The Dung Decoders

Gutsy Research Going on at WSU Wildlife Nutrition Habitat Lab

Caribou
Caribou

When Canadian scientists literally stepped in 8,000-year-old caribou dung, there first thought wasn’t, Yuck, but, What a treasure trove!

The dung was exposed as a glacier melted in Canada’s Yukon Territory along with a valuable collection of other biological material. As reported in a 2002 article in Science, large mammals, freeze-dried birds and rodents, and human artifacts were found in the melting glacier.

And when the Canadian scientists wanted to know what caribou were eating 8,000 years ago, they turned to Washington State University’s Wildlife Habitat Nutrition Lab to have the ancient dung analyzed.

“They sent us fecal pellets to see what they were eating and to compare that with present day herds,” Wildlife Habitat Nutrition Lab manager Bruce Davitt said. “The amounts found were similar to a typical spring or summer diet.”

Bruce Davitt - photo by Brian Charles Clark
Bruce Davitt

The fecal pellets had been preserved in ice patches where, researchers suspect, the caribou paused to cool off during the spring and summer months. Because artifacts were found alongside the remains, the ice patches are believed to have been hunting grounds for native peoples.

The lab serves the scientific community on a wide variety of projects. “We have worked with about ninety universities, biologists in almost every state and Canadian Province, and on projects in about thirty foreign countries,” Davitt said. “In a lot of the projects, as with the ancient caribou, we’re just one part of the bigger picture,” he said.

But on at least one occasion, the lab was front and center in a forensic investigation.

A number of zoos have reached out to Davitt and the lab for gut content analyses after a discovery the lab made when working with the Bronx Zoo. The sudden deaths of two silver-leaf langurs at the zoo prompted an investigation into the gut contents of the monkeys.

Silver-leaf langurs
Silver-leaf langurs

“Originally the zoo thought the monkeys were eating the rope at the zoo and that it was damaging their gut. What we found is that a decorative plant, pandanus, was being consumed by monkeys of lower social status and who weren’t getting as much food as others,” Davitt said. Pandanus is a genus of plants common in the tropics, the native habitat of langurs.

After studying the pandanus found in the gut contents, the lab found that parts of the plant have a sandpaper-like quality that scrapped away the monkeys’ intestines, causing fatal damage. This discovery led to similar investigations at the Philadelphia Zoo, South Carolina Zoo, and elsewhere.

Gut contents of 13,000-year-old wooly mammoth frozen in Alaska, diets of feral goats found on an island east of Madagascar from the pirate era, post-eruption diets of elk in the Mt. St. Helens area, and diets of reindeer in Mongolia only begin to list some of the projects the lab has been involved with over the years according to Davitt.

The self sustaining lab is also a core facility for the Department to Natural Resources Sciences in training graduate students in laboratory techniques. As well, the lab is used in support of various undergraduate wildlife ecology course labs while undergraduate researchers gain valuable research experience.

For more information, please visit http://nrs.wsu.edu/research/wildlifehabitat.html.

by Brian Clark and Lyndon Ducuan