Menu Bar

Home           Calendar           Topics          Just Charlestown          About Us
Related Posts Plugin for WordPress, Blogger...

Monday, December 11, 2017

Save the whales!

Already on Brink, Right Whales Are Pushed Closer to the Edge

North Atlantic right whales are one of the world’s most critically endangered large whales, but if you’re lucky, you can still see them: a mother nursing her newborn in the warm waters off the Georgia or Florida coast, their only known calving grounds; right whales socializing and feeding in the fertile waters of Cape Cod Bay, sometimes within sight of shore; whales — black, 50 feet long, and weighing some 100,000 pounds — rising through the water in the Bay of Fundy or the Gulf of St. Lawrence, the northern end of their thousand-mile-plus migration route.


For a few decades, the math for North Atlantic right whales seemed to be working out, and the whales appeared to be experiencing a tentative recovery. Between 1990 and 2010, their numbers inched up from 270 to 483 whales — a slow growth rate, only 2.8 percent per year, but growth nonetheless.

But beginning in 2010, the tiny gains in their numbers began eroding. And now a new analysis by biologist Richard Pace from NOAA’s Northeast Fisheries Science Center and his colleagues provides stark confirmation of what many had already begun to suspect

The numbers are again heading down, threatening the whales’ very existence. The primary driver: whales becoming entangled in fishing gear and being struck by ships. Pace’s analysis found that North Atlantic right whale numbers dropped 5 percent from 2010 to 2015. 



The decline continued in 2016, and this year, observed losses are almost double those of 2016, reaching a record high. As of this month, at least 48 North Atlantic right whales have been killed since 2010, a 9 percent decline of this already small population.

“Science can be complicated, but not in this case,” says Charles “Stormy” Mayo, director of the Right Whale Ecology Program at the Center for Coastal Studies in Provincetown, Massachusetts. “It’s a simple equation: the number of right whales born every year minus the number that die.” 

Commercial whaling had decimated North Atlantic right whales by around 1750: their pre‑exploitation numbers are estimated to have ranged from 9,000 to 21,000 whales. This species was “right” to exploit because it swam close to shore, contained high yields of baleen and oil, and its thick blubber kept whales afloat after they were harpooned. Their centuries-long slaughter has rendered them rarer than endangered mountain gorillas, black rhinoceroses, and giant pandas. 

Now, because their numbers are already so low, seven years of losses are tipping the balance for the North Atlantic right whale away from recovery. “It’s not like me to do this,” says Mayo, “but I’m starting to use the word extinction here. It’s grim.”

For an animal protected under the U.S. Marine Mammal Protection Act and the Endangered Species Act, this precipitous decline is a disappointing, tragic failure, one that could have been averted had regulators taken more robust action to reduce mortality. 

In a letter last month to the U.S. Department of Commerce, 16 scientists representing the North Atlantic Right Whale Consortium noted that the primary causes of growing right whale mortality are collisions with ships and entanglements in fishing gear. 


The dire condition of North Atlantic right whales (Eubalaena glacialis) contrasts sharply with the state of southern right whales (Eubalaena australis)

Following the end of commercial whaling, right whales in the Southern Hemisphere rebounded to 15,000 animals, their populations growing about 6 percent annually. While North Atlantic right whales migrate through the busy shipping lanes and fishing gear of an industrialized ocean, their southern cousins swim through far less congested waters, dying of old age in their 80s. 


Head of Bight, in south Australia, is the country’s largest right whale calving ground. In 27 years of right whale research there, scientists recorded no deaths from ship collisions and only one from entanglement.


Biologist Peter Corkeron, co-author on the Pace paper, began studying whales as a post-doctoral student at the Head of Bight. He remembers 18 right whale calves born there in 1991, while in United States waters that same year, 17 were born. 

Today, right whales at the Head of Bight are in the midst of a baby boom, with researchers and whale watchers celebrating the birth of a record 81 calves in 2016, compared to a dismal five births in the U.S. last year.


Given the perilous state of northern right whales, U.S. government scientists calculated that humans could kill no more than one whale each year without jeopardizing the future of the species. 

From 2010 to 2014, however, the number of known human-induced right whale fatalities climbed to between five and six whales per year. (In that five-year period, entanglements in fishing gear accounted for 80 percent of serious injuries and deaths to right whales.) 


This year, the number of deaths skyrocketed. Witnesses have so far recorded an unprecedented 16 right whale deaths in 2017. At least five whales in the Gulf of St. Lawrence were hit and killed by ships. 

The heavy traps and ropes of snow crab gear killed at least one other and seriously injured five. In the U.S. in 2017, at least four, perhaps five, were killed by ships and at least five were entangled in fishing gear. Necropsies for the other deaths are pending. 


The number of whales entangled in fishing gear is rising. Biologist Amy Knowlton of the New England Aquarium, studying whale entanglements between 1994 and 2010, has found that 85 percent of right whales are snared by fishing line at least once in their lives, more than half at least twice, and more than 160 individuals entangled between four and as many as seven times. 

Severe injuries — wounds that cut into blubber, bone, and muscle — are also rising, and researchers are seeing more whales wrapped in fishing line and lobster gear. The only years Knowlton’s team hasn’t observed serious entanglements are those before 1993.


