UC Berkeley

Tamarins (gen. Leontocebus and Saguinus) are small, charismatic, ecologically vital, and socioecologically atypical Neotropical primates. Their behavior, especially their habitat needs and their social use of space, can help address questions regarding the evolution of social behavior in primates as well as conservation problems regarding the health and viability of anthropogenically disturbed rainforest habitat. This dissertation was conducted on sympatric populations of saddleback tamarins (Leontocebus weddelli) and emperor tamarins (Saguinus imperator) at Los Amigos Biological Station in Madre de Dios, Peru, and analyzes the intersection of tamarin behavioral and spatial ecology from three distinct angles. Chapter 1 introduces the study system and data collection methods used throughout the dissertation. Chapter 2 uses high-resolution environmental imaging in combination with machine learning to characterize microhabitat use and the spatial distribution of critical sleeping and foraging behaviors. Chapter 3 describes the behavior of two individuals observed opportunistically during their transient phase, a critical period in which animals live alone, often in unfamiliar terrain, as part of their search for breeding opportunities. Chapter 4 tests the theory of home range size, using a multi-year dataset to assess whether larger groups travel farther and occupy larger ranges as predicted by socioecological theory. All three major projects are made possible by the presence of two sympatric tamarin species in a single small area of Amazonian rainforest, which facilitates both interspecific and intraspecific comparisons.