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Exploring Flower Garden Banks National Marine Sanctuary

This year, Scuba Diver Life is partnering with the National Oceanic and Atmospheric Administration (NOAA) to bring you images and stories from each of the United States’ 11 dive-able marine sanctuaries. This month, we bring you to Flower Garden Banks National Marine Sanctuary.

For more than 40 years, national marine sanctuaries have worked to protect special places in America’s oceans and Great Lakes waters, from the Hawaiian Islands to the Florida Keys, from Lake Huron to American Samoa. Backed by one of the nation’s strongest pieces of ocean-conservation legislation, the National Marine Sanctuaries Act, the sanctuaries seek to preserve the extraordinary beauty, biodiversity, historical connections and economic productivity of our most precious underwater treasures. And — lucky for you — most of these places are accessible to recreational divers. Sanctuary waters are filled with unique ecosystems. They harbor a spectacular array of plants, animals and historical artifacts, all waiting to be explored. National marine sanctuaries belong to everyone, so dive in.

Cover image credit: G.P. Schmahl/NOAA

Flower Garden Banks National Marine Sanctuary

Within the vast expanse of open ocean known as the Gulf of Mexico, three vibrant coral reefs and sponge gardens burst with life. Venture 70 to 115 miles from the coasts of Texas and Louisiana and you’ll discover an exciting assortment of marine life. Gigantic whale sharks cruise overhead, and tiny brittle stars nestle into a coral reef that is thousands of years old.

Flower Garden Banks National Marine Sanctuary protects these northernmost coral reefs in the continental United States. It comprises three distinct reef systems: East and West Flower Garden Banks and Stetson Bank. These reefs rest atop ancient salt domes. Here, you’ll find more than 23 different species of coral serving as the foundation of complex yet balanced ecosystems.

Each year, one of the most spectacular ocean events occurs within sanctuary boundaries. Seven to 10 days after the August full moon, these reef-building corals put on a fantastic spawning display when the reef explodes into a reproductive frenzy. Coral polyps release millions of gamete bundles (eggs and sperm) into the water column via broadcast spawning, creating what looks like an upside-down snowstorm. Gradually, the gametes float towards the surface. Here, they burst open to allow eggs and sperm from different colonies to combine, forming larvae that will eventually grow into new corals.

Recreational and scientific divers flock to this area to see these massive and ancient coral colonies exhibit one of the world’s most visually-prolific mass coral spawning events. To make the most of your visit, consult the coral spawning schedule developed by sanctuary scientists.

Flower Garden Banks National Marine Sanctuary is accessible only by boat. Visiting divers should find an experienced dive charter boat to make the journey offshore. If you choose to take a private vessel, make sure you’re aware of sanctuary boundaries and mooring buoy coordinates. By following proper reef etiquette, all divers can help protect this vital and vibrant marine treasure.

More than three decades of scientific reports call for more protection of this unique area. Thusly, NOAA has recently proposed expanding the Flower Garden Banks boundaries. The expansion could add an additional 15 banks located off of the Texas and Louisiana coasts. This expansion would grow the sanctuary to more than 380 square miles. Extending protection to these additional locations will limit impacts from bottom-disturbing activities and safeguard vital habitats. The public can comment on the proposed expansion online until August 19, 2016.

Experience the wonders of Flower Garden Banks National Marine Sanctuary and other national marine sanctuaries at

By guest writers Allison Randolph and Elizabeth Weinberg, NOAA Office of National Marine Sanctuaries.