Berenty reserve, Madagascar: A long time in a small space

Abstract

Berenty Reserve is a privately owned reserve established in 1936. At 200 ha, it holds the largest remaining gallery forest on the Mandrare River. Scientists of many nationalities have studied there: research follows their diverse interests rather than being coordinated overall. One finding which emerged from long-term monitoring concerns the importance of both within- and between-troop competition for female Lemur catta and their inheritance of territory in the female line, at least in this islanded population. This may play a role in the maintenance of female dominance over males. Another aspect of long-term study is the changes brought by introduced species, including Leucaena leucocephala, a favored, but toxic, forage tree. The growth of leucaena stands paralleled population growth of the L. catta troops with access to these stands, although highly affected females lost fur and had low infant survival; eradication produced a local population crash. Introduced Eulemur rufus x collaris have grown from about 16 individuals in 1975-1980 to almost 600 in 2009. They are taking over the central gallery forest. L. catta troops maintain their original sleeping areas in the gallery forest but increasingly forage on the periphery, recreating the niche separation described for Lemur and Eulemur in natural sympatry. Overall, Berenty Reserve is drying out, with closed-canopy gallery forest giving way to more open scrub. Research on Berenty's lemurs is thus the study of evolved adaptations confronted with a changing environment.