SPOKANE — A federal judge has rejected plans by a federal agency to assist in the killing of problem wolves in Washington.

U.S. District Court Judge Robert Bryan of Tacoma issued a summary judgment last Thursday against the low-profile agency, known as Wildlife Services.

Bryan said the agency should have prepared a more in-depth environmental analysis of its agreement with the state of Washington to help kill problem wolves.

Bryan ruled in favor of conservation groups that sued the agency, concluding that an environmental assessment prepared by the agency was flawed.

Wolves were hunted to extinction in Washington at the turn of the last century. But they started migrating from neighboring areas in the early 2000s and there are an estimated 16 wolf packs containing 68 wolves in the state, all in eastern Washington.

Wildlife Services failed to create a full environmental impact statement about the proposal to reduce wolf conflicts in the state, Bryan ruled.

Wildlife Services is a program within the U.S. Department of Agriculture that is responsible for controlling the number of wolves, grizzly bears, coyotes and other wild animals. Officials at the agency didn’t have a response on the ruling.

Environmental groups cheered the ruling.

“It is long past time that we base wildlife management decisions on the best available science, not on antiquated, anti-wolf rhetoric and myth,” said Bethany Cotton of WildEarth Guardians.

Environmental groups contend the environmental assessment failed to address the full ecological impacts of killing wolves in Washington, including impacts on wolves in neighboring states and on other animals, such as grizzly bears and Canada lynx.

Wildlife Services has been involved in the killing of wolves in Washington in the past.

In August 2014, Wildlife Services snipers shot from a helicopter and killed the Huckleberry wolf pack’s alpha female. The death of that pack’s breeding female threatened the future of the entire pack, environmental groups contended.

Wildlife Services also advised the Washington Department of Fish and Wildlife in the 2012 destruction of the Wedge wolf pack in Eastern Washington. In that case, the state agency killed seven wolves after they preyed on livestock.

At the federal level, the state is split into two separate wolf populations. In the eastern third of the state, wolves are considered part of the large Northern Rocky Mountain population, which was removed from the endangered list in 2011. But in the western two-thirds of the state, wolves are considered part of the Pacific Northwest population, which is much smaller and still listed as endangered.