DECEMBER 19S4 



JANUARY 1965 



»•* 





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• 1 bird 



• 5 birds 



• 25 birds 

 •lOO birds 





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Bonin Petrels were recorded from October 

 through January and in April and May. No 

 more than three were seen in any month. No 

 attempt was made to separate this form from 

 the abundant Black-winged Petrel until October 

 1964, and most identifications thereafter were 

 only tentative. 



The number of sightings was too small to 

 allow an analysis of distribution, although the 

 months in which the species was seen are those 

 in which large numbers were on their breeding 

 grounds in the leeward Hawaiian chain. 



Most sightings were in the northwestern cor- 

 ner of the study area, although one tentative 

 identification was made at lat. 14° N., long. 148° 

 W. POBSP personnel collected a specimen at a 

 comparable latitude (15° N.) west of the study 

 area. 



In view of the abundance of Bonin Petrels 

 along the leeward Hawaiian chain just a few 

 hundred miles west of the study area, it is sur- 

 prising that very few individuals were seen. So 

 little is known about the pelagic habitat require- 

 ments of this bird that theories about its dis- 

 tribution are speculative at best. Its pelagic 

 range during the breeding season seems re- 

 stricted to waters fairly close to its breeding 

 grounds; its nonbreeding range is unknown. 

 The low numbers suggest that it was merely a 

 straggler. 



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