Florida Bay: Devastation Goes Unrecognized by Most South Floridians

Florida Bay: Devastation Goes Unrecognized by Most South Floridians

Categories: Blog, Special Report: Florida Bay

Did you know that nearly 10 percent (or about 80 square miles) of Florida Bay, between the Florida Keys and mainland Florida, has been ravaged by a wildfire that began in the summer of 2015 and continues to burn more than one year later? Of course you didn’t know about this, because there was no fire in Florida Bay.  Rather, Florida Bay was subjected to a massive die-off of seagrass that has swept across the center of the bay, not unlike a wildfire.

Wildfires are attention-grabbing, as people can relate to the impacts they wreak on human and natural environments. Whole forests are consumed over a matter of a few days.  Houses and livelihoods are lost, while brave firefighters attempt to quell the impacts of these disasters.  The general public is also receptive to the causes of wildfire.  With the ever-increasing drought in the western United States, people understand the linkage between the lack of water and the increased risk of wildfire.  They also understand that many wildfires are preventable.

The 1969 Cuyahoga River fire notwithstanding, water bodies are not known as being readily combustible ecosystems. Nonetheless, a disaster the equivalent of a wildfire has decimated a 50,000-acre swath of Florida Bay that holds international distinction as protected wilderness, a United Nations World Heritage Site, an International Biosphere Reserve, a Wetland of International Importance and one of the best damn fishing spots in the world.  Sadly, this seagrass die-off was a man-made disaster that could have been prevented.

As with forest fires, the cause of the Florida Bay disaster was a lack of water—a lack of freshwater to be exact. Florida Bay receives freshwater from the Everglades.  This “River of Grass” once flowed continuously from Lake Okeechobee all the way to the Florida Keys, providing a constant stream of freshwater throughout the year.  Because Lake Okeechobee was cut off from the Everglades, the Everglades no longer receives a base of inflow from the north, and Florida Bay is now more dependent than ever on rainfall to maintain healthy salinity levels.  Due to a local drought in the summer of 2015, Florida Bay salinity sky rocketed, thus lighting the match that started the blaze.

Initially, the fire spread rapidly, as seagrass die-off fueled more seagrass die-off.  Plants compromised by high salinity and the high summertime temperatures were no longer able to produce enough oxygen to sustain life in the harsh anoxic conditions of the bay’s mud.  With an influx of dead grass, more oxygen was needed by decomposing bacteria than could be supplied by the surrounding live grass.  This led to a rapidly expanding die-off area through the summer and into the fall.  As we moved into the winter, cooler temperatures and higher rainfall helped to slow the expansion of the fire, but it did not make the problem go away.  Today, at the outermost reaches of the die-off zone, there is a patchy mix of live and dead grass.

Like a charred forest, the seagrass will take years, possibly decades, to recover. Why?  First, the mud within the die-off area is still “smoldering.”  Dead remains of seagrass buried in the mud is still decomposing, consuming all oxygen and creating harsh conditions for new growth.  Next, seagrass typically grows vegetativley by sprouting new leaves along the length of runners that spread laterally through the mud (If you have St. Augustine grass in your yard, you understand quite well this pattern of growth).  Finally, seagrass requires a lot of light reaching the bottom in order to grow.  However, the bay is now subject to more frequent bouts of murky water caused by winds that re-suspend mud from the shallow bay bottom, thus blocking any sunlight from getting to the seagrass.  Over time, new shoots of seagrass will emerge, paving the way for more grass to become established.  Fish and shellfish populations will gradually recover as well, but over much longer timeframes.

Despite what some agencies will say, the Florida Bay wildfire was preventable.  Following a similar disaster that began in 1987, the Comprehensive Everglades Restoration Plan (CERP) was developed to restore the natural flow from Lake Okeechobee back to the “River of Grass” and Florida Bay.  This plan, which included 68 project components, was authorized in 2000.  However, nearly 16 years since the passage of CERP, there have been no projects completed.  We have made significant progress over the past 7 years, but there have been no CERP projects authorized to address this issue of flowing water from Lake Okeechobee to the south.

Few have observed the decimated area Florida Bay disaster firsthand. It is a remote part of the bay once frequented by scores of backcountry fishing guides and their clients.  Several guides have said that the grass flats just south of Rankin Bight were among the best fishing spots in South Florida.  To visit there today, one would observe only murky water, occasional clumps of algae, mounds of dead and decomposing grass on the windward side of nearby mangrove islands, such as Dump and Buoy Keys, an overabundance of Cassiopea (also known as upside-down jellyfish), and zero fishing boats.

We cannot erase the damage from the most recent Florida Bay wildfire.  Nature will have to heal itself once again.  However, we should certainly do what we can to prevent this disaster from ever happening again.  This means prioritizing planning, authorization, and construction of CERP projects that we know will bring substantial benefits to Florida Bay, including the Central Everglades Planning Project and the EAA Reservoir.