Science / Medicine : Stress Causes Animal Ulcers

Stress can cause ulcers in animals, too.

Gawking crowds were the main reason why four dolphins at the National Aquarium in Baltimore developed stomach ulcers less than two months after being put on display in 1981, researchers reported last week.

In a study to be published by the National Agricultural Library’s animal welfare information center, Dr. Michael Stoskopf of Johns Hopkins University said his research shows that light and noise did not appear to play a major role in the dolphins’ illness, as had been speculated.

“The real problem with the exhibit was the people,” said Stoskopf, who looked at the relationship between about 25 dolphin activities and 15 behaviors of human spectators.

The study found the more people present--and the closer they stood to the dolphin pool--the more often the dolphins engaged in repetitive behaviors, such as standing on their tails, indicative of stress.

The aversion to human scrutiny drove the bottlenose dolphins to spend 87% of their time in pool regions farthest away from spectators. But Stoskopf said no area of the indoor pool enabled dolphins to get far enough away.