The escalating deaths of highly endangered North Atlantic right whales in Canada’s Gulf of St. Lawrence have had officials scrambling to find ways to stem the toll.
But measures to reduce the risk of ships striking right whales have not been implemented in the area because of a lack of scientific research, according to Moira Brown, a senior scientist with the Canadian Whale Institute and one of the world’s leading whale researchers.
“We’ve done a lot to reduce the risk of vessel strikes, and up until this year in the Gulf of St. Lawrence we’ve seen fewer carcasses attributed to ship strikes,” Brown said. However, the gulf “is not an area where we’ve worked to put mitigation measures in place because the right whale scientific community really only began our research there in earnest a couple of years ago.”
Canadian officials have been at a loss over what to do about the recent spate of right whale deaths in the Gulf of St. Lawrence – 10 since June. Two more have died in other areas in that time period; the most recent was discovered on Tuesday, off Martha’s Vineyard in Massachusetts. The loss of 12 animals represents more than 2 percent of this endangered species’ population.
Three of the deaths seem to have resulted from ship strikes, preliminary necropsy results indicate, and one of the whales appeared to have drowned after becoming entangled in fishing gear. Some of the carcasses were badly decomposed, making it difficult to identify the cause of death. Fisheries officials have urged vessels to slow down and have closed the snow crab fishery in a part of the Gulf of St. Lawrence, but whales continue to die.
Scientists say past efforts to reduce collisions between oceangoing vessels and right whales – so dubbed because they were the “right” species to target when whales were hunted nearly to extinction in the 19th century – offer lessons for the Gulf of St. Lawrence. The action began in the early 1990s with a mariner-awareness program, Brown said. “It was in response to the deaths of right whales in the Bay of Fundy attributed to ship strikes based on necropsy results,” she explained. Blunt trauma on a whale isn’t likely to be caused by anything else, and that signs of internal bleeding indicate a collision occurred while the whale was alive.
So scientists formed a working group and consulted with the shipping industry and a government agency, Transport Canada, Brown said. They “worked with operators that are in communication with the vessels coming through the lanes” to let them know whales are in the area and that ship captains ought to take appropriate measures.
The strikes continued, though, so scientists took a different tack. Chris Taggart and his students at Dalhousie University analyzed at least a decade’s worth of data on whale movements from tagged animals along with vessel data. They found that “the ideal situation is to be able to separate vessel traffic and whales,” according to Brown. But the United Nations-chartered International Maritime Organization (IMO) had established the shipping lanes in the Bay of Fundy, northeast of Maine between New Brunswick and Nova Scotia – meaning Canada’s government couldn’t move them even though they were in its territorial waters.
In a precedent-setting move, Transport Canada went to the IMO in 2002 with a proposal that Brown, Taggart and others had worked up in consultation with the shipping industry to change how the vessels move through right whale habitat. “We had room to move the vessels away from a high concentration of right whales to an area of much lower concentration, reducing by 90 percent the risk of vessel strike in the critical habitat area,” where right whales are feeding, socializing and raising calves, Brown said.
Roseway Basin, south of Nova Scotia, presented a different problem: There were no designated shipping lanes there. Taggart’s analysis, however, led Transport Canada to lobby the IMO to establish an area to be avoided. The IMO eventually designated a quadrilateral nearly 1,000 square nautical miles in size. These changes were the first time the IMO, usually concerned with issues such as ship safety and the dumping of ballast water, had dealt with marine mammals.
Using data from the automated identification system that large ships are required to carry to broadcast their location, and an antenna that Dalhousie University researchers installed on Nova Scotia, researchers have demonstrated that around 80 percent of ship traffic complies with the recommendations. Those that do get a letter of congratulations; those that don’t receive a gentle reminder of the area’s existence.
“We haven’t had a vessel strike that we know of within the shipping lanes of the Bay of Fundy or the area to be avoided in Roseway Basin since the development of those mitigation measures,” Brown said.
Building on these successes, researchers helped convince the U.S. to develop a series of recommended routes in Cape Cod Bay. In 2007, shipping lanes leading into Boston harbor were moved, reducing the collision risk considerably. In 2008 a speed rule outside nine ports between Massachusetts and Florida was implemented, requiring ships to slow to 20 knots or less while making port.
“I can’t think of any ship strikes since then south of New York,” said Douglas Nowacek, professor of conservation technology at Duke University. “There used to be at least one a year in U.S. waters, but they’ve definitely gone down.”
Nowacek has spent the past couple of decades looking at whether acoustic warning systems can help reduce ship strikes. A leading manatee researcher at Florida Atlantic University recently announced that he has developed a device that successfully warns manatees of oncoming boat traffic, but Nowacek said such a system won’t work for right whales.
He conducted an experiment in the Bay of Fundy, playing an “annoying sound” to the whales. “They bolted to the surface and swam generally away from us, but not in any particular direction,” Nowacek said. Then they would swim at around 30ft (10m) below the surface – where they are invisible to ships. “If they came to the surface and kept blowing that would be perfect, but our only experience is that they did exactly the opposite of what we wanted them to do. They might go into the path of another ship.” He likened it to the 1980s video arcade game “Frogger.”
Entanglement in fishing gear presents a different problem. Fishers harvesting snow crabs, black sea bass or other marine species use different gear, while various fisheries are active at varying times of year, making the industry as a whole more complicated to regulate. One of Nowacek’s students has programmed a “virtual whale entangler” that models how various types of shipping gear affect whales. “We’ve been talking about gear modification – gear that breaks away” under pressure, Nowacek said, though getting industry to adopt it seems a way off yet.
Elsewhere, Whale Watch came up with a model to predict where blue whales will be, based on environmental conditions and data from tagged whales; ships can then be alerted to the risk and encouraged to avoid the area. Since Brown’s working group helped convince the IMO to move shipping lanes in the Bay of Fundy and establish the no-go zone in Roseway Basin, it relied on a 2012 study to come up with a plan to separate ship traffic and whales around the Panama Canal.
With more data, perhaps they can help prevent more ship strikes in the Gulf of St. Lawrence before it’s too late.