The National Marine Fisheries Service has agreed to settle a lawsuit filed by environmentalists and says it will issue new rules aimed at preventing Hawaii fishermen from accidentally hooking a rare dolphin species when fishing for tuna and swordfish.

The settlement with the Center for Biological Diversity and Turtle Island Restoration Network requires it to issue new regulations by Nov. 30.

The agency published a draft of rules last year to protect the dolphins called false killer whales but never followed with a final version that would have put the regulations in place. The environmental groups, represented by Earthjustice, sued in June to force the agency to follow up.

The dolphins are accidentally caught in the longline fishery at high rates, in part because they eat many of the same fish the fishermen are catching. The hooks snag false killer whales when the dolphins try to eat the fish caught on the lines.

Members of one false killer whale group living in water up to 60 miles from Hawaii have been killed and seriously injured at three times the sustainable level for the population, the lawsuit said. Another group — in water farther off the coast — is being killed and injured at four times the sustainable rate.

David Henkin, an Earthjustice attorney, said the accidental hookings have continued in the months since the agency was supposed to have issued new regulations. The tuna and swordfish fishery snagged at least two, and as many as four, of the dolphins in the first half of 2012, he said.

The agency didn’t immediately respond to a request for comment.

Almost all of the new rules proposed by the agency in July 2011 were developed by a task force of scientists, fishermen, conservationists, and civil servants.

One proposed rule would close an area south of the main Hawaiian Islands to the longline fishery once a given number of false killer whales have been killed or injured in a given year. The next year, the agency would lower the number.