Date of Award

Summer 8-2014

Degree Type


Degree Name

Doctor of Philosophy (PhD)



Committee Chair

Stanley Kuczaj

Committee Chair Department


Committee Member 2

David Echevarria

Committee Member 2 Department


Committee Member 3

John Harsh

Committee Member 3 Department


Committee Member 4

Lance Miller


The current study aimed to assess the effects of two management strategies, weekly rototilling of the enclosure and the provision of unpredictable foraging opportunities, on the daily behavior of six elephants housed at the San Diego Zoo. Observations took place from January to June 2013 and were conducted throughout a 24- hour period. The study was divided into three phases, each two months in duration. During the first phase (baseline) no changes were made to the current management routine of the elephants. In Phase 2, rototilling of the elephant enclosures was increased from once monthly to once per week, while in Phase 3, the elephants were provided with unpredictable foraging opportunities during the day when keepers were present (weekly rototilling continued throughout this phase). Additionally, GPS technology was used to determine the daily walking distances and walking rates of the elephants in each phase of the study, while data loggers were used to determine number and duration of recumbent resting bouts. Activity budgets revealed that the elephants spent a majority of their time feeding (M = 35%, SD = 4.6%) and resting (M = 35%, SD = 8.8%), while behaviors such as locomotion (M = 6.4%, SD = 2.6%) and exploration (M = 4.8%, SD = 1.9%) were relatively low. Comparison of the activity budgets across study phases revealed that weekly rototilling did not have a significant effect on the elephants’ daily behavior, but unpredictable foraging opportunities resulted in a decrease in exploratory behavior (versus baseline) and an increase in stereotypic behavior (versus both baseline and rototilling alone). Average daily walking distances for the elephants ranged from 1.91 to 7.44 km, with walking rates between 0.08 km/hr and 0.31 km/hr, and did not differ significantly across management conditions. Overall, there were substantial individual differences in behavior across subjects in response to the changes in management routine, which may have implications for how these enrichment methods are implemented in the future.