EASTERN PIGEON HAWK 79 



gull continuing its flight unimpeded— the falcon let go, and rising 

 almost directly up for 30 or 40 yards made off." Harold H. Bailey 

 (1906) saw one chasing a red-billed tropicbird on the west coast of 

 Mexico; he also saw it put to flight gulls and caracaras that were 

 feeding on carcasses. William G. Fargo writes to me that on a long, 

 narrow lake in Florida he saw a number of kingfishers strung along 

 at intervals, and practically every one of them was attended by a 

 pigeon hawk, sitting some 10 or 20 yards away; and when the king- 

 fisher moved the hawk wont along too. Mr. Brewster (1925) wit- 

 nessed the following peculiar behavior of a pigeon hawk: 



He was either playing or fighting with a Crow, the former I thought, for although 

 the behaviour of both birds was rough and aggressive, it seemed to represent 

 mutual participation in a sportive game curiously regulated and much enjoyed. 

 Thus the successive lungings and chasings were not either one-sided or haphazard, 

 but so conducted that each bird alternately took the part of pursuer and pursued, 

 and when enacting the latter role gave way at once, or after the merest pretence 

 of resistance, to flee as if for its life, dodging and twisting; yet it was prompt 

 enough to rejoin the other bird at the end of such a bout, when the two would 

 rest awhile on the same stub, perching only a few feet apart and facing one another, 

 perhaps not without some mutual distrust. During these aerial evolutions the 

 Hawk screamed and the Crow uttered a rolling croak, almost incessantly. They 

 separated and flew off in different directions when my presence was finally dis- 

 covered. 



James S. Hine (1919) picked up, in Alaska, "a pigeon hawk that 

 had been in an encounter with magpies. The hawk received such 

 severe treatment that it was unable to fly away and it allowed me to 

 walk up to it. The single magpie which was engaging the hawk 

 when I first realized that a fight was on flew gracefully away on my 

 approach to join six others of its kind which, very likely, had been 

 helping in a common attack upon their enemy." 



Voice. — The cackling notes heard near the nest reminded me, in 

 form at least, of the protesting notes of the sharp-shinned hawk, 

 though they were louder and harsher. Dr. Townsend (1920), who 

 was with me, recorded the cry as "a rapidly repeated wheet, wheet, 

 wheel varied to a ki, ki, ki, harsher in the female than in the male." 

 Ora W. Knight (1908) records the same notes as "an angry cac, cac, 

 cac, cac, cac varied by a shrill piercing ki-e-e-e-e-e." Mr. Brewster 

 (1925) heard one "uttering, while still on the wing, a rapidly delivered 

 kla, kla, kla, kla, kla, kla almost precisely like the familiar outcry of 

 the sparrow hawk." 



Field marks. — The falcon form and manner of flight are character- 

 istic. It could hardly be confused with the larger falcons, but it 

 might easily be mistaken for a sparrow hawk, unless the colors could 

 be seen plainly; the brilliant colors and the conspicuous markings of 

 the sparrow hawk are very distinctive with any reasonable amount 

 of light; in the pigeon hawk the slaty-blue back of the adult male and 

 the dark brown back of the female and young bird are distinguishable 



