Washington Drought Leading to Spike in Deadly White Tail Deer Illnesses

Aug 20, 2021

White Tail Deer at risk of two diseases. Those diseases usually do not impact domestic animals, Elk, or other types of deer.
Credit Wikimedia Commons

As drought conditions continue in Washington State, dry conditions and stagnating water are starting to impact Eastern Washington’s White Tail Deer population.

According to the Washington State Department of Fish and Wildlife, 50 deer have died outside of Colfax in the last few weeks from two drought related illnesses.

Two diseases are impacting Washington’s White Tail deer population this summer, Epizootic Hemorrhagic Disease – or EHD and Blue Tongue.

Michael Atamian is a biologist for the Washington State Department of Fish and Wildlife who covers Spokane, Lincoln and Whitman Counties. He said the only way to tell the difference between the two diseases is in a lab, their symptoms are mostly the same, and deer contract both diseases when they’re bit by gnats. The diseases cause bleeding internally and can kill a deer in about 48 hours.

He said the biggest fatalities so far have been in Whitman County.

“There are a fair amount of White Tails down there, concentrated in one area, and if the gnats are there and biting, and they’re all being held in that same area for a limited amount of water, they’re getting exposed.”

Atamian said during a wet year, deer have far more places to find safe drinking water, and few are infected. In addition to the Whitman County deaths, half a dozen deaths have been reported in other areas, including Spokane, Harington and Davenport.

“White Tail Deer are very susceptible to these diseases, and typically die when they get them. Mule Deer, Elk, Big Horn Sheep, they do not typically die when they get these diseases.”

Atamian said the last serious outbreak of these diseases was in 2015, and that was followed by several harsh winters – which also reduced deer populations. He said its too early to know whether this summer’s outbreak could exceed previous numbers.

“This is a pretty understudied, and currently still being studied type of disease, it’s not something there’s a lot of hard science on.”

The high number of deaths have led to hunting restrictions in this region for un-antlered White Tail Deer going into this hunting season.

Atamian said deaths from these diseases will stop once the first freeze hits the area, killing off adult gnats. Until then, community members should report White Tail deaths to the Washington State Department of Fish and Wildlife if it looks like they may have had one of these diseases.

He said symptoms of these diseases include lethargy, difficulty standing or walking, and excess saliva or foaming at the mouth.

Deer that are sick with this disease will often stay near water.

He said if a landowner or hiker finds a dead deer that looks otherwise healthy, it likely succumbed to one of these fast-acting diseases.