SALEM, Ore. (AP) — A two-year search for wolves in Washington’s South Cascades has found none, a scientist said Wednesday.

Researchers tested the DNA of thousands of scat piles sniffed out by dogs. Many piles looked like wolf droppings, but all turned out to be from dogs, said Samuel Wasser, director of the University of Washington’s Center for Conservation Biology.

If wolves are in the South Cascades, they are lone wolves, he said.

“There’s no way there’s an established pack,” he said. “We would have picked that up.”

State lawmakers funded the study in part to learn how far west and south wolves have advanced in Washington. Recovery won’t be complete until at least four packs are producing pups in the South Cascades, according to the state’s wolf plan.

Researchers collected about 2,400 scat samples from carnivores, such as bobcats, coyotes and black bears, between Interstate 90 and the Columbia River.

The search for wolf scat will resume for a third year this month. Even if no wolf droppings are found, the study will show the distribution and diet of other carnivores, Wasser said.

Washington had at least 145 wolves at the end of 2019, according to a combined count by Fish and Wildlife and the Colville Tribes. Wolves are on the state endangered species list and federally protected in Western and Central Washington.