| Title: | The deterrent effects of individual monoterpene odours on the dietary decisions of African elephants |
| Author(s): | Bester T; Schmitt MH; Shrader AM; |
| Address: | "Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X28, Pretoria, 0028, South Africa. twanebest@gmail.com. School of Biology and Environmental Sciences, University of Mpumalanga, Private Bag X11283, Nelspruit, 1200, South Africa. Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA, 93106, USA. Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X28, Pretoria, 0028, South Africa" |
| DOI: | 10.1007/s10071-023-01755-4 |
| ISSN/ISBN: | 1435-9456 (Electronic) 1435-9448 (Print) 1435-9448 (Linking) |
| Abstract: | "African savanna elephants use pre-ingestive olfactory cues when making dietary choices, and previous research has observed that elephant diet choice is negatively correlated with vegetation species that contain high concentrations of monoterpenes. However, the frequency and concentration of monoterpenes can vary dramatically across plant species. Thus, we aimed to explore the effects that the odours of individual monoterpenes have on elephant diet choice and how these effects vary with concentration. To do this, we conducted three odour-based choice experiments focusing on eight common monoterpenes found in the woody plants in Southern African savannas. In the first experiment, we tested whether elephant diet choice for a frequently consumed plant (Euclea crispa) was influenced by the addition of the odour of an individual monoterpene at a set concentration. In the second experiment, we explored the relative deterrence of each monoterpene. Lastly, we tested how elephant diet choice varied as a function of the addition of individual monoterpene odours at 5%, 10%, and 20% concentrations. We found that the elephants avoided most individual monoterpenes at high concentrations, with the exception being alpha-pinene. Furthermore, we found that the odours of some individual monoterpenes were, in fact, more deterrent than others. In the third experiment, we found that the elephants avoided beta-pinene, limonene, ocimene, gamma-terpinene, and terpinolene across all concentrations, but only avoided sabinene and linalool at high concentrations. Ultimately, our results show that the odour of individual monoterpenes may deter elephant consumption, but that this deterrent effect depends on both the monoterpene and its concentration" |
| Keywords: | Animals *Monoterpenes/pharmacology *Elephants Odorants Limonene Diet Food preference Foraging Herbivory Olfaction Pre-ingestive cues Volatile organic compounds; |
| Notes: | "MedlineBester, Twane Schmitt, Melissa H Shrader, Adrian M eng 103777/National Research Foundation of South Africa/ Germany 2023/02/18 Anim Cogn. 2023 Jun; 26(3):1049-1063. doi: 10.1007/s10071-023-01755-4. Epub 2023 Feb 17" |
