Diet and trophic niche breadth of the rare acrobatic cavy Kerodon acrobata (Rodentia: Caviidae) in a seasonal environment

摘要

We investigated diet and feeding behavior of the acrobatic cavy Kerodon acrobata, a rare caviomorph rodent endemic from the Cerrado (Brazilian savannah). We tested whether its trophic niche breadth varies between seasons and whether this species shows seasonal differences in food resource use. Feeding behavior was observed through observations of foraging activities in dry forest associated with limestone outcroppings in central Brazil. K. acrobata showed a generalist diet, feeding on leaves from at least 16 native plant families, also consuming flowers and fruits collected directly from plants or litterfall as well as branches, sprouts, and bark. The diversity of feeding behavior categories did not differ significantly between rainy and dry seasons. The trophic niche breadth considering the plant species consumed, however, decreased during the dry season, when this rodent relied mainly on fallen flowers of Handroanthus serratifolius (Caricaceae; about 44 % of the identified feeding records). The diet of the acrobatic cavy was influenced by the availability of falling leaves and flowers during the dry season, when the animals focused their foraging activities on litterfall. The animals seemed not to extend their behavioral repertoire of foraging in the dry season; instead, they seasonally changed their resource exploitation strategy by altering the proportions of items used and the plant species consumed. The trophic niche breadth and plastic feeding behavior of the acrobatic cavies may explain their persistence in disturbed habitats. Their close relationship with the forests studied indicates the vulnerability of K. acrobata to activities that may threaten the integrity of dry forest areas.