O sagui-da-serra-escuro (Callithrix aurita) e os saguis invasores no Parque Nacional da Serra dos Órgãos, RJ, Brasil: distribuição espacial e estratégias de conservação

Abstract

The Buffy-tufted-ear marmoset (Callithrix aurita) (É.Geoffroy, 1812) is an endemic species of the Atlantic Forest and endangered. Callithrix jacchus and C. penicillata are invasive species in the state of Rio de Janeiro, which compete with C. aurita for the same resources, and form hybrids. In this context, we evaluated the spatial distribution of species of marmosets (native and invasive) in and around the National Park of the Serra dos Órgãos (PARNASO), RJ, Brazil, through using the playback method, interviews, modeling occupation and detection. Furthermore, we compared the actual distribution data with the occurrence of records preceding this study. The results showed that the population of native marmosets and invaders present in the park have similar occupancy probability (0,20 and 0,22), detectability (0,22 and 0,26) and abundance (12,65 and 13,68 groups). The occupancy of the C. aurita is related to the most remote areas of the park road and less human interference, probably due to high altitude in these regions. While the occupancy of the invader marmosets is related to the proximity of the park boundaries and human interference, both at higher altitudes as for minors. We recorded the process of hybridization between native marmosets and invaders, and the formation of mixed groups among them, in various parts of Petropolis, including inside the park, showing the consequences of the invasion process. We concluded that the population of Callithrix aurita in PARNASO is small, restricted to a single region of the park, and some of it has contact with groups of marmosets invaders, or is very close to them. The species of marmoset invaders occur in some places inside the park and all its surroundings. So there is pressure from invader marmosets toward the interior of PARNASO. Given this local extinction process of an endemic species, endangered, and with a restricted range, it alerts to the urgent need to initiate an effective management program of the species of marmosets invaders among the reintroduction of Callithrix aurita groups.