LIFE HISTORIES OF NORTH AMERICAN PETRELS AND PELICANS, 177 



its egg. There was not a sound save our own voices, yet there must have 

 been thousands of birds within earshot. Each was intent upon its task of 

 incubation, now very near completion, for most of the eggs we examined w^ere 

 already chipping, and in three burrows we discovered a tiny, fluffy, grey chick. 

 When l^rought out to the light the petrel, which is about 8 inches long, seemed 

 very stupid, and scrambled away on being released. On the wing, however, 

 it is the perfection of ease and grace. All the writers of the sea have made 

 mention of storm petrels. 



As it was now far past sunset and the Christmas moon was shining brightly, 

 we decided to await the arrival of the other batch of birds — the mates of those 

 sitting quietly in the burrows. Very little has been written about this species 

 of storm petrel, so it was with eager interest that we awaited the progress of 

 events. We marked 10 birds in the burrows, to see if this could give any clue 

 to their habits. The same musty smell that pervades the mutton-bird rook- 

 ery, arising from the natural oil with which the birds' plumage is greased, 

 was noticed here, and it soon permeated our blankets and clothes. It was 

 at 9.30 p. m. that the first storm petrel came in from sea and circled swiftly 

 and silently close to the ground, as if searching for its own particular burrow. 

 What a problem, especially if the night be dark, to find one's own home amid 

 such tens of thousands of a similar nature. Bird followed bird every few 

 minutes in silence, until about 10.30 the numbers had increased so that two 

 or three could be seen at once. But where were the numbers scuttling about 

 the ground and cutting the air in all directions amid noisy arguments and 

 welcomes? Two hours later, still no great increase — one* and twos still passed 

 our vantage point, flashing their white under surfaces as they occasionally 

 turned in the moonlight, but none settling within sight, though the night was 

 clear and bright. Not a sound until we beat or stamped upon the ground, 

 when an impatient or hungry bird nearby would call from a burrow with a 

 low, rasping voice as untuneful as all sea birds' notes are. 



We estimated that at the very least there must be 50,000 nesting burrows in 

 the sand rises about us, and we were forced to the conclusion that all the 

 birds can net return every night. It appears as if some only, and that a very 

 small proportion, return to change places with the brooding mate. Search as 

 we would in the small hours of that moonlit morning, we could only find one 

 burrow where two birds were at home. We then snatched an hour's sleep 

 under the friendly shelter of a saltbush. and about 3.30 a. m. were awakened by 

 two storm petrels, with low cries, running onto us from behind and taking 

 wing. This illustrates the habit petrels have of running onto a mound, or 

 throwing themselves from a cliff, before taking flight. Their long wings pre- 

 vent them rising easily from flat ground. By daylight not a bird was to be 

 seen. We visited our marked burrows soon afterwards, and oft^^i birds which 

 were each labeled with a small piece of twine seven were still at home, two had 

 changed shifts, and one burrow was empty. This corroborated somewhat our 

 opinion that a small proportion only of the birds belonging to the rookery 

 come in each night. The sitting bird must therefore be four or five days with- 

 out food. We felt we had only touched the fringe of these interesting ques- 

 tions and that a longer stay on the island was necessary for their solution. 

 But we had not the time to spare ; we must be off. 



Further visits to the .petrelry were undertaken on the 16th and 17th February, 

 and again on the 23d and 24th February, 1907, to extend and make more com- 

 plete our observations on the breeding habits of " Mother Gary's chickens." 



Wading across the lagoon the southern rookery was reached, and examina- 

 tions of the white-faced storm-petrel's burrows revealed young birds in .several 

 stages of development. They were tiny fat little balls of slaty-grey down 



