Home range of a Geoffroy's marmoset group, Callithrix geoffroyi (Primates, Callitrichidae) in South-eastern Brazil

Abstract

The home range of one group of the Geoffroy's marmoset (Callithrix geoffroyi) was studied in a fragment of the Atlantic Forest in south-eastern Brazil, between February 1993 and January 1994. The total home range was 23.3 ha and the area used in the dry season was significantly larger than that of the wet season. The smallest distance travelled by group was 480 m/day in May and the longest was 1,980 m/day in March, but with no significant differences between seasons. The total home range used for this species agrees with the ecological grouping of the genus Callithrix proposed by Rylands & Faria (1993) and may be associated with the habitat structure, the limit of the fragment and the inexistence of neighbouring groups.

Seasonal variations in spatial usage by the estuarine dolphin, Sotalia guianensis (van Bénéden, 1864) (Cetacea; Delphinidae) at its southern limit of distribution

“…Based on the diet of the dolphins and on the seasonal variation of abundance of dominant prey types (especially fish from the Engraulidae Family), it has been hypothesized that the greater spatial requirements of the estuarine dolphins in the cold seasons were due to a lower abundance of food resources, whereas the opposite occurs in the summer (Daura-Jorge, 2003;Wedekin, 2003;Daura-Jorge et al, 2004). The negative relationship between the abundance of major food items and the size of the area used by individuals or groups has also been found in primates (Passamani and Rylands, 2000;Castro, 2003) and in one small cervid species (Tufto et al,996).…”

“…For this reason, even considering that occasional large-scale individual movements and dispersal may occur, the group home-range concept was applied in the present study in the same way as it is applied in some primate social group studies (e.g. Stacey, 986;Passamani and Rylands, 2000;Castro, 2003).…”

Edge effects and their influence on lemur density and distribution in Southeast Madagascar

“…Thus, M. rufus, C. major, and D. madagascariensis should be omnipresent in forest fragments. Insectivores may prefer forest edges because of abundant insect prey in this microhabitat (Passamani and Rylands, 2000;Spironello, 2001). Based on these assumptions, omnivores with a diet composed of insects (M. rufus) should range nearer to forest edges than omnivores that rarely eat insects (C. major and D. madagascariensis).…”

Tamanho da área de vida e padrão de uso do espaço em grupos de sagüis, Callithrix jacchus (Linnaeus) (Primates, Callitrichidae)

“…Durante os outros meses o grupo utilizou um espaço maior devido à necessidade, frente à escassez de frutos, de utilizar um maior número de árvores de goma (PASSAMANI & RYLANDS 2000).…”