Hunting and scavenging of vertebrates by nonhuman primates has been recorded widely across the world (Butynski, 1982). Researchers have observed predation of small amphibians, reptiles, birds and mammals by several different primate species (Boinski and Timm, 1985; Wrangham and Riss, 1990; Heymann et al., 2000; Poulsen and Clark, 2001; Begotti and Landesmann 2008; Silva et al., 2008). However, capuchins, chimpanzees and baboons are the only non-human primates known to prey systematically upon relatively large vertebrates (Rose, 1997). Capuchin monkeys have consumed a variety of vertebrate prey such as frogs (Izawa, 1978); lizards, birds, bats (Fedigan, 1990; Rose, 1997; Rose et al., 2003); opossums (Didelphis sp.), rats (Rattus rattus) (Resende et al., 2003); mice (Rhipidomys sp.) (Milano and Monteiro-Filho, 2009); squirrels (Sciurus aestuans, S. variegatoides) (Galletti, 1990; Cunha et al., 2006); coati pups (Nasua narica) (Newcomer and Fancy, 1985; Fedigan, 1990; Perry and Rose, 1994; Rose et al., 2003); anteater juveniles (Tamandua mexicana) (Rose et al., 2003); and even other primates, such as titi monkeys, Callicebus moloch (Sampaio and Ferrari, 2005), and owl monkeys, Aotus brumbacki (Carretero-Pinzon et al., 2008). Here we describe an opportunistic attack attempt on a road-killed brown-eared woolly opossum (Caluromys lanatus) by a black-horned capuchin monkey (Sapajus nigritus) during a fortuitous encounter in a disturbed fragment in the Brazilian Atlantic Forest.
Figure 1.
(a) Road-killed Brown-eared woolly opossum (Caluromys lanatus) and (b) Black-horned capuchin (Sapajus nigritus) in the Ecological Station of Ribeirão Preto, northeastern of São Paulo state, Brazil (Photos: Camila Camara Pianca).
On November, 30th, 2003, at around 1000 h, we collected ad libitum data on a black-horned capuchin attacking a brown-eared woolly opossum that had been hit by a car, in the Ecological Station of Ribeirão Preto, Mata Santa Tereza (21°12′57″ S; 47°50′52″ W), a semi-urban area of 154.16 ha in Ribeirão Preto, in the northeast of São Paulo state, Brazil. Mata Santa Tereza is an isolated forest fragment and has a large population of these capuchin monkeys (Amaral et al., 2005). Although the group has been well studied (Siemers, 2000; Amaral et al., 2005; Machado et al., 2012), this is the first report of this particular behavior. The brown-eared woolly opossum was still alive on the ground, with its organs exposed (Fig. 1a), when an adult male black-horned capuchin monkey, that was standing on the ground (Fig. 1b), approached the fatally injured woolly opossum and started to attack the animal viscera while the rest of the capuchin group watched at the edge of the road. There was high traffic volume on the road that day, and the predation attempt was interrupted by the approach of a car, which caused the capuchin to run away towards the forest adjacent to the road.
Perhaps, Mata Santa Tereza does not have enough feeding resources to support this large monkey population and food shortage is a common situation faced by the group. It may also be important that, especially on weekends and holidays, local people feed these capuchins a variety of foods such as bananas, eggs, peanuts, bread and other snacks. In most cases, individuals descend to the ground to get the food from the visitors' hands. So, these monkeys may have learned to patrol the road for people's food and also are aware of other opportunities such as road-killed animals, which could serve as alternative food source available in this area. Siemers (2000) observed that the capuchins of Mata Santa Tereza remained on the forest floor and did not flee to higher strata when humans passed. They often foraged for food voluntarily or accidentally dropped by humans on the ground. Also, the monkeys predominantly traveled in low forest strata and spent more time close to the ground than in the canopy.
In general, predation of mammals or other vertebrates by monkeys is usually performed during a period of food shortage or through intraspecific social learning (Resende et al., 2004). Apparently, seasonality is not an important factor in the occurrence of vertebrate predation by capuchins. Different surveys on predation by capuchins have been recorded during the dry season which is also the birthing season of most prey species (Fedigan, 1990), but also in the wet season (Rose, 1997) or even with the same frequency in dry and wet seasons (Ferreira et al., 2002). Apparently, there is a sex difference in frequency of predation by capuchins, since adult males tend to catch more prey than females (Fedigan, 1990; Rose, 1997; Ferreira et al., 2002). In addition, capuchins tend to select prey items by size and age; for example, they preferentially search for infants or juveniles of large mammals, such as for coatis, anteaters and other primates (Rose, 1997; Rose et al., 2003; Sampaio and Ferrari, 2005). However, injured or killed animals could be consumed opportunistically by capuchins regardless of their age or size (Carretero-Pinzón et al., 2008). Therefore, further detailed surveys are needed to determine the conditions under which predation of large mammals by capuchin monkeys can occur.
Acknowledgments
We would like to thank our parents, Benvinda Belem Lopes, Antonio Carlos Pianca and Rosa Maria Correa Camara Pianca for their support in this field research. We also thank Carlos Eduardo Marinelli and Cristiano Trape Trinca for their comments and suggestions on the early version of the manuscript. We are very grateful to Jessica Lynch Alfaro for her revisions and comments.
