Counting Sheep

Counting Sheep
Tracking wildlife across far-flung landscapes

An alarm clock trips at 3 AM in the cold California desert.

With a wide-brimmed hat capping shoulder-length hair, Clint Epps hikes through darkness into the mountains to a water hole where wildlife gather. By dawn, he's hidden in scant shade against the coming 110-degree heat.

A herd of desert bighorn sheep wanders over for a drink. Epps sits perfectly still. Sweat runs into his eyes and cakes his binoculars. “I can hide from sheep but not the heat,” he said later. “Ultimately you have to come to peace with the heat.”

Epps is a bighorn paparazzo, tracking the sheep throughout their range to learn how changes to the landscape are changing the population dynamics of migratory wildlife. As the stocky bighorns amble away, Epps scoops up a handful of black pellets and lifts them to his nose. These are the best kind: fresh and packed with DNA.

[caption caption="OSU wildlife ecologist Clint Epps has worked in Tanzania for several years, investigating how large mammals disperse across the landscape. Shown here holding the skull of a giraffe, Epps uses DNA from giraffe feces to track gene flow among giraffe populations across Tanzania. (Photo by Rachel Crowhurst.)"]Clint Epps[/caption]

Epps uses DNA to map how genes are shared among animals whose habitats are increasingly carved up by roads, construction, and energy projects. Desert bighorn usually band together in small herds of 10 to 20 sheep. When these small herds are isolated from each other, they share less DNA, the gene pool shrinks, and inbreeding sets in. Coupled with harmful effects from climate change—like drought, scant forage, and excessive heat—these sheep are staring down an uncertain future.

“They’re walking a knife edge, especially during drought years,” Epps said. “First, the lambs suffer, then fail. The adults muddle through until they hit a breaking point; then we see piles of dead sheep scattered around dry water holes. Any animal that makes a living in this terrain has grit and deserves respect. Some of these places look like the back side of the moon.”

Of the more than 80 populations of desert bighorn that have lived in California since the early 1900s, more than a third have experienced local extinctions. Epps is quick to point out that some populations have been restored through reintroduction or natural recolonization, which suggests the ability of bighorns to maintain stability across populations. Epps uses genetic evidence to show that human activities have isolated populations and contributed to their decline. When habitats don’t connect, sheep can’t find each other to breed. Divergent patterns of DNA among separated groups show a shallower gene pool, potentially making sheep more prone to disease and inbreeding. The smaller each population shrinks, the more vulnerable they all become.

New developments in the Mojave Desert could make the sheep’s plight worse. The U.S. National Park Service has considered renewable energy projects, such as solar power plants, on land used by desert bighorn. Epps’ research showed that swathes of habitat could be lost, and there are concerns that the construction process—with trucks, noise, lights, and staging areas—would create even more obstacles for the few remaining herds of bighorn.

In this and other land-use planning, Epps presents his recommendations for protecting wildlife habitat based on scientific research; but the ultimate decisions are out of his hands. “My job is to provide people with better information,” he said.

Epps actually has many jobs at Oregon State University. One day he’s a wildlife ecologist; the next, a conservation biologist; then, a professor in the College of Agricultural Sciences. He’s studied threatened species throughout the American West and East Africa. A common effort in all his work is to establish a baseline count of animals.

“Conversations about conservation begin when we step back and see what is actually left,” Epps said. “There’s a tendency to think that everything was wilderness until just recently. But there have been people on the African landscape ever since there have been people. We’ve influenced wildlife since the beginning of our existence.”

[caption caption="Elephants move long distances between protected areas in Tanzania. Epps fears that rapid development and intense levels of poaching have disrupted their movement across the landscape. (Photo courtesy of Clint Epps.)"]elephant[/caption]

Epps spent 2 years trekking around East Africa observing how booming human populations and agricultural growth have affected wildlife species. Epps found that hyenas, antelope, elephants, and other mammals still move freely in a few places between fenceless wildlife reserves, but corridors are disappearing fast. His research showed how paths of frequent elephant travel are also used by other wildlife. Protecting these routes could help conserve many threatened species, he argued.

However, not long after Epps’ last major field work in Africa in 2009, an outbreak in poaching killed nearly 100,000 African elephants in 2 years.

“You work for years and see elephants surviving in the pocket of space we’ve managed to leave for them. Then there’s this huge spike in poaching and everything changes,” said Epps. “If officials can be paid to look the other way, bad things can happen. But I tell students, it’s important to be optimistic if we want to make any progress at all.”

While Epps has spent years in the field, often alone, he makes a point to learn about the values that people and cultures bring to the conservation table. He believes that more areas of the world would be receptive to conservation if locals felt their concerns were heard. For example, where African habitat and farms overlap, elephants can kill people and destroy crops. Some of the indigenous people Epps has worked with regularly eat species such as macaws and monkeys that most Americans regard as objects of conservation.

[caption caption="A different kind of wildlife? Clint Epps plays bluegrass guitar. Watch the video."]bluegrass band[/caption]

“I ask people, ‘What’s life like for you?’” he says. “Some people interact with wildlife in a totally different way than we do. We had better recognize that or else everybody stands around, calling each other idiots, getting nowhere.”

“Still,” he says, “I believe we have a duty to conserve wildlife. We have to be clear about our own values.” Epps’ values compel him to learn what disconnects animals from each other and their homes. It’s why he counts sheep in the middle of the night and isn’t scared away by predators, poachers, or heat exhaustion.

Out in the field, sopped with sweat and sunscreen, Epps says he feels most like himself. It gives him “unfettered time to think,” to ponder how humans can learn to share the landscape with wildlife. “There are moments when I’m hot, dusty, covered in flies, and frustrated with mankind—and then a giraffe walks by. And I think, ‘It’s all worth it.’”

Published in: Ecosystems, People