State Investigating Seagrass Die-off in Florida Bay

A couple months of drought-like conditions for the southern region of the state coupled with a lack of freshwater being sent down through the Everglades by the South Florida Water Management District are among the factors that have caused an extensive seagrass die-off in the northern region of the Florida Bay, according to experts.

“Everything looks just like the 1987 incident,” said Jim Fourqurean, a Florida International University marine ecologist who specializes in seagrass study. “So I’m not surprised to see it happening again.” As in the late 1980s disaster, which eventually caused a massive algae bloom that devastated marine life and shut down recreational fishing in large portions of the 850-square-mile bay, seagrass die-off was a precursor.

The most recent incident was first noticed by an Everglades National Park biologist in late June in Rankin Bight, just east of Flamingo and the popular fishing grounds around Snake Bight. After assessment the damage seemed to cover almost 6 square miles in that area as well as 7 square miles around Johnson Key, south of Snake Bight. Other surrounding areas, such as Whipray Basin, south of Rankin Bight, showed smaller patches of seagrass loss as well.

Margaret “Penny” Hall, a research scientist with the Florida Fish and Wildlife Conservation Commission who is overseeing a team investigating the die-off, described that entire area of the bay as a yellowish, stinky mess. Hall, whose team regularly monitors conditions there, said they saw no warnings of this happening to the level it has. Backcountry anglers who frequent the bay, though, had been reporting lower fish counts over the past few summer months.

FWC focuses their bay condition monitoring on five major areas: Rankin Bight, Johnson Key, Whipray Basin, Rabbit Key Basin and Twin Key. In May, when Hall and her team checked salinity levels, it was slightly above normal conditions at around 50 parts per thousand. In July though, those numbers shot to the 60 and 70 parts per thousand range and caused extreme hypersaline conditions. “That makes it very stressful for seagrass,” Hall said.

In August, when the team headed an expedition to assess the severity of what had been reported, they found out it was a lot more extensive than what they originally thought. And the two main culprits: less-than-ideal weather conditions and a lack of freshwater promised by a series of lagging Everglades restoration projects. “It has really been exacerbated by water management issues over the decades,” Hall said.

While the conditions have closely mirrored the 1980s die-off, Hall said it’s not as widespread yet and hopes a rainy September helped level out the deteriorating conditions in the bay. But, according to both Hall and Fourqurean, a potential algae bloom is never out of the picture.

“Only time will tell,” Hall said. “We’ll just have to ride it out.”

Source: State investigating seagrass die-off in bay | KeysNews.com