This behavior leaves them vulnerable to boat strikes and entanglement in fishing lines, almost exclusively the cause of their deaths. There are so few North Atlantic right whales left in the world’s oceans – estimates hover around 400 – that many are known entities to the scientists who devote their careers to saving them. They often identify them by the patterns of callosity on their heads, raised tissue colored white by an infestation of cyamids, commonly known as “whale lice”. I mention Dragon, a 19-year-old female right whale spotted this year off the coast of Nantucket with a fishing buoy entangled in her mouth, dying. It’s long and painful.” George has watched whales struggle to survive horrendous ship strike injuries. He’s seen fishing rope embedded in the whales’ faces, cutting through bones, entire lips pulled off. “But he came back the next season, scarred.” Ruffian returned to Georgia waters another time, snow crab cables trailing behind him. They were known as the “right” and easy whale to hunt – docile, slow-swimming and huge – 52 feet long and sometimes weighing in just under 70 tons. Each winter pregnant females and other members of the species migrate 1,000 miles south to Georgia and Florida, the species’ only known calving grounds. Their coastal distribution places them in close proximity to largepopulation centers, and all the human activities that go with that, from commercial fishing and shipping, to pollution and military training. No one really knows how long North Atlantic right whales can live, because human activity has affected their life spans so drastically. “A species that most people have never seen is harder to convince others to save,” says Dr Erica Fuller, a veterinarian and a lawyer with Conservation Law Foundation in Boston, Massachusetts. “If you saw one, you’d be struck by how majestic they are.” Gallery: These images show the true impact of plastics on our oceans (Love Exploring) The whales are at risk any time fishing rope is left unattended in their habitat. These synthetic ropes can be set for weeks or months at a time, and require thousands of pounds of force to break loose from. It’s a terrible conflict of interest.” The real tragedy, according to Fuller, happened when the whales traveled into the Gulf of St Lawrence looking for food and, simultaneously, the snow crab fishery exploded. More than half of the known right whale population migrated into Cape Cod Bay in the summer of 2019, following their food source of phytoplankton. As they journey there and further northward toward Canada, they cross shipping lanes, putting them at risk of death by blunt force trauma and propeller cuts. The reduction in speed orders are lifted when no right whales are spotted, but detection mechanisms are faulty, and ship strikes have contributed to 30 deaths of rightwhales in the last three years. The right whale calf born to Derecha that was struck this calving season – its head sliced by the propeller of a vessel – is presumed dead. Right whales are vocal – when socializing in “surface active groups” they scream, blow, gunshot, upcall, warble and downcall. Passive acoustic tracking is an important component of a suite of whale-tracking measures, including aerial surveys and reports from fishermen. Currently there is no reliable, compassionate way to track the right whales with GPS, which would theoretically help boat captains avoid ship strikes. She recounts the time she spotted a right whale named Wart off the coast of Cape Cod, with a calf. If these changes force the whales into new habitats with greater human activities but fewer protections, the results could be disastrous. This is exactly what appears to be happening in the Gulf of StLawrence in Canada, where more than 20 right whales (5% of the existing population) have been found dead since 2017.
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