PORTLAND, Maine (AP) A U.S. appeals court has reinstated a ban on lobster harvesting in hundreds of miles of productive fishing waters off the Maine coast to try to protect rare whales.

The Maine Lobstering Union had won emergency relief to stop the closure of lobstering grounds, which federal regulators ruled was needed to help protect endangered North Atlantic right whales from extinction.

But the 1st U.S. Circuit Court of Appeals ruled Tuesday that the closure is back on. Removing the ban prevents the government from performing its task of protecting the whales from death by entanglement in gear, the court ruled.

The government’s role is “assuring the right whales are protected from a critical risk of death,” the court ruled.

The whales number less than 340 and are vulnerable to lethal entanglement in fishing gear and collisions with large ships. The New England lobster fishery has had to contend with a host of new restrictions to try to protect the whales. The new rules make an approximately 950-square-mile area of the Gulf of Maine essentially off limits to lobster fishing from October to January.

The appeals court’s ruling sent the case back to the U.S. district court level to resolve any disputes that concern the removal of the banned gear from the restricted area. Previously, the district court ruled there was not enough evidence the whales gather in the area with enough frequency to render it a whale “hot spot.”

The court’s decision affirms that “reducing entanglements by prohibiting fishing in this area is critical to ensuring the survival of right whales,” said Erica Fuller, a senior attorney at the Conservation Law Foundation.

Commercial fishing groups have criticized the National Marine Fisheries Service over the right whale rules and said the rules threaten to endanger the future of Maine’s iconic fishery while failing to protect the whales.

The Maine Lobstermen’s Association will continue to fight the fishing restrictions in court, said Patrice McCarron, the group’s executive director.

“Nevertheless, it foreshadows the grave future our lobster fishery faces if NMFS’s 10-year whale plan is not rescinded in favor of a plan based on science,” McCarron said.