Zoo scientist observing a plains zebra in exhibit

Animal Welfare Science Program

Zoo scientist observing a pygmy hippo in exhibit

Lincoln Park Zoo uses science to improve the welfare, or quality of life, of animals in human care. The Animal Welfare Science Program continually evaluates and enhances animal welfare by asking and answering questions that directly impact quality of life for zoo animals. Its experts regularly share animal welfare science through presentations and publications, provide training to young scientists, and work with the larger zoo community to broaden the impact of their research.

What Is Animal Welfare?

Animal welfare, generally speaking, refers to an individual animal’s quality of life. While care is something humans provide to animals, welfare is what each animal is experiencing internally.


What Impacts Animal Welfare?

Many aspects of an animal’s world can impact welfare, including physical health, social interactions, exposure to light and sound, relationships with animal keepers, and the degree to which the animal feels in control of its habitat. What’s more, the welfare of different animals can vary even when experiencing the same care, depending, for example, on their history or temperament.


Inforgraphic explaining the relationship between animal care and animal welfare. Care is provided via animal management, enrichment, nutrition, positive reinforcement training, and veterinary services. Welfare is measured via behavior, habitat use, hormones, and other measurables.

How It Works



Animal welfare scientists use an ever-expanding toolbox to evaluate welfare. One of their primary tools is ZooMonitor, a behavioral-monitoring app developed by Lincoln Park Zoo scientists. Each day, a large team of trained volunteers and interns uses this app to systematically gather information about the behavior and habitat use of zoo animals. Welfare scientists and Animal Care staff then review this information to infer welfare and inform strategies for enhancing it.

The Animal Welfare Science Program also uses a number of other innovative tools. For example, by non-invasively measuring hormones in collaboration with the zoo’s Davee Center for Epidemiology, welfare scientists can determine how much stress each animal is experiencing internally. And by using motion-activated cameras and remote sensors, they can learn how each animal uses its habitat when humans aren’t around.



Once they have gotten some measure of an animal’s welfare, they try to enhance it. Zoo experts use many techniques to enhance animal welfare, including enrichment strategies and habitat modifications. After implementing a new approach, they again evaluate welfare to determine whether the changes were effective. This cycle repeats indefinitely as they continually work to raise the bar and respond to each animal’s changing needs and preferences.


