Early sign of algae bloom detected in Florida Bay

In late September, state biologists navigated through mats of dead seagrass in Florida Bay. About 13 square miles of seagrass meadows died over the summer with early signs of an algae bloom now appearing near Rankin Lake and Garfield Bight.
In late September, state biologists navigated through mats of dead seagrass in Florida Bay. About 13 square miles of seagrass meadows died over the summer with early signs of an algae bloom now appearing near Rankin Lake and Garfield Bight. Florida Fish and Wildlife Conservation Commission

A slimy toxic algae bloom in Florida Bay that researchers thought was years in the future might be just around the corner.

South Florida Water Management District scientist Fred Sklar told district board members last week that levels of chlorophyll are starting to rise in shallow water where miles of seagrass meadows died over the summer. The last time so much grass died in 1987, it took five years for algae blooms to erupt that would devastate the bay for two decades.

If this bloom worsens, it will have taken just months to appear.

“We’re not sure there is a cure,” Sklar told the board. “Once something like this starts, we don’t know what makes it stop.”

The crisis in Florida Bay also has escalated a prolonged fight over water in South Miami-Dade. Farmers have long complained that groundwater is being kept too high, drowning crops. Scientists and environmentalists argue that the bay, which desperately needs more water to flow in from the Everglades, is being sacrificed to save farms.

“You just can’t let … Florida Bay die,” said Jerry Lorenz, Audubon Florida's state director of research. “It’s far more important to get water into Florida Bay and try to mitigate to farms than the other way around.”

At nearly 1,000 square miles, Florida Bay is one of the planet’s most complicated ecosystems with a patchwork of about 24 different basins separated by mud banks. It is also a vital part of the region’s economy and a $723 million a year fishing industry.

The 1990s algae bloom started with the death of more than 15.5 square miles of seagrass after a prolonged drought. So far, scientists have recorded about 13 square miles of dead seagrass around Johnson Key and in Rankin Lake, a shallow bight tucked into a horseshoe-shaped mud bank now beginning to show signs of an algae bloom.

The die-off also coincided with a cloud of yellow sulfide — something Sklar said scientists have never before documented in the bay — that spread across 25 square miles.

“We’re talking between 50 and 75 square miles of seagrass beds that could potentially die,” he said.

A team of researchers who have been monitoring the bay and are now trying to find a solution say that the brewing crisis is no surprise. Years of flood control have robbed the bay of historic sheet flow that fanned across rocky glades from two sloughs in Everglades National Park. What little trickled out of five creeks into the bay in August dropped to the lowest level recorded since gauges were installed in 1996. Worse, a second year of dry weather spiraled into a severe drought. Salinity in some areas reached more than double the concentration of sea water.

The district tried to manage the situation by moving more water south “making it less likely to go into a cascade,” Sklar said. And recent rain — more than 10 inches fell in September — helped flush salt. But it was too late.

“Once the train leaves the station, we don’t know when it stops,” he said.

As Florida Bay wilted over the summer during a deepening drought, scientists arrived to find miles of dead seagrass smelling like rotten eggs in a cloud of yellow sulfide. They suspect hot, salty water from adjacent mud banks slid into the bay and

Another complication: Pollution from vast sugar fields south of Lake Okeechobee must be cleaned. Billions of dollars in efforts have made the water cleaner — but not enough for the sensitive Everglades. Farmers and state officials increasingly hostile to environmentalists have for years blamed the mandate, part of a federal court ruling, for holding up restoration. District board member Jim Moran called it “the gorilla in the room,” that should be relaxed.

“Too much deference is being given to park staff and the NGOs,” Mike Collins, a fishing guide and former board member, complained during the meeting. “If you don’t have science and you don’t have engineering, go sit in the corner and shut up. We don’t have the ability to allow political science to drive this issue any more.”

Environmentalists shot back that Everglades restoration was largely due to their efforts.

“I didn’t realize we built the Tamiami Trial,” which blocked water, said Drew Martin, a conservation chair for the Sierra Club. “We didn’t blow up the Miami falls. We didn’t drain the [Everglades Agriculture Area]. All these things were changes done not by the NGOs but by the development of Florida.”

Jenny Staletovich: 305-376-2109, @jenstaletovich

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