60 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



a stop-watch a hunting duck hawk and estimated its speed as between 

 165 and 180 miles an hour. The following observation, recorded by 

 Ralph Lawson (1930), was made by an expert aviator in whom he had 

 great confidence: 



He was flying a small pursuit plane, which had a normal speed of about 125 

 miles per hour and, while cruising about at a considerable altitude, he saw a 

 bunch of ducks flying far below and ahead of him. Thinking to gain some 

 experience in diving at a moving object, he turned the nose of his plane down 

 and opened the throttle of his engine, thereby gaining speed rapidly. While he 

 was still some distance from the ducks he glanced at the wingtip of his plane to 

 see how much vibration his swoop was causing and as he did so, a hawk shot by 

 him "as though the plane was standing still," and struck one of the ducks which 

 fell towards the ground apparently lifeless. At the time the hawk passed the 

 plane the latter was travelling at a speed of nearly 175 miles per hour and my 

 friend thinks that the hawk was stooping two feet to his one but of course that 

 is only an estimate as under the conditions no accurate computation was possible. 

 We do know however that this particular hawk was moving at a rate of speed 

 much greater than 175 miles per hour and perhaps not far from double that rate. 



Mr. Forbush (1927) cites several instances where a duck hawk has 

 attacked and killed larger birds. A red-shouldered hawk was struck 

 and its skull "split wide open"; another was struck and seen to fall. 

 "Audubon tells of a Snowy Owl which snatched a young duck hawk 

 from its rocky perch, but was followed by the avenging parent, which 

 quickly struck the larger bird dead." 



Mr. Forbush also tells of a duck hawk that struck down a large 

 merganser; when the dead merganser was picked up, it was "found 

 that most of its side had been torn out by the force of the blow or the 

 clutch of those powerful claws." He says further: "Swifts are 

 believed to be the swiftest of all birds, and it has been generally 

 asserted that the Duck Hawk is unable to overtake them. I have 

 never found the feathers of a swift near a Duck Hawk's aery, but a 

 farmer in the Connecticut Valle} 7 states that he saw this falcon 

 capture a Chimney Swift. Many swifts, he says, were coursing above 

 the fields, when the falcon made several dashes at them, but missed. 

 At last as one turned to evade the rush, the hawk swung over on its 

 back, and reaching up one foot as it shot by, caught the swift in its 

 powerful grasp." 



Although the duck hawk has been known to kill marsh hawks and 

 sparrow hawks, both of these species have attacked and driven away 

 this powerful falcon. I have seen a colony of common terns drive a 

 duck hawk away from their nesting grounds by attacking him en 

 masse. I once saw one of these falcons perched on a spruce tree, 

 with a flock of Brewer's blackbirds sitting contentedly in the same 

 tree; neither species seemed to be at all concerned about the other. 

 Once a phoebe sat on its nest on a cliff near a falcon's nest that I was 

 examining; I doubt if it was ever disturbed and it probably raised its 



