KANSAS CITY, Mo. -- Don't tell Dumbo, but he's got too much junk in his trunk. That spherical silhouette, it turns out, isn't so healthy -- even for elephants.
Zookeepers have long suspected it. And now they have some science to back it up.
America's zoo elephants have gotten fat.
"Look at what percentage of the U.S. population is currently obese. Are we surprised that we're feeding our elephants a little too well?" said Anne Baker, former director of the Toledo Zoo. "We're feeding ourselves a little too well."
This fall, zoo researchers from across the country are wrapping up the biggest study of zoo elephant health in the nation's history. And they've uncovered a range of major findings, from the health of elephant feet, to the miles they walk, to the prominence of their posteriors.
Over three years, the team examined more than 100,000 pages of medical records, 6,000 blood samples and 40,000 pounds of elephant dung. Subjects included 255 elephants in 70 zoos from Mexico to St. Louis to Miami.
Researchers hope to submit the study to scientific journals for publication as soon as this winter. But even preliminary findings, they said, are revealing.
Keepers and activists have long worried about elephant foot and joint problems, attributed to hours spent on hard concrete and stone. But researchers counted 75 percent of the elephants in this study without joint problems, as well as a noticeable decline in foot issues since 2011. Zookeepers figured an increased use of grass, rubber and sand flooring in elephant pens has helped.
"This is really good news," Jill Mellen, a scientist at Disney's Animal Kingdom, told zoo professionals at the Association of Zoos & Aquariums' annual conference last month in Kansas City. "This is cause to celebrate."
In addition, elephants in the study walked more than some believed -- about 5.8 km on average a day, up to a maximum of about 17.7 km. That, said Cheryl Meehan, an animal welfare scientist and the study's project manager, stacks up well against distances documented in recent studies of walking among wild elephants.
The study also unveiled a few concerns. Two-thirds of the animals studied, for instance, behaved in repetitive manners, such as swaying or pacing, which are often considered signs of mental or physical stress.
But it's the study of elephant weight that has, so far, gathered the lion's share of attention.
Researchers evaluated 240 elephants for body conditions. "It started by looking at a lot of elephant butts," Kari Morfeld, a postdoctoral scholar at the Smithsonian Conservation Biology Institute, told conference attendees in Kansas City.
Just four percent were tagged as too skinny. Nearly three-quarters of the elephants were squarely overweight.
Researchers point out the issue really isn't funny. Those hefty hineys can lead to, for instance, a decline in female reproductivity -- something zoos monitor quite closely.
Elephants in the wild can ovulate, or "cycle," into their 50s, said Janine Brown, a reproductive physiologist at the Smithsonian. Yet zoo elephant fertility can shut down a decade earlier, Brown said.
-- St. Louis Post-Dispatch