‘How much and of what?’ Biomass consumption from prey occurrences in scats of tropical felids.
Wildlife Institute Of India
Relationship between biomass consumed per collectable scat and prey weight, to convert frequency of prey remains in scats to actual consumption, is absent for Indian felids. Dietary studies of Indian felids have used a relation based on a temperate predator (Ackerman et al. 1984), which might be improper due to difference in prey-predator essentialities among temperate and tropical system. Herein, we developed biomass models for Asiatic lion, leopard and jungle cat.
Forty four feeding trials, using a combination of wild and domestic prey representing the entire prey weight range of lion, leopard and jungle cat in the wild, were conducted over a four month period (January-April, 2013) on wild caught carnivores in Sakkarbaug zoo, Gujarat. Biomass consumed per collectable scat was regressed against mean prey weight to derive biomass models. Published literature on diet of Indian felids were re-analysed using present study models.
Contrary to Ackerman’s model, present study models were described by non-linear functions. Models for lion and leopard differed significantly from Ackerman’s model. The three models when scaled to their respective carnivore body masses did not differ significantly, allowing us to construct a generalized biomass model for tropical felids. This generalized equation could be used for any tropical felid, for better representation of diet.
The biomass models derived in the current study significantly altered hitherto interpretation of Indian carnivore diet, reducing large prey and increasing medium sized prey consumption by big cats. This is relevant for better interpretation of scat-based studies of carnivore diet and understanding actual scales of human-carnivore conflict by refining livestock depredation rates.