Should We Be Alarmed More Whales Are Washing Ashore in the Bay Area?

As part of our series Bay Curious, we’re answering questions from listeners and readers. This story was produced in collaboration with iSeeChange.

Bob Hutchinson is a regular at Sharp Park Beach in Pacifica, where he takes walks, rides his mountain bike and sometimes goes fishing. Usually Hutchinson knows what to expect, but a few months back, he started seeing things on the beach that he hadn’t noticed before.

Starting in April, an alarming number of dead whales began showing up -- three around his beach alone. And the same thing started happening on other beaches nearby. He recently sent in this question:

“Why have there been three dead whales washed up in Pacifica, California in the last four months, when in 35 years of living here I’ve only seen one or two?"

Shortly after Hutchinson sent in this question, another whale turned up. This time it was a dead fin whale, pinned under a dock on Alameda Island across from the Port of Oakland. According to the Marine Mammal Center in Sausalito, that whale was hit by a tanker ship and probably plowed into the Bay.

Through the summer and fall, gray whales, humpbacks, fin and sperm whales migrate north from Mexico to Alaska by the thousands. Experts say the current collisions and strandings are happening because there are so many whales off the coast this year.

"It's not unusual for gray whales to strand,” said Izzy Szczepaniak, a naturalist with Golden Gate Cetacean Research. “But the fact that we had a killer whale, a sperm whale, a pygmy sperm whale, a humpback whale and gray whales -- that's what's unusual."

According to the National Oceanic and Atmospheric Administration, 28 whales have died in California so far this year, about a third more than normal. The causes of death are mixed. For example, they're malnourished, they get caught in fishing gear or they're killed by orcas. But the number that have been hit by ships is up slightly, like the fin whale in Alameda. According to Nate Mantua, a researcher at NOAA’s Southwest Fisheries Science Center in Santa Cruz, the reason those collisions are happening can be traced back to what’s in the water.

"The ocean is exceptionally warm,” Mantua said, “probably warmer than at any time in our historical records that go back to 1900 or so.”

The warm water he described is called “the blob.” But unlike the creeping red goo in the 1958 horror flick, the one he’s talking about is a massive area of warm water sitting off the coast right now. It’s kind of like a bathtub out in the ocean.

"That warmth of the offshore waters has caused a huge change in the distribution of a lot of marine life," Mantua said.

Marine life, like krill and sardines, seeks out cold water. Because of the blob, that cold ocean water is sitting close to shore this year. So, that's where whales come to feed, and that's where the ship strikes happen.

In spite of this trend, scientists aren't concerned by how many whales have died so far this year. With so many whales nearby, residents could just be seeing the ones that would otherwise die far out at sea. As for Bob Hutchinson and the three whales that washed up on his beach in Pacifica: It’s not time to worry, just yet.

But, with lots of whales still migrating north through a crowded ocean of fishing boats and tankers, whether such deaths continue could be up to us.

This story was produced in partnership with the environmental reporting project, iSeeChange. More information can be found at www.iseechange.org.

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