Lobster boats rest at their moorings in Peggys Cove, N.S. on Thursday. (Andrew Vaughan/Canadian Press)

One of the world's most endangered marine mammals is getting some help from a small group of eastern Canadian fishermen who are trying to reduce a major threat to the animals by controlling the amount of lethal fishing line in the water.

Lobster fishermen on the East Coast are altering the way they set lobster traps and will steer clear of rare North Atlantic right whales as they pass through the Bay of Fundy in a bid to cut the number of times they get snarled in fishing line.

Starting Monday when the lobster season opens in parts of the Bay of Fundy, hundreds of lobster harvesters will be asked to set their groundlines on the ocean floor to limit floating ropes and protect the whales against one of their two main killers.

Hubert Saulnier, a veteran fisherman in the Bay of Fundy where many of the massive mammals go to feed in the summer, said the initiative should reduce the amount of fishing line that floats above the ocean floor and ensnares the whales.

"We decided to be proactive and do studies and see what works," he said from New Minas, N.S.

"The best solution is to try to explain to fishermen what we've experienced on how to set gear properly.… It is a way to promote the fact that we should be involved a lot more and we should be informed a lot more."

Lines that link the lobster traps on the ocean bottom can be slack and close together, creating something like a noose that can wrap around the whales as they travel to and from waters off Florida.

Fishermen in two of the bay's fishing areas have agreed to make the lines tighter and longer to try to keep them resting on the ground.

They have also been asked to shorten the vertical lines that attach the traps to a buoy and are often found to be hazardous to the whales, whose population has dwindled to only 400 since they were hunted to near extinction in the 1700s.

Bob Rangeley of the World Wildlife Fund, which worked with fishermen to develop the measures, said they could go a long way to protecting the slow-moving, 17-metre animals that are also vulnerable to ship strikes.

"It's hugely significant," he said in Halifax. "They are the most endangered whale and we do have to reduce the threat. So this is a significant first step."

It's estimated that 75 per cent of the remaining North Atlantic right whales have scars on their bodies from fishing line, which they run into as they journey from their breeding grounds off Georgia and Florida to the Bay of Fundy in June.

The ropes can cause fatal infections, drown the whale on the ocean floor or prevent them from eating properly if they wrap around the mouth.

Saulnier, who once helped pull 58 traps, eight anchors and many balloons off a humpback whale, said they decided to move ahead with the voluntary initiative after a controversial lobster gear decision in the United States.

American officials are phasing out "floating" lines and mandated expensive weighted lines, which are intended to keep the line on the sea floor.

Saulnier studied the weighted lines for the Department of Fisheries, but said they aren't suited to the bay's strong currents.

Canadian Fisheries officials have said they're not considering a ban on the floating lines, but are looking instead at alternate gear types and simple avoidance of areas where the whales have been seen.

Moira Brown, a leading right whale researcher, praised the Canadian initiative, but said it could be hard to ensure fishermen are actually complying with the goodwill measures.

"The entanglement problem is a really difficult problem," she said from the New England Aquarium in Boston. "They're pointed in the right direction. Nobody wants to regulate this, but how do you get broad compliance? That's what you have to do to turn things around."