A Leucisitic Fisher (Pekania pennanti) and the Prevalence of Leucism in Wild Carnivores

Animal coloration has adaptive roles for communication, concealment, sexual selection, and physiological function. Genetic mutations sometimes cause abnormal coloration such as leucism, in which an animal appears partially or entirely white, except for exposed soft skin tissue. Here we document a leucistic fisher (Pekania pennanti). Fisher fur normally ranges from deep brown to black, but the function of the pelt color is not understood. The literature on the occurrence of leucism includes 33 other records of leucism among carnivores. Reporting cases of rare coloration in the wild helps to understand the distribution, prevalence, and significance of abnormal colors.