Black-winged Petrel 
(Pterodroma hypoleuca nigripennis ) 
- 3 - 
This sub-species was observed in numbers with Pterodroma externa on 
December 2 and 3. After that only scattered sightings of individuals 
were observed. Most birds were in fresh plumage and probably preparing 
to migrate south to breed. Of course like all Procellariidae some young, 
non-breeding birds remain on their wintering grounds all year round. 
Bonin Island Petrel 
( Pterodroma hypoleuca ) 
Four birds of the subspecies were observed on December 6 when a large 
storm from the north evidently carried them south of their normal range. 
White-rumped Storm Petrel species 
Storm petrels were observed casually with a high on the fourth of 
December which may have been due to seas and conditions of observation. 
The majority were probably Leach’s but without collecting they could not 
be positively identified. 
Red-tailed Tropicbird 
( Phaethon rubri caud a) 
The reason for so few sightings of this common species appears to 
be the stormy conditions. Red-tails apparently avoid high winds and rough 
seas as much as possible. When leaving stormy areas, Red-tails were 
observed regularly. This phenomenon was noticed on last Decembers 
Northern Grid trip, also. 
White-tailed Tropicbird 
( Phaethon lepturus ) 
White-tails, unlike Red-tails, are often found in rough seas with 
nigh winds. In association with the storm sweeping down from the Hawaiian 
Islands, White-tails were more abundant than last, month, and are 
probably from the main Hawaiian Islands. 
Blue-faced Booby 
(Sula dactylatra) 
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A total of 5 birds is similar to last months and last December T s observations 
on this species. Both adults and immatures were sighted. 
Brown Booby 
( Sula leucogaster ) 
The majority of Brown Boobies were observed close to Oahu on the 17th 
of December. Out of the 10 birds observed, only 2 were over 150 miles 
from land. 
Red-footed Booby 
(Sula sula) 
Seventy-one Red-foots representing all age classes were observed. 
