I apologize, but I didn't quite catch the name.
Joseph-Elzéar Bernier made four trips to the Arctic and on one of these trips, he erected a plaque. He was a proponent of the sector theory, which, I can assure you, carries no legal weight. Nevertheless, I'm not saying that his gesture was meaningless.
He proclaimed Canadian sovereignty over the land, not the waters. He explained this in a book that he later wrote. He claimed all of the lands inside this triangle for Canada, that is from longitude 141 degrees to latitude 69 degrees, detouring around Greenland.
If the Canadian sovereignty claim involved only the lands and islands, then this gesture might mean something. However, it has no bearing in terms of our claim to Arctic waters, or especially in terms of the legal status of the routes through the Northwest Passage.