Preference assessments as a tool to evaluate environmental enrichment

Environmental enrichment is an important tool utilized to improve animal welfare in zoological institutions through opportunity for mental and physical stimulation. Many past studies have focused on the impact enrichment has on animal behavior; however, none have conducted preference assessments on enrichment items to examine the relationship between animals' preferences and interaction with enrichment over a 24-hr period. Ten-minute free operant, paired-choice preference assessments were implemented in Study 1 to determine the enrichment preferences of African lions (N = 3). Following Study 1, Study 2 was conducted, which examined the behavior of African lions with enrichment items over the course of 30, 24-hr trials to evaluate the relationship between preferences established in Study 1 and long-term interaction with the enrichment. Generalized estimating equations revealed a statistically significant relationship between the percentage of time the enrichment was approached first and the average duration of interaction in Study 1 to the total duration of interaction and the percent of hours interacted with the item in Study 2. Additionally, the first 2 min of the preference data resulted in comparable statistically significant findings, demonstrating shorter preference assessments can produce similar results. The results support our prediction that preference assessments can be used to estimate the amount of interaction with enrichment over the course of time, with preferred items being interacted with more frequently and in longer duration. Information gained from this study suggests preference assessments can be a time and cost-effective tool to evaluate enrichment preference and predicted efficacy.