234 ORNITHOLOGY OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 



on November llth,* being the last of the summer visitors to arrive. On the 23rd the 

 ice broke up and many birds arrived, including numbers of this species. After this 

 date it was constantly under observation, for several dozens took up their abode in the 

 cliff above the observatory, where, on December llth, the first egg was obtained. 



There was no attempt at nest-making ; the egg was simply laid in a hollow in the 

 earth in narrow clefts and fissures in the face of the cliffs, under boulders, and some- 

 times under stones on the screes sloping from the foot of the precipice, at heights vary- 

 ing from 20 to 300 feet above sea-level. It was often placed far in, and this and the 

 fact that the hole was so narrow made the egg difficult to procure. Some of the eggs 

 were laid at such a distance from the entrance that a spoon had to be lashed to a long 

 bamboo in order to reach them. The searchers could hear the low whistle uttered every 

 few seconds by the sitting bird, but on reaching the spot whence it seemed to proceed 

 the sound would appear to come from an entirely different direction. The dog 

 " Russ " proved to be a great aid in work of this kind, for he easily detected the bird's 

 presence by his keen sense of smell. When caught on the egg the birds brought up a 

 reddish fluid, which issued both from the mouth and nostrils. In addition to the low 

 whistle, these petrels had a harsh screaming chuckle. These noises they kept up almost 

 continuously after dark, especially on still nights. 



They appear to return year after year to the same nesting-places, for both eggs and 

 dead young birds of previous seasons were numerous in the tenanted holes containing 

 the fresh eggs. This fact indicates that a very serious waste of life takes place in some 

 seasons, if not annually. It may be accounted for by the late arrival of the bird at its 

 breeding-stations, which, coupled with the lengthened period of incubation character- 

 istic of all petrels, results in winter setting in ere the eggs are hatched, or the young, 

 which develop slowly, are old enough to leave the nesting-holes. Another, and 

 perhaps more probable, explanation is that the disasters noticed were due to a succes- 

 sion of cold summers, which are actually known to have occurred. None of the eggs in 

 the summer of 1903-4 had been hatched when the Expedition left the islands on 

 February 21st. These facts would seem to indicate that the South Orkneys lie at the 

 extreme limits of possible breeding for Wilson's Petrel. Indeed, for many individuals 

 of this species, perhaps all, during some seasons the climatic conditions place the islands 

 distinctly beyond that range ; though it breeds further south, most likely with similarly 

 disastrous results. 



From 7 to 1 1 p.m. these birds flitted about the cliffs and over the head of Scotia 

 Bay in great abundance, and in striking contrast to their habit in the daytime, when 

 only occasionally was one to be seen on the water, though there were probably many at 

 sea off the islands. 



The nest figured was situated at the bottom of a crack in the rock, about four 



* This and other species appear to be remarkably constant as to the times of their appearance and departure at the 

 South Orkneys. As an instance of this, it is interesting to note that Mr Mossman observed the first Wilson's Petrel 

 in the spring of 1904 on November 12th. 



