Tiny ocean life creates deadly red tides

Microscopic dinoflagellates, single-celled marine organisms, are the main cause of harmful algal blooms, often called red tides. These tiny plankton multiply rapidly in nutrient-rich waters, turning the sea a reddish color. Some species, like Karenia brevis, produce potent neurotoxins that accumulate in the food chain, leading to massive fish die-offs and economic losses for coastal communities. For example, Florida's red tides have caused significant damage to fisheries and tourism since the 1800s. While some dinoflagellates are harmful, others create stunning bioluminescent displays, highlighting their complex role in ocean ecosystems.