Saving Whales the Easy Way? Less lobstering could mean fewer deaths

A controversial new study argues that the U.S. lobster fishery in the Gulf of Maine could have the better of two worlds: less work to make the same profit and fewer whales dying as a result of getting tangled in lobster gear.

DEATH TANGLE. Remains of a North Atlantic right whale (top), entangled in lobster gear, lie on the beach. The same whale was photographed 7 months earlier (bottom) already snarled in the gear, which is one of the main perils to the highly endangered species. Only 350 right whales remain in the population, which isn’t increasing despite the ban on killing whales. WHOI; New England Aquarium

To create this better world, the lobster fleet should shorten its season and set out fewer traps, suggest biologists led by Ransom Myers of Dalhousie University in Halifax, Nova Scotia. The drop in effort shouldn’t undermine profits, they say, because the Canadian lobster fishery just across the border is thriving despite restrictions.

U.S. regulations permit lobster harvesting year round, while the Canadian season runs from the end of November through May. Overall, the U.S. fleet catches a third more lobsters but expends disproportionately more resources doing it.

For a given lobster harvest, the U.S. fishery uses 13 times as many traps as the Canadians do, the researchers say. Because tending extra traps requires more fuel and bait, a shorter, more efficient fishing effort could be as profitable, the team argues. In the Jan. 9 Current Biology, the biologists suggest a 6-month season and a 90 percent reduction in the several million traps currently permitted.

Although there’s no rule regarding season, U.S. lobster boats traditionally take almost all their catch during the 6 months of summer and fall, says lobster biologist Carl Wilson of the Maine Department of Marine Resources in West Boothbay Harbor. As for reducing the number of traps, “it’s an interesting idea, but the devil is in the details,” he says.

Limitations on the lobster fleet would be good news for the North Atlantic right whale, says coauthor Boris Worm, also of Dalhousie. The large, slow-moving, coastal whales have virtually vanished from the Atlantic coast of Europe. Only some 350 right whales remain along the North American coast.

For 70 years, laws have banned killing of the North Atlantic right whale, yet the population isn’t increasing, unlike that of a sister species, the South Atlantic right whale.

The northern whale might be stuck in a bad neighborhood—with heavy ship traffic, near-shore fisheries, and pollution—Worm says. “It has been called the urban whale,” he notes. Computer modeling has indicated that in such dire circumstances, losing even two or three adult females could send the already depleted population into a downward spiral.

According to previous studies, the top killers of right whales are ships that run into them and fishery rigging—often lobster gear—that accidentally entangles them.

Because migrating right whales travel through the Gulf of Maine in spring and fall, reducing the area’s lobster traps at those times would make the passage safer, says Worm.

The plan doesn’t impress Patrice McCarron of the Maine Lobstermen’s Association in Kennebunk. Regulations already require some low-tangle gear, and rules for more such gear are under consideration. Also, McCarron says, lobster-trap tenders don’t see any whales, so changing the industry “will not have any benefit to whales.”

Worm notes that migrating whales are difficult to spot and that scientists have incomplete information about routes.

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.

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