Interspecific Relations Between Goshawks and Ravens
Interspecific Relathns between Gosbawks and Ravens.-On October 6 and 7, 1955, in the Copper River region of south-central Alaska, four encounters between Goshawks (Accipiter gentiZis) and Ravens (Corous corax) were witnessed. During the late morning of October 6 at Mile 158 on the Richardson Highway, a Raven and an immature Goshawk were seen circling in close proximity 40 feet’ overhead. Intermittently, one of the birds would dip slightly toward the other, which would then exhibit a mild avoidance reaction and return the action. Overt aggressiveness or active chasing were not witnessed on the part of either bird and there was no vocalization. Approximately five minutes elapsed before the birds parted, soaring from view over the trees. Later the same morning at Mile 151 a Raven flew low over the highway with an adult Goshawk following a few feet behind and to the side. Neither bird was flying rapidly, but both veered sharply and returned over the timber when the observers came into view below.
On Gctober 7, two additional encounters were seen, the first during the early morning at Mile 141 on the Richardson Highway. On this occasion the birds appeared quite suddenly, flying rapidly 15 feet over the trees with an adult Goshawk in definite pursuit of the Raven. After a chase of approximately 50 yards, the hawk closed the short gap and the Raven turned, beating its wings, and uttered a series of loud guttural notes. The Goshawk turned sharply, and both birds flew from view in opposite directions. During the early afternoon at Mile 119 on the same highway, an adult Goshawk flew low over the road followed closely by a Raven. Both birds promptly disappeared among the trees.
These two large diurnal birds, one a raptor and the other at least partly so, are widespread and abundant in this region. Opportunities for contact between the two species would seem numerous and it is reasonable to assume that in some instances competitive situations might arise in relation to food. However, with one exception, the incidents witnessed were not of an aggressive nature.-FRANCIS S. L. WILLIAMSON and ROBERT RAUSCH, Arctic Health Research Center, United States Public Health Service, Anchorage, Alaska, November 23, 1955.
