Understand what red tide is. A red tide is a high concentration of certain species of microscopic algae that gather in patches of ocean water, tinting it red. The algae produce a toxin that paralyzes and suffocates fish and poses possible dangers to humans.
Learn where and when red tides occur. Red tides usually affect both sides of the Atlantic, the Pacific coast north to Alaska and the Gulf Coast. Weather conditions, rather than seasons, predict when a red tide is likely. Some scientists speculate that red tides happen due to high temperatures and lack of wind and rainfall, which causes high levels of salinity and nutrients in the water and an increase in algae populations.
Check for updates on your area's red tide status. Many areas post links on state-sponsored websites that provide current beach maps and regular, detailed updates concerning signs of possible red tide such as dead fish tallies and algae population levels.
Remember what to do at the beach. Since red tides are transient and in such isolated patches, they do not always affect an entire beach. Even if your part of the beach has been affected by red tide, if the waters are calm, you may experience no problems. But rough surf can make the algae airborne in the salt spray, which can cause skin, eye and throat irritation for swimmers. If you experience these symptoms, leave the water and wash yourself thoroughly.
Eat only seafood that is safe to consume in a red tide-affected area, if you choose to eat seafood. Fish, crabs, shrimp and lobster are safe bets because the algae organism's toxin does not penetrate their fleshy tissues.
Avoid certain kinds of seafood. Do not eat sick or dead fish of any kind. Avoid eating oysters, clams, mussels, whelks, scallops, quahogs or other bivalves or shellfish, because they are susceptible to the algae organism's toxin accumulating in their soft tissues. Toxins can reside in shellfish for weeks or months after a red tide has dissipated, so never assume seafood in a recently red tide-affected area is safe to eat.
Recognize the symptoms of neurotoxic shellfish poisoning or paralytic shellfish poisoning -- two common results of consuming toxic seafood from red tide waters. These illnesses attack the human nervous system within 30 minutes of exposure and may cause numb lips, tingling sensations, uncoordinated movements, incoherent speech, dizziness, headache, diarrhea, vomiting, nausea and -- rarely -- death. If you notice these symptoms in yourself or someone else, get emergency medical help immediately. If you can, induce vomiting to help relieve gastrointestinal and respiratory discomfort. Symptoms usually last 12 to 24 hours.
