Magpies and Ferruginous Rough-Leg Feeding Together
Magpies and Ferruginous Rough-leg Feeding Together
In the Condor for July-August, 1933, Joseph Dixon reports three Magpies (Pica pica hudsonia) robbing a Golden Eagle of its prey. Apparently there may be association of a sort among birds of similar feeding habits.
On December 4, 1932, I was driving through southern Wyoming, and a few miles south of Tulsa I noticed a cluster of birds on the highway some distance ahead of the car, apparently feeding on the carcass of one of the numerous jackrabbits run over by cars. As I approached slowly I could see that three or four Magpies and a Ferruginous Rough-leg (Buteo regalis) were all practically “rubbing shoulders” as they busily tore at the jackrabbit remains. The Magpies were the first to leave at my approach, and the hawk flapped away reluctantly, to perch on a fence post until I should leave.
Curiously enough, on October 27, 1933, I was driving over that part of the road again and in almost the identical spot another jackrabbit had been run over and a group of birds was clustered about it, this time several Magpies in company with a crow (presumably Corvus brachyrhymhos hesperis). On returning over this road three days later, I found these birds still in that vicinity.
Ball and Court (Auk, 48, 1933, p. 604) in Maryland, observed a Magpie in company with some crows, being pursued by a kingbird. Hess (Auk, 31, 1914, p. 402) observed a Magpie in Illinois being “harassed by a half-dozen crows in a hedge.” Cameron (Auk, 31, 1914, pp. 159-167), in his study of the Ferruginous Rough-leg, found remains of young Magpies at the nest, and alsa saw three Magpies alight near the hawk nest. Again, Munro (Condor, 31, 1929, p. 113) flushed a Goshawk from the “still warm body of a Magpie.” Taverner (Auk, 36, 1919, p. 252) noted, in Alberta, that Magpie nest’s were invariably found not far from the nests of Red-tails or Swainson Hawku and wonders, if the proximity were not accidental, which species first chose the locality.
Apparently relationships among birds of prey, and between them and other speoies, vary with circumstances. I have known an Emperor Goose to hatch out its eggs in close proximity to the nest of a Snowy Owl. On the other hand, aU least two Short-eared Owls, themselves raptors, in the same district fell prey to Snowy Owls.
Thus we see that at one time the Magpie is “harassed” by crows, and again the Magpies fraternize with crows amicably. We learn that young Magpies are the prey of a Rough-legged Hawk. On the other hand, a group of Magpies is found amicably feasting on carrion in company with a Rough-leg, when this hawk could easily have reached out and seized one of the birds. Which arrived at the carcass first, hawk or Magpie?
It is dangerous to speculate on mental traits of birds, but the subject is worth careful study, and more extensive observations by ornithologists may eventually throw some light on the influences affecting some of these relationships.
Olaus J. Murie
Bureau of Biological Survey, Jackson, Wyoming, December 29, 1933
