The Coues Petrel 



Taken on the Southeast Farallon 



All Petrel bur- 

 rows have a pecu- 

 liar musky odor, 

 and this character- 

 istic odor inheres in 

 the bird itself, inso- 

 much that a trained 

 nostril can detect 

 the presence or ab- 

 sence of Petrels 

 by sniffing at 

 the crevices. 

 When dis- 

 turbed or 

 captured , 

 the bird im- 

 mediately 

 ejects a 

 strong- 

 smelling oil 

 from which 

 its own sen- 

 teitr propre 



undoubtedly proceeds. This oil is derived from the tiny squids and 

 crustaceans — chiefly the nauplius form of the rock lobster, it is said 

 — which constitute the Petrel's staple food, and represents merely a 

 normal product of digestion. This chyme is discharged copiously, 

 sometimes to a distance of two or three feet, and it is probably offered as a 

 ransom rather than as a repellant. Its forcible discharge involves the 

 bird's nostrils and is attended by considerable discomfort, as subsequent 

 sneezings and efforts to clear the nasal passages show. The young are 

 fed by regurgitation with this same most assimilable oil; and it is this, in 

 all probability, which the male offers to his mate after the lengthy quest 

 a-sea. 



The egg of the Coues' Petrel, pure white or with a faint wreath of 

 cinnamon about the larger end, is large for the size of the bird, as is the 

 case with most monotokous species. It is about the size of that of the 

 Storm Petrel (Procellaria pelagica), decidedly smaller and perhaps a little 

 more rounded than that of the Beal Petrel. Its deposition occurs about 

 the 1st of June, varying somewhat with the season, and the bird is occu- 

 pied with its care and that of the young for fully two months. 



While the interstices of stone walls are undoubtedlv the favorite 



Photo by the Author 



NESTING GROUND OF THE COUES PETREL 



2026 



