Census and distribution of the golden lion tamarin (Leontopithecus rosalia)

During 1990-1992, a survey of the golden lion tamarin, Leontopithecus rosalia, was carried out throughout its known distribution area. Forest remnants were identified by visual interpretation of Landsat-TM satellite images. Localities occupied by L. rosalia were first identified by interviews with local people. All forests more than 20 ha in size, and for which two or more interviews suggested the presence of the species, were surveyed using "play-back" recordings of lion tamarin long calls. The total wild population of L. rosalia, including that of the Poço das Antas Biological Reserve, was estimated to be 562 individuals in 109 groups. The lion tamarins were generally found in four major areas of forest (six or more groups per forest, not including Poço das Antas), with a further 12 groups isolated in small forest patches. Currently the species' distribution is restricted to just four municipalities in the state of Rio de Janeiro: Silva Jardim, Cabo Frio, Saquarema, and Araruama. Although they are typically confined to lowland forest of <300 m altitude, L. rosalia was recorded at an altitude of 550 m in one locality. Average group size varied from 3.6 to 5.7 individuals, and densities from 0.39 groups/km(2) to 2.35 groups/km(2) (2.17 individuals/ km(2) to 8.53 individuals/km(2)). Six of the isolated groups found during the survey were successfully translocated to a forest of 2400 ha. There is now also a significant population of reintroduced lion tamarins. Overall, however, the possibilities for further expansion of the wild population are severely limited.