Ecophysiology of elephants to better understand their crop selection: first results of a case study in Monts de Cristal, Gabon

Parasites and hormones are one of the best indicators of animal ecophysiology which clarify the role and importance of physiological processes in the ecological relations of species in their natural habitat. As damages on crops are often sources of conflict between humans and elephants in elephant home ranges, few data on the relevance of elephant physiology on crop selection exist. For that we investigate elephant ecophysiology to better understand if their parasitism and stress conditions underlie their crops selection. For that we measured parasite loads and stress hormone levels in feces of some elephants eating banana and others eating natural food. We conducted the study during fifteen months covering five different local seasons of the research site in Mont de Cristal, Gabon. Here we report first results from two seasons.
We collected 485 samples of elephant dungs and more than 1200 samples of food items eaten by elephants. While stress levels are not correlated to banana selection, the presence of parasites is. Our results show higher parasite loads in dungs of elephants eating banana than in those of elephants eating natural food resources species. Thus elephants may eat banana more as a medicine item than a food resource. But we still need to confirm these results by assessing this trend over seasons and with reproduction hormones.