LIFE HISTORIES OF ISTOETH AMERICAN PETRELS AND PELICANS. 167 



and sometimes nuder stones on the screes sloping from the foot of the 

 precipice. 



The birds resort in thousands to the clifFs of Laurie Island, one 

 of the South Orkney Ishmds, and nest all the way from 20 to 300 

 feet above the sea. Kobert Hall (1900) thus describes the nesting 

 of this species at Kerguelen Island : 



The yellow-webbed Wilson petrel is a delicate creature that goes straight 

 to sea iu the early morning, and comes back to the rocks in the gloaming. 

 Most of my time was spent among the stones below 1,000 feet, where this 

 petrel is to be found in great numbers by diligent search. At 1,500 feet 

 (Thumb Peak) one flew from the boulders in the daytime, which showed that 

 a nest was there. Having returned from the sea into the harbours at dusk 

 (8 p. m.) Wilson's petrel is then to be seen, flying to and fro before a ridge 

 of rough-looking rocks. At 6 p. m. I observed (February 2) a gathering of 

 from 50 to 60 bii"ds off the South Head of Greenland Harbour. Generally 

 they are unassociated until they come in toward night. They are seldom to be 

 seen on land in the daytime, and I only noticed a bird flying up and down a 

 part of a valley of stones, more than a mile from the sea, and a creek, which 

 led from this highland, had encouraged the bird to go there. It reminded me 

 of a martin collecting insects. Having sat down to finish a piece of buttered 

 rye bread, I observed the bird alight on a jutting mass of loose stones, and 

 this led me to remove the stones from the entrance to the nest and to discover 

 a delicate egg. 



At about 8 p. m. the croaking begins, for now the " night shift " has come 

 in from the sea to go on duty. Many congratulations seem to be exchanged. 

 Go straight to a wild-looking piece of the coast if you want nests. Look under 

 large or small slabs of stone or within the crevices in the cliff-sides. Most of 

 the nests are saucerlike and neatly put together with loose twigs. Your shovel 

 will act as a lever to lift the slabs and expose them, when the sitting bird 

 will move away to the farthest corner to escape the light, never offering to 

 bite, although the act would be harmless. At 7 a. m. I have found the male 

 bird sitting on the egg, indicating in this case, that it will sit out the day. 

 A male also flew on board on one occasion during the night, which probably 

 meant that it had a mate sitting on the nest. Thus the male possibly sits 

 either day or night. At 8 p. m. I have taken both male and female from a nest 

 which was on an earthen bank and had an entrance and an exit. 



The nests of this species were built principally of azorella stalks. They were 

 flat, in a shallow indentation beneath a stone, and had no definite tunnel run- 

 ning to them. The bird would sometimes scratch an entrance. A typical nest 

 measured 7 by 5 inches, and the depth of the bowl was 5 inches. On handling 

 a bird, it will (like other petrels) eject a fatty globule for a distance of 2 

 feet. I used to track the sitting birds between 8 and 10 p. m. by their strong 

 but mellow note. One evening's search produced seven nests containing young 

 and eggs. The eggs differ very slightly in size : Six measured 1.3 inches by 

 0.9 inch. On February 3d I found three eggs (fresh and hard set) ; on 7th, 

 8th, and 9th, four fresh eggs, seven young nestlings and two hard set eggs; 

 on the 14th one hard set egg. The parents sit with the young during the 

 night. 



Dr. E. A. Wilson (1907) on January 9, 1902, at Cape Adare, South 

 Victoria Land, found a still more elaborate nest. He says : 



Two of these crevices could not be reached, but soon we saw a bird hover 

 round ftnd settle upon a large boulder. Hunting about for a burrow underneath 



