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* 
Black-winged Petrel A=1 B=48 C=10 D=133 
( Pterodroma bypoleuca ssp?) A=2 B=6 C=0 D=12 
Birds recorded as P. hypoleuca are probably almost all P. nigripennis 
the Black-winged form. A similar northward movement distribution 
pattern was noted for this species as mentioned for its larger con-gener 
P. externa . Also an increase in number of observations was noticeable from 
September to October. 
White-winged Petrel A=0 B=2 C=13 D=l8 
( Pterodroma leucoptera brevipes ) 
This form has led to much of the confusion in identification of 
small Pterodroma ) and as yet its biology is still obscure. At close 
range most small Pterodroma can be identified readily, but variations in 
this P. leucoptera complex will continue to present problems. More 
concentrated effort is needed on collecting all small Pterodroma . The 
distribution pattern appears to be similar to that of P. hypoleuca 
nigripennis and P. externa but it is displaced 10-12° to the south. 
October observations showed an increase in numbers and a movement north. 
Dark-rumped Petrel A=0 B=0 0=0 D-b 
( Pterodroma phaeopygia ) 
All 4 birds of this species were seen within 400 miles of the main 
Hawaiian chain. This species is possibly overlooked and data are probably 
biased to the low side. 
Bulwer*s Petrel A=23 B=8 C=9 D=7 
(Bulweria bulwerii ) 
Observations indicate a very wide radial distribution from breeding 
areas in the Hawaiian and Phoenix Islands. 
White-throated Storm Petrel A=0 B=0 C=7 D=0 
( Nesofregatta albigularis ) 
All records of this species are within the offshore areas of the 
Phoenix Islands. 
Storm Petrels 
A=1 
C=ll 
D=20 
