Zookeepers around the world are cutting calories and increasing exercise for animals who can suffer from too much food and too little room to roam. The Fresno zoo embarked on the elephant slimming campaign after getting the ability to weigh them regularly in January 2009.
"We knew they were heavy, but we didn't know just how heavy," said Harold Mountan, the zoo's assistant animal curator.
Zoo officials learned just how large "the girls" were after spending $5,000 to buy an elephant scale. Previously, they had borrowed a truck scale periodically from the California Highway Patrol, Mountan said. Today, zookeepers keep tabs on Shaunzi and Kara with regular weigh-ins and - in addition to changes in their diet - make them work to find food, as their cousins in the wild must do.
To get their food, the elephants must stretch, dig, push, or prod with their trunks or legs. They slam barrels with their trunks to release a few food pellets or reach for hay bags, and they must correctly position the barrels and bags to release the food. They use their trunks to sniff out food beneath the sand.
They also have an exercise regimen, not unlike deep knee bends and stretching for humans, that also improves their mobility, Mountan said.
Enhancing activity and reduced-calorie diets also are being used for other animals at the Fresno zoo, said Scott Barton, zoo director.
"Weight is really important," he said. "We are looking at the factors that cause obesity, the same factors as we do in the human population."
Although the diet and exercise program is relatively new to Chaffee, it's standard in many other places - because in zoos today, thin is in.
There was a time when zoo officials were excited to talk about their large animals, said Harry Peachey, curator of mainland Asia animals at the Columbus Zoo in Ohio.
"If you had an 800-pound gorilla in your collection you would brag about it," he said. "Now, you would be embarrassed to say that in front of your peers."
Studies have found that zoo gorillas had a higher incidence of heart disease, and zookeepers believe it's caused by overly generous diets, Peachey said.
The first elephant weight-loss program began about nine years ago at San Diego Zoo and Wild Animal Park. Jeff Andrews, associate curator for mammals, realized how much thinner elephants appeared in the wild.
Before the weight-loss program, keepers would place food in front of the animals and offer them high-calorie snacks, such as fruit. And the animals got little or no exercise.
Andrews aimed to improve the elephants' health by reducing the amounts they are fed and replacing higher-calorie food with low-cal choices. Elephants also were trained to exercise and allowed to wander their enclosures at night instead of being placed in individual stalls.
It worked. Five elephants lost between 1,500 and 2,000 pounds each and a sixth male dropped 3,500 pounds - about 23 percent of his body weight - Andrews said.
In Frezno, Shaunzi's muscles seemed to be stiffer when she carried more weight, but "they are moving a lot better now," Mountan said. "Their muscles are in better shape."
The elephants also are evaluated on the way parts of their bodies appear as weight is lost. In a rear view of the elephants, Mountan notes how their backbones have become more evident in recent months. He said the backbone must become a bit more pronounced, which means losing a few hundred more pounds.
When the elephants reach their weight goal, the amount of food they get will be adjusted to meet their new, lower-calorie demands.
"The less extra weight older people carry around, the healthier they usually are, and that goes for elephants, too," he said.