Population density estimation of meso-mammal carnivores using camera traps without the individual recognition in Maduru Oya National Park, Sri Lanka

Abstract

Reliable population estimates are crucial for the conservation and management of faunal species. Population data of meso-mammal carnivores in Sri Lanka, as well as elsewhere in the world, is scarce. We estimated population densities of meso-mammal carnivores in Maduru Oya National Park (MONP) using Random Encounter Model (REM) and Camera Trap Distance Sampling (CTDS) methods in this study. A total of 3,402 camera trapping days yielded 3,357 video captures of 69 different animal taxa including 658 video captures of meso-mammal carnivores. In this study, we recorded all 12 meso-mammal carnivore species found on the island. The two density estimate methods generated similar population estimates indicating that both methods are compatible to be applied in tropical forest habitats for mesocarnivore species. We identify MONP as an area with high richness for the focal species. The study also generated movement speed, activity patterns, activity levels, and day ranges for the focal species, which will be useful for future research. We discuss the population density estimates for different meso-carnivore species and the use of REM and CTDS density estimation methods and their applicability to a tropical meso-carnivore community