Diet and nutrient balance of wild Asian Elephants Elephas maximus in Nepal

We estimated the nutritional content of major wild (n = 22) and agricultural crop plants (n = 3) consumed by Asian Elephants Elephas maximus in Nepal during the wet and dry seasons, respectively. We then used nutritional geometry to explore the macronutrient balance of these plant species, as well as the overall diet of elephants in both the dry and wet seasons. Furthermore, we compared the diet of the Nepal elephants with the previously published diet of Indian population of elephants. We found that despite intraspecific and seasonal variation, the overall diet of elephants was relatively stable in protein (P) intake relative to non-protein macronutrients (fat + carbohydrate; non-protein (NP)), and neutral detergent fibre (NDF) between the wet (16% crude protein (CP): 26.7 % NP: 57.3% NDF; and, 10.4% CP: 13.7% NP: 75.7% NDF) in dry season, which suggests protein intake prioritization in support of previous work on captive elephants. Furthermore, the diet of Indian population of elephants (wet season: 16.0%P: 22.5%NP: 61.4%NDF and dry season: 11.1%P: 18.0 %NP: 70.7 %NDF) showed a similar pattern to the Nepal elephants, suggesting active regulation of macronutrient and NDF intake across populations despite differences in food consumed as part of their diets. Importantly, NDF intake in addition to non-protein macronutrients is likely necessary for elephants to stabilize their protein intake balance; thus, it is important to consider a multidimensional nutritional perspective in elephant conservation planning. The study has concluded that in a well-managed seasonal habitat, elephants can regulate their preferred macronutrient and NDF intake from available natural food plants without resorting to agricultural crop depredation.