MINNEAPOLIS — Pressure is building in Congress to take gray wolves in the western Great Lakes region and Wyoming off the endangered list, which would allow farmers to kill the animals if they threaten livestock.

Representatives from Minnesota, Wisconsin, Michigan, and Wyoming have asked House Speaker Paul Ryan of Wisconsin for a fast floor vote before the season during which most cows and sheep will give birth begins in earnest.

That followed testimony before a Senate committee a week earlier from the president of the Wisconsin Farm Bureau Federation, who said producers need to be able to defend their livestock and livelihoods.

Meanwhile, both sides in the debate are waiting for a federal appeals court to decide whether to uphold lower court rulings that put wolves in the four states back on the list or to let the US Fish and Wildlife Service return management of the species to the states, which it has wanted to do for years.

US Representative Collin Peterson of Minnesota, the ranking Democrat on the House Agriculture Committee, sent a letter cosigned by seven of his colleagues from the four states to House leaders urging a quick floor vote on a bill to return their wolves to state management.

A key component of both is language that would prevent the courts from intervening.

The representatives said it’s urgent because calving season is when cows and calves are most vulnerable.

Peterson said in an interview that they very nearly passed a similar provision in the last Congress and that he thinks they have a decent shot at persuading Ryan to grant an early floor vote.

Otherwise they’ll try to attach the language to a bigger appropriations bill later. The legislation is similar to what Congress used to delist wolves in Montana and Idaho in 2011 after courts blocked the federal government’s attempts to lift protections in those states.

Gray wolves were once hunted to the brink of extinction in the lower 48 states, but they recovered under Endangered Species Act protections and reintroduction programs to the point where they now number around 5,500, according to the service.

The combined gray wolf population of the three western Great Lakes states is now about 4,000, while Wyoming has roughly 400. The agency describes wolf numbers in those states as ‘‘robust, stable and self-sustaining.’’

But federal courts have blocked multiple attempts to take them off the endangered list, most recently in 2014. The US Court of Appeals for the District of Columbia Circuit last fall heard oral arguments in challenges to those rulings but hasn’t ruled on them yet.

Associated Press