After Mule Deer Decline, Human Collaboration Could Bring Herd Back

Mar 30, 2018

For the last 20 years, the Wyoming Range mule deer herd has been in decline, and nobody has been quite sure why. But five years ago a collaborative effort began to radio collar deer, giving scientists a chance to get a closer look at what’s threatening the herd. The research points to disease, predators, and vehicle collisions, to name a few. But the most important variable that’s emerged from the research is habitat loss, which is most evident in the herd’s winter range.

The land is a patchwork of state, federal and private land stretching between Kemmerer and the Utah border. This rugged hilly terrain is covered in sagebrush. Other than that, it’s dirt roads and well pads, and scientists say the presence of energy development is what’s negatively impacting the herd. Now, the Wyoming Mule Deer Project is closely tracking deer behavior in the hopes of contributing to a conversation about smart development that will help both energy and mule deer thrive in western Wyoming.

The Wyoming Mule Deer Project captures the deer they study twice a year, to check on their physical condition and to replace their collars. After seeing them in action at spring capture, the easiest way to describe this process is: NASCAR pit crew. They’re swift, but much more tender with the deer then you’d be with a race car.

First, the deer are located using GPS coordinates transmitted from their radio collars. Then a helicopter crew captures and transports them to a field lab, where a team of scientists and volunteers are ready to spring into action.

The deer arrive blindfolded to keep them calm, and their legs are bound so they can’t kick anyone. University of Wyoming research scientist Sam Dwinnell kneeled on the ground to cradle the head of a deer in her hands.

“It’s 88,” Dwinnell told the rest of the team. “She goes way up to the Greys River.”

Each deer in the study gets their own individual number, and when Dwinnell recognized deer 88, she began to piece together her story. Dwinnell knows where she winters, where she summers and how she migrates from data collected from her collar.

The batteries only last so long, so Dwinnel is giving 88 a new collar. While she did that, the team checked 88’s percent body fat and to see if she was pregnant. She was, so they inserted a transmitter into her birth canal, so they’ll know if and when her fawn is born. Then they weighed her, drew blood, collected a fecal sample, took her temperature, and measured her oxygen saturation and pulse.  

Since 2013, Dwinnell has coordinated the collaring of more than 370 deer. The goal is to keep collars on 70 adult does, and as many fawns as possible. As deer die, she replenishes the sample size by capturing more deer.

Dwinnell said five years of research shows that habitat is what drives the trajectory of mule deer populations in Wyoming, and the presence of oil and gas infrastructure on the winter ranges doesn’t help because that’s where deer go to feed when the mountains are covered in snow.

“So when energy development occurs in those areas, you not only get direct habitat loss where roads are developed and where well pads are developed,” Dwinnell said, “but you also get indirect habitat loss where animals are responding in their behavior in that they are avoiding these areas.”

That means the animals are stressed and eating less, which impacts their ability to carry fawns to term and makes them more susceptible to disease. The evidence is strong, but Dwinnell is sympathetic to the resistance some folks have to her findings.

“This research is happening in these communities that really depend on oil and gas development; it’s how a lot of people survive.”

Dwinnell is hoping her research can help bring about smarter development, because she knows these communities love their mule deer.

“They’re very connected to the landscape through hunting and through recreation in those communities,” said Dwinnell. “It’s just two things that they value, and so there’s always going to be a compromise, but there are ways of considering mule deer populations while still developing those areas.”

Dwinnell did a close study of where and how mule deer consume sagebrush in proximity to well pads, pipelines and roads, and she’s researched ways development can mitigate habitat loss.

This winter, she did a series of public talks to help share that information.

“And it’s always interesting — the energy development aspects of my research are what people have the most skepticism for,” said Dwinnell.

Gary Fralick helps the Wyoming Mule Deer Project get the word out about the health of the state’s herd. As a biologist with the Wyoming Game and Fish Department, he said the project’s long-term approach has provided knowledge that never existed before, and the public has been open to making changes.

“For example, what type of hunting seasons do we design, where do we target specific sections of highway to minimize vehicle collisions, how do we use the landscape or not use the landscape in some areas that we know are crucial areas?” said Fralick.

Several years ago, newborn fawns were dying at high numbers. The project was able to test and confirm it was the adenovirus, a disease passed between deer when they end up in close quarters, like when people feed them. It may be hard to get people to make changes to the way energy development is handled, but Fralick said it wasn’t so hard with the adenovirus.

“We were able to convey that information to the public and working cooperatively passed regulations and rules that would prohibit people from providing supplemental feed.”

Shauna Ridgeway, whose husband works in the oil fields, said the research on energy development is still young, but she sees an openness to the Wyoming Mule Deer Project’s recommendations about how to operate in mule deer country. Ridgeway said when she talks to her husband’s co-workers they share her concern for how the industry is affecting the deer. Apparently, Ridgeway talks about this a lot.

“I kind have been dubbed the crazy deer lady in Kemmerer.”  

Her more official title is chair of the Kemmerer Muley Fanatics chapter, one of the collaborating organizations that make this research possible.

“It used to be you could go out for an afternoon drive and see hundreds. And now you’re lucky if you see a handful of them.”

Ridgeway said without conservation efforts, she’s concerned her two kids won’t get the chance to hunt mule deer, let alone easily see them in the wild.

“So I’m doing my part to make sure they can do that.”

Ridgeway said she’s hopeful they’ll be able to keep the herd healthy as long as scientific research and a spirit of collaboration continues.

Back at captures, Dwinnell and her crew released deer 88. She pranced off into the sagebrush.

It’s only goodbye for now. If all goes according to plan, the Wyoming Mule Deer Project will see her and her healthy newborn fawn this summer.