
North Atlantic right whale mother and calf. Public domain photo
After a year with at least 17 deaths and a dismal breeding season, things are looking bleak for the North Atlantic right whale, one of the world’s most endangered large whales. The whales’ food is moving north and so are the gentle giants, into waters rife with fishing industry activity. According to a new paper out Monday in Oceanography, saving the species from extinction will require increased monitoring of these creatures, and finding new ways for fisheries and right whales to coexist sustainably.
Rising global temperatures are causing a poleward shift in species distribution. Range shift velocities are higher in the marine environment, with observed rates of 30–130 km per decade. Both protected and exploited species will be at risk if marine species management policies are not structured to anticipate these range shifts. The 2017 mass mortality event of the North Atlantic right whale showcases the detrimental impact of unanticipated climate-mediated behavior in a species protected by geographically and seasonally fixed policies. Based on the results of a demographic capture-recapture model, right whales may face extinction in fewer than 30 years unless protective policies are expanded to cover their shifting distribution. Increased support of long-term monitoring programs paired with environmental modeling research is critical to developing more proactive conservation management strategies and preventing further ecological crises. From Oceanography
Traditionally, North Atlantic right whales roamed the waters of the Gulf of Maine and the Scotian shelf (near the island of Nova Scotia) in the summer and fall to forage for their food—small aquatic crustaceans named copepods. Researchers believe warming oceans may be driving copepods northward and that the whales are following suit.
Here’s the rub: In 2017, North Atlantic right whales occupied, in large numbers, the waters of Canada’s Gulf of St. Lawrence. This is an area that, until recently, lacked the regulations needed to protect the North Atlantic right whale from ship strikes and entanglement in fishing gear.
“It’s not so much that the whales weren’t finding the food and then they were starving to death,” Erin Meyer-Gutrob, post-doctoral scholar at University of California Santa Barbara and lead author of the paper, told Earther. “It’s that when they had to go looking for food, they faced a greater risk of human caused mortality.”
Last year saw an alarming dieoff of North Atlantic right whales, something researchers refer as an “unusual mortality event.” Their carcasses littered the shores of the east coast—12 in Canada and 5 in the United States. Necropsies revealed that most of the animals died from blunt force trauma or entanglement issues. This brings the North Atlantic right whale’s fragile population to an estimated fewer than 500.
It gets worse. While the North Atlantic right whales have averaged about 17 births per year for the past three decades, researchers only saw 5 last year. The 2018 calving season was particularly dismal: no new North Atlantic right whale calves were found. Some researchers attributed these plummeting birth rates to a shift in food supply. When prey is limited, right whale females have trouble building up the blubber layers that they need in order to get pregnant, sustain the pregnancy, and then nurse their calves.
“If we don’t take significant and immediate action, the whales we know today may be the last of their kind,” Francine Kershaw, project scientist at the NRDC’s Marine Mammal Protection Project and Oceans Program who wasn’t involved with the new paper, told Earther via email.
The new paper calls for increased surveillance of North Atlantic right whales and their food supply to keep the species afloat. “We can’t protect waters unless we know that the right whales are there,” Meyer-Gutbrod told Earther. “The best way we can do that is by getting more eyes and ears on the water.”
According to Meyer-Gutbrod, crafting policies that protect the North Atlantic right whale requires careful monitoring of their whereabouts—a difficult feat in a vast ocean. Protective policies could also disrupt fishing industry activity. Thus, to validate the high cost of implementing them, researchers should provide evidence that the right whales are, in fact, going to be in that region.
Along with surveillance from boats and planes, some researchers are also working on an underwater listening array—remotely operated vehicles equipped with underwater microphones to listen to the right whales.
Though monitoring distributions of wildlife and their prey is crucial in predicting future conflict areas, “it is unlikely we’ll be able to predict all of the changes in our oceans with 100% accuracy.” Kershaw said. “Therefore, reducing or mitigating known stressors at the source will prove to be the most protective approach.”
Despite the troubling year the North Atlantic right whales have been through, there’s an inkling of a silver lining. The 2017 mass mortality event and poor calving season have galvanized researchers, policymakers, and activists into action. Canada has already implemented policies in the Gulf of St. Lawrence to avoid a repeat of 2017: ships over 20 meters (65 feet) in length have to slow down to 10 knots; the snow crab fishing season will be moved around to minimize the overlap between fishing gear and the animals.
On Friday, which was World Oceans Day, Congress stepped up with the SAVE Right whales Act of 2018, a bill intended to fund conservation programs aimed at rebuilding North Atlantic right whale population.
“If we don’t take immediate action, the storied North Atlantic right whale could go extinct in our lifetime,” said Senator Cory Booker (D—New Jersey), one of the bill’s co-sponsors. “We have a responsibility to find and implement solutions that will help protect endangered species for generations to come.
–From Earther
Categories: AtlanticOcean, Conservation, Engangered Marine Species, Entangled Marine Mammals, Gulf of Maine, Marine Mammals, North Atlantic Right Whale, Possible Extinction, Warming Oceans, Whales
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