LIFE HISTOEIES OF NOKTH AMERICAN PETRELS AND PELICANS. 209 



called riedra Blanca, but on none of these rocks did they breed. All the birds in 

 this section belonged to the colony breeding on White Rock, and many traversed 

 the sixty miles back and forth daily from tlieir 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 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 

 for the time being, although they still continued to use the rock as a roosting 

 place. It was the guano from this countless flock of birds, which probably had 

 been breeding there for centuries, that the men were engaged in collecting. Dur- 

 ing the day when not fishing they roosted on the sides of the island, and when 

 the men left the top to come down to supper at six, they returned to the top of 

 the ishind to roost and make their so-called nests. Many an evening, as I sat at 

 my skinning table or in front of camp waiting for supper, have I watched these 

 birds as they came in from their day's fishing excursion. From about five o'clock 

 on, as far as the eye could reach, could be seen small flocks of from four to 

 twenty making for the island, and after circling half around it, would generally 

 alight on the top, but a few preferred to roost in the caves in the cliffs of the 

 island. 



Numerous visits to the top of the rock were made at night after specimens, 

 and a series of some seven pairs were procured by walking up to them while 

 asleep and selecting individual birds as I chose. I had seen colonies of birds 

 before, but none like this, and the sight certainly made one take a long breath. 

 The whole island surface was literally covered with birds, some with their 

 heads and necks stretched out along their backs, sound asleep, some picking 

 up bits of bone, long wing feathers, grass, and small chips of stone and guano 

 to form nests with, while others sat on little piles of heaped-up guano with the 

 neck stretched upward watching the approach of a bird about to alight, as if 

 hoping it might be its mate. They always seemed to roost in pairs, each pair 

 always separated, as were also the nests, by enough space to be out of reach 

 of their neighbor's sharp beaks. It was truly a weird sight in the starlight. 

 and the low, hissing sound from the birds that were awake, with the shadowy 

 forms floating through space, reminded one of a graveyard. 



One of the most amusing sights I ever saw was the regular " Mexican cock 

 fight," between males of this species. This combat was, I imagined, over the 

 unmated females, or some single male trying to steal a female from another, 

 and started in this fashion : A male in alighting commenced to strut around, 

 craning his long neck and uttering a low, hissing sound, and on coming near to 

 some mated pair, or some other male also trying this mode of courting, would 

 suddenly stop. Both males now squatted low on their short legs, their breast 

 sometimes touching the ground, while their long necks were craned upward in 

 a double bow. No regular cock fight could be more complete or interesting. 

 While they did not use tlieir feet, their long wings and sharp beaks were thrust 

 out at their rival, and occasionally they met with open beaks, which became 

 locked together in the struggle. Sometimes one would catch the other by the 

 wing, while he retaliated by getting his adversary by the neck, these cases 

 often proving fatal to one or the other of the combatants. Over all this scene 

 was the ever-present smell from the guano, which one must get accustomed to 

 if he would study bird life on an island in the Pacific. Birds with broken 

 wings, as well as those with little strength, were at daybreak quickly put out 

 of the way by the Caracaras, and the gulls made part of their morning meal 

 of these poor unfortunates. 



