As temperatures heat up, so do the chances of dead fish floating to the surface of South Florida’s waterways.
Fish kills — which can range from a few dozen fish in a small area to massive stinking numbers across large bodies of water — are most likely to happen during the summer when there’s more rain, runoff and sewage leaks, said Rachel Silverstein, the chief executive officer of Miami Waterkeeper.
Miami Waterkeeper, a non-profit organization, tracks potential fish kill conditions in Biscayne Bay by monitoring weekly for bacteria and dissolved oxygen levels that are indicators of looming trouble. They also encourage reports from boaters and residents who come across fish kills.
Silverstein said fish kills are most common “around canals, nearshore areas, and poorly circulated parts of Biscayne Bay—especially those impacted by stormwater runoff or nearby septic systems.”
What do you do if you see a fish kill?
The first thing you should do if you see a fish kill is take a video and note the exact location and time, said Maria (MJ) Algarra, a spearfisher and founder of the organization Clean This Beach Up.
“If you see dead or dying fish, gasping for air or large amounts of birds diving in the water, anything unusual – try to get a photo,” Algarra said.
Email the information as soon as you can to the Miami-Dade County regulators at baywatch@miamidade.gov or fill out forms in the county’s environmental complaints system. Miami Waterkeeper also has a form on its website, and its team will direct the reports to the right agencies in the county.
How does climate change contribute to fish kill?
As the climate warms, Miami-Dade has continuously broken summer heat records. That trend also increases evaporation, fueling more rain that washes pollution like chemicals, dog poop and trash into canals and Biscayne Bay.
“Warmer water holds less dissolved oxygen,” Silverstein wrote. “But the primary drivers of low-oxygen events in Biscayne Bay are nutrient pollution, algal blooms and groundwater discharges—all of which are intensified during the summer rainy season.”
Leaky septic tanks and aging sewer pipes also contribute to the stew of summertime pollution. It can spur algae blooms and bacteria growth, which sucks up oxygen and can suffocate fish.
This story was originally published by the Miami Herald and shared in partnership with the Florida Climate Reporting Network, a multi-newsroom initiative founded by the Miami Herald, the Sun-Sentinel, The Palm Beach Post, the Orlando Sentinel, WLRN Public Media and the Tampa Bay Times.
