PREDATORS -- More and more evidence indicates wolves are gaining ground across the state.

A gray wolf was struck and killed by a vehicle Monday on Interstate 90 between North Bend and Snoqualmie Pass.

"It's one of the first gray wolves confirmed killed west of the Cascade Crest since the state's first wolf pack was confirmed in 2008," said Dave Ware, Washington Department of Fish and Wildlife wolf policy lead.

Closer to home, wolf tracks and scats have been documented on Mount Spokane over the past few months by a man who says he contracts with Defenders of Wildlife. He also says he has recent video of what may be a pair of wolves, but has not turned it over to Washington Fish and Wildlife Department officials.

"Now we apparently have one more reason for people to keep their dogs on leashes when they bring them up here," said Steven Christensen, Mount Spokane State Park manager. 

"The other reason is that it's the law.  But if there are wolves up here, they are known to be aggressive to dogs they perceive as a threat to their territory."

State Fish and Wildlife officials say they have no confirmation that wolves are on Mount Spokane, yet.

However, state live-trapping efforts to tag and radio collar more wolves for monitoring are starting up.

"This is when pups are emerging from their dens, and the older members of the packs are making regular hunting trips into adjacent areas to bring food back to rendezvous sites," Ware said. "This makes the adult wolves vulnerable to our trapping efforts, which is important to our ability to monitor wolf population growth and minimize conflicts with livestock."

State biologists likely be watching Mount Spokane, and trappers also will be looking for more sign near Snoqualmie, where the discovery of a wolf pack would be big news and a game-changer in wolf policy.

Wolves can be delisted from state endangered species protections after a specified number of breeding pairs are in each of three areas of the state. So far, none has been documented in Western Washington.

The wolf killed on I-90 could be the harbinger of wolf packs to come.

"This is pretty good evidence that wolves are probably moving into and around western Washington, although we have not yet documented a pack," Ware said.

Since wolves are still under federal Endangered Species protections on the West Side of the state, the U.S. Fish and Wildlife Service is investigating. DNA tests will be used to confirm that the animal is a wild gray wolf and not a hybrid.

Andy Walgamott of Northwest Sportsman magazine points out in his blog that if the Snoqualmie canine is confirmed a wild wolf, it would be at least the fourth that’s been struck and killed by a vehicle in Washington.

Others include one near Tum Tum west of Spokane in 2008, another on the north side of Blewett Pass in 2013 and the other Ruby Creek female in Pend Oreille County last year.

Losing the Snoqualmie wolf to a vehicle collision isn't likely to seriously set back wolf recovery, Ware said.