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evolved social signals facilitating flocking behavior in flock feeding 
birds. The pronounced arcing of feeding Pterodroma flocks creates a 
signal that can be seen for a great distance. I further suggest that 
dark phase populations (Wedge-tails being case in point) arise as a 
result of relaxed selection pressure on flocking behavior. This could 
occur* for instance, in regions where food sources are non-contageously, 
i«e« evenly, distributed. This tenuous hypothesis is assuredly not a 
complete answer,but none the less it should be considered, in any 
investigation of the subject. 
Sooty Shearwater A~6 B=0 036 D*35 
(Puffinus griseus ) 
Struggling migrants were observed throughout September and increased 
to two poorly defined peaks in the first and third weeks of October. In 
contrast to most years. Sooty Shearwaters moved through our areaafter 
the bulk of Slender-billed Shearwaters. Little difficulty was encountered 
in separating this species from the next, provided distances were not 
great and light was favorable. Birds were heading generally south, but 
directions were not as strictly adhered to as the Slender-billed Shearwater. 
Birds were seen as single birds and pairs and did not associate with Slender- 
billed flocks. 
Slender-billed Shearwater A“3 B«0 Oh.2 D*l5 
( Puffinus tenuirostris ) 
The bulk of this migration occurred in the grid area. The relatively 
few non-grid observations represent the beginning, end, and edges of the 
main stream of birds. The low numbers further illustrate the channeled 
direct flight of this species. 
Christmas Island Shearwater A*0 B a 0 C*3> D=1 
(Puffinus nativitatis ) 
Five of the birds recorded were in proximity to the Phoenix Islands. 
One bird was seen in She > N area. 
Newell 1 s Shearwater A=13 B*0 C-0 D 38 !! 
( Puffinus puffinus ) 
All records for this species were within 1|00 miles of the main 
Hawaiian chain. 
Audubon’s Shearwater A=0 B*0 C=10 D*0 
( Puffinus lherminieri ) 
All observations are from island populations in the Phoenix area. 
Birds were noted in feeding flocks. This species seems to show a strong 
aversion to ships as numbers observed at-sea seem incongruous with the island 
