Healthy ecosystems are invaluable to the businesses and economy of South Florida and the Florida Keys. Florida’s Coral Reef is the only bank barrier coral reef in the continental United States. It provides significant support to the foundation of the bustling Florida Keys marine economy, and attracts more than 5 million visitors each year. These visitors support 4.7 billion in spending and income generated annually in the Keys. Losing Florida Keys reefs would result in cascading effects to the region’s economy and culture that are firmly rooted in the health of the local marine ecosystem. 

Each component of the mission provides critical support to reaching the goal of improving the ecosystem function of the seven iconic Keys reefs. This will allow the reef systems can continue into the future, providing habitat for countless marine organisms, coastline protection, and supporting ample tourism opportunities. 

During active restoration work, there may be temporary access changes such as the temporary removal of mooring buoys. This would allow for the work to be completed efficiently and safely. Mooring buoys would be returned when stewardship and maintenance activities start at the sites following active restoration work. Ample public notice is given if/when restrictions are needed.Community divers will be able to access our outplant and nursery sites through the Iconic Reef Guardians program, which will mobilize volunteers to help with coral husbandry.

It was the region’s longest-lasting marine heatwave in three decades. Higher-than-average warm water temperatures started in February 2023. The first Bleaching Watch was issued on May 21, 2023.

NOAA experimental models forecasted a 70-80% chance that extreme ocean temperatures would persist until October 2023. In October, cool fronts moved in and sea temperatures dropped. The season’s final alert for the region was issued on October 22, 2023.

73.4˚F – 84.2˚F (23°C< – 29°C)  is the optimal temperature range for reef-building corals in this region. A 2°F (or 1°C) rise in temperature can CAUSE A CORAL TO BLEACH, meaning the coral expels its SYMBIOTIC ALGAE, which provides the coral with its color and nutrients. It can take several weeks of stress before corals pale and/or turn white.

Bleached corals appear stark white but can recover or adjust to the changing conditions by modifying their symbiotic algal partnerships, something some experts consider may be key to their evolutionary success over millions of years.

Bleaching occurs in response to multiple stressors acting alone or in concert, including low salinity, sedimentation, disease, and temperature extremes. Most bleaching is associated with abnormally high seawater temperatures, which have occurred with increasing frequency.

Coral bleaching does not always lead to death. The elevated temperatures as well as the duration of the elevated temperatures are critical factors in the difference between coral bleaching and coral mortality.

When the ocean temperature is above the 90th percentile for a specific length of time — meaning that the temperatures are warmer than 90% of the previous observations for a given time of year — you’ve got a marine heat wave.

Heatwaves can last for weeks, months, or years and are monitored by NOAA’S PHYSICAL SCIENCES LABORATORY and NOAA CORAL REEF WATCH.

Mild bleaching in Florida Keys National Marine Sanctuary has occurred annually since 2011 typically at its extreme in early to mid-August. The last severe bleaching event was 2014-2015.

At the onset of bleaching, Mission: Iconic Reefs partners incorporated bleaching threshold data into their adaptive management plans, voluntarily scaling back their coral outplant efforts and focusing on nursery and outplant site coral care to reduce stressors—cleaning nursery and structures, culling diseased pieces of coral, and general maintenance to improve conditions. 

On July 21, 2023, Florida Fish and Wildlife Conservation Commission and Florida Keys National Marine Sanctuary released “Interim Protocols for Management of In-Water Nurseries, Coral Transport and Coral Outplanting” for the summer and fall of 2023. These protocols establish temperature and disease thresholds in nurseries and at outplant sites plus transport limitations. 

Elevated temperature duration leading to widespread bleaching and mortality prompted the emergency removal and massive collaboration in order to safeguard the genetic diversity of Florida’s coral reef-building species. Mission: Iconic Reefs managers and partners Coral Restoration Foundation, Mote Marine and Laboratory, and Reef Renewal along with many volunteers and partnering organizations quickly evacuated portions of their in-water nursery stock to their land-based facilities. 

Twelve thousand coral specimens were moved to land-based facilities during the marine heatwave as refuge from HOTTEST OCEAN TEMPERATURES ON RECORD. These locations included Mote’s facilities in Sarasota, Summerland, Islamorada, and Key Largo, Keys Marine Laboratory, SeaBase, The Reef Institute, Aquarium Encounters, Dynasty, and the Plant a Million Corals facility. 

The Herculean, multi-agency effort helped ensure maintenance of genetic diversity by moving some corals to gene banks.

In response to extreme ocean temperatures, NOAA used its emergency authority to create a temporary special use area in Florida Keys National Marine Sanctuary to protect endangered corals that were RELOCATED TO A NURSERY in federal waters approximately five miles southeast of Tavernier, Florida. The temporary regulation lasted 60 days, and exercised an option for one 60-day extension, prohibiting all entry except for continuous transit without interruption.

The Tavernier (Temporary) Special Use Area, protecting 2,800 coral fragments in 70 feet of water, limited physical impact to sensitive coral nursery stock from anchoring, unintentional fouling of fishing gear, and bottom tending fishing gear including traps.

It had been 20 years since the sanctuary utilized the emergency provision. In 2003, a similar coral stress event resulted in the White Bank Dry Rocks (Temporary) No-Entry Zone near Key Largo. GPS location of any managed area can be found in the free, MARINE SANCTUARY EXPLORER mobile app by searching Special Use Area.

In mid-July 2023, NOAA and Mission: Iconic Reefs partners— Mote Marine Laboratory, Nova Southeastern University, Coral Restoration Foundation, Keys Marine Laboratory, Reef Renewal USA, The Florida Aquarium, The Reef Institute, and University of Miami— worked to preserve the last remaining live elkhorn and staghorn corals from Florida’s Coral Reef.

NOAA organized the banking two fragments from each unique genetic individual of staghorn (Acropora cervicornis) and elkhorn (Acropora palmata) corals, which are listed as threatened under the Endangered Species Act. One fragment was placed at Mote Marine Laboratory in Sarasota and the other at the Reef Institute in West Palm Beach.

Ongoing fate tracking efforts by Mission: Iconic Reefs Monitoring Team and M:IR partners identify survivors and assess overall mortality to further understand exactly how corals respond to elevated temperatures. The information can be used in coral restoration by incorporating surviving heat-tolerant corals genets.

In mid-August, NOAA conducted a ten-day assessment in the Florida Keys National Marine Sanctuary (FKNMS) to document the condition of staghorn and elkhorn corals outplanted by restoration partners Mote Marine Laboratory, Reef Renewal, and Coral Restoration Foundation.

Fully bleached and recently dead corals were observed in every location. Approximately 30% of outplanted staghorn and 45% elkhorn coral died– likely due to the heat stress. Approximately 90% of elkhorn and staghorn coral exhibited heat stress. Partially bleached pockets of corals were observed at most sites. Some completely unbleached corals were observed. Anecdotally, boulder corals showed much less bleaching and minimal mortality as compared to the branching elkhorn and staghorn corals.

A follow-up assessment of the sites took place in February 2024.

We all rely on healthy marine ecosystems to support life on this planet. NATIONAL MARINE SANCTUARIES and MARINE PROTECTED AREAS  are a nature-based solution in the fight against climate change. They help build climate resilience and store carbon while conserving biodiversity by protecting depleted, threatened, rare, and endangered species and populations.

Through its RESTORATION BLUEPRINT and MISSION: ICONIC REEFS coral restoration initiative, Florida Keys National Marine Sanctuary is actively safeguarding essential ecosystems responsible for local and global contributions to biodiversity, carbon storage, livelihoods, coastal security, and cultural heritage.