The crab-eating fox (Cerdocyon thous (Linnaeus, 1766)) and the raccoon (Procyon cancrivorus (Cuvier, 1798)) are medium-sized nocturnal carnivores (3–8 kg) belonging, respectively, to families Canidae and Procyonidae (Berta 1982, Langguth 1975, Yanosky & Mercolli 1993). Both are widely distributed over the Neotropical Region (Colombia, Venezuela, Guyana, Surinam, French Guiana, Paraguay, Uruguay, northern Argentina and the greater part of Brazil) (Berta 1982, Brady 1979, Langguth 1975, Santos & Hartz 1999), being sympatric over most of their range. In Brazil both species are found in various different habitats, including the coastal plains (restingas) (Berta 1987, Langguth 1975, Motta-Junior et al. 1994, Novaes 2002, Santos & Hartz 1999, Wang & Sampaio 2001).