Olfaction in megaherbivores: finding food and communicating

Adrian Shrader
Mammal Research Institute, University of Pretoria, South Africa  Shrader@ukzn.ac.za 

(Seminar in English)

EXCEPTIONALLY: IN THE "SALLE DES COLLOQUES" OF THE CNRS DELEGATION (in front of the CEFE) - see map

Many mammals use olfaction to interact with their environment. Yet, very little is known about the olfactory cues and the information they obtain. To address this, we conducted two studies. First, we asked, do African elephants use olfactory cues when making foraging decisions, and if so, at what spatial scale do they use these cues? Working with semi-domesticated elephants, we conducted choice experiments and found that they could locate preferred food plants both within and between patches using only olfactory cues. In a second study, we explored what information is transmitted in the dung odours of the communally defecating white rhinoceros. Obtaining scent samples from free-ranging individuals, we found that white rhinos transmit information about their age, sex, female reproductive state, and male territorial status in the odour profiles of their dung. We then artificially reproduced key elements of the territorial and oestrous odour profiles and exposed free-ranging territorial males to these odours. In response, males elicited behaviours associated with the specific odours, confirming our findings. Ultimately, these results expand our understanding of the use of olfaction by these megaherbivores, and set the ground work for future studies on a wide range on mammal species.

Related publications:

Marneweck, C., Jürgens, A. and Shrader, A.M. 2017. White rhinos transmit key information about their age, sex, male territorial status, and female oestrus state in the odour of their dung. Proceedings of the Royal Society, B 284: 20162376.

Ward, D., Muller, K., and Shrader, A.M. 2017. Are granite-based soils of lower quality than sedimentary soils and how does it relate to plant selection by a megaherbivore? Plant and Soil 413: 73-81.

Schmitt, M.H., Stears, K. and Shrader, A.M. 2016. Zebra reduce predation risk by eavesdropping on cues from giraffe. Behavioral Ecology 27: 1073-1077.