Madagascar is a 1650 km- (1025 mi-)long island divided by a mountain chain running the length of the island from north to south. This mountainous divide partitions Madagascar into eastern and western parts, each of which has distinctive climate, topography, and vegetation (Jury 2003). Ring-tailed lemurs are found in the southeastern portion of the island at elevations from sea level to 2600 m (8530 ft) in a variety of habitat types including rainforests, subalpine, deciduous, gallery, and spiny bush forests (Goodman & Langrand 1996; Goodman et al. 2003). Much of their habitat has been altered by human impact through clearing for agriculture, burning for charcoal production, and deforesting areas to create settlements (Sussman et al. 2003). Ring-tailed lemurs require some forest cover and are not successful at resettling in secondary growth areas once they have been cleared therefore the total range occupied is large, but their distribution is patchy and dependent on forest cover (Jolly 2003).