378 Bailey, Notes on Birds of Western Mexico. [octf 



6. Sterna fuliginosa crissalis. Pacific Sooty Tern. — I had been 

 told by both the captain of my boat and Mr. Geo. Beermaker, that 

 on the northern grassy slope of Isabella Island I would find thousands of 

 a small white gull breeding, but on going over the ridge I found to my 

 sorrow that they had bred and gone. Everywhere scattered amongst 

 the tall rank grass could be seen the well worn nests of the season, and 

 so thick were they that we could hardly step without treading on a nest. 

 But what puzzled me most was the number of skeletons of dead birds 

 scattered everywhere about. The skeletons were almost complete, with 

 the long wing feathers, tail and head feathers still in place, so I presume 

 that either the gulls or crabs and lizards had eaten everything clean. If 

 these were old birds, and the remains proved clearly that they were, what 

 could have killed them? and what had become of the eggs? as I was unable 

 to find a single nest with even spoiled eggs in it. I should estimate that 

 at least five hundred dead birds were seen, and the cause of their death 

 will have to be explained by some one arriving in time for, and staying 

 through, the breeding season. Mr. Beermaker informed me that when 

 visiting the island the previous year, the last of March, these birds were 

 just laying, but as I paid my visit to their nesting site on April 8, they 

 must breed earlier some seasons than others. A single skeleton was saved 

 and is now in my collection. Large flocks of these terns were seen off Isa- 

 bella Island, following schools of small fish, and a few roosted on the rocky 

 face of the southeastern end of the island during the daytime. 



The cries of this bird, with the squak of the boobies, were most notice- 

 able after dark, and as they could be seen and heard going and coming at 

 all times' of night, they probably gather as much food by night as by 

 day. 



7. Puffinus cuneatus. Wedge-tailed Shearwater. — A number 

 of birds which I took to be of this species were seen between Cape St. Lucas 

 and Mazatlan, but none were taken, neither were they seen near the coast 

 of San Bias nor around the islands, excepting Isabella. 



8. Oceanodroma melania. Black Petrel. — This species was very 

 common between the mainland and islands, and from what I learned they 

 must have bred on the lower end of Cleofa Island, and on White Rock 

 later in the season, although no eggs were taken during my stay at the 

 latter place. 



9. Phaethon sethereus. Red-billed Tropic Bird. — This beauti- 

 ful bird I first found breeding on White Rock, and during my stay of three 

 weeks, a number of cavities containing their nearly fully fledged young 

 were discovered, and also fresh eggs. On Isabella Island, April 8 to 12, 

 nearly full grown young and a number of fresh eggs were also found, so I 

 imagine they have two settings. In every case an old bird was found in 

 the cavity with young or eggs, and from a broken and sucked egg I found 

 in one, I am inclined to think that the Western or Heermann's Gulls even 

 entered here for food. If such is the case I know they had a hard time 



