PORTLAND, Maine (AP) — A federal appeals court on Friday upheld former President Barack Obama’s designation of a federally protected conservation area in the Atlantic Ocean, a move that commercial fishermen oppose.

Fishing groups sued over the creation of Northeast Canyons and Seamounts Marine National Monument, a 5,000-square-mile area that contains fragile deep sea corals and vulnerable species of marine life. The monument was established in 2016.

A federal judge dismissed the lawsuit last year, and the Court of Appeals for the District of Columbia Circuit upheld the decision Friday.

The appeals panel brushed aside arguments that federal law governing monuments applies only to land, not oceans; that the area of the ocean is not “controlled” by the federal government; that it is not compatible with National Marine Sanctuaries Act; and that it is not the “smallest area compatible” with management goals.

The Natural Resources Defense Council and the Conservation Law Foundation applauded the legal decision.

“Like one of America’s very first national monuments, the Grand Canyon, the Northeast Canyons and Seamounts is a natural treasure. It provides habitat for a wide range of species, from endangered whales to Atlantic puffins to centuries-old deep-sea corals,” said Kate Desormeau, senior attorney for the Natural Resources Defense Council.

The area is the only marine monument in the Atlantic Ocean and is one of five marine monuments nationwide.

Attorney Jonathan Wood, who represents the fishing groups, said previously that the matter deserves to be heard by the U.S. Supreme Court but that he would need to consult with his clients before making a final decision.

The appeals court “gets the law wrong and ignores critical arguments” and conflicts with a decision from another appeals court, “creating an important split which the Supreme Court may need to resolve,” Wood wrote in an email.