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14 Brewer's blackbird items out of a total of 106 bird items puts it 

 among the 7 bird species that were represented by more than 5 

 percent. But most of the birds taken by both hawks and owls 

 were common to exceedingly abundant in the area (the Brewer's 

 blackbird was in the latter class). Bond concludes "it is quite clear 

 that none of the species is endangered, or probably appreciably 

 reduced in numbers, by either the hawks or owls." 



Sumner (1928) reports finding a headless young Brewer's blackbird 

 on two different days in a tree cavity occupied by young screech owls 

 (Olus asio) at Claremont, Calif. W. H. Behle (MS.) found remains 

 of this blackbird near the nest of a short-eared owl {Asio jlammeus) 

 in Utah. 



Bond (MS.) writes that he has "seen both Cooper's hawk [Accipiter 

 cooperi] and the pigeon hawk [Falco columbarius] catch a Brewer's 

 blackbird, the former on the ground and the latter in the air." 



In Carmel Valley, Calif., on December 15, 1942, I witnessed the 

 capture of a Brewer's blackbird by a sharp-shinned hawk. A mixed 

 flock of about 500 redwing, tricolored, and Brewer's blackbirds 

 were alternately perching on power wires and flying down in small 

 groups to feed in straw stubble near some horses. The hawk was 

 first noticed pursuing the blackbird, which it seemed to have singled 

 out from a group of about 300 birds flushed from the stubble. The 

 hawk followed the blackbird in a twisting and turning flight; there 

 was a "squawk" from the blackbird as it was caught. The raptor 

 then flew to a nearby thicket, seeming to labor in flight with the 

 blackbird in its claws. The whole chase and capture and removal 

 to the thicket took place not more than 10 to 15 feet above the ground 

 and lasted only a few seconds. 



The usual warning note, tee-uuu, is given when a hawk flies over the 

 colony. It is uttered by other members of the flock when a hawk is 

 pursuing one of them. It may also be used when some large bird is 

 merely passing by, even high overhead. The chorus of schlr-r-r-up, 

 squee and kit-til-tit of the nesting colony suddenly stops as one or two 

 birds utter the warning note and others join in. Looking up one may 

 see a hawk, a crow, a night heron, or even a large gull passing over. 

 When it has gone by the tee-uuu ceases and the chorus recommences. 

 This alarm has been noted on two occasions when airplanes have 

 passed over. On at least four occasions I have heard this note when 

 a duck hawk has soared overhead or flown by; I have also heard it 

 when sharpshins have attacked or have merely flown by and on 

 numerous occasions when crows have flown'past. 



R. M. Bond (MS.) observed the reactions of a flock of Brewer's 

 blackbirds to the attacks of a marsh hawk (Circus cyaneus) as follows: 

 "For about 15 minutes, during an extremely cold spell in February 



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