Watch for elk gathering this month near Rattlesnake Mountain

A cow elk has a frosty meal on the Hanford nuclear reservation before snowfall coated the ground at lower elevations.
A cow elk has a frosty meal on the Hanford nuclear reservation before snowfall coated the ground at lower elevations. Courtesy DOE

This could be a good month for people who do not have access to Hanford to spot some of the approximately 1,100 elk in the Rattlesnake Hills group that roams the area.

The snow tends to drive them to lower elevations, making travelers on Highway 240 more likely to spot some. The highway divides the former production portion of the Hanford nuclear reservation from the Arid Lands Ecology Reserve, which includes Rattlesnake Mountain.

Some workers at the closed Hanford nuclear reservation have seen abundant numbers since fall.

It’s likely the same group that returns each year, said Justin Wilde, wildlife biologist for Department of Energy contractor Mission Support Alliance.

After the fall mating season, elk form large groups, comprised of both cows and bulls, for the winter. They start to dissipate into smaller groups in the spring as males lose their antlers and join bachelor herds and cows and their young.

Wilde counted 90 on one November day after the fall rut ended and elk began forming large groups. They particularly like the abandoned Hanford town site on the nuclear reservation, where the limited trees and shrubs provide some cover.

As much of the environmental cleanup has been completed on the 220 square miles of the nuclear reservation along the Columbia River, the elk have been able to expand their range there.

Fewer workers are around to disturb them and, with less traffic, the number of animals hit by vehicles is down.

“Most of the wildlife in general is benefiting from the reduced footprint,” Wilde said, referring to the smaller area where cleanup work is ongoing.

Hanford workers may see the elk any time of day, but they are most often spotted at sunrise and sunset.

Farmers reported spotting elk in the area in 1969. But the beginnings of the herd that would settle at Hanford is usually traced to the winter of 1972-73. A bad storm drove them out of the mountains early, according to information from the Washington State Department of Fish and Wildlife.

The size of the herd grew slowly at first, and then more rapidly in the mid-1980s. The animals not only survived in the desert landscape, but thrived.

“There is a lot of land to roam and not a lot of predators,” Wilde said.

They are protected from hunting if they stay on the Hanford nuclear reservation and the Arid Lands Ecology Reserve. Their limited predators include coyotes, which might take a few very young elk, and the rare cougar that passes through.

Heidi Newsome, a biologist with the U.S. Fish and Wildlife Service, expects the elk to be more dispersed this year — Rattlesnake Mountain was burned in early August to stop a fire spreading toward the Hanford nuclear reservation.

Biologists saw them moving off the burned area after a 2007 fire and onto more public and private land, she said.

Elk will “eat any green vegetation they can get their lips around, pretty much,” Wilde said.

The snow should not be too deep now for elk to eat grasses, Newsome said. But Fish and Wildlife is concerned about the pressure on smaller native springs on the Arid Lands Ecology Reserve after the summer fire. Vegetation can be trampled by elk seeking food and water there.

The agency is trying to do some post-fire rehabilitation at springs and may have to put up temporary fencing to keep elk out.

The 1,100 estimate of the Rattlesnake Hills elk group is based on a survey in 2015. More will be known when information is compiled from another survey this winter by the U.S. Fish and Wildlife Service, which manages the Arid Lands Ecology Reserve as part of the Hanford Reach National Monument.

Annette Cary: 509-582-1533, @HanfordNews