BULWERIA BULWERII 



MARCH 1964 



APRIL 1964 



'V 



'«» 



Figure 10a. — Distribution of Bulwer's Petrel, March-June 1964. 



Bulwer's Petrel 



Bulweria bulwerii (Jardine and Selby) 



Status : Abundant resident during breeding sea- 

 son, April-September; rare or absent October- 

 March. 



Birds were first seen in March, but in small 

 numbers. Numbers built to a peak in May con- 

 current with the beginning of egg laying along 

 the leeward Hawaiian chain and on islets around 

 the main Hawaiian islands. By September, when 

 most adults and chicks were leaving the breed- 

 ing grounds, pelagic numbers already had drop- 

 ped considerably. After October no birds were 

 seen in the area, with the exception of strag- 

 glers in January and February, until the begin- 

 ning of the breeding season in April when num- 

 bers were large once again. 



Distribution : The density center for Bulwer's 

 Petrel in the study area was within 50 miles of 

 the Hawaiian Islands (figs. 10a, 10b). Greatest 

 numbers were usually seen just south of Lanai. 

 In general the birds favored the western side of 

 the study area. 



22 



