Frugivory and potential seed dispersal by the exotic-invasive marmoset Callithrix jacchus (Primates, Callitrichidae) in an urban Atlantic Forest, Rio de Janeiro, Brazil

The common marmoset, originally from Northeastern Brazil, has been introduced into several Brazilian states as a result of illegal traffic. Despite the long history of introduction, few studies have described the diet of this primate in regions where it is exotic and none have evaluated its role as a seed disperser. The importance of fruits in the diet of Callithrix jacchus and its potential as a seed disperser were investigated in the Tijuca National Park (TNP, 3.593 ha), southeastern Brazil, where the species is exotic. Data were collected from September 2013 to January 2015, through focal observations. A sampling effort of 361 h of observation resulted in 60 independent feeding records. Fruits were the most often consumed item, comprising 483% of the observed feeding records, followed by gum (30%), invertebrates (18.3%) and lichens (3.3%). Seeds from four out of 13 species were swallowed and seeds from seven additional species were found intact in collected feces. These results show C. jacchus' potential to act as a seed disperser for some plant species, and that should be considered for managing this primate in TNP, where other callitrichids are absent.