Table 1.
Independent variables tested for association with stereotypic behavior rates.
Table 2.
Ethogram.
Fig 1.
Median Day and Nighttime active behavior percentages.
Asterisks represent significant period differences (p<0.05). In the Daytime and Nighttime, median values for Other and Social Contact were zero. The median value for Feed & Locomotion was also zero during the Nighttime.
Fig 2.
Median daytime active behavioral observation percentages and interquartile ranges.
Asterisks represent significant species differences (p<0.05). For the full population, African and Asian elephants, the median values for Other were zero. The median values for Social Contact were also zero in full population and African elephants.
Fig 3.
Median daytime active behavioral observation percentages and interquartile ranges.
Asterisks represent significant sex differences (p<0.05). For the full population, males and females, the median values for Other and Social Contact were zero.
Fig 4.
Median nighttime active behavioral observation percentages and interquartile ranges.
Asterisks represent significant species differences (p<0.05). For the full population, median values for Feeding & Locomotion, Other, Self-Maintenance, and Social Contact were zero. For African elephants, median values for Other, Self-Maintenance, Social Contact, and Stereotypic Behavior were zero. For African elephants, median values for Feeding & Locomotion, Other, and Social Contact were zero.
Fig 5.
Daytime stereotypic behavior performance rates calculated as a percentage of active time for individual elephants.
The average stereotypic behavior rate in the full population was 15.5%, the min 0.5%, and the max 68.1%.
Fig 6.
Nighttime stereotypic behavior performance rates calculated as a percentage of active time for individual elephants.
The average stereotypic behavior rate in the full population was 24.8%, the min 1.4%, and the max 74.2%.
Fig 7.
Risk increase for stereotypic behavior rate by Percent Time Housed Separately for African and Asian elephants: Percent Time with Juveniles, Percent Time Managed, and Transfers are all held constant at the average levels (13.0%, 54.1%, and 3.3 respectively).
Values on the X-axis reflect the range of Percent Time Housed Separately scores seen within our sample population.
Fig 8.
Risk increase for stereotypic behavior rate by Percent Time with Juveniles for African and Asian elephants: Percent Time Housed Separately, Percent Time Managed, and Transfers are all held constant at the average levels (22.3%, 54.1%, and 3.3 respectively).
Values on the X-axis reflect the range of Percent Time with Juveniles scores seen within our sample population.
Fig 9.
Risk increase for stereotypic behavior rate by Percent Time Managed for African and Asian elephants: Percent Time Housed Separately, Percent Time with Juveniles, and Transfers are all held constant at the average levels (22.3%, 13.0%, and 3.3 respectively).
Values on the X-axis reflect the range of Percent Time Managed scores seen within our sample population.
Fig 10.
Risk increase for stereotypic behavior rate by Transfers for African and Asian elephants: Percent Time Housed Separately, Percent Time with Juveniles, and Percent Time Managed, and Transfers are all held constant at the average levels (22.3%, 13.0%, and 54.1% respectively).
Values on the X-axis reflect the range of Transfers scores seen within our sample population.
Table 3.
Independent variables tested for association with daytime stereotypic behavior rates and statistics associated with the univariate negative binomial regression models.
Table 4.
Daytime model for variables associated with stereotypic behavior rate risk (N = 154, QIC = -8481).
Table 5.
Descriptive statistics for variables in the daytime model.
Fig 11.
Risk increase for stereotypic behavior rate by Social Experience for African and Asian elephants: Percent Time with In/Out Choice, and Transfers are both held constant at the average levels (31.7% and 3.2 respectively).
Values on the X-axis reflect the range of Social Experience scores seen within our sample population.
Fig 12.
Risk increase for stereotypic behavior rate by Percent Time In/Out Choice for African and Asian elephants: Social Experience and Transfers are all held constant at the average levels (2.7 and 3.2 respectively).
Values on the X-axis reflect the range of Percent Time In/Out Choice scores seen within our sample population.
Fig 13.
Risk increase for stereotypic behavior rate by Transfers for African and Asian elephants: Social Experience and Percent Time In/Out Choice are all held constant at the average levels (2.7 and 31.7% respectively).
Values on the X-axis reflect the range of Transfers scores seen within our sample population.
Table 6.
Independent variables tested for association with nighttime stereotypic behavior rates and statistics associated with the univariate negative binomial regression models.
Table 7.
Nighttime model describing variables associated with stereotypic behavior rate risk (N = 32, QIC = -2358).
Table 8.
Descriptive statistics for variables in the nighttime model.
Table 9.
Comparison of significant independent variables between the sub-population in our study (N = 89 daytime, N = 32 nighttime) and the adult North American zoo elephant population (N = 217).