Share Content Published December 15, 2015 RD-151215011 Two Harris Hawks (Parabuteo unicinctus), one immature and one adult, perched on a tree branch with wings spread against a blue sky in the Sonoran Desert of Tucson (Arizona) accipitridae adult animal arizona aves bird bird of prey blue sky buteoninae falconiformes harris hawk harriss hawk hawk immature juvenile landing north america parabuteo parabuteo unicinctus predator raptor sonoran desert tucson two usa vertebrata vertebrate wings spread