38 whitetail deer in eastern Washington dead from deadly hemorrhaging diseases, including bluetongue

Two viral and drought-related diseases have killed 38 whitetail deer in Eastern Washington.

Two whitetail deer near Davenport, Wash., tested positive for bluetongue and epizootic hemorrhagic disease (EHD) this week. Meanwhile, 36 deer near Colfax  are believed to have died from EHD.

Reports of dead whitetail trickled in last week, prompting the Washington Department of Fish and Game to collect samples from some dead deer. Results from the Washington Animal Disease Diagnostic Lab in Pullman came back Thursday.

“We are bracing ourselves for this being a pretty bad year,” said WDFW veterinarian Kristin Mansfield.

Animals can die in a few days once symptoms or mouth and nasal discharge occur.

“We are asking people if they find deer dead or acting unusually or whatever to report them,” said Staci Lehman, a spokeswoman for WDFW.

Bluetongue is closely related to epizootic hemorrhagic disease, which is common in whitetails in September but usually on a small scale and in isolated areas. Bluetongue is a variety of hemorrhagic disease and can affect a wider range of animals, including sheep.

The two diseases are similar and not well understood. Biologists don’t know where the virus spends the winter or why outbreaks seem to occur roughly every decade, Mansfield said.

“They affect the animal exactly the same way,” she said.

Both diseases are spread by biting Culicoides gnats, and neither spreads to humans, although wildlife officials discourage hunters from shooting and consuming animals that are obviously sick.

Michael Atamian, the district biologist for WDFW, said if the outbreak is bad enough, it could impact hunting seasons although that depends on the extent and severity of the outbreak.

Widespread wildfire and drought will likely limit hunting access in some areas this fall. A disease outbreak only adds to the stress on Washington’s wildlife.

“It’s going to be tough with drought conditions as it is,” said Marie Neumiller, the Inland Northwest Wildlife Council’s executive director.

In 2015, an outbreak of bluetongue and EHD disease killed several hundred whitetail in Eastern Washington. That was followed by severe winter conditions in 2016 and 2017. Decreased hunter-harvest prompted the WDFW commission to eliminate antlerless deer hunting in northeast Washington in 2019. They cited decreased whitetail numbers following the outbreak and harsh winters.

Large outbreaks of EHD happen roughly every decade, Mansfield said, and seem to occur during drought years. Why that happens isn’t totally clear, she said.

“It’s an active of area of research,” she said.

One theory is that during a drought, sparse water access concentrates ungulates around available ponds, streams and marshes, which provide prime gnat habitat.

“That is the conventional wisdom, and it does stand to reason,” she said.

Significant Eastern Washington EHD outbreaks also coincided with drought conditions in 1988 and 2004. Whitetails in the Kamiah, Idaho, area required several years to rebuild populations after a major EHD outbreak in 2003.

Earlier this week, the Idaho Department of Fish and Game announced that approximately 250-300 whitetails have died near the Kamiah area from a type of hemorrhagic disease.

WDFW officials have continued to field reports, including a report of a sick deer near Otis Orchards, Mansfield said.

“We don’t know what the impacts are, really, at this time,” Lehman said. “It depends on how many animals do die from it.”

CORRECTION: Due to a reporter’s error the number of deer tested was incorrectly stated. The story has been updated.