Scientist: Wolves ‘habituated’ to eating cattle never change their diet

By Eric Mortenson

Special to Wallowa County Chieftain

Published on September 5, 2017 4:17PM

Last changed on September 5, 2017 4:29PM

A wolf researcher says that an incremental approach to culling wolves from Oregon’s Harl Butte Pack will likely fail if the wolves have become habituated to eating cattle.

Chieftain File Photo

A wolf researcher says that an incremental approach to culling wolves from Oregon’s Harl Butte Pack will likely fail if the wolves have become habituated to eating cattle.


Some wolves may have become “habituated” to eating cattle. Northeast Oregon cattle ranchers have called for two entire packs to be killed, saying the state’s “incremental” approach won’t deter voracious wolves.

Tracks indicated a 500­-pound calf churned 150 feet up a slope, leaving blood splattered on four logs, before going down in a pile of Meacham Pack wolves. There wasn’t much left when a ranch hand found the carcass Aug. 19, perhaps two or three days after the attack.

Most of the calf had been devoured, except the vertebrae with ribs, pelvis and tail still attached. The calf’s lower jaw and contents of its rumen were nearby.

It was the pack’s fourth confirmed attack within a week, all on livestock grazing on a 4,000-acre private forested pasture in the Sheep Creek area of Umatilla County. The producer asked ODFW to take “lethal control” against the Meacham Pack as allowed under Phase 3 of Oregon’s wolf management program.

The rancher wanted them all dead. The wildlife agency authorized killing two of them, an incremental approach it had taken earlier in August with Wallowa County’s Harl Butte Pack, which had attacked livestock eight times since July 2016.

In that case, ODFW quickly shot two adult Harl Butte wolves, then a third and fourth in the days that followed as it appeared the pack was still going after calves.

The Oregon Cattlemen’s Association argued that ODFW’s approach was a waste of time. Even with four dead, the Harl Butte Pack consisted of six adults and three growing pups –– a 33-pound pup was unintentionally trapped, then released unharmed, as ODFW pursued the adults.

The Meacham Pack, meanwhile, had seven members at the end of 2016 and added at least four pups this past spring. As Wallowa County rancher Todd Nash put it, “big dogs” eat a lot of meat.

The apparent spike in livestock attacks in August raised questions. ODFW said Oregon’s unusually warm and dry summer — even Portland went 57 days without rain — caused deer and elk to move to higher ground. With their natural prey more scarce, wolves then turned to attacking cattle, went the explanation.

But as Northeast Oregon research scientist Jim Akenson pointed out, deer and elk go to higher ground every summer. That’s not new, although conditions were more severe this year.

Instead, Akenson believes the packs may be “habituated” to eating cattle. For that reason, he said, ODFW’s incremental response –– killing two adults at a time and monitoring the effect on pack behavior –– probably won’t work. Once the pack members “flip that switch” in terms of prey selection, it is tough to deter them, he said.

“They’re habituated to easy pickings,” Akenson said. “Plucking out a couple individuals is probably not going to change that behavior.”

Akenson is conservation director for the Oregon Hunters Association. His wife, Holly Akenson, is a wildlife biologist and member of the ODFW Commission, which is expected to revise and adopt the state’s wolf management plan this year.

The Akensons live in Enterprise and have extensive wildlife and wilderness experience in the Pacific Northwest.

ODFW does not characterize the wolves as habituated to livestock.

Spokeswoman Michelle Dennehy noted that only one confirmed calf kill was attributed to the Harl Butte Pack in a month’s time, meaning the wolves “are clearly relying on native prey (deer and elk) as their primary food source.”

John Stephenson, a U.S. Fish and Wildlife Service biologist based in Southwest Oregon, said larger packs tend to go after livestock.

“There’s a relationship between pack size and increased incidents of depredation,” he said.

Location is another factor. He said the Harl Butte Pack operates where several herds graze on a mix of public and private land. All of its attacks over the past year were within nine miles of each other, according to ODFW.

The Imnaha Pack formerly prowled the territory and was known for attacking livestock. ODFW shot four Imnaha Pack wolves in April 2016 after repeated attacks on calves and sheep.

Dennehy, the ODFW spokeswoman, agreed deer and elk move to higher elevation in late summer and fall. The Harl Butte Pack has not followed them to higher ground, but remains in a more limited geographic area than the predecessor Imnaha Pack used.

“This may be due to another pack or group of wolves using territory at higher elevation,” she said in an email. Meanwhile, all of the Meacham Pack’s attacks in August took place on the same private pasture.

As of Aug. 30, none of the Meacham Pack had been killed.

Conservation groups oppose killing wolves and have asked, without success, for Gov. Kate Brown to intervene in ODFW’s decisions. The groups, including Oregon Wild, believe ODFW should not be taking lethal action until Oregon’s outdated wolf management plan is reviewed and revised. The ODFW Commission is expected to take action on the plan this year.



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