Quantifying happiness: Animal welfare science

March 6, 2015 - 10:42am

Oregon Zoo researchers are helping to establish measures of well-being for animals

At a newly remodeled space inside a former Oregon Zoo animal clinic, a small group of researchers and volunteers is attempting to identify what makes life worth living.

Led by Dr. Nadja Wielebnowski, the zoo's conservation and research manager, this team is working to establish a set of tools and measures to help staff assess the well-being of the animals in their care.

"Our research team is working to establish a number of indicators that collectively tell us what an animal is experiencing."

—Dr. Nadja Wielebnowski, conservation and research manager

"Animals can't tell us what they are feeling," Wielebnowski said. "But they do communicate their needs in a variety of ways. Our research team is working to establish a number of indicators that collectively tell us what an animal is experiencing and provide us with a way to assess an animal's overall quality of life."

The project got a boost earlier this year with the hiring of a dedicated staff member, Dr. Candace Scarlata, a position made possible by a grant from the Oregon Zoo Foundation. In addition to funding Scarlata's position, the foundation helped equip the new lab to allow for more advanced monitoring of hormone levels — one indicator of an animal's well-being.

Hormones are chemical messengers in the bloodstream and tissues that trigger a wide variety of processes in the body. Some — such as glucocorticoids, or "stress hormones" — can provide insight into an animal's psychological state. Tracking the levels of glucocorticoids over time and under varied circumstances helps reveal how an animal is responding to its surroundings and activities.

Stress, Wielebnowski points out, is not inherently bad.

"Some stressful activities, such as introductions to other animals or mating, are stimulating and challenging in a good way," Wielebnowski said. "We need to interpret our data carefully and use multiple measures to understand when good stimulating stressors become negative stressors that may result in distress or chronic stress."

The Oregon Zoo has monitored reproductive hormones such as testosterone and progesterone in its elephant family weekly for more than 25 years, longer than any other zoo in North America. This bank of data has led to a deeper knowledge of elephant breeding and gestation as well as male musth cycles, which helps animal-care staff better understand and meet the needs of both individual elephants and the herd. Published widely in scientific journals, the zoo's findings have informed Asian elephant management worldwide.

Wielebnowski, Scarlata and their team will soon begin monitoring a wider variety of hormones including glucocorticoids. Coupled with physical health and behavior observations, the hormone data is expected to provide animal-care staff with a more well-rounded understanding of each animal's physical and mental well-being.

"Each animal has a unique history and set of life experiences," Wielebnowski said. "We can establish the basic standards of care for every animal but we still need to adapt the setting and daily routine to the needs of each animal. Regular hormone and behavior monitoring can help us establish some of these needs."