CA HAB Bulletin Special Issue May-July 2023 provides a high-level summary of the Domoic Acid event that occurred in Central and Southern California from May to July 2023. Click here to read more.

• This special bulletin issue describes a major Domoic Acid (DA) event that lasted over a three-month period. At the end of May 2023, the first few strandings of symptomatic California Sea Lions (CSLs) began showing up on beaches, which alerted marine mammal rescue organizations to an impending problem. A week later, it was becoming clear that the dramatic increase in stranded or dead CSLs and long-beaked common dolphins throughout the Santa Barbara Channel region was likely due to DA poisoning. The tell-tale signs of the neurotoxin were prevalent in CSLs and other pinnipeds along popular beaches – lethargy, disorientation, seizures, erratic behavior – as the event expanded to encompass the region from San Luis Obispo (SLO) County in central California to San Diego County in southern California over the next few weeks. In fact, many animals displayed extreme aggression with at least 30 reports of attacks, some serious, on beachgoers in the months of June and July.