BIRD ROCK 185 



At ten o'clock at night I visited tLe west end of 

 tlie Rock to see and hear the Petrels that nest there. 

 The casual visitor to Bird Rock would be quite 

 unaware of the presence of these birds; indeed, one 

 might live there for years Avithout knowing that 

 Petrels made it their home. As far as the Ruck is 

 concerned, the birds are strictly nocturnal ; but as 

 usually only one bird — either male or female — is 

 found on the nest, it is supposed that its mate is at 

 sea feeding. If this supposition be true, I am at a 

 loss to account for the entire absence nf the birds 

 during the daytime. Why should they not return 

 to their nests before nightfall ? And if, as stated, 

 the sea biril takes tlie place of the nest bird, does 

 the latter always feed at night and the former by 

 day, or do they sometimes change about, thus mak- 

 ing the same individual both nocturnal and diurnal 

 in habit ? 



However this may be, I had no sooner reached 

 the part of the Rock tenanted by the Petrels than I 

 was given the most surprising e - idence of their 

 activity during the night. Fi-om the ground at my 

 feet and on every side there issued the uncanny 

 little song — if I may so call it — of birds doubtless 

 sitting at the mouths of their burrows. It was not 

 like the cry of a sea bird, but a distinctly enunciated 

 call of eight notes, possessing a character wholly its 

 own, and not to be compared to the notes of any 

 bird I have ever heard, though at the time it 

 impressed me as having a certain crowing quality. 

 Such a call might be uttered by elves or brownies. 

 Occasionally I saw a blur of wings as a bird passed 

 between me and the lighthouse. 



