African elephants putatively self-medicate with medicinal plants in the Mount Elgon region, Kenya

Abstract The Mount Elgon region in Kenya is renowned for its rich floral biodiversity, its extensive cave systems containing mineral deposits exploited by the elephants and some of the highest density of both total and endemic plant species within the country. This study presents and discusses first-hand accounts from eight local experts from the Sabaot indigenous community, including wildlife community scouts, a retired ranger, and elders, all of whom have witnessed local elephants selectively consuming materials, such as plants, they believe aid in the treatment and prevention of medical disorders. Using semi-structured questionnaires, interviewees linked their indigenous knowledge of local human medicinal resource use to their first-hand observations of elephant dietary behaviors in the region. For the first time in African elephants in the region we report the potential medicinal use of 35 plant species from 23 families, along with four types of soils, minerals or clays. All plant species mentioned in the surveys were taxonomically identified through preparation of herbarium voucher specimens. Interviewees were able to provide specific anecdotes to support these claims for 19 of these zoopharmacognostic resources, including unusual feeding events and specific preparation methods, infrequent targeting of resources, and allocare. Of the 39 total resources mentioned across interviews, informants named 34 (87%) as having traditional human medicinal uses. Of these 34 resources with ethnomedicinal uses, informants identified 25 resources which they perceive to be medicines for elephants. To analyze these interviews and assess the behavioral evidence supporting informants’ claims, we classified each resource into different modes of medication behaviors. In total, eight plant species were classified as Mode 4 (medicines sought by visibly sick elephants for perceived therapeutic purposes or administered to their offspring for their healthcare benefit). These included Aloe arborescens , Bersama abyssinica , Coleus barbatus, Dombeya burgessiae, Dombeya rotundifolia , Dombeya torrida subsp. torrida, Ficus natalensis and Kuloa usambarensis . We also report some notable anecdotes from these interviews which include stories of mother elephants providing medicinal resources to their calves. These first-hand reports from local experts suggest that elephants may intentionally seek out medicinal plants, indicating a targeted rather than random foraging behavior. Taken together, our findings suggest that African elephants may have more diverse and complex medicinal repertoires than previously recognized, and can selectively target these resources when their health is compromised.