Critically endangered species spotted just north of San Francisco
A critically endangered North Pacific right whale was observed off the coast of Point Reyes National Seashore in a rare recent sighting. The rare sighting of North Pacific right whales, a critically endangered species of blue whales near Cordell Bank National Marine Sanctuary, was witnessed by researchers from the Greater Farallones and Cordell Banks national marine sanctuaries. The researchers were conducting a CDT, which measures the conductivity, temperature, and depth of the water when the animal came within 650 feet of them. The animal was so close that it could see a cluster of callosities on its head or large patches of toughened white skin. This sighting was the first time the species had been spotted in over a year in the Bay Area. The last recorded observation was in March 2023. The species was listed as endangered in 1970 due to historic whaling practices that decimated their numbers. The age and sex of the individual recently seen have not been confirmed.
公開済み : 10ヶ月前 沿って Amanda Bartlett の Science
“We clearly saw the V-shaped blow, no dorsal fin, all black, very broad,” Roletto, the research coordinator for the Greater Farallones and Cordell Bank national marine sanctuaries, told SFGATE in an email. “It was darker than a humpback and not the shape of a humpback.”
Still, about one to six blue whales had emerged each day of the trip, and it seemed early in the year for so many to be in the area. But the researchers never anticipated what they would encounter next.
Moments before the sighting, they were conducting a CDT, which measures the conductivity, temperature, and depth of the water. The boat wasn’t moving when the animal came within about 650 feet of the team, Roletto said — so close that they could see a cluster of callosities on its head, or large patches of toughened white skin that are telltale identifiers for the species.
“It would blow, sink, blow again, about 2-3 times, then sink down for a few minutes” as the gusts of wind howled, propelling the strong currents, Roletto said. The animal seemed to be “resting” and did not even lift its head in response to the movement of the nearby ship, even after she asked the captain to turn around out of fear of getting too close and hitting the animal.
It was the first time the elusive species had been spotted around the Bay Area in more than a year. The last recorded observation was in Monterey Bay in March 2023, at the time the 18th confirmed sighting of the species off the coast of California since 1955, Colleen Talty, a research biologist for Monterey Bay Whale Watch and the California Killer Whale Project, previously told SFGATE.
“Local sightings of North Pacific right whales are incredibly rare,” Giancarlo Rulli, a spokesperson for the Marine Mammal Center, told SFGATE. The few others reported were off Half Moon Bay in April 2022, Anacapa Island in May 2017, and La Jolla in April of that same year, according to Monterey Bay Whale Watch. Some years, scientists fail to observe a single North Pacific right whale.
The age and sex of the individual recently seen near Cordell Bank National Marine Sanctuary have not been confirmed, but North Pacific right whales can grow up to 64 feet long and weigh up to 100 tons. The animals were listed as endangered in 1970 due to historic whaling practices that decimated their numbers. The species got its name from commercial whalers who called it the “right” whale to hunt because they are known to swim slowly and float to the surface of the water after they die, per NOAA Fisheries. In the early 1800s, hunters killed off 80% of the population in a span of two decades, and though the species started to experience a gradual recovery by the 1960s, illegal whaling in the Soviet Union likely brought the population down to its current size, Jessica Crance, a marine biologist with the NOAA’s Alaska Fisheries Science Center, previously told SFGATE.
Threats such as fishing nets, vessel strikes, oil spills and ocean noise continue to imperil the species, but so little is known about their tiny existing population that experts are still trying to figure out where their migratory routes and breeding grounds are. Recent sightings included healthy whales that mostly lacked entanglement scars, and the individual seen in 2017 was a juvenile, making scientists optimistic that the animals were continuing to reproduce and a recovery in the population was possible.
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