Editor’s note: The consistently disturbing news of marine mammals dying off or stranding in mass appears to be a global event. Gray whales are an iconic species that have survived throughout the centuries, including the great whale hunts of the 1800s. This editor wrote about the gray whale’s obstacle course in 2010: A North Pacific Gray Whale Obstacle Course.
The following report is from today’s Orange County Register:
Thirty gray whales have died along the West Coast since the start of the year, a number that has experts concerned as they try to determine the cause of the spike.
So far, 21 dead whales making their migration from Alaska to the warm water lagoons in Mexico and back have been found along California, one off Oregon and eight off Washington, said Justin Greenman, assistant stranding coordinator for the National Oceanic and Atmospheric Administration’s Stranding Network.
This year already represents the third-largest gray whale mortality total on record, when compared the first four months of the year, and it’s not even the peak stranding season, which is typically late April through June, he said.
A dead whale on March 21, 2019, found near the Port of Long Beach. The whale is just one of 30 found since January along the West Coast. (Photo courtesy: NOAA)
Eight whales have been found along the Los Angeles County coast, some floating near the Port of Los Angeles. One whale, in early March, washed up on the rocks near San Pedro and another, about a week later, was found just offshore in Hermosa Beach.
One whale was found off of Orange County, and two off San Diego.
Northern California, likewise, has had a large number of whale standings, including eight in the San Francisco Bay, one in Mendocino County and one in Humboldt County.
Local NOAA authorities are coordinating with counterparts in Mexico and Alaska to solve the mystery of the strandings, which are on pace to match 2000, the worst year on record, when more than 80 gray whales died.
Skinny whales, low calf counts
One clue to the mystery: Migrating gray whales have been unusually skinny, suggesting something is amiss in their food chain.
Alisa Schulman-Janiger, who runs the Gray Whale Census & Behavior Project from the Point Vicente Interpretive Center on the Palos Verdes Peninsula, said she noticed something was wrong months ago as she watched the whales passing the coastal cliffs on their way to the lagoons in Mexico.
“There’s definitely something going on,” she said. “We had more skinny whales than I’m used to seeing … they were emaciated, skeletons with skin, basically.”
Something else was odd, she said. The southbound whales were late, not showing up in the hundreds in December as they had in recent years.
Then came the strandings, dead whales dotting the coast.
Schulman-Janiger contacted researchers in Mexico, who said the calf counts at the lagoons there were extremely low, about a third of what they were the year before. Sixty percent of the whales were showing up skinny, they reported.
“Think of a woman with anorexia — you aren’t going to be able to get pregnant or sustain the pregnancy,” she said. “Or the mom can’t nurse because she doesn’t have blubber.”
This could be one reason so many juvenile whales have been appearing in the Los Angeles Harbor — to snack in a shallow-water habitat. It’s the same in San Francisco, Schulman-Janiger said, where whale experts have reported at least five skinny whales feeding in the harbor.
“Everyone is noticing skinny whales, everyone is noticing dying whales,” she said.
Schulman-Janiger said it’s similar to what she observed in the 2000 season: whales late to start their migration; skinny; feeding in unexpected places; and dying, in what was termed an “unusual mortality event.”
Greenman said he’s been in touch with NOAA national headquarters and researchers in Alaska to find out what’s happening at the food source, where whales spend their summers feeding.
Schulman-Janiger worries there’s an “ecosystem crash,” with warmer-than-normal waters in Alaska melting ice and having an impact on their food.
“They probably stayed longer to try and find food. And when they got to Mexico, it was a quick turn-around,” she said. “Mom needs to go get food. She’s not going to hang out socializing, she’s going to go get food.
“If something is wrong with them, something is wrong with the ecosystem.”
Examining dead whales
The 30 dead whales NOAA is reporting for 2019 along the West Coast represents just the deaths that officials know about. There could be some farther out to sea that no one has seen, or others that lifeguards towed out to sea without informing NOAA.
Experts study the dead whales, sampling the tissue in an effort to determine the cause of death. So far, authorities have been able to examine about half of the 30 whales.
For the most part, what they’ve found, are emaciated whales with empty stomachs and low muscle content, Greenman said. In one case, however, the cause of death appeared to have been a vessel collision and in another, it could have been health issues related to a prior entanglement, he said.
“There was a period where we had seven animals in six days,” Greenman said. “I know we have a couple whales right now waiting for the team to logistically get to them.”
Categories: Climate Change, Condition of Oceans, gray whales, Pacific Ocean, Unusual Mortality Event, Warming Oceans, Whales
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