News Release

Coral Bleaching at Biscayne National Park

Pete Wintersteen

News Release Date: August 3, 2023

Contact: Ted Firkins, 786-335-3630

HOMESTEAD, Fla. – Biscayne National Park staff are monitoring elevated water temperatures and resulting impacts on the park’s coral reefs. Higher than average water temperatures, occurring earlier in the season than usual, have led to extremely warm conditions and coral bleaching.

 When water temperatures increase beyond the normal range, stressed corals may expel the colorful algae, called zooxanthellae, that live within the coral’s clear tissues. The coral will then appear 'bleached,' as its white skeleton is then visible. Because zooxanthellae provide most of the coral polyp's food, prolonged bleaching can cause the polyp to starve. Bleaching weakens corals and makes them more susceptible to disease and injury. If stressors like extremely warm water subside in a timely fashion, corals can take in new zooxanthellae and survive bleaching events.  

Park staff, in cooperation with academic, federal, state and local agencies, are currently working to monitor, document and respond to this coral bleaching event.  Coral conservation efforts at the park include rearing larvae in nurseries, replanting coral, removing marine debris, installing mooring buoys and inventorying and monitoring populations and their responses to stressors. An ongoing research project to inform management efforts to conserve coral includes identifying corals that are better able to withstand increased temperatures. The park is also working to increase visitor understanding and promote resource stewardship through educational programs and enforcement of regulations. 

“Coral reefs are among the crown jewels of Biscayne National Park,” said Biscayne National Park Superintendent Penelope Del Bene. “Not only are they a major reason visitors come to the park, but they are also critical for supporting healthy marine life in general. We will continue working with our partners to monitor and respond to this event.” 

Losing coral reefs impacts the incredible diversity of fish and other organisms that live in the park, commercial and recreational fishing and the tourism industry. Reefs also provide shoreline protection for coastal communities by absorbing wave energy and reducing flood risk. Reef decline reduces this protective barrier.  

What you can do to help:  

• Use park mooring buoys instead of anchoring near coral reef patches.  
• Wear sun protective clothing and reef safe sunscreen.  

• Keep your distance from corals while snorkeling or SCUBA diving.