(Photo by Anna Fasoli)
We determined the hawk is an Intermediate Morph Adult Rough-legged Hawk. The "intermediate" morph is sometimes considered a heavily marked "light morph" type.
The following criteria was used to come to this conclusion; dark underwing coverts, dark and very obvious subterminal band on the trailing edge of the wings, dark underside with very dark areas creating a belly-band and a dark breast, light-colored tail with a very dark subterminal band shown on both the upperside and underside. That last bit of info is crucial for deciding the bird was not a dark morph since on a dark morph, the upperside of the tail would be dark and not shown any white on a dark morphed bird. As far as why the bird is not a juvenile, the upperside of the wings were solid dark brown. In a juvenile, the upperside of the wings would be light brown/grayish on the primary flight feathers much like how a juvenile Red-tailed Hawk has lighter-colored primary feathers on the upperside of the wing. (Photos below were taken by Alex Lamoreaux)
The following criteria was used to come to this conclusion; dark underwing coverts, dark and very obvious subterminal band on the trailing edge of the wings, dark underside with very dark areas creating a belly-band and a dark breast, light-colored tail with a very dark subterminal band shown on both the upperside and underside. That last bit of info is crucial for deciding the bird was not a dark morph since on a dark morph, the upperside of the tail would be dark and not shown any white on a dark morphed bird. As far as why the bird is not a juvenile, the upperside of the wings were solid dark brown. In a juvenile, the upperside of the wings would be light brown/grayish on the primary flight feathers much like how a juvenile Red-tailed Hawk has lighter-colored primary feathers on the upperside of the wing. (Photos below were taken by Alex Lamoreaux)
References:
Wheeler, Brian K. Raptors of Eastern North America. Princeton, NJ: Princeton UP, 2007
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