Fossil Red-shouldered Hawk in the Bahamas: Calohierax quadratus Wetmore synonymized with Buteo lineatus (Gmelin)

Abstract

A supposedly extinct genus and species of hawk, Calohierax quadratus Wetmore, was originally described from a fragmentary tarsometatarsus from Quaternary deposits in Little Exuma Island in the Bahamas. This and a referred tibiotarsus from New Providence, Island, were later assigned to the extant genus Buteo, but their specific identity remained uncertain. A previously unstudied humerus from a cave deposit on New Providence Island, Bahamas, is here identified with the extant Red-shouldered Hawk, Buteo lineatus Gmelin, a species widespread in eastern North America and common in peninsular Florida but unknown in the Bahamas. The other fossils ate assigned to this species as well. Calohierax quadratus therefore becomes a synonym of Buteo lineatus, which species has retreated from the Bahamas in the late Quaternary for reasons that are unclear.