According to the Atlantic States Marine Fisheries Commission, between 1982 and 2013, 1 million additional lobster traps were deployed in the Gulf of Maine lobster fishery, bringing the total to more than 3 million. That’s a lot more rope in the water. Further, newer, stronger, rope became available in the 1990s, and it’s catching and killing whales. 

Scientist Jooke Robbins at the Center for Coastal Studies found that 25 percent of seriously entangled whales dragging fishing gear die within a year of their entanglement.


The numbers of right whale deaths attributed to fishing gear entanglement and vessel strikes, as disconcerting as they are, severely understate how many whales humans kill. For every whale known to die from an entanglement or a ship strike, there’s an almost equal number whose cause of death can’t be determined. 

Further, whales migrate through vast swaths of ocean, making it impossible to locate every dead whale. “It’s really important to realize that the number of dead whales we find is a minimum,” says Mayo. “For every dead whale we find out on the continental shelf, there may be one or two others we don’t see.” 


However many whales die prematurely each year, females bear the brunt; within three years of a severe entanglement, 44 percent of males survive, but only 33 percent of females do. 

As North Atlantic right whale numbers began dropping, Pace and Corkeron found females dying faster than males: Males declined by 4 percent, females by 7 percent, leaving, by 2015, three males for every two females and a dramatic difference in life expectancy. 


Southern right whales can live 80 or 90 years; North Atlantic right whale males, 85. Two-thirds of North Atlantic right whale females die before reaching 30. Almost all are gone by age 40. Knowlton has found that within three years of a severe entanglement, only 33 percent of females survive.


Today, slightly more than 100 reproducing females remain. Births can no longer keep up with deaths. In 1980, a female North Atlantic right whale lived long enough to bear five or six calves. Today, their short lives make that less likely. 

Northern right whales once gave birth every three or four years, but in recent years that interval has increased to more than six. “A lot of female whales,” says Knowlton, “may never calve again.”


Wildlife research veterinarian Rosalind Rolland, also from the New England Aquarium, and her colleagues found — based on the abundance of skin lesions, concentration of whale lice around blowholes, accumulation of blubber, and other factors — that in the last 30 years, the overall health of right whales has been declining. 

Assessing individual whale health on a scale of 100, they found that female right whales with scores below 67 don’t bear calves. Preliminary results from a new study show severely entangled females not giving birth. 


In a recent paper, Scott Kraus from the New England Aquarium and other scientists concluded that “there is no evidence that current fishing regulations have been effective at reducing mortality.” 

Current restrictions — requiring fewer vertical buoy lines, weak links on some lines to allow some whales to more easily break away, and seasonally closing some of the lobster fishery — have failed to lower the number of whales killed every year.


The double jeopardy of fewer births and more deaths is driving scientists and conservationists to fight for tighter, long-overdue restrictions on fishing gear in the territory of North Atlantic right whales. 

The National Marine Fisheries Service, in its October 2017 five-year review of the recovery status of the North Atlantic right whale, concluded that “progress toward right whale recovery has regressed.” 


Last month, the North Atlantic Right Whale Consortium (NARWC) urged the Department of Commerce to take “immediate action to prevent right whales from declining further toward extinction.”


Specifically, the scientists urged the government to take “bold and swift” action to reduce fishing gear entanglements and ship strikes. This could include modernizing the lobster fishery with traps that don’t use vertical ropes, and requiring lobstermen — with few exemptions — to use rope with a breaking strength of 1,700 pounds or less, which could sharply reduce life‑threatening entanglements.

Another option is to substantially expand seasonal closures of fixed‑gear fisheries until the whales recover.

Rerouting shipping lanes and seasonally requiring large ships to slow down in designated areas frequented by right whales has dramatically reduced the frequency of ship fatalities. But nine ship-strike fatalities in 2017 show that it may be necessary to expand the number of areas where ships are seasonally required to slow down to 10 knots and to expand the mandate to include ships smaller than 65 feet. 

Mark Baumgartner, NARWC chair, calculated how swiftly the National Marine Fisheries Service and the fishing industry must act. Given the number of breeding females, their share of the population, and their share of the deaths, he calculated that if the death rates since 2011 continue, few reproducing females will be left in 20 years.

That’s not a lot of time, but it’s enough if regulators act quickly. “It’s not magic,” says Corkeron. “We’re not looking for miracles. We need to save enough reproducing females to do a little better than we were doing before the slide. It’s possible.”

After 20 years, U.S. the National Marine Fisheries Service has failed to lower the human-caused incidental deaths of right whales below the threshold required under federal recovery plans. 

Consequently, in October and November, two coalitions of conservation groups filed notices of intent to sue, alleging the agency is failing to adequately regulate the lobster fishery to protect right whales, and that in proposing to reopen more than 5,000 square nautical miles of fishing grounds, it’s failing to ensure that further harm won’t come to right whales.


“The loss of one more whale could jeopardize their very existence,” says Erica Fuller from EarthJustice, co-counsel with the Conservation Law Foundation on two of the lawsuits. “Changes need to be made and we intend to take every step necessary to protect this majestic species before it is too late.” 

Deborah Cramer is the author of The Narrow Edge—a firsthand account of the harrowing, transcontinental voyage of the Red Knot. She lives in Gloucester, Massachusetts, and won the 2016 Reed Award for her environmental writing.