Small carnivores adapt to hunt in moonless nights to avoid big cats
DEHRADUN : Smaller carnivores, mainly belonging to cat and civet family, of Assam’s Manas National Park have adapted to hunt in dark nights to avoid predation by larger carnivores, says an ongoing study of Dehradun-based Wildlife Institute of India (WII).
The research that will conclude next year outlines how moon illumination influences mammal activity in the protected area. Large carnivores like tigers and leopards were active during various nights but small carnivores as a strategy to avoid predation seem to be significantly more active during darker nights, when they could hide from large carnivores easily.
“Small carnivores showed significantly high activity in darker nights, and these patterns indicate that small predators may defer their activity temporally as an anti-predator strategy to co-exist with large carnivores or otherwise to increase their foraging efficiency,” Salvador Lyngdoh, principal investigator and scientist heading the research said.
Small carnivores that were found to be nocturnal in Manas are jungle cat, leopard cat, large Indian civet, small Indian civet, Chinese ferret badger.
Camera traps were deployed in Manas from April 2017 till May 2018. The activity periods of 35 mammals were classified as diurnal (active during daytime), nocturnal (active during night-time), crepuscular (active in twilight) and cathemeral (evenly active during 24 hours a day).
Most of the scientific literature shows that moonlight seems to increase predation risk by enhancing the ability of predators to detect prey, thus leading to reduced activity or shifts in prey activity in brighter nights or moonlight. Moonlight also seems to influence positively the activity of those animals which depended on sight mainly, while suppresses those which depend on other senses like smell. In short, moonlight influences mainly the prey activity to avoid predation and enable better food search.
“In our study, the activity during moon phases of top predators like tiger and leopard was cyclic in manner, which means they have a regular peak and valley pattern and hence were not significantly correlated with moon cycle,” Salvador added.
“This study is a comparison of activity patterns across the various phases of the moon cycle,” he said.