In their past three years of searching, state wildlife biologists have found zero evidence of brucellosis in elk herds in the Bighorn Mountains. And in an effort to increase sample sizes, the state lab has figured out how to include blood samples once considered unusable. That’s the good news.

Yet, research of the disease is hampered by a rate of return of test kits deployed to hunters around the state. The rate of return from harvested elk is about 20%, but many hunters just forget.

“We’ve tried to help them remember through a raffle and constant reminders,” said Eric Maichak, Wyoming Game and Fish Department wildlife disease biologist.

Partnering with the Rocky Mountain Elk Foundation, Vortex, Maven, Leupold and the Wyoming chapter of the Wildlife Society, the Game and Fish raffles off some sweet hunting gear. Hunters are entered into the raffle by returning a blood sample and a completed data card from the blood kit that they received via mail or handout.

It’s part of an effort to “recognize hunter’s contributions to brucellosis monitoring and encourage more participation in the program,” Maichak said. “It takes all of us working together to [collect the data]. We appreciate the current level of involvement, but need more help from hunters.”

Brucellosis is an infectious disease caused by bacteria. The disease causes animals infected to abort their fetuses and can be passed to humans through contact. An eradication effort in the U.S., which began in the 1930s, cost millions of dollars to achieve. While currently under control in the cattle industry, the disease persists in ungulate populations — including elk and bison of the greater Yellowstone ecoystem.

In some hunt areas in the Cody Region, prevalence rates are as high as 25-30%. But until 2012, the disease had not been found in the Bighorns. The department started looking into the spread of the disease as soon as positive results first started showing up.

“Folks were pretty alarmed and we’re trying to take a hard look at how that might have happened,” Maichak said.

The Game and Fish increased the number of test kits sent to hunters in the Bighorns to about 6,500 kits and added seasonal personnel to work with sportsmen and women. But getting hunters to participate is tough.

“Our average return per year has been right around 650 to 700 [kits],” said Maichak.

Finding samples positive for the disease sparked two big projects: increased blood samplings and enhanced surveillance by capturing, testing and collaring elk in the Bighorn range. Working under the theory that elk were moving into the Bighorns by traveling down the lower Greybull River, the department captured and collared 25 elk in the region.

On the Absaroka Front, the intersection of the Wood and Greybull rivers is an important winter range and a hot spot for brucellosis. But what the department found just added to the mystery.

“We haven’t seen any collared elk crossing the Basin,” Maichak said.

The department is responding by attempting to manage Hunt Area 66 — a huge tract encompassing the lower Greybull River — for zero elk. The effort is to slow disease transmission as well as lowering crop depredation; the department pays out more than $1 million per year in crop and livestock losses due to wildlife.

Efforts have been hampered due to the size of the area, which encompasses a lot of private land with plenty of places for elk to hide. The department has attempted to increase harvest by pointing hunters to herds in the area and offering general tags for the species.

One unknown factor is the disease potentially moving into the range across the Montana border.

Meanwhile, in an effort to increase sample sizes, the state lab has figured out how to include blood samples once considered unusable.

A large percentage of tests were coming back previously frozen, which causes the rupture or destruction of red blood cells, called hemolysis. The state wildlife lab in Laramie decided that, due to the low rate of return on test kits, it was worth testing samples previously discarded to increase the chances of detecting the disease.

Wildlife disease biologist Jessica Jennings-Gaines conducted research to determine if frozen blood samples affect results in brucellosis testing.

“We’re able to detect the antibodies at the same level as if they were really good samples,” Jennings-Gaines said. “You can get some false negatives on very low positives, but positives stay positive.”

About 40% of all samples received from the area were previously thrown out. Maichak has also tried to improve the samples on his end by putting out coolers, picking up samples quicker and spinning down samples himself instead of sending them to Laramie to be spun down. The department has also offered to clean up infected aborted fetuses if called, but it has yet to be notified of problem areas.