Several Lemur catta troops at Berenty, Madagascar have been censused repeatedly since 1963. In 1972, the entire reserve was censused. A recensus in 1975 showed that although some minor changes have occurred in the number of animals in individual troops, the population of the reserve as a whole, the core areas of the lemurs’ territories, and their home range boundaries have all remained stable ever since the first complete census 3 years earlier.