Alex Augusto de Abreu Bovo, Katia Maria P. M. B. Ferraz, Luciano M. Verdade, José Roberto Moreira 11 Capybaras (Hydrochoerus hydrochaeris) in Anthropogenic Environments: Challenges and Conflicts Abstract: Capybaras are the largest living rodents, found only in the Neotropics. The species is expanding their range as agricultural deforestation occurs, especially in Southeastern Brazil, Paraguay and Colombia. Major conflicts between capybaras and humans have been described, especially in the context of Brazilian spotted fever (BSF), road kill and crop damage. Even though capybaras are just one of many possible tick- borne hosts, the species has been blamed by the public as the main agent responsible for its occurrence. In addition, capybaras are among the species most frequently involved in road accidents causing extensive damage including human casualties due to its large body size and social behavior. Lastly, the increase of capybara populations in agricultural landscapes may lead to crop damage. Often such conflicts are not well managed, bringing up only short-term solutions that are inefficient in detecting the real problem. Instead of a plague, capybaras should be considered as a great natural resource still lacking the proper public policy to be effectively managed in Brazil. 11.1 Capybaras’ Natural History The capybara, Hydrochoerus hydrochaeris Linnaeus, 1766, is the largest living rodent with maximum dimensions of 1.30 m in length and 70 kg in weight (Ojasti, 1973; Ferraz et al., 2005; Lord, 2009). This species is widespread in Brazil and other countries of South America east of the Andes (Lord, 2009). The capybara family, Hydrochoeridae, includes another asympatric species, Hydrochoerus isthmius Goldman, 1912, which is spatially limited to Panama, Colombia and Venezuela (Moreira et al., 2013; Vucetich et al., 2013). Capybaras are closely associated with aquatic environments, shrub vegetation and grasslands (Ojasti, 1973; Alho et al., 1987a; Herrera & Macdonald, 1989; Moreira & Macdonald, 1997). However, their primary use of water is for thermoregulation (Lord, 2009), reproduction (Azcárate, 1980; Macdonald, 1981) and refuge (Macdonald, 1981). Grasslands are preferred for grazing (Alho et al., 1987a; Macdonald, 1981), while shrub forest is more used for protection against predators, as well as for breeding sites (Herrera & Macdonald, 1989). Several studies have been carried out with the species in two biomes: the Llanos, in Venezuela (Cordero & Ojasti, 1981; Macdonald, 1981; Herrera & Macdonald, 1989) and the Pantanal, on the border between Brazil,