Cook later said he had heard of 10 fishing boats being stopped by American agents in recent weeks.
The agents claimed to be looking for undocumented immigrants, he said.
He has argued that Canada and the US should submit the disagreement to arbitration at the world court. Both countries claim the island, which is about 10 miles off ME and home to two full-time residents (both Canadian), puffins, rocks and not much else, and say they have the right to patrol its boundaries. By now, most of the local lobstermen have been questioned by Border Patrol, Drouin added.
Emily Gilbert, a University of Toronto professor who researches the US-Canada border, told Business Insider that it's common for the both the US Coast Guard and the Royal Canadian Mounted Police to patrol those waterways. He said he found the Border Patrol operation "entirely farcical".
"If the Canadians want to use the term harass, they have been harassing us for years", Drouin said. However, he hasn't been able to get a good answer for the sudden uptick in patrols.
According to Cook, the Canadian fishing captain, Nick Brown, informed the USA vessel that "he was a Canadian vessel legally fishing in Canadian waters". "They say it's routine patrolling, but it is the first routine patrolling in 25 years". "We've seen them in the past, but not on this scale".
The suggestion that the border agents were looking for illegal immigrants seems improbable, he said.
Trudeau has also been critical of the White House's hardline "zero tolerance" immigration policies and the consequent result of family separations at the border, saying that it's "not the way we do things in Canada".
Malin would not say how long the operation lasted or if it is ongoing.
U.S. Customs and Border Protection has not responded to a CBS News request for comment. Customs and Border Patrol has its own boats and aircraft.
According to Cohen, those seeking to cross the Canada-U.S. border illegally are usually pushing north.
As tensions rise between the United States and Canada, there is a new clash in the cool waters off the northeast tip of ME, which are rich with lobster, scallops and cod. The disputed area covers about 277 square miles. "Law Enforcement at the Border is doing a great job, but the laws they are forced to work with are insane". "We are concerned that they are out of control".
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"Sometimes doing nothing is better", he said.
Canada is investigating incidents of U.S. patrol boats straying into waters it claims as its own and approaching Canadian fishing vessels.
The area in question is around Machias Seal Island, an 8-hectare (20-acre) rock island at the Maine-New Brunswick border.
"There's been a bit of a misunderstanding there somewhere", Laurence Cook, chairman of the advisory board for Lobster Fishing Area 38, said.
US Customs and Border Protection confirmed that they've stopped 21 Canadian vessels off the coast of ME this year, but made no immigration arrests.
"We understand that a few Grand Manan fishermen were approached United States Border Patrol during the month of June".
A United States customs spokesperson said the operation, which is being conducted by the agency's Houlton, Maine, office, is part of a routine enforcement effort and such inspections have been made in the past.
The Canadian government is investigating incidents that occurred in Canadian waters, and engaging USA agencies involved in the matter, said John Babcock, a spokesman for Global Affairs Canada, in an email.
Elizabeth Read, a Global Affairs spokeswoman, said that "Canada's sovereignty over the Machias Seal Island and the surrounding waters is long-standing and has a strong foundation in worldwide law". "Until the matter of the boundary is resolved, we will continue to take practical steps with the U.S.to ensure that the area is well managed".
The Canadian flag flutters in the breeze by the lighthouse at Machias Seal Island. In 2007, according to the National Post, an American fisherman had his thumb torn off when his equipment became tangled during a dispute with a Canadian competitor.
The agents were enforcing "immigration laws and other violations of federal law", she said.
"Is this overkill? Absolutely".