President Donald Trump speaks during a roundtable discussion with commercial fishermen at Bangor International Airport in Bangor, Maine, Friday, June 5, 2020. Credit: Patrick Semansky | AP

President Donald Trump signed a proclamation opening a national marine monument off the Gulf of Maine to commercial fishing during his Friday visit to Bangor, although he may not have the authority to do so and the move invites a legal challenge.

The order would allow fishing to resume in the Northeast Canyons and Seamounts Marine National Monument while canceling a planned phase-out of lobster and crab fishing in the area. The move was supported by fishing interests but risks a legal showdown with environmentalists, though the area is out of range for most Maine fishermen.

The president signed the proclamation while meeting with fishing industry leaders in Bangor, touching also on tariffs and regulations meant to protect endangered North American right whales. The monument was created in 2016 during the administration of former President Barack Obama and covers about 5,000 square miles of offshore land southeast of Cape Cod.

It is seen as a biodiverse haven for sea corals, endangered whales and numerous fish species. The monument was the subject of a federal court battle in recent years, as fishing, lobster and crabbing industry groups contended that the designation restricted where they could fish. The designation was upheld by the U.S. Court of Appeals in Washington, D.C., last year.

On Friday, Trump slammed the monument designation under Obama as “deeply unfair to Maine lobstermen” and a threat to family businesses.

“I can’t even believe they would do a thing like that,” he said. “It’s a terrible thing.”

Trump’s actions are likely to be followed by a legal challenge centering on the 1906 Antiquities Act and the power it gives presidents over national monuments. While the law gives a president the right to designate monuments, it does not expressly allow the president to modify them.

In a statement, Brad Sewell, senior ocean policy director for the Natural Resources Defense Council — an international environmental lobbying group that supported upholding the monument during the federal court battle — said that fishing would threaten the monument’s delicate ecosystem and entangle animals that thrive there. He said his organization was prepared to sue the government to protect the site.

Those kinds of threats have not stopped presidents from altering monuments in the past. Trump, a Republican, has characterized the antiquities law as a “massive federal land grab” and has made dramatic changes to monuments before, despite ongoing questions about legality. His most notable move was to shrink two Utah monuments — Bears Ears and Grand Staircase-Escalante — in 2017 to eventually offer their use to energy developers and ranchers.

The antiquities law was central to the federal suit challenging the Atlantic monument’s designation. Plaintiffs argued that Obama, a Democrat, exceeded his authority by establishing the monuments in the ocean and that the law only gave him the right to do so on land.

Members of Maine’s congressional delegation panned the decision. U.S. Rep. Jared Golden, a Democrat from the 2nd Congressional District, said the policy change would mostly benefit fishermen in Massachusetts. Rep. Chellie Pingree, a Democrat from the 1st District, said the president had acted outside his authority by making the decision.

Rep. Billy Bob Faulkingham, R-Winter Harbor, a lobsterman who backs Trump, said fishing crews out of Portland and Portsmouth — just over the border from Maine — frequently fish the Georges Bank, an elevated stretch from Cape Cod to Cape Sable Island in Nova Scotia encompassing part of the monuments.

The lobster industry has lost millions of dollars in exports due to the China tariffs, though the two countries reached a tentative agreement to exempt them in January. Off the cuff, the president also threatened to impose tariffs on cars imported from Europe if the European Union did not reduce tariffs on lobsters.

During the roundtable, Kristan Porter, president of the Maine Lobstermen’s Association, raised the issue of proposed federal regulations that aim to protect whales but lobstermen say are overly restrictive. Maine’s congressional delegation has lobbied the government to reconsider the rules, which would require lobstermen to use less fishing line and switch to a weaker type.

Trump only committed to looking into the issue that has brewed for a year before regulators.

“I want to protect the whale, too,” he said. “As long as we can protect the whale, I’m going to do it.”

BDN writer Jessica Piper contributed to this report.