White-tailed deer populations in parts of Eastern Montana and elsewhere in the Northern Plains could take years to recover from a devastating disease that killed thousands of the animals in recent months, wildlife officials and hunting outfitters said.

In northeast Montana, officials said 90 percent or more of whitetail have been killed along a 100-mile stretch of the Milk River from Malta to east of Glasgow. Whitetail deaths also have been reported along the Missouri and Yellowstone rivers in western North Dakota and Eastern Montana and scattered sites in Wyoming, South Dakota and eastern Kansas.

The deaths are being attributed to an outbreak of epizootic hemorrhagic disease, or EHD. Transmitted by biting midges, EHD causes internal bleeding that can kill infected animals within just a few days.

“I’ve been here 21 years and it was worse than any of us here have seen,” said Pat Gunderson, the Glasgow-based regional supervisor for Montana Fish, Wildlife and Parks. “Right now it’s going to take a few years to get things back to even a moderate population.”