An uptick in the cases of domoic acid poisoning in California sea lions found on the coast of San Luis Obispo County has been reported by The Marine Mammal Center in Marin County, which is treating the affected sea lions.
Since July 1 trained volunteers have rescued more than the usual number of sea lions from the Oceano Dunes Natural Preserve area because the sea lions have exhibited symptoms of poisoning.
Center spokesman Giancarlo Rulli said 68 sea lions have been treated since July 1, compared with 70 in all of 2016.
Domoic acid attacks a sea lion’s brain mainly, causing lethargy, disorientation, seizures and death if the animal does not get treatment.
Domoic acid accumulates in small fish such as sardines and anchovies, which sea lions eat a lot of. Algae produce domoic acid.
Center officials said sea lions are treated for the acid toxicity by having the toxin flushed from their bodies, receiving food free of the acid and receiving medication to control seizures.
Domoic acid accumulates naturally in sea lions over time, but repeated exposure can cause long-lasting and serious effects in the animals.
Domoic acid also can cause a life-threatening condition in humans called amnesiac shellfish poisoning when people eat shellfish that have domoic acid in them.
Sea lions with domoic acid often indicate that a threat to humans is on the horizon because the animals are often the first to be affected during a toxic algal bloom.
Center officials are tasked with notifying public health officials when domoic acid is found in sea lions in order to protect the health of humans.