Partial disentanglement of right whale #3125 on 8/2/19. Final cut. CCS, NOAA permit #18786-03.
Right whale consortium urges action to save species
PORTLAND, MAINE — Right whales continued their precipitous march toward extinction last year.
In presenting the annual right whale report card, Heather Pettis of the New England Aquarium’s Anderson Cabot Center for Ocean Life told attendees at the North Atlantic Right Whale Consortium’s annual meeting in Portland Thursday that the world’s most endangered great whale experienced another population drop in 2018 to 409 individuals.
That estimate was down from 451 in 2016 and 411 in 2017.
Right whales feed on the surface. They move slowly, seem oblivious to ships and are hard to see. Ships were once the main cause of right whale deaths, but have been overtaken in recent years by entanglement in fishing lines, particularly the vertical lines that run from a surface buoy to a lobster pot.
“Yet another year of decline for right whales,” said Consortium Chairman and Woods Hole Oceanographic Institution researcher Mark Baumgartner.
While right whale numbers climbed from 314 individuals in 2000 to 482 by 2010, “we’ve eroded half those gains,” Baumgartner said.
Baumgartner saw a grim example of how fast extinction can happen in the vaquita, a tiny porpoise in the Gulf of California that is caught inadvertently by Mexican gillnet fishermen illegally trying to land totoaba, another endangered species. The vaquita went from 500 in 1997 to between six and 22 individuals today.
“When you have a very small population, it can get away from you very fast,” Baumgartner said.
The right whale population is so small that the National Marine Fisheries Service put the number of animals that can be killed by humans each year without impacting the species recovery at less than one. So far in 2019, 10 right whales have died, while three died last year and 17 died in 2017.
“These are detected mortalities,” said Pettis, who also serves as the consortium’s executive administrator. “This is the best-case scenario, the reality is much worse.”
In recent years, possibly chasing food, rights whales have shown up in Canadian waters not accustomed to seeing them and with virtually no protections in place. Since 2015, 25 dead right whales have died from entanglement in fishing gear and ship strikes, mainly in the Gulf of St. Lawrence.
The deaths have Canadian officials scrambling to find solutions.
“It was very clear this had to stop,” said Tonya Wimmer, a marine mammal biologist and the director of the Marine Mammal Response Society of Nova Scotia. Wimmer’s team performed some of the necropsies on the nine dead right whales found in Canada this year.
“The teams needed it to stop too. It was getting to be depressing,” she said.
With extinction on the horizon, New England states agreed in April to craft measures that would result in a 60% reduction in fishing mortality by lobster pots on right whales. The meeting of the Atlantic Large Whale Take Reduction Team, a NOAA advisory group, led to draft proposals by Massachusetts and New Hampshire to reduce the number of vertical lines by 30% and to use rope with a 1,700 pound breaking strength that large whales could break through without getting entangled.
Rhode Island proposed an 18% reduction in the number of lines. Maine, with over 3 million traps and 4,500 permitted lobstermen, is the largest lobster fishery by far. At the time, it appeared to agree to a 50% reduction in the number of vertical lines and the use of breakaway rope, but later withdrew from the agreement.
Patrice McCarron, executive director of the Maine Lobstermen’s Association, told the consortium Tuesday that they felt that the fisheries service had not been accurate in assessing the 60% reduction. She said data showed few confirmed cases of verified death by entanglement in lobster gear and suggested that gillnet gear, large panels of nets that float upright like a fence and are anchored to the bottom, was more to blame.
“The 60% reduction was too high for our fishery,” she said Tuesday.
The fisheries service is working on new regulations to achieve that reduction and the states all have to submit plans to the agency that accomplish that, said Sean Hayes, the chief of protected species at the Northeast Fishery Science Center.
But McCarron said the agency should be looking more closely at other fisheries like gillnets and the shipping industry, which has been responsible for most of the Canadian deaths.
“Entanglement rates went up in the last decade and seem to be the prevailing cause of death,” countered Scott Kraus, a senior scientist with the Anderson Cabot Center and the incoming consortium chair.
Kraus noted it was hard to confirm what type of gear was responsible in most whale deaths, but the evidence of entanglement was strong, with 83% of right whales showing scars from line. Evidence also shows that lobster lines were by far the most prevalent in the ocean, he said.
“The entanglement risk is everywhere,” he said.
Amy Knowlton, gear research specialist for Anderson Cabot, said it was time to stop arguing over whose gear was causing the problem.
“We have to stem this tide of death and destruction,” she said, arguing that entanglements were occurring everywhere and involved all fishing gear using anchored vertical lines. The data showed that closures intended to protect whales were not working as they frequently moved out of protected areas, or they were instituted too late. Plus, determining where whales were being entangled was difficult, especially since large areas of the Maine coastline were exempt from federal whale protection measures.
Knowlton proposed that breakaway links developed by South Shore lobstermen that separate at 1,700 pounds, which is strong enough to haul gear but weak enough that it would separate when encountered by a whale, be used in all fixed gear fisheries in all areas.
This, she said, could be a stopgap measure until scientists developed a ropeless buoy system that was dependable and affordable.
“Clearly the trajectory is alarming,” said Philip Hamilton, a research scientist who manages the whale identification data base at the New England Aquarium.
But Hamilton noted the species had a big recovery in the early 2000s.
“We just have to stop killing them,” he said.
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