Saturday, September 27, 2014

Sharp-shinned Hawk

In Minnesota, Sharp-shinned Hawks generally breed north of Interstate 94. Only about a half-dozen summer records exist in eBird south of that line in our state. This individual acquired a bird band after hitting our net. Fortunately no small birds or large banders were harmed during this incident. Bildstein and Meyer (2000) write, “although small mammals and even insects appear in its diet, this forest-dwelling predator feeds almost entirely on small birds.” I respectfully held the hawk as Erika took this photo in the sunlight with the dark forest interior as a backdrop.

These authors also contend that, with males only averaging 57% of the female’s in body mass, this species is the most sexually dimorphic of North American hawks. With a wing chord of 206 mm, this Accipiter must be a female Sharp-shinned Hawk. (The mean for male wing chords is 169 mm; females average 200 mm, with no overlap between the sexes (Mueller et al. 1981).) The yellow eye indicates an immature bird.

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