Death came quickly for the calf. For the adult nicknamed Cottontail, it took months.
There are fewer than 375 North Atlantic right whales left. The two leading threats pushing them closer to extinction are entanglement in commercial fishing gear and being hit by ships and boats.
Within two weeks last month, the Southeast coast saw right whales die from both, losses that overshadowed an otherwise encouraging winter calving season.
Cottontail was a 12-year-old male cataloged as right whale no. 3920. In October, he was seen trailing hundreds of feet of fishing rope off Massachusetts. Right whales swimming past buoy lines linked to gillnets and lobster and crab traps – mostly in New England and Canadian waters – often inadvertently snag the ropes and end up pulling lines and sometimes even traps with them.
The heavy, synthetic ropes can saw into flesh and bone and drain a whale’s energy. Some whales shed the lines. But many don’t. For them, too often the result is a slow death from infection and starvation.
And entanglements aren’t rare. Reports suggest that about eight in 10 right whales bear scars from being entangled.
Dead Whale Swimming
A Center for Coastal Studies disentanglement team managed to cut 90 feet of line off Cottontail near Nantucket, Mass., last fall. But the prognosis wasn’t good. The rope was still wrapped tightly around his upper jaw and coming out both sides of his mouth.
Things looked worse after he swam more than 1,000 miles to the species’ only known calving grounds off the coast of Georgia and north Florida. Spotted near Sebastian Inlet, Fla., on Feb. 18, Cottontail was emaciated (video).
Agencies rallied for another try at cutting away the rope. But Cottontail disappeared. Within days, he was dead. The crew of a whale survey plane saw his shark-ravaged carcass off Myrtle Beach, S.C., in late February.
There’s hope that a NOAA analysis will show where the rope came from. Yet even when Cottontail was swimming at Sebastian Inlet, there was actually little hope for him.
Clay George, a senior wildlife biologist who leads Georgia DNR’s work with right whales, said the rope was embedded in the whale’s upper jaw and woven through the baleen in his mouth.
“We’ve seen that before: It doesn’t tend to end well for the animal. He probably died from a combination of running out of steam and potentially also infection.”
A Life Cut Short
In January, researchers photographed the first calf of right whale no. 3230 off Amelia Island, Fla. A month later, the toddler-age male, having grown to nearly 2 tons, washed up dead on a beach near St. Augustine.
His head and back had been scored by boat propellers. “The cuts were deep,” said Tom Pitchford, a Florida Fish and Wildlife Conservation Commission wildlife biologist who helped with the necropsy.
The props sliced through bone in the calf’s mouth and into a network of blood vessels. The back wounds laid open skin, blubber and muscle, even penetrating the lung cavity. The impact also left bruises, broken ribs and a fractured skull. A state investigation into the boat strike reported no violations. A NOAA probe is ongoing.
The calf’s mother, named Infinity, was seen swimming days later with fresh cuts on her side consistent with a vessel strike. Pitchford said the wound patterns suggest the mom and calf were swimming together at the time of impact. “Side by side, with the calf on the mom’s hip, if you will.”
Researchers know more about this incident because the captain of the 54-foot sportfishing boat immediately reported the strike (the boat began taking on water and had to be grounded). But it also shows how recreational vessels shorter than those 65-feet or longer – which are regulated by seasonal speed limits – can also be dangerous for right whales.
Counting the Cost
The strike that seriously injured a calf in Georgia waters last winter possibly involved a boat less than 65 feet long. That calf has not been seen since.
Nor has another entangled whale from this winter: a 33-year-old male photographed with fishing rope wrapped around its tail.
Which means NOAA’s Unusual Mortality Event for North Atlantic right whales will likely continue. Infinity’s calf was the 33rd right whale found dead in U.S. and Canada since 2017. Add another 14 live but seriously injured whales and the designation covers more than 10 percent of the known population.
Meanwhile, a new study says that the right whale deaths documented represent only a fraction of the number that have died.
Two weeks in February provided grim reminders of that toll and two primary reasons for it.
Learn more about how you can help right whales.
Featured Image: Cottontail swimming off Indialantic Beach, Fla., on Feb. 18. Photo taken under NOAA permit 18786. Photo credit: Joey Antonelli/Florida FWC.