  • Wark, J.D. (2022) Power up: Combining behavior monitoring software with business intelligence tools to enhance proactive animal welfare reporting. Animals, 12, 1606. https://doi.org/10.3390/ani12131606.
  • Wark, J.D., Schook, M.W., Dennis, P.M., Lukas, K.E. (2022) Do zoo animals use off-exhibit areas to avoid noise? A case study exploring the influence of sound on the behavior, physiology, and space use of two pied tamarins (Saguinus bicolor). American Journal of Primatology. https://doi.org/10.1002/ajp.23421.
  • Cronin, K.A., Leahy, M., Ross, S.R., Schook, M. W., Ferrie, G., & Alba, A. (2022). Younger generations are more interested than older generations in having non-domesticated animals as pets. PLOS One. 17(1): e0262208.
  • Ramont, M., Leahy, M., & Cronin, K.A. (2021). The welfare of domestic goats (Capra hircus) in a zoo-based animal-visitor interaction program. Animal Behavior and Cognition. 8(4), 493-506.
  • Doelling, C. R., Cronin, K. A., Ross, S. R., & Hopper, L. M. (2021). The relationship between personality, season, and wounding receipt in zoo‐housed Japanese macaques (Macaca fuscata): A multi‐institutional study. American Journal of Primatology, e23332.
  • Cronin, K.A. (2021). Working to supply the demand: Recent advances in the science of zoo animal welfare. (Editorial). Journal of Zoological and Botanical Gardens, 2(3), 349-350.
  • Wark, J.D., Wierzal, N.K., Cronin, K.A. (2021) Gaps in live inter-observer reliability testing of animal behavior: A retrospective analysis and path forward. Journal of Zoological and Botanical Gardens. 2(2):207-221. https://doi.org/10.3390/jzbg2020014.
  • Cairo-Evans, A., Wierzal, N.K., Wark, J.D., Cronin, K.A. (2021) Do zoo-housed primates retreat from crowds? A simple study of five primate species. American Journal of Primatology.
  • Ramont, M., Leahy, M., & Cronin, K.A. (2021). Domestic animal welfare at the zoo: The impact of an animal visitor interaction program on chickens. Animal Behavior and Cognition, 8(1), 1-14.
  • Woody, S.M., Santymire, R.M. & Cronin, K.A. (2021). Posture as a non-invasive indicator of arousal in American toads (Anaxyrus americanus). Journal of Zoological and Botanical Gardens. 2: 1-9.
  • Cronin, K.A. & Hopper, L.M. (2020). Do monkeys care what’s fair? Frontiers for Young Minds. 8: 550299.
  • Cronin, K.A. & Ross, S.R. (2020). When is “natural” better? The welfare implications of limiting reproduction in captive chimpanzees. In L.M. Hopper & S.R. Ross (Eds.), Chimpanzees in Context, University of Chicago Press. pp. 509-523.
  • Cronin, K.A., Martens, A., Ness, T., Leahy, M., & Ross, S.R. (2020). Sex and season predict wounds in zoo-housed Japanese macaques (Macaca mulatta): A multi-institutional study. Zoo Biology, 39: 147-155.
  • Binding, S., Farmer, H., Krusin, L., & Cronin, K.A. (2020). The status of welfare research in zoos and aquariums: Where are we, where to next? Journal of Zoo and Aquarium Research, 8(3): 166-174.
  • Wark, J. D., Wierzal, N. K., & Cronin, K. A. (2020). Mapping shade availability and use in zoo environments: A tool for evaluating thermal comfort. Animals, 10(7), 1189. doi:10.3390/ani10071189.
  • Woods, J.M., Ross, S.R.. & Cronin, K.A. (2019). The social rank of zoo-housed Japanese macaques is a predictor of visitor-directed aggression. Animals, 9: 316-325.
  • Saiyed, S.T., Hopper, L.M. & Cronin, K.A. (2019). Evaluating the behavior and temperament of African penguins in a non-contact animal encounter program. Animals, 9: 326-339.
  • Wark, J. D., Cronin, K. A., Niemann, T., Shender, M. A., Horrigan, A., Kao, A., & Ross, M. R. 2019. Monitoring the Behavior and Habitat Use of Animals to Enhance Welfare using the ZooMonitor App. Animal Behavior and Cognition, 6(3), 158–167. https://doi.org/10.26451/abc.
  • Cronin, K.A. & Ross, S.R. (2019). Technical contribution: A cautionary note on the use of behavioural diversity (H-Index) in animal welfare science. Animal Welfare, 28: 157-164.
  • Jacobson, S., Kwiatt, A., Ross, S.R. & Cronin, K.A. (2019). The effects of cognitive testing on the welfare of zoo-housed Japanese macaques (Macaca fuscata). Applied Animal Behaviour Science, 212: 90-97.
  • Hopper, L.M., Cronin, K.A. & Ross, S.R. (2018). A multi-institutional assessment of a short-form personality questionnaire for use with macaques. Zoo Biology, 37: 281-289.
  • Cronin, K.A., Bethell, E.J., Jacobson, S.L., Egelkamp, C., Hopper, L.M., & Ross, S.R. (2018). Evaluating mood changes in response to anthropogenic noise with a response-slowing task in three species of zoo-housed primates. Animal Behavior and Cognition, 5: 209-221.
  • Cronin K.A., Jacobson S.L., Bonnie K.E., & Hopper L.M. (2017) Studying primate cognition in a social setting to improve validity and welfare: a literature review highlighting successful approaches. PeerJ 5:e3649.
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