The Cetacean Welfare Study is the largest-ever, multi-institutional study of how physical habitat, environmental enrichment, and animal training impact the welfare of cetaceans in zoos and aquariums worldwide. From 2018 through 2019, and from Chicago to Singapore, scientists gathered data from 216 common and Indo-Pacific bottlenose dolphins, 13 Beluga whales, and 8 Pacific white-sided dolphins across 43 accredited facilities in seven countries.

Brookfield Zoo Chicago was a lead investigator, alongside the University of California – Irvine and the University of Florida College of Veterinary Medicine.

“This study exemplifies the collective commitment and effort of accredited zoos and aquariums to continuously improve animal welfare, the number one priority at each of our organizations,” said Lance Miller, Ph.D., vice president of conservation science and animal welfare research for CZS and one of the study’s principal investigators. “The findings from this study provide us with new, science-based best practices and provides ways to approach our cetacean programming.

What did we learn?

Factors like the type and timing of enrichment, social management, and time of training activities were more strongly related to behaviors likely indicative of positive welfare than habitat characteristics (i.e., water volume or depth)
Behavioral diversity can be thought of as an animal’s display of frequent and varied species-specific behavior. It may be a positive indicator of animal welfare for bottlenose dolphins and is a promising metric that may be helpful in monitoring animals to ensure they are thriving.
Features of environmental enrichment programs such as the schedule and how often dolphins received new enrichment were related to positive social interactions, habitat use, and activity levels.
This suggests enrichment programs in accredited zoos and aquariums are important to the welfare of the bottlenose dolphins.

What does this mean for Brookfield Zoo Chicago?
The Zoo is continuing to enhance its existing, robust enrichment program. A member of the marine mammal care team is assigned to provide the dolphins multiple enrichment activities focused on innovation throughout the day to increase the frequency of challenging opportunities. Dolphins engage in foraging exercises, cognitive puzzles, play behaviors, and novel items.
The study’s direct creation of the iOS app ZooPhysioTrak will aid our veterinarians and cetacean managers in checking health and welfare biomarkers of animals at Brookfield Zoo Chicago against the study’s healthy population. This unique tool has reference intervals and values for common and novel indicators of health and welfare for four species of cetaceans—common bottlenose dolphins, Indo-Pacific bottlenose dolphins, beluga whales, and Pacific white-sided dolphins. This application can be used to determine if an individual animal’s values are currently within the range of healthy normal values.
Newly collected data and results improve knowledge and will guide the Zoo’s future animal welfare research.

Review the full study and manuscripts published in PLOS ONE by clicking here.

Funding for this project was provided through a National Leadership Grant from the Institute of Museum and Library Services (IMLS), Grant #MG-30-17-0006-17, with additional support from partner facilities.