Behavioral instability is a new concept used for indicating environmental stress based on behavioral traits. This study investigates the possibility of using behavioral instability as a tool for assessing personality in captive animals. The understanding of personality in captive animals can be a resourceful tool in the development of enrichment programs in order to improve animal welfare. In this study it is examined how an olfactory stimulus affects the behavior of two individuals of the species Ursus maritimus in captivity. When using continuous focal sampling throughout the day it was for many behaviors found that the individuals responded differently to stimuli, indicating that there was a difference in personality. This is shown using multiple approaches. One approach used traditional methods for behavioral analyses and the other approach used the concept of behavioral instability as a new quantitative method. This study proves use of behavioral instability as a new quantitative method for investigating personality, expanding the possibility of comparing personality between species. Moreover, it is shown that outliers, which cause asymmetric distributions, should not be removed in behavioral analysis without careful consideration.