396 PETRELS AND SHEARWATERS 



M. Barrington's statement in support of this, that during these hours 

 of seclusion they keep up a constant " churr" quite audible over one 

 hundred yards. Mr. W. Eagle- Clarke l affords us yet further light 

 on the life-history of these birds. Writing of the storm-petrel in the 

 Flannan Islands, he says that " they fly noisily about the islands during 

 the night-time," and goes on to remark that they " are entirely absent 

 during the day-time, leaving even small ohicks to take care of them- 

 selves, and do not return till darkness sets in, when they tend their 

 young and depart again early in the morning, probably to spend the 

 day far out at sea in search of food. We opened out a number of 

 their nesting-holes at all hours of the day, but the old birds were 

 always absent, except in one instance, where the young had only 

 recently emerged from the egg." Thus it is implied in this account 

 that the burrows are occupied by day only while the birds are incu- 

 bating. And this interpretation Mr. Eagle Clarke confirms in response 

 to a letter I addressed to him on the subject while these pages were 

 in the press. So soon as the young are hatched these birds spend the 

 day far out at sea resting, and perhaps at intervals feeding. At dusk 

 all come landwards, the females to brood, the males to disport them- 

 selves and feed anew. Perchance they too take a spell in the nursery, 

 releasing the female. 



According to Seebohm, Leach's-petrel in St. Kilda breeds in small 

 subterranean colonies, a number of nesting cubicles opening out into a 

 common tunnel. Similarly, it should be noted that the late Dr. E. A. 

 Wilson (op. cit.) found more than one pair of Wilson's-petrel breeding 

 in the same burrow. Moreover, the exceptional severity of the climate 

 in the Antarctic area of its breeding range entails a high death-rate 

 among the young, and during unusually cold summers none may be 

 reared at all. In one case he took from a burrow an adult male and 

 female, then two eggs, one clean and newly laid, the other old and 

 rotten, and under all another dead and flattened adult. As the work 

 of digging out the burrow was going on, a fourth bird was hovering 



1 Annals Scot. Nat. Hist., 1905, p. 85. 



