With recent beachings of sick and dead marine animals, a warning has been extended to include Los Angeles County in a ban against eating certain seafoods.
By Cortney Litwin/Staff Writer
First it caused disorientation and seizures in marine mammals and birds that has hit near-epidemic proportions on local beaches. Now it’s a threat to seafood lovers.
Domoic acid, a naturally occurring neurological toxin from blooming marine algae, has prompted the state Department of Health Services (DHS) to issue a warning on Friday, urging the public to avoid eating sport-harvested shellfish, sardines and anchovies from Los Angeles, Ventura and Santa Barbara counties. The toxin can cause human illness that mimics flu symptoms, and in more severe cases, memory loss, coma and even death.
This may also be cause for alarm for grunion-runners during fishing season, which begins June 1. The DHS will be conducting tests on local grunion this week to see if the toxin poses a risk, according to Greg Langlois, a marine biologist with the DHS.
Dozens of sea lions on local beaches have become infected with the toxin, “more than 30 just last week,” said Lifeguard Capt. Nick Steers. Dolphins and birds, including the endangered brown pelican, have been infected as well. The California Wildlife Center and the Marine Mammal Care Center have become so overloaded with animals they are performing triage on beached animals.
“Which means they evaluate them first,” said Steers, “and take the most severe cases away,” leaving others on the beach temporarily.
Steers added a warning to stay at least six feet away from poisoned animals, because “they are fish-eaters and have very sharp teeth.”
No one seems to know why this particular algae-a diatom called Pseudo-nitzschia-is blooming so heavily. It’s a different phenomenon than the usual summertime “red tides” that cause restrictions on eating shellfish.
Scientists discovered the diatom in 1987 after a mysterious outbreak of food poisoning occurred in Eastern Canada. Then a large bloom in Central California waters in 1991 caused sickness in hundreds of marine mammals.
Some experts have linked the toxin to nitrogen from sewage treatment plants because diatoms feed on nitrogen. Paul Ahuja, a marine biologist with Heal the Bay, disagrees with that theory, at least regarding the blooms in Los Angeles area waters.
“Outfall from treatment plants doesn’t seem the likely cause,” he said, because the blooms aren’t near where the sewage is dumped.
However, “they’ve [biologists] shown a cause for increased algae blooms off the Gulf of Mexico from effluent from poultry and pig farms,” he said.
Biologists have been keeping a watchful eye on local waters since domoic acid intensified in Central California waters this spring. Shellfish are being continually tested for the toxin, according to DHS. Twenty parts per million (20ppm) of domoic acid is considered toxic.
On May 3, Malibu Beach tested at 28 ppm. And the toxin can appear suddenly. On the same day, domoic acid in Portuguese Bend in Palos Verdes was non-detectable, but by May 10, the waters there tested at 56 ppm. Santa Barbara near the Ventura County line tested at 380 ppm on May 10.
“Things aren’t going away,” said Langlois. “If anything, it indicates it’s increasing as of last week.”
A spokesperson for the DHS said they are monitoring the situation closely to see when the seafood ban can be lifted, but it’s hard to anticipate.
“No one understands the magic combination that creates a bloom,” said Langlois.