380 Bailey, Notes on Birds of Western Mexico. [oct k 



All around our camp, which was pitched under the low bushes bordering 

 the little bay, were pairs of boobies, one or the other of the pair covering 

 the eggs while the mate stood close by. This, however, was during the 

 middle of the day, the fishing being mostly done before ten a. m. and after 

 four in the afternoon, during which time one or the other of the birds always 

 remained on the eggs to keep the gulls from stealing them. The poor 

 boobies had a hard time of it here, as the Man-o'-War Birds nested just 

 back of them in the bushes, and lucky was the booby who passed in the 

 entrance of the bay without having to disgorge part, or maybe the whole, 

 of its day's catch to this robber. Numbers of nests were on the sandy 

 beach just above high tide, while others were still further back under the 

 shrubbery and below the Man-o'-War Birds, and still another colony was 

 situated on the top of the rocky southwestern side of the island. All 

 the birds were very tame, and I think had not been molested since the 

 expedition of the Biological Survey in 1897, as Mr. Beermaker on landing 

 in search of guano deposits in March, 1904, had not found them breeding 

 at that time, nor had he disturbed them in any way. When I first started 

 in to get a series of eggs, I used my foot to remove the booby from them, 

 but after the first few attempts I found that the sharp beak whenever 

 it came in contact with my leg drew blood, and almost penetrated through 

 my cowhide boots, so I soon abandoned this method. Two eggs were 

 generally the complete set and but three sets of three were discovered 

 while on the island, and in some cases highly incubated single eggs were 

 found. In case of the latter I am inclined to think the gulls had stolen 

 one of the eggs after incubation had commenced. No nest was made, 

 a slight hollow being scratched in the sand or earth, while those on the 

 rocky side of the island simply deposited them on the bare rock or on the 

 little drifted earth that happened to be on its surface. During the moon- 

 light nights these boobies could be seen going and coming, and I have no 

 doubt their best catches were made at this time, as they were then unmo- 

 lested by the Man-o'-War Birds. Single fresh eggs gathered by the crew 

 were made into omelets, but the flavor was rather rank. 



10. Sula brewsteri. Brewster's Booby. — This species was com- 

 mon along the coast at San Bias, roosting on the small rocks near the 

 shore and on a large white rock some ten miles west of San Bias, called 

 Piedra Blanca, but on none of these rocks did they breed. All the birds 

 in this section belonged to the colony breeding on W! ite Rock, and many 

 traversed the sixty miles back and forth daily from their nesting and 

 roosting place on the Rock to their feeding grounds near the coast. Never 

 did I see a Blue-footed Booby in this section; hence my assertion that the 

 Brewster's Boobies went east and south from their colony to fish, while 

 the Blue-footed Boobies went northward. Thousands of these boobies 

 were roosting on White Rock and some few had been laying previous 

 to our arrival, but as the workmen had robbed the nests as fast as eggs 

 had been deposited, the birds had become disgusted and stopped laying 



