Saving Seafood

Entanglements in fishing gear stunting growth of right whales, study finds

June 4, 2021 — Entanglements in fishing gear, which have been among the leading causes of death of North Atlantic right whales, are likely also stunting their growth and causing the critically endangered species to reproduce less often, a new study found.

The research raises questions about the findings of a major report on the species released last month by the federal government and could have a significant impact on how it regulates the lobster industry, which has been the primary source of entanglements. The population of right whales has plummeted over the past decade by a quarter, with scientists estimating that fewer than 370 remain.

The long-term study, published Thursday in the journal Current Biology, estimated that a calf born in recent years was likely, when mature, to be about 3 feet shorter in length than those born in the 1980s. Entanglements have become more of a problem for whales in recent decades, as ropes have increasingly used synthetic materials and become stronger.

“Stunting of growth is a classic sign that a species is in trouble,” said Michael Moore, a senior scientist at the Woods Hole Oceanographic Institution and a coauthor of the study. “Smaller mothers are less capable of being successful breeders, because they have a smaller fuel tank and less lactation. That’s the biggest concern.”

He and other authors said the findings call into question a long-awaited report released last month by the National Marine Fisheries Service that found the lobster industry isn’t jeopardizing the survival of right whales. A federal judge last year ordered the agency to produce the report, known as a biological opinion, after rulingthat it had violated the Endangered Species Act by failing to reduce entanglements.

Read the full story at The Boston Globe

North Atlantic right whales are in much poorer condition than their Southern counterparts

April 27, 2020 — The following was released by the Woods Hole Oceanographic Institution:

A new study by Woods Hole Oceanographic Institution (WHOI) scientists and their colleagues reveals that endangered North Atlantic right whales are in much poorer body condition than their counterparts in the southern hemisphere. The international research team, led by Fredrik Christiansen from Aarhus University in Denmark, published their findings April 23, 2020, in the journal Marine Ecology Progress Series.

Using drones and a method called aerial photogrammetry to measure the body length and width of individual right whales in four regions around the world, the team compared body condition of individual North Atlantic right whales with individuals from three increasing populations of Southern right whales: off Argentina, Australia and New Zealand.

From aerial photographs, the researchers estimated the body volume of individual whales, which they then used to derive an index of body condition or relative fatness. The analyses revealed that individual North Atlantic right whales—juveniles, adults and mothers—were all in poorer body condition than individual whales from the three populations of Southern right whales.

“For North Atlantic right whales as individuals, and as a species, things are going terribly wrong,” says WHOI researcher Michael Moore, a coauthor of the paper. “This comparison with their southern hemisphere relatives shows that most individual North Atlantic right whales are in much worse condition than they should be.”

Read the full release here

WHOI Releases Report on Right Whale Threats, Solutions

April 1, 2019 — A new report has been released by the Woods Hole Oceanographic Institution which details the major threats facing critically endangered North Atlantic right whales.

The population for the species is estimated to be just over 400 and has suffered in recent years from high mortality rates with very few births.

The report indicates the whales are most threatened by fishing gear entanglements, vessel strikes and noise pollution.

WHOI Marine Biologist Michael Moore, who was a co-author of the report, says there has been a dramatic shift in the number of deaths caused by entanglements over the last decade.

Before 2010, 45 percent of right whale deaths were due to vessel strikes with 35 percent attributed to entanglements. Since 2010, entanglements have resulted in about 85 percent of right whale deaths.

“The entanglement rate has gone up and become more severe,” Moore said. “It used to be the animals would get entangled and scarred up and then be able to wiggle out of it or get disentangled, but now the entanglement mortality rate has also increased.”

Whale researchers are also concerned with the non-lethal effects of getting caught in fishing gear.

“Eighty-plus percent of the species show entanglement scars and 25 percent of them get new scars every year,” Moore said. “So the majority don’t die but they do have sub-lethal impact and really it comes down to stress of being entangled and pulling the rope through the water and traps too if they are involved.”

Read the full story at CapeCod.com

No calves as right whales return to Nova Scotia from Florida

May 30, 2018 — Only 16 whale sightings were reported anywhere south of Virginia this winter. The lack of sightings, coupled with at least 18 whale deaths reported in Canada and the United States between April 2017 and January 2018, leaves those interested in right whales concerned.

Scientists studying the critically endangered North Atlantic right whale logged another depressing statistic this winter.

In the more than 30 years scientists have tracked the movements of the whales between New England and Nova Scotia and the warmer waters off the Florida coast, this was the first time no calves have been sighted. That fact has only added concern to the growing sense of urgency after right whale deaths skyrocketed last year.

“Obviously you can’t tell a right whale it’s time to have a baby,” said Michael Moore, a senior scientist at Woods Hole Oceanographic Institution and director of its marine mammal section.

