The endangered maned sloth Bradypus torquatus of the Brazilian Atlantic forest: a review and update of geographical distribution and habitat preferences
Hirsch, A. and Chiarello, A.G., 2012. The endangered maned sloth Bradypus torquatus of the Brazilian Atlantic forest: a review and update of geographical distribution and habitat preferences. Mammal Review, 42(1), pp.35-54.
The endemic maned sloth Bradypus torquatus is globally threatened due to deforestation, habitat fragmentation and isolation of populations. Despite increased interest in the species in recent years, information on its geographic distribution is limited and is derived mainly from a few museum species and from a survey based mostly on interviews carried out more than 20 years ago. Information on its habitat and altitudinal preferences is lacking. We therefore compile, update and review all occurrence records of this species using geographical information system (GIS) tools and produce a distribution map for the species.
Our compilation totalled 188 occurrence records, of which 130 (69%) were considered confirmed (museum specimens or individuals captured or seen in the field), most of which (62%) were restricted to the states of Bahia and central-south Espírito Santo (29%). The species occurs predominantly in ombrophilous forest (80%), from sea level to 1290m, but mainly (79%) below 200m altitude.
We used GIS techniques and the alpha shape algorithm to calculate the extent of occurrence of the species and compared the resulting map with distribution maps available in the literature. We found a great deal of variation in distribution area shape and an almost two-fold variation in distribution area size among sources.
We confirmed the existence of a main distribution gap between southern Bahia and northern Espírito Santo and discovered a second smaller gap between southern Espírito Santo and northern Rio de Janeiro.
We also confirmed that B. torquatus is sympatric with the common three-toed sloth Bradypus variegatus in a large part of the Atlantic forest and that the two species are syntopic in at least 11 locations.
Key words: Bradypus, torquatus, ecology, biology, conservation, distribution