The local sea lion nicknamed Freeway that was repeatedly found far inland may have been showing signs of poisoning by domoic acid, the neurotoxin produced by the algae, an illness shared by hundreds of marine mammals that died or were sickened by a recent bloom off the Southern California coast.
A spokesperson for SeaWorld, Tracy Spahr, confirmed that Freeway may have also been a victim of the algae back in 2021 as well. That timing coincides with when the pinniped began showing signs that, in retrospect, could be interpreted as a symptom of a neurological infection.
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This year, more than a thousand marine mammals along the Southern California coast have become sick or died due to toxic algae, including at least six in San Diego.
SeaWorld veterinarian Kelsey Herrick explained to NBC 7 that the blooms are likely seasonal and often occur during periods of warmer water. The demoic acid doesn’t sicken the fish that ingest it, but it does and can prove deadly to marine mammals further up the food chain.
Freeway, who was spotted far from the ocean three times, was euthanized in April of this year after veterinarians discovered he also had an untreatable protozoal disease.
The sea lion was spotted walking onto Harbor Island Drive in November of 2021. Next, SeaWorld received calls about Freeway from a deli in Mission Beach and near the Navy Base in Point Loma. Staff monitored him until he went back into the ocean a week later.
Several months later, Freeway journeyed away from his habitat and was found on Highway 94 in January 2022. The SeaWorld rescue team received a call about him in Encinitas but he again returned to the ocean on his own.
The third and final time Freeway ventured out, he was found walking in a storm drain under the National City Bridge in April of 2022.