Zebra are highly social ungulates that live in harems with a dominance hierarchy. This study attempted to determine if dominance rank within a herd of Burchell’s zebra (Equus burchelli) correlated to frequencies of other behaviors. It was predicted that adult zebra would display the most vigilance, with vigilance decreasing with dominance rank. This study took place at Ndarakwai Ranch in the west Kilimanjaro basin of northern Tanzania from 11/7/10 until 11/22/10. Scans (n=199), follows, and all-group observations were used to collect data on opportunistic sightings of Burchell’s zebra. Zebra were categorized into five age classes: stallion, adult females, sub-adults, juveniles, and infants and behavior was recorded in frequency tables. Pie-charts were used to display each age class and its percentage of each behavior, which included moving, feeding, resting, vigilance, and other. Chi-squared (α=0.05, df=4) was used to compare all age-classes to every other age-class using a critical value of 9.488. Eight statistically significant results were produced between age-class comparisons. It was found that within these eight age class comparisons, behavior was not independent of dominance rank. The two age-class comparisons that did not reject H0 were found to be in comparison to infants, who were not observed for very long periods of time. The hypotheses formulated before the study were found to be true, with the stallion most often located on the periphery of the herd and displays of vigilance decreasing as dominance rank decreased. It seen that as the number of zebra in the proximity increased, vigilance decreased through all age groups, and more playful behavior was seen. Variables such as habitat and proximity to other herds of mammals were seen to have no effect on zebra behavior.
Animal Sciences | Zoology
Clayton, Alexandra, "Seeing Stripes: A Study of How Dominance Rank Within a Herd of Resident Burchell’s Zebra (Equus Burchelli) at Ndarakwai Ranch Correlate to Frequencies of Other Behaviors." (2010). Independent Study Project (ISP) Collection. 899.