(Georgia Institute of Technology, 2018-12-06)
Iacono, Jennifer
The African elephant (Loxodonta africana) is a highly social species that typically lives in large, matrilineal family groups called herds which contain a linear dominance hierarchy between the adult females. Management plans for African elephants in human care try to replicate their natural social structures by creating small herds of females but these individuals typically are unrelated except in the case of mothers and their offspring. Despite low genetic relatedness, these females still create their own dominance hierarchies within the herds. Although elephants in human care have all of their needs provided for, dominance within herds can lead to preferential access to high-value resources such as food, water, and shade structures. The purpose of this study was to observe how the two female African elephants at Zoo Atlanta, Tara and Kelly, interacted with each other in terms of their usage of their current exhibit space. An incident occurred during data collection that led to a week-long physical separation of the elephants and the results of this study were then separated into two data sets. Anecdotal evidence of Kelly being the dominant individual was confirmed by Kelly initiating all 110 observed social interactions throughout the course of the study. Tara typically showed her submissiveness by walking away from the interaction. After the incident there was a higher mean frequency of social interactions between the two elephants per hour. The amount of neutral and agonistic behaviors rose as well. It appeared that Kelly was re-establishing her dominance over Tara after their separation. Both elephants had non-random patterns of exhibit spatial use when they were together and when they were alone in the exhibit, as well as before and after the incident. Before the incident, Kelly dominated use of the two areas that had direct access to the indoor barn when both females were in the exhibit together while Tara used the remaining two areas more often. These elephants have a complex social history, which includes Kelly dominating use of the barn and resources after a change to their social structure. As the dominant individual, Kelly had preferential access to this putative high-value area. Kelly continued to stay in the areas closest to the barn when separated from Tara. The pattern of spatial use in the exhibit displayed by Tara when separated from Kelly was different from her pattern when they were together; Tara used the area closest to the barn when alone. The patterns after the incident were similar to those from the before results except Tara used the furthest area from the barn with a higher frequency when alone in the exhibit in addition to the closest. This change may have been caused by Tara’s restricted mobility after the incident. Before the incident all social interactions between the elephants, including agonism, occurred randomly throughout the outside portion of the exhibit despite both elephants having specific patterns in how they used the exhibit. After the incident there was a non-random pattern in the location of all social interactions. More occurred in the area closest to the barn than would be randomly expected, which matches Kelly’s dominating use of that area. Although the occurrence of agonistic behaviors by area changed after the incident, the pattern was still not statistically significant.