Red tide algae’s deadly trail of marine animals triggered state of emergency in Florida
FLORIDA’S governor has made official what residents of southwest Florida already knew: The bloom of toxic algae that has darkened gulf waters is an emergency. The red tide has made breathing difficult for locals, scared away tourists, and strewn popular beaches with the stinking carcasses of fish, eels, porpoises, turtles, manatees and one 26-foot whale shark.
The governor is facing Sen Bill Nelson, this autumn at the ballot box in a contest for the Senate seat Nelson has held for three terms. Each has accused the other of not tackling the red-tide calamity and the simultaneous bloom of a different type of algae that is clogging rivers and canals and putting a scum on top of Lake Okeechobee.
Residents in crowded retirement communities are reporting respiratory distress from the vapours of the microscopic red-tide organism called Karenia brevis. A recent study found a 50 per cent spike in hospital visits resulting from respiratory problems during red-tide blooms.
The red tide has been gradually moving north, to the mouth of Tampa Bay, according to state data tracking the red tide. For many places, the daily reports continue to say “Water Color: Dark” and “Respiratory Irritation: Intense.” Worst of all are the reports that state “Dead Fish: Heavy.”
Rick Bartleson, a research scientist with the SanibelCaptiva Conservation Foundation, said water samples offshore show lethally high concentrations of algae.
“There’s no fish left. Red tide killed them all,” he said. “All of our concentrations of red tide are still high and would still kill fish if they were out there.”
The algae is found in marine environments for most of the year, but the past two months have produced high concentrations, said Kelly Richmond, a spokeswoman for the Florida Fish and Wildlife Conservation Commission. The duration of blooms can be affected by sunlight, nutrient and salinity content, she said.
The toxins can aerosolise in the wind that drifts ashore, triggering respiratory problems or worsening conditions such as asthma. That has incited many tourists and some locals to flee.
Adrienne Miceli-Trask, 52, a salon owner who helped organise the Hands Along the Water protest in Sarasota, said: “It’s not just on the beach. It’s in our intracoastal waterway. It’s in the air. It’s toxic. Somebody’s backyard on the intracoastal is totally filled with dead fish. It’s disgusting.”
Scientists are trying to figure out why, exactly, the current red tide along the Gulf Coast has been so protracted and deadly. State officials and scientists point out that, at base, this is a natural phenomenon. Fish die- offs were noted by Spanish explorers in the 1500s and have been well documented since the 1840s.
But the incidences of red tides seem to have increased since the 1950s and 1960s. Climate change could be a factor - warmer waters, up to a certain point, are congenial to algal growth. The Gulf of Mexico’s surface temperature has warmed by about two degrees Fahrenheit since 1977.
There is a more direct human handprint on the current crisis: Florida’s landscape and the flow of water have been radically altered by agriculture, canals, ditches, dikes, levees and the sprawling housing developments that have sprouted as the state’s population has boomed.
In the old days, Bartleson said, rainwater slowly filtered into the aquifer or seeped into estuaries. Now it rushes rapidly, unfiltered, into rivers and bays and into the gulf, typically loaded with agricultural nutrients such as nitrogen and phosphorous, which feed the algae.
Hurricane Irma struck the state head- on last September, and the red-tide bloom began about a month later. The US Army Corps of Engineers was forced to release massive amounts of nutrient-laden water from Lake Okeechobee to prevent the overtopping of the venerable Hoover Dike.
Those nutrients fuelled green algae in the inland canals and rivers and flowed through the Caloosahatchee River into the shallow waters along the Gulf Coast. It is plausible that fuelled the red-tide bloom.
Historically, algal blooms become more prevalent in autumn and decline in late winter and spring. Less rainfall and increased wind could potentially ease this deadly red tide. For now, there’s no end in sight. — WP-Bloomberg