Sea lions in California are under duress from a rather unassuming source: algae. Driven by higher water temperatures and pollution, toxic algae is leading to fatal brain damage in many California sea lions.
Domoic acid poisoning is emerging as a key threat this year to sea lions and other animals that ingest the toxin while eating fish and other sea creatures that feed on algae. Authorities say the algae may have impacted some birds and dolphins as well, and warn that it could be harmful to humans who eat shellfish.
According to researchers, the neurotoxin that the Pseudo-nitzschia algae produces ravages the brains of sea lions until they no longer know basic survival functions, like how to evade predators and find food. It has also caused sea lions to have seizures and paralysis.
Scientists say this is the “worst year ever” for cases of domoic acid poisoning. Dozens of disoriented sea lions were picked up by Marine Animal Rescue last month. Rescue workers try to save the animals by flushing the toxin out of the animals’ systems, but for many it’s too little too late. In Laguna Beach alone, at least 14 sea lions died in April from domoic acid poisoning.
While no human cases have yet been reported this year, officials warn against eating mussels, clams, or whole scallops harvested by sports shellfish collectors in Santa Barbara County. Commercially harvested seafood is tested before it goes to market.
Some have dubbed sea lions the “canaries of the marine environment” because they are indicators of ocean health. It seems they’re trying to tell us something.
Photo, posted March 10, 2013, courtesy of John Menard via Flickr.