New England should see a "moderate" red tide this spring and summer, according a report released this week by the Woods Hole Oceanographic Institution and the National Oceanic and Atmospheric Administration. Some shellfish harvesting beds might have to be closed in order to prevent people from eating contaminated food and getting sick. Red tide is the common name for a harmful form of microscopic algae that turns the ocean a rust color and accumulates in shellfish, which can be deadly to humans if eaten. Each spring, warming ocean water and sunlight cause the explosive growth in the Gulf of Maine, usually by the end of April.

via Moderate red tide forcast for New England this spring | USA Today.