Coastal A-Z [return to Table of Contents] Domoic Acid and Sea Lions A naturally-occurring neurotoxin called domoic acid has been responsible for the deaths of hundreds of sea lions in southern California during the last few years. Domoic acid is a chemical that is produced by algae or plankton when it blooms. Domoic acid was not discovered until the late 1980s, and scientists still don't understand why or when the algae blooms occur, nor can they predict which blooms will produce toxins and when they will impact wildlife. What is known is that anchovies, sardines, clams, mussels and other sea life ingest the algae. Then when sea lions (and to a lesser extent, dolphins) eat the anchovies and other affected sea life, they become sick. The toxin affects the part of the brain known as the hippocampus and causes rapid deterioration. Affected sea lions exhibit head weaving, bobbing, bulging from the eyes, mucus from the mouth, disorientation and sometimes seizures. The sick sea lions are almost always female, and are often pregnant. Unfortunately, not much can be done for the affected sea lions. Treatment typically consists of injecting approximately 4 liters of an electrolyte solution containing vitamin B-12 to flush out the toxin. The mammals are also given medication to control seizures. The survival rate is only about 25% to 50%. If you see a sea lion in distress, it's important that you don't go near, touch or feed the animal. You should contact a lifeguard or a marine mammal care center. Four such facilities exist in southern California: Santa Barbara Marine Mammal Center (805) 687-3255 http://www.fsacares.org/wc103lze.htm Fort MacArthur Marine Mammal Center in San Pedro (310) 548-5677 http://www.mar3ine.org/aboutmmcc.htm Pacific Marine Mammal Center in Laguna Beach (949) 494-3050 http://www.pacificmmc.org Sea World in San Diego (800) 541-7325 http://www.adventureisland.com/seaworld/ca/default.aspx Scripps Institute of Oceanography Finds Domoic Acid in San Diego waters http://www.news-medical.net/?id=418