Off the coast of Florida, scientists and volunteers trained daily still dive to the seabed to plant young corals and monitor their adaptability to the increasingly warming sea level.
This activity belongs to the "Rescue Coral" program of the University of Miami, implemented since 2015 to restore coral reefs, serve research and raise community awareness. Accordingly, scientists focus on finding species that are more resistant to climate change.
Program manager Devon Ledbetter said that some species have high resistance, helping them survive and recover from seawater heat waves. Ms. Ledbetter made this assessment to AFP during a dive at Rainbow Reef, about 4.8 km from Key Biscayne (Florida, USA).
Coral reefs not only maintain a diverse marine ecosystem but also act as natural breakwaters, helping to protect coastlines from erosion and flooding caused by storms. However, this ecosystem is under increasing pressure as ocean temperatures rise.
The record heatwave at sea that began in 2023 has put deer horn corals and deer horn corals - two ecologically important species - in a state of "functional extinction" at the Florida Reef.
According to the US National Oceanic and Atmospheric Administration (NOAA), the fourth global coral bleaching may have ended in mid-2025. However, the strong El Nino is raising concerns that corals will continue to be widely bleached, including the waters off Florida.
During the restoration process, scientists have applied many farming methods and brought coral back to the natural environment. Some fast-growing species are farmed on television antenna-like floating structures; others are fixed on seabed frames or attached to substrates before being brought down to the reef. Shields are used to limit coral-eating fish.
To monitor, the research team placed a reference color palette next to newly planted clusters, thereby recognizing color changes and detecting early the impact of high temperatures.
Corals live symbiotically with microorganisms in tissues. When temperatures or levels of pollution increase, algae can leave tissues, causing corals to lose color, become susceptible to disease and die.
Ms. Ledbetter said that through observation, mountain star corals tend to be better resistant to bleaching and heat shock. This summer, the program planted 615 individuals, of which 228 individuals were put into heat resistance research. The results have been provided to the state's environmental and wildlife management agencies.