But Moore and many other right whale scientists watching the highly endangered population dwindle before their eyes are seeking answers to the deadly perils the animals face, including collisions with the ships that share their space, commercial fishing gear that tangles the whales, and a warming ocean that appears to be wreaking havoc with their food supply and changing their migration patterns.

Read the full story at the Daytona Beach News-Journal

 

Scientists study how marine mammals survive at great depths

April 30, 2018 — Whales, dolphins and seals have evolved to hunt prey deep in the ocean, an environment that would otherwise prove deadly to animals that depend on breathing air to live. Until recently, scientists believed marine mammals’ known physical adaptations protected them from the effects of such punishing depths.

But scientists were baffled by computer models that showed that, even with the known adaptations, 50 percent of animals studied still should have experienced the bends. Researchers concluded there must be some else going on.

A new study by the Woods Hole Oceanographic Institution and the Oceanographic Foundation of the City of Arts and Sciences in Valencia, Spain, may provide an answer. The study, funded by the U.S. Navy, found that deep-diving marine mammals use a physical adaptation — the collapse of one portion of the lungs — to block the flow of nitrogen into the blood and prevents the animals from getting the bends, the crippling release of nitrogen gas that can occurs when surfacing from dives deeper than 130 feet.

“If you get the conditions right, you can get a nice exchange of oxygen and carbon dioxide but block the nitrogen,” said Michael Moore, a WHOI senior scientist who specializes in the analysis of marine mammal mortalities. Moore is a co-author of the study, which was published April 25 in the journal “Proceedings of the Royal Society B.”

The mammals have other physical adaptations that help them survive the depths when they exhaust available oxygen in their lungs, including a high amount of proteins in blood and muscle that bind oxygen and a higher ratio of red to white blood cells. Their ribs and lungs can collapse under pressure without breaking and their airways are hardened bunkers that remain partially open to power the signals they use to locate one another and their prey.

Read the full story at the Cape Cod Times

 

Fate of the Lobster Fishery May Depend on Fate of the Right Whale

April 18, 2018 — The North Atlantic right whale was once seen as an inexhaustible natural resource. It was hunted for its oil and enriched New England. That ended one-hundred years ago, but the right whale’s numbers have never been the same. Now, the whales that are left are in direct conflict with the harvesting of another rich natural resource: lobsters.

About the time when the first crocuses start to bloom, the North Atlantic right whale comes back in numbers to feed in Cape Cod Bay, and researchers go out on the water to count them.

A research vessel from the Center for Coastal Studies is off the coast of Provincetown and coordinating with a crew in a spotter plane. There are so few whales left, the scientists can often identify individual animals.  They see two: Elf and Ruffian.

When commercial whaling ended in the 1930s, there were only about 100 North Atlantic right whales left in the world. Now that people weren’t killing them on purpose, their numbers slowly climbed, topping out at about 550 in the year 2010. Then something happened. Their numbers started to drop. But why? Their relatives, the Southern right whales, are doing fine.

Michael Moore is a biologist at Woods Hole Oceanographic Institution who has been examining dead whales for 30 years to figure out what happened to them. Moore says, “The two pieces that make the difference between the Southern right whale’s success and the Northern Atlantic right whale’s struggle has been vessel collisions and entanglement in fixed fishing gear.”

He says, in the southern oceans there are fewer ships and less fishing gear, and that has allowed Southern right whales to grow to a population of 15,000. There are now fewer than 450 North Atlantic right whales here off the coast of New England.

Read the full story at WCAI

 

To protect right whales, scientists propose major changes for lobstermen

February 20, 2018 — WOODS HOLE, Mass. — Without prompt action to reduce entanglements in fishing lines, North Atlantic right whales could disappear from the planet over the next two decades, scientists say.

In response, scientists here on Cape Cod are proposing a novel way to save the species — one that many New England lobstermen fear could destroy their livelihoods.

At a recent meeting with a host of skeptical lobstermen, scientists at the Woods Hole Oceanographic Institution presented the concept of ropeless fishing, a nascent technology that eliminates the need for the long, taut ropes that extend from millions of traps at the bottom of the ocean to their buoys at the surface. These ropes have killed many of the docile mammals.

“I want to see a profitable, sustainable lobster industry that’s not abusive to the animals,” said Michael Moore, director of the Marine Mammal Center at the Woods Hole Oceanographic Institution. “But what’s happening now isn’t working. We’re painfully and inexorably squeezing the life out of these animals.”

Over the past year, at least 18 right whales have died — a grave blow to a species with only about 450 left in the world and just 100 breeding females. Scientists fear they’re not reproducing fast enough and could face extinction as soon as 2040.

The problem, Moore and his colleagues say, is that most fatalities appear to be the result of right whales becoming entangled in fishing lines. In a federal survey of right whale deaths between 2010 and 2014, scientists found that 82 percent died as a result of entanglements. The rest died from ship strikes.

Read the full story at the Boston Globe