Cougars Kill Wolves in Washington, Raising Questions About Predator-on-Predator Dynamics


It's dog-eat-dog out there, except occasionally in Washington when it becomes cat-eat-dog.

Since 2013, cougars have killed at least four collared wolves and state biologists believe that number is likely higher.

"That's more than has been documented in the entire Northern Rocky Mountains in twice as much time, despite that being a much larger area with many more wolves than Washington," wrote the Washington Department of Fish and Wildlife in a Medium post last week. "And, it is likely there are more cases that we don't know about."

The report stemmed from an incident earlier this summer where a wolf in the Dominion pack was found dead by WDFW biologists. Agency biologist Trent Roussin found the wolf in a steep and treed canyon. After investigating the death Roussin found holes in the wolf's head, consistent with bite marks from a cougar.

"From all the signs at the site, it appears the wolf was attacked while traveling down an old overgrown logging road, with the fight ending about 100 yards downhill," Roussin said in the post from last week.

Washington officials have chatted with biologists from other states and it seems that the cat-on-dog violence is rare, if nonexistent, in other areas with robust wolf populations.

"It was uncommon enough that when staff started asking about this, most biologists who studied wolves and cougars couldn't think of an instance of a wolf being killed by a cougar," said Roussin. "It was unusual during the first 20-plus years of wolf recovery in the Northern Rockies — Montana, Idaho, and Wyoming."

A cougar is no match for a wolf pack. However, one-on-one a cougar can kill a wolf, according to WDFW. As for motivation? It's likely competition over prey (i.e., deer and elk) rather than hunting.

But why in Washington? That remains unanswered, although the multiyear Washington Predator-Prey Project is looking at the various dynamics between wolves, cougars and prey species.

"The hope is that what we learn from this five-year study will help not only inform decisions that are made on how to best manage each of these species in Washington, but also give us more insight into interactions that have been rare until now such as cougar attacks on wolves," WDFW's post concludes.

The observations highlight an important fact: There is much we don't know about how wild animals interact, particularly in an urbanized state like Washington.

Cougars in particular — notoriously sneaky as they are — have been difficult to study. Modern technology is beginning to fill in the gaps.