Unprecedented toxic algae bloom now in Central Coast waters

[USA] Morro Bay – A massive algae bloom is here: NOAA scientists confirmed Wednesday they found the tail end of a bloom they’ve been tracking for months in the Santa Barbara Channel.

The alga is called Pseudo-nitzschia, and it’s less than five miles offshore, according to NOAA Fisheries Michael Milstein. The organism isn’t visible to the naked eye, but produces a neurotoxin called Domoic acid. The algae is forming a toxic chain that spans the Santa Barbara Channel to Alaska – the biggest marine scientists have seen since 1998.

The bloom produces a neurotoxin that can cause serious damage to people and especially wildlife if it works its way into the food chain.

“We’re on heightened alert right now. We know it’s out there,” Morro Bay oyster farmer George Trevelyan said. The owner of the Grassy Bar Oyster Company, Trevelyan says he does Domoic acid testing weekly, but has tested twice weekly since he heard fisheries were closing in Monterey, Santa Cruz, Oregon and Washington State.

If scientists find elevated levels of domoic acid on the Central Coast, “we would close down and not sell anything, so that could put us out of business for some time,” Trevelyan said.

Scientists are also testing for the toxin at NOAA’s Northwest Fisheries Science Center in Seattle.

“We’re seeing effects on the marine ecosystem we haven’t seen before,” said Vera Trainer, manager of the Marine Biotoxin Program.

NOAA scientists say warmer waters caused by an El Nino could be to blame. The effects are also being seen in marine mammals.

This week, teams with the Marine Mammal Center in Morro Bay rescued three sea lions having seizures, a symptom of Domoic acid poisoning.

“Trembling all over – sometimes we have animals with their heads back and forth,” Marine Mammal Center’s Aubry St. Marie said. “Just unusual movements.”

In the state, the Marine Mammal Center has rescued 94 sea lions with Domoic acid toxicity since the beginning of the year, according to Dr. Shawn Johnson. The sea lions likely ate sardines or anchovies that feasted on the toxic algae.

“It can affect humans, so sea lions are really good sentinels for changes in the ocean,” St. Marie said.

Domoic acid does not taint all seafood, but can impact filter-fish such as oysters, clams, mussels and scallops, as well as crabs and the aforementioned sardines and anchovies. Cooking or freezing does not reduce toxicity levels, according to the CA Dept. of Fish and Wildlife.

Oyster farmers in Morro Bay say they’ve never had dangerous levels there because they’re protected in the Back Bay and not growing seafood in the open ocean. Regardless, they’re playing it safe and testing twice as much as before.

If people eat about a quarter-pound of shellfish with high of the toxin, they may feel like they have food poisoning. If the levels are dangerous, the toxin can cause issues with memory. There have not been any human deaths from the toxin since 1991 because of rigorous testing.

The CA Dept. of Fish and Wildlife says there are no plans to close fisheries south of Monterey County at this time.




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