Washington federal appeals court Tuesday retained federal protection for grey wolves in the western Great Lakes region, ruling that the government made crucial errors when it dropped them from the endangered species list five years ago.

The court upheld a district judge who overruled the U.S. Fish and Wildlife Service, which had determined that wolves in Michigan, Minnesota and Wisconsin had recovered after being shot, trapped and poisoned nearly out of existence in the previous century. That means the status quo of the past three years, disallowing hunting of Great Lakes wolves, holds. They’ve bounced back and now total about 3,800.

In a 3-0 ruling Tuesday, a panel of the U.S. Court of Appeals for the District of Columbia Circuit said the service had not sufficiently considered important factors. They included how loss of historical territory would affect the predator’s recovery and how removing the Great Lakes population segment from the endangered list would affect wolves in other parts of the nation.

As long as wolves are on the protected list, they cannot be killed unless human life is at risk. That means the three states cannot resume the hunting and trapping seasons they had when wolves were under their control.

Environmental advocates cheered the ruling on Great Lakes wolves, saying they remain vulnerable despite their comeback in recent decades.

“The second highest court in the nation reaffirmed that we must do much more to recover grey wolves before declaring the mission accomplished,” said Noah Greenwald, endangered species program director at the Center for Biological Diversity. “Wolves are still missing from more than 90 per cent of their historic range in the lower 48 states, and both the Endangered Species Act and common sense tell us we can’t ignore that loss.”

“The Michigan Legislature passed three separate laws to designate wolves as a game species in its zeal to allow the state to authorize a trophy hunting and trapping season for wolves and to undermine a fair election by Michigan voters on wolf hunting,” said Wayne Pacelle, president of the Humane Society of the United States, lead plaintiff in the original lawsuit affirmed Tuesday. He said Congress and wildlife regulators should “recognize that wolves provide an enormous range of ecological and economic services to the regions where they live, and they do it for free.”

Organizations representing farmers and ranchers, who want authority to shoot wolves preying on livestock, have long pushed to drop them from the federal list, which hunting groups also favours.

“There’s no question the wolf packs have recovered,” said Zippy Duvall, president of the American Farm Bureau Federation. “We only wish we could say the same of farms and ranches within their reach.”

By designating a “distinct population segment” of wolves in the western Great Lakes region in 2011, the Service made this precise error, effectively turning wolves in other portions of the nation into legal orphans. In 2013 the Service used this “orphan” legal status to then propose removing protections for gray wolves in the rest of the country, including California, Oregon and Washington, where small populations are still recovering, as well as the southern Rockies and Adirondacks, where there is suitable wolf habitat but no wolves.

The appeals court rejected the society’s arguments that wolves are still threatened by humans and disease and that state management plans wouldn’t safeguard them. But the judges said the process used by the Fish and Wildlife Service to remove protections from the wolves was fatally flawed.