ECOLOGY AND DEMOGRAPHY OF GOLDEN-HEADED LION TAMARINS (Leontopithecus chrysomelas) IN CABRUCA AGROFOREST, BAHIA STATE, BRAZIL.

Abstract

Understanding how species use the matrix of habitat that surrounds forest fragments can contribute to conservation strategies in fragmented landscapes. In this dissertation, I evaluate the effects of habitat structure and resource availability on group characteristics, use of space, and predation risk for the endangered golden-headed-lion tamarins in shaded cocoa plantations locally known as cabruca agroforest. In the first chapter I present a list of tree species that provide key foods and sleeping sites used by lion tamarins. Families Myrtaceae and Sapotaceae are the most commonly used by lion tamarins for both food and sleeping sites. Fifty-five tree species were ranked as extremely valuable for the tamarins. Cabruca management that retains the species listed in this study may improve the long-term survival of lion tamarins. In the second chapter, I compare ecological and demographic data of lion tamarins in cabruca and other vegetation types. In contrast with my prediction that food resources would be scarce in cabruca, the exotic and invasive jackfruit (Artocarpus heterophyllus) was an abundant food resource for tamarins in cabruca while bromeliads were the favorite substrate for animal prey foraging. Group size and composition were similar in all vegetation types. Males in cabruca were heavier than those in primary forest. Density of lion tamarins in cabruca was the highest and home range size the smallest reported for the species. This is the first study to show that lion tamarins can live and reproduce exclusively in cabruca and has important implications for conservation of the species. In my third chapter, I test two hypotheses explaining the association between lion tamarins and Wied's marmoset (Callithrix kuhlii): foraging benefits and predation avoidance. I found no evidence to support the hypothesis that interspecific associations provide foraging benefits for lion tamarins. However, several findings support the predation avoidance hypothesis: associations occurred in areas where predation risk was higher, and during the part of the day in which predation risk was highest, and following birth events when the tamarins were more susceptible to predation. Despite the importance of cabruca to lion tamarins, they are more exposed to predation in this habitat.