The southern muriqui, Brachyteles arachnoides : ecology of a population in a semideciduous forest fragment

Abstract

Southern muriquis (Brachyteles arachnoides) inhabit evergreen and semideciduous forest fragments in southeastern Brazil. Contrary to the broadleaf evergreen forests, the seasonal mesophytic forests experience a relatively severe dry season, which affects the muriquis’ diet. Through behavioral sampling of feeding activity, I determined the diet of a group of muriquis in a semideciduous forest fragment. Leaves represented 55.3% of feeding records, flowers 16.1%, fruits 12.1%, and seeds 16.5%. Muriquis included 47 plant species in their diet. Leaf consumption was significantly higher in the dry season, but there was no evident difference between seasons in their feeding on either flowers, fruits, or seeds. Muriquis in this study shared only 11 taxa with groups in evergreen forests. The study group made consistent use of immature seeds. Dietary flex- ibility and the consumption of alternative resources may likely be advantageous where there are repeated lean periods and anthropogenic interference.