Mink (Mammalia; Carnivora; Mustelidae): correction of a widely quoted error

ABSTRACT Since the European Mink Mustela lutreola and the introduced American Mink M. vison are now sympatric in some parts of the former's native range, and since the two species are similar in appearance, ecology, and behaviour, a need has arisen for a simple way of discriminating live specimens of the two species in the field. Many publications, particularly field guides, have recommended diagnosis on the basis of the presence of white hair on the upper lip of the European species, and its absence in the American species. This is a mistaken suggestion, which should be avoided by authors. American Mink seldom if ever show the large white moustachial bands seen in some European Mink, and may indeed have no white hairs on the upper lip; but white patches of lesser size are common enough to be a possible cause of confusion.