and figured accurately, I see no reason for doubting his statement; 

 moreover, Baird, Brewer, and Ridgway (1884) write that " Peale 

 found it breeding on nearly all the coral islands visited " by the 

 Wilkes exploring expedition, and that " the nests were constructed 

 of sticks and weeds on bushes and low trees, and were generally 

 found to contain but one e,ggy 



The best modern account of the habits of the booby on its breeding 

 grounds is by Dr. Frank M. Chapman (1908«). His studies were 

 made on Cay Verde in the Bahamas, which he describes as follows: 



Cay Verde lies on the eastern edge of the Columbus Bank, 30 miles southeast 

 of Little Ragged Island. It is about 0.5 mile long by 0.25 mile in greatest 

 width, the longer axis lying approximately north and south, and, roughly esti- 

 mated, contains some 40 acres. On the west and south, or shallow, bank sides 

 there are steeply shelving beaches, where under favorable conditions a landing 

 may be easily made. On the eastern side the deep blue waters of the ocean 

 break directly against the characteristic water-worn limestone rock, of which 

 Cay Verde, in common with other Bahama Islands, is composed. At the 

 northern end, where the islet terminates in a point, this i-ock is but little above 

 sea level. Southward it gradually increases in height and, with pronounced 

 irregularities in coast line, reaches a blufflike elevation of 75 feet at the 

 southeastern extrennty of the islet. 



About one-eighth of the surface of the Island is covered with a dense growth, 

 chiefly of sea grape {Cocrolohis tivifera), but with a liberal mixture, mainly 



