Gray whale sightings off the Palos Verdes Peninsula coast are at a 40-year low, according to local whale watchers.
Volunteers at the Point Vicente Interpretive Center in Rancho Palos Verdes, in fact, had counted 70 southbound eastern Pacific gray whales this season, including six newborn calves, as of Tuesday, Jan. 16, along with five northbound grays, according to expert Alisa Schulman-Janiger.
During the same period last season off PVIC, there were 125 southbound gray whales and 13 calves, along with five northbound grays, Schulman-Janiger, director of the American Cetacean Society/LA Gray Whale Census and Behavior Project, said during a Tuesday interview.
That’s a 44% decrease in the number of adult gray whales headed south.
The numbers were even smaller just a day earlier, Schulman-Janiger said. But the whale count got a bump on Tuesday when 11 southbound gray whales were spotted, along with a mother and her newborn calf about a half-mile to three-quarters of a mile offshore of the PVIC.
The gray whale migration season runs from around Dec. 1 to May 25.
Various reasons could account for the decline, Schulman-Janiger said, including shrinking ice pack, which shields food for the whales.
“Southbound migration might be running later than usual,” Schulman-Janiger said, “perhaps grays are lingering on their Arctic feeding grounds, or headed further north to feed.”
A “higher proportion of gray whales might also be using the preferred offshore migration path through the Channel Islands and out by Santa Catalina Island,” Schulman-Janiger said.
There has been an abundance of wildlife showcased off the Palos Verdes Peninsula coast in recent months. with migrating humpback whale sightings in November on their way to San Diego. And various killer whale species have been making rare appearances.
On Jan. 2, a newborn gray became the victim of eastern tropical Pacific orca whales.
There is no correlation, however, between the unusual sightings of orcas and the decrease in gray whale sightings, Schulman-Janiger said.
The gray whales are coming from their feeding grounds in Alaska and the orcas are coming up from Mexico, and normally target the common dolphin or bottlenose dolphins as their feeding source.
“They did kill our first gray whale calf, but that’s the first time they’ve ever been documented killing a whale in California, and this goes back to the first sighting that I know of in 2002,” Schulman-Janiger said. “That’s not a thing we typically see the whales from Mexico, the eastern tropical Pacific orca whales.”
But over the past seven years, there has been a significant decline in the gray whale count.
The National Oceanic and Atmospheric Administration Fisheries estimated there were 27,000 migrating gray whales in early 2016, but that dropped to about 14,550 in early 2023, a decline of more than 46%.
NOAA is responsible for protecting whales, dolphins, porpoises, seals and sea lions under the Marine Mammal Protection Act, which Congress passed more than five decades ago, according to its website.
There was an elevated number of eastern Pacific gray whale strandings in 2019 along the West Coast, from Mexico to Alaska, and because of this, NOAA defined it as an unusual mortality event under the Marine Mammal Protection Act.
A UME, according to the Marine Mammal Protection Act, is a “stranding that is unexpected; involves a significant die-off of any marine mammal population; and demands immediate response.”
A lack of food seems to be a contributing facor in such die-offs, according to a study by scientists from the University of Maryland’s Center for Environmental Sciences, which was published in the journal Science in the fall. That study was supported by the U.S. National Science Foundation.
“Fluctuating stocks of a shrimp-like creature living in the sediments of the Bering and Chukchi seas,” according to the NSF website, “are likely to have caused three major die-offs in the eastern North Pacific gray whale population since the 1980s.”
Among those is the UME that happened in 2019 — and is ongoing.
“The gray whale population has been reduced by up to 25% over just a few years,” according to the study.
The gray whales’ source of food is “sensitive to sea ice cover,” according to the NSF. The whales feed on the “shrimp-like creatures,” which eat algae that grows underneath sea ice.
“Less ice leads to less algae reaching the seafloor,” the NSF said. That reduces the whales’ natural diet.
“They had less food and therefore they became skinny and therefore they weren’t able to make a lot of blubber, and the blubber is what the milk comes from,” Schulman-Janiger said. “They’re not able to feed their kids and so that’s why you got skinny whales, stranded whales and fewer babies.”
NOAA is currently conducting a gray whale count at Granite Canyon, south of Carmel, before Big Sur.
In 2016, when NOAA counted 27,000 migrating whales, that was the highest estimate the organization had come up with in its history. But in 2023, it dropped to the lowest NOAA ever counted, Schulman-Janiger said.
“There was a big problem in 2019 and every year since then, there’s been concern like skinny whales, stranded whales, fewer calves,” Schulman-Janiger said. “And every year, it has gotten a little bit better, but it’s still bad enough that the population kept dropping.”
