Measuring Stress in Wild Species

Non-Invasive Studies of Stress Hormones

Animals experience stress just as people do. New living situations, illness, aging and other life events can cause stress—both good and bad.

But while people can share when they’re experiencing stress, animals are prone to hiding it. Caregivers may observe changes in behavior, but it’s difficult to objectively know if animals are experiencing stress, in zoos and in the wild.

Endocrinologists can measure animal stress, though, using feces, urine, hair, blood or saliva to pinpoint levels of stress-related hormones. Feces offer the advantage of being abundant and non-invasive; they can be collected daily without disturbing wildlife.

By collecting feces from a range of species, zoo scientists are able to establish baseline stress levels—and determine how changes in the animal’s environment, social group or other factors impact stress levels. This information is vital for improving animal care and conservation both at Lincoln Park Zoo and around the globe.