The mysterious white deer: anomalous coloring in different Neotropical deer

Animal coloring serves several functions, including camouflage and thermoregulation. However, some individuals have anomalous coloring patterns due to excess (melanism) or deficiency (albinism, leucism, or piebaldism) in melanin production. Although these anomalies occur in several species, there are few cited cases. Here, we report the occurrence of color anomalies in three Neotropical deer species. Data were obtained from wildlife inventories, through direct observation, camera-traps, and/or deer carcasses, between 2011 and 2020, in three biomes—the Brazilian Savanna (Cerrado), and the Atlantic and Amazon Rain Forests. We registered 10 individuals with anomalous coloring from Minas Gerais, São Paulo, Amazonas and Rondônia states; seven Mazama gouazoubira (six piebalds and one leucistic), two piebald M. americana, and one piebald M. nemorivaga. Of the registered individuals, five were males, two females, and three of undetermined sex. To our knowledge, this is the largest set of anomalous coloring data for Neotropical deer. Even with the increasing reports of anomalous coloring, little is known about the factors that may cause this and how it influences the survival of individuals and consequently wild populations.