Dietary composition and foraging habitats of the Indian Pangolin (Manis crassicaudata) in a tropical lowland forest-associated landscape in southwest Sri Lanka

Abstract

The Indian pangolin (Manis crassicaudata) has a wide distribution in the Indian subcontinent and is a threatened species throughout its range due to hunting, poaching, trafficking, and destruction of natural habitats. Many rescue programmes for Indian pangolins have had limited success due to the paucity of literature on the diet, ecology and its behaviour. This study investigated the dietary composition and foraging habitat preference of the Indian pangolin in a tropical lowland forest-associated landscape of Southwest Sri Lanka. Five types of habitat were considered in this study: forest, rubber plantation, cinnamon cultivation, oil palm plantation, and tea-dominated home gardens/cultivated areas. The foraging intensity of Indian pangolin in the five habitat types was assessed using signs of foraging activities observed in five 10 × 10 m plots placed along a transect. Ten transects were established in each habitat assessed. The forest habitat was preferred in the studied landscape, followed by rubber plantations, the cinnamon cultivations, oil palm plantations and the tea-dominated home gardens/cultivated areas. Indian pangolins mostly predated on termites, as indicated by the number of feeding events on termitaria and termite-infested logs. Faecal content analysis further revealed that the undigested matter (by weight) was predominantly composed of grit (53.3%), insect matter (37%) and plant matter (9.7%). The digestibility of termite heads, mouthparts, abdomens, and legs was high compared to that of ants. This difference in digestibility was evident from the presence of significantly more heads, mouthparts, abdomens, and legs of ants in the faecal matter, compared to that of termites. However, undigested termite wings were frequently observed in the faecal matter. Termites of the genus Odontotermes and ants of the genera Oecophylla, Anoplolepis, Camponotus and Monomorium were the main prey species of the Indian pangolin in the studied area. The findings on the dietary composition have implications in captive rearing and husbandry of Indian pangolins. In addition to natural forests, the findings of the study suggest that human-modified agricultural lands adjoining forest also serve as important as foraging habitats for Indian pangolins, and such habitats should be considered in long-term conservation planning.