Tree diversity mediates individual diet specialization of the maned sloth (Bradypus torquatus)

Individual diet specialization is commonly found in generalist species but has been little studied in folivore mammals. Empirical evidence shows that the diversity of food resources in the habitat affects the degree of this specialization, by influencing among-individual diet variation (diet similarity) and individual niche breadth (diet diversity). We aim to evaluate the diet composition and selection of maned sloths ( Bradypus torquatus , Illiger 1811) in two distinct ecological contexts; test whether the diet similarity between individuals and populations is explained by changes in the local floristic compositions and/or by a differentiated selection of tree species, and evaluate the effect of the local tree diversity on the diet diversity and similarity across individuals. We monitored 13 individuals in northern Bahia and Rio de Janeiro and accessed the tree species diversity and availability within each home range. We identified 67 tree species consumed, most of which were consumed in higher proportion than their availability in the home ranges, indicating high selectivity by the individuals. Diet similarity decreased with greater differences in the local floristic composition and higher tree diversity, but was also influenced by individual selection. Together, our results evidence that the maned sloth is specialist and selective at the individual level, and the lower tree diversity reduces individual diet specialization, revealing tree species that are commonly preferred at the population level under such condition. Our results can be directly applied to feeding protocols of captive populations, and ecological restoration initiatives focusing on the conservation of this threatened species.