Monitoring the Health of Flower Garden Banks National Marine Sanctuary

NOAA’s National Coral Reef Monitoring Program completes its 2026 survey of the sanctuary

Flower Garden Banks National Marine Sanctuary is one of 10 priority areas monitored through NOAA’s National Coral Reef Monitoring Program (NCRMP), an ongoing effort to understand the health and changing condition of coral reef ecosystems.

The 2026 NCRMP mission at East and West Flower Garden Banks is now complete, marking another round in the sanctuary’s biennial coral reef monitoring record.

During the mission, five dive teams and 26 divers from NOAA and partner organizations surveyed coral reef and fish communities throughout the sanctuary. Researchers documented three key areas:

• Coral demography -  including coral species, abundance, size, condition, mortality, bleaching, and disease

• Benthic cover - documenting what is found on the seafloor, including coral, algae, and bare sand

• Fish assemblages - recording fish species, abundance, and the size of individual fish

  
  

Together, these observations provide a snapshot of the sanctuary's reef communities and contribute to a much larger record of change over time.

Credit: Karl Teague, National Park Service

Building a Long-Term Picture of the Reef

The monitoring program returns to East and West Flower Garden Banks every two years, allowing researchers to compare observations from one survey to the next. Over time, these repeated surveys help scientists identify patterns and trends in the condition of coral, fish communities, and the broader reef ecosystem.

The resulting data are made publicly available through NOAA’s National Centers for Environmental Information and are used in technical reports and the National Coral Reef Monitoring Program Data Visualization Tool.

This long-term monitoring is especially important at Flower Garden Banks National Marine Sanctuary, where the sanctuary's remote, deep-water reefs provide a unique opportunity to study coral reef ecosystems in the Gulf of Mexico.

A Spectacular Annual Event: Coral Spawning

While researchers are monitoring the reef's health over time, Flower Garden Banks National Marine Sanctuary also provides an extraordinary opportunity to observe one of nature's most remarkable events: coral spawning.

Each year, approximately seven to 10 days after the first full moon in August, the reef-building corals of East and West Flower Garden Banks release their reproductive cells into the water in a spectacular synchronized spawning event.

The sanctuary is known for having one of the most abundant coral spawning displays in the Caribbean, in part because of the high density of broadcast-spawning coral species found there.

Coral spawning is an important part of the reef's natural life cycle, helping produce the next generation of corals and contributing to the continued health and resilience of the ecosystem.

Credit: Sarah Rojano, Research Planning, Inc. on contract with NOAA’s National Centers for Coastal Ocean Science.

Why This Research Matters

From routine monitoring to observing annual coral spawning, research at Flower Garden Banks National Marine Sanctuary helps us understand what is happening beneath the surface—and how this remarkable ecosystem is changing over time.

Every survey adds another piece to the long-term scientific record of the sanctuary, helping researchers, managers, and conservation partners make informed decisions about protecting these reefs for the future.

Learn more about NOAA's National Coral Reef Monitoring Program and explore data from Flower Garden Banks National Marine Sanctuary through NOAA's National Coral Reef Monitoring Program Data Visualization Tool.

Source: NOAA National Centers for Coastal Ocean Science / Flower Garden Banks National Marine Sanctuary