Publication Date

8-2012

Advisor(s) - Committee Chair

Dr. Bruce A. Schulte (Director), Dr. Carl Dick, Dr. Michael Collyer, Dr. Keith Philips

Degree Program

Department of Biology

Degree Type

Master of Science

Abstract

Perceived predation risk alters animals’ behavior. This shift in behavior often comes at the cost of attaining resources. Generally, African elephants (Loxodonta africana) experience little predation pressure; however, the risk of predation by lions (Panthera leo) increases other prey species are less abundant. In elephant herds, related females and their offspring travel together in family groups, led by the eldest female. Response to predation pressure was examined by playing lion calls to the population of 437 elephants at the Main Camp Section of Addo Elephant National Park (AENP) in South Africa. Unfamiliar lion calls from a single male and two males, static, and running water were played from a remote speaker to elephants at waterholes. These trials were recorded by video. Behaviors of elephants were then extracted from video into focal observations of thirty second segments before, during and after a sound was played. I analyzed these data using parametric t-tests and non-parametric randomization tests. When no sound was played, elephants did not alter their behavior. Water elicited low levels of distress behaviors. Elephants behaved in a threatened or annoyed manner toward static. Elephants changed their behavior more in response to lion calls than to the controls, namely by decreasing drinking and increasing walking and distress behaviors. I also examined how individuals differed in their responses to the lion calls based on a number of demographic factors. Adult and subadult females performed more social behaviors after lion calls when the matriarch was absent than when she was present. Furthermore, when group size was larger and more calves were present, females decreased drinking and increased time exhibiting distress behaviors. Based on this and other studies it can be concluded that elephants of different demographics perceived similar levels of elevated risk when hearing lion calls. Landscape of fear models are useful for assessing habitat use by prey species in response to real and perceived predation risk. The present study corroborates findings from a study in East Africa that elephants perceive threat from lions based on calls alone and appear to distinguish levels of threat by the number of lions calling.

Disciplines

Biology

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