Vol 1 ^ in ] Bailey, Notes on Birds of Western Mexico. 379 



to get it, as I found quite often to my sorrow that the Tropic Bird's power- 

 ful, sharp beak would penetrate through my canvas hat, or if the cavity 

 was large enough to permit of it, my heavy canvas jacket. While one of 

 the old birds is always on the nest and gives its shrill scream at the 

 approach of danger, thus making the cavity easily located, the young or 

 egg is not so easily reached as one would think. Only in one case did 

 I find an old bird on its nest where I could photograph it, that case being 

 under a ledge of a cliff and about eighteen inches from the face. The 

 majority were in cavities from two to three feet back, and it takes quite 

 a lot of manoeuvring to get either bird or egg out. The majority of the 

 birds I found were in poor plumage, the constant going in and out of the 

 small nesting cavities having worn the beautiful long tail feathers until 

 some of the ends had broken off, while others captured had none or new 

 ones just growing out. Their flight is not unlike that of the terns, and 

 the rapid wing beat and long tail feathers make this bird readily dis- 

 tinguishable from any other at a great distance. Both birds take turns 

 in incubating and caring for the young, and during this period the bird 

 in the cavity is fed by its mate. The female, and sometimes both birds, 

 is found in the cavity for three or four days before the single egg is 

 deposited. While graceful on the wing this bird is most awkward on its 

 feet, and when alighting to look for a nesting site drags itself along like 

 a bird with both legs broken. The coloring of a series of eggs in my 

 collection varies from a creamy dirty yellow ground color, spotted with 

 a darker yellow, to a dark red ground color, spotted with a darker red. 



Two cases of removing their young happened while I was on White 

 Rock, both of them similar. Two old birds and their single young were 

 found in a cavity, and I took one old bird to skin that night, expecting to 

 get the remaining parent and young the next morning. On returning 

 the next day great was my astonishment to find the two birds gone, 

 and still further was it taxed when I found, after careful search, the two 

 birds in another cavity twenty to thirty feet away. 



9. Sula nebouxii. Blue-footed Booby. — This species I did not 

 find south of Isabella Island, where they were breeding abundantly. Few 

 were seen fishing to the south of the island, and while the largest colony 

 was situated on the beach of the cove on the south side, they invariably 

 passed out of the entrance and, circling the island, did their fishing north- 

 ward. I am inclined to think that these birds never nest near colonies of 

 Sula brewsteri, nor do the two species fish over the same area. I should 

 be glad to get other persons' opinions on this subject. At the time of 

 my departure from Isabella Island, April 12, a number of pairs of Sula 

 brewsteri had arrived and had started to build nests on a small rocky point 

 forming part of one arm of the bay on the south side of the island, but I 

 am inclined to think their arrival here to nest was caused by the treatment 

 they had received on their own nesting grounds — White Rock. The 

 cause of this departure will be explained later on under that species. 



