Ramping up the fight against Florida’s red tides

Abstract

The words “red tide” routinely generate red alerts among Florida’s fishermen, coastal property owners, tourism operators, and health officials. This past summer and fall were no exception. These toxic algal blooms—which often tinge the water red but sometimes turn it brown, orange, or even slightly greenish—close beaches, kill innumerable fish, and taint filter-feeding shellfish such as oysters, rendering them inedible. The neurotoxins generated by the phytoplankton that create red tides also affect birds, marine mammals, and sea turtles and can harm human health. Breaking surf lofts toxin-filled droplets of sea spray that can irritate lungs and severely aggravate lung conditions, such as emphysema or asthma. Adding to their devastation, red tides can seem random. Some years, as in 2017 and 2018, they persist for months; in others, they may hardly make a showing or bloom and then fade only to return with a vengeance. Toxic algal blooms known as red tide, which often tinge the water red but sometimes turn it brown, orange, or even slightly greenish, close beaches, kill fish, and taint shellfish. The bloom pictured took place in September of 2016 in the Gulf of Mexico in the coastal waters of southwestern Florida. Image credit: Mote Marine Laboratory & Aquarium. Scientists now have a decent sense of when and where red tides will appear, but new data-gathering efforts could help monitor the blooms as they develop, providing more accurate red tide forecasts for coastal areas. And researchers are starting to devise and test ways to mitigate or control Florida’s red tides to improve the quality of life in the state's coastal communities. But the age-old phenomenon of red tides continues to present scientists and policymakers with complex research and management challenges. Although the most distressing effects of red tides manifest themselves in coastal waters, these harmful algal blooms …