Fish Kill and Algae Bloom

We are passing a tipping point for the Bay not being able to support any life -- literally overnight, the Bay became a deadzone. On Monday morning, August 10th, Miami Waterkeeper’s samplers and members of the public encountered about a dozen dead fish while conducting our weekly fecal indicator bacteria monitoring at Morningside Park. Miami-Dade County DERM monitoring groups conducted their routine monthly sampling nearby, noted very high water temperature (~90 F), and low dissolved oxygen levels. Many species of fish and marine life have been killed, including pufferfish, toadfish, eels, shrimp, trunkfish, pinfish, lizardfish, hogchoker, hogfish, barracuda, parrotfish, angelfish, blue crab, horseshoe crab, seahorses, octopus, lobster, grunts, mangrove snapper and more. 

(Map of community reports of fish kill impacts, updated in real-time. Red dots are fish kill reports; Green dots are algae bloom reports)

 

(Photo credit: Christopher Boykin)

The kill seems to have had an epicenter near Morningside Park, but dead fish were seen from North Miami to Virginia Key. We notified the proper agencies and sent water samples to FWC to check for harmful algae bloom toxins.

On August 12, 2020, Pelican Harbor Seabird Station reported an aggregation of rays nearshore. Scientists believe that this aggregation may be due to low oxygen levels in the water, making it hard for the rays to breathe. Agencies and Frost Science mobilized a rapid response to avoid a ray die-off in this area. View the video here

On August 15, 2020, Miami Waterkeeper mobilized an emergency aeration effort for Biscayne Bay. In coordination with Miami Dade County and PortMiami, fireboats were sent to oxygen-starved areas of the Bay. Anecdotal evidence seems to suggest that this was an effective temporary measure. Oxygen readings from those areas increased by 30% in the direct vicinity of the fireboats and increased by 15% approximately 100 yards from the boats' aeration areas. In the days that followed, the City of Miami mobilized an emergency aeration response by converting stormwater pumps to help aerate nearshore areas throughout the City, including hot spot locations such as Morningside Park. Anecdotally, these aeration efforts seemed to have been effective as a temporary measure to increase oxygen in these areas. 

(Photo credit: Christy Raynor)

(Photo credit: Cody Eggenberger)

Volunteers and members of our 1,000 Eyes on the Water Rapid Response team quickly rose to scientists' plea for help to remove dead and decaying marine life and organic matter from the water. Decaying marine life produces bacteria which can also consume oxygen from the water column, making even less oxygen available for living marine life. Volunteers removed hundreds of pounds of dead fish from shorelines in dozens of locations in the fish kill impact area. Fertile Earth Worm Farm also mobilized and placed compost bins to collect the dead fish from key locations to assist with removal efforts. 

Conditions appeared to be improving by mid-week. However, by August 20, 2020 residents began to report incidents of strange foam accumulating at the water's surface. This foam was white in nature and also changed color to brown. By August 21, 2020, we began to receive reports of sweeping amounts of foam across Biscayne Bay and by late in the day -- we determined that many areas of the Bay and adjoining canals and waterways were already experiencing algae bloom events. Algae blooms appear to be concentrated in the North Bay area between the Broad Causeway and the 79th Street Causeway. Miami Waterkeeper has been coordinating responses to this algae bloom event with scientists and officials from FIU, UM, NOAA, FDEP, DERM, City of Miami, North Bay Village, Miami Shores, and the City of Miami Beach. 

Clean water is what makes Miami, Miami. A dead Biscayne Bay will also affect tourism, fishing, diving, boating, and real estate. People pay a lot of money for beautiful water views. When you have seagrass dying off, when you have sustained fish kills, these are signals of a perishing body of water. It's widespread across northern Biscayne Bay, which means that we're all impacted by this decline. We're finding that we have more and more cases of the Bay not being able to support life.

Note: We do not recommend swimming or eating fish from areas experiencing an algae bloom or fish kill. 

 

 

 

(Photo credit: Adam Cohen)

 

 

 

 

 

Image Source: Kathryn Mikesell Fish kill near Morningside Park, Miami, FL. 


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Fish Kill
Fish Kill and Algae Bloom
HomeMiami Waterkeeper is a South Florida Environmental Group that advocates for Swimmable, Drinkable, Fishable water for all. Working on sea rise, water pollution, coral reef protection, and water issue education.