. Bulletin of the British Ornithologists' Club. Birds. In Brief 192 Bull.B.O.C. 1998 118(3). Figure 1. Three female and one male Accipiter striatus perobscurus, all juveniles. Dark-morph individuals usually show all dark underwing coverts and lack pale supercilia. We have no arguments with the interesting discussion of dichromatism in raptors that follows the brief description of the hawk in question. According to Terres (1980), 'dark morph' is a regularly occurring colour morph, whereas 'melanistic' is an abnormal plumage. As this species does not have a described dark morph, the hawk referre
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. Bulletin of the British Ornithologists' Club. Birds. In Brief 192 Bull.B.O.C. 1998 118(3). Figure 1. Three female and one male Accipiter striatus perobscurus, all juveniles. Dark-morph individuals usually show all dark underwing coverts and lack pale supercilia. We have no arguments with the interesting discussion of dichromatism in raptors that follows the brief description of the hawk in question. According to Terres (1980), 'dark morph' is a regularly occurring colour morph, whereas 'melanistic' is an abnormal plumage. As this species does not have a described dark morph, the hawk referred to in this article is therefore an alleged melanistic. The specimens of ^. s. perobscurus shown in Figure 1 were collected in the breeding range of this race, the humid temperate forests of coastal Washington and British Columbia, to the north of the California location of the hawk in question. This darker coloration, no doubt a perfect example of Gloger's Rule, is shown on several other raptor species in this range, e.g. Merlin Falco columbarius suckleyi and Northern Goshawk Accipiter gentilis laingi. Dark Merlins are regularly recorded in California. It is not clear why there are no official records of ^. s. perobscurus from California, as a juvenile of this race, found dead in southern California, was prepared as a specimen and deposited in the collection of Rio Hondo College in Whittier by John Schmitt (pers. comm.), and a specimen of a juvenile male of this race in the National Museum of Natural History was collected in Lassen Park, California, in 1908. In summary, it is most likely that the hawk reported in Patten & Wilson (1996) is a darker female of the race Accipiter striatus. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. British Ornithologists' Club. London : The Club