A combination of extreme heat and days of rain may have led to a fish kill in Biscayne Bay.
Evidence showed the cause was a combination of extreme heat and numerous days of rain, which reduces oxygen levels in waterways, officials said.
"This incident is another reminder that the health of our beloved Bay is in jeopardy, which is why Miami-Dade County is committed to taking all possible action to turn around the crisis facing our waters," Miami-Dade County Mayor Daniella Levine Cava said in a statement. "We are working to aggressively accelerate investments in replacing or repairing critical water infrastructure and septic to sewer conversion."
Earlier this year, the county began implementing a ban on fertilizer use during the rainy season, when nutrients are more likely to be carried in water flowing off the urban landscape.
“We are committed to taking swift action to protect the ecological gem that is Biscayne Bay,” said Miami-Dade County Mayor Carlos A. Gimenez. “This time of year the marine life in our bay is susceptible to high heat levels, and we want to make sure we understand the causes of this most recent incident so that we can as quickly as possible restore conditions so that our marine life can continue to thrive.”
DERM staff collected and evaluating water quality data from the bay and canals to better understand the cause of and conditions that contributed to the fish kill that occurred primarily in the Julia Tuttle basin, which lies between the Julia Tuttle Causeway and the JFK Causeway.
The basin is already in a distressed state due to seagrass die-off, where DERM found that over 75% of the seagrass has been lost. This is likely a contributing factor to the fish kill, along with high water temperatures and low dissolved oxygen levels, as seagrasses are key to helping oxygenate the water.
Two Miami-Dade Fire Rescue boats from PortMiami deployed to select spots within the Julia Tuttle basin in an attempt to aerate the water to provide more oxygen, and the Parks, Recreation and Open Spaces Department helped secure the dumpster at the marina.