How can animals in captivity live better? Give them choices, researcher finds

Exercised or not, providing options lowers animals’ stress and improves behaviors

Give animals in captivity choices in food, whether to spend time inside or out, to be with others or alone, and their general welfare improves—even if they don’t choose new options—a PhD student at Case Western Reserve University has found.

Laura Kurtycz, who had previously studied choices among great apes at Lincoln Park Zoo in Chicago, observed that gorillas and chimpanzees didn’t take advantage of new outdoor spaces as much as the staff had expected. The animals, however, showed less anxiety and tended toward more natural behavior just having the space available.

Studies show that a variety of animals, not just humans, suffer when their ability to choose for themselves is limited or non-existent, she wrote in the magazine The Psychologist, published by the British Psychological Society, late last year.

The findings support growing efforts by zoos to provide environments, diets and other measures that will increase the animals’ health.

“Choices are extremely important for animals in captivity, but this shouldn’t be surprising,” Kurtycz said. “We know how important choices are in our own lives.”

People recognize that domestic animals also have the need to choose. “We provide doggie doors to allow pets to decide when to go out and in,” she said.

Her Lincoln Park Zoo study, published in 2014, is among a growing number to show how choice benefits animals kept from the wild.

Earlier studies have shown that animals have preferences and will act on them when given the option. For example, chimpanzees will exert more effort in a task or walk a greater distance for favored foods.

Laboratory-housed mice generally prefer greater space and work harder to obtain it, while captive European starlings prefer areas lit by fluorescent lights that flicker more frequently and will gather there.

Other studies show simply having choice—even when not exercised—reduced stress, increased sociability in social animals and more.

Giant pandas and polar bears, which were kept in outside enclosures, were less agitated and stressed when they had the choice to enter a room away from the public, even when they remained outside. The bears were noticeably more social and paced less.

In the two-year Lincoln Park Zoo study, chimpanzees given the option to go outside on days when the temperature ranged from 30 to 80 degrees Fahrenheit showed an increase in grooming and other positive social behavior, though they remained mostly indoors.

Gorillas offered a more subtle response on those days. They became less active, which can be interpreted that they were calmer and not as restless, though they were much less likely to go outside, Kurtycz said.

In another study of choice, laboratory-housed marmosets, a South American monkey, showed a significant increase in calm activity patterns when they were able to turn the lights on and off in their cages.

“Choices can mean different things: food, social choices, environment and space,” Kurtycz said. “By offering some choices, we may be able to return some control to animals kept in captivity and increase their well-being.”

Kurtycz hopes to expand her research by studying choice with gorillas and orangutans at the Cleveland Metroparks Zoo as early as this fall.