Climate change is damaging coral reefs around the world, but this reef off the Texas coast is thriving
Some of the healthiest coral reefs in the world can be found in the Gulf of Mexico, about 100 miles (160 kilometers) off the coast of Texas. Protected in a deep, cool offshore habitat, the reefs at Flower Garden Banks National Marine Sanctuary feature an amazing amount of coral cover. But scientists say it, like all coral reefs, is fragile, and its location will only provide protection for so long in the face of a warming climate.
“Seeing so much coral in one place is truly remarkable — an experience that most people on a reef in this day and age don’t have,” said Michelle Johnston, acting superintendent and research coordinator for the federally protected area.
The reserve has seen some moderate bleaching this year, but nothing like the devastation inflicted on other reefs during record summer temperatures. However, Johnston said this is among her top concerns about the future of the shelter. Very warm water causes corals to expel their colorful algae and turn white. They can survive if temperatures drop but become more susceptible to disease and may eventually die.
Florida’s coral reefs — the third largest in the world — experienced an unprecedented and potentially deadly level of bleaching over the summer. So far this year, at least 35 countries and territories across five oceans and seas have experienced mass coral bleaching, said Derek Manzello, NOAA’s coral reef monitoring coordinator. He said it’s too early to know how much Florida’s coral reefs will recover, because coral may die after a year or two of bleaching.
“If you have severe bleaching events every year, the prognosis is not good because that basically means the corals won’t have a chance to recover,” he said.
Preserve officials say that even in occasional years when Flower Garden Banks has experienced more severe bleaching than this year, it has quickly recovered thanks to its overall health and depth, and is already recovering this year.
A report expected to be issued in the coming months will look at the reserve’s vulnerability to the expected impacts of climate change.
Manzillo said the banks of the Rose Garden stand out for the amount of coral cover they cover — averaging more than 50 percent in some areas of the reserve — compared to about 10 percent in the Caribbean and the Northwest Atlantic. Its reef is also located about 60 feet (18 m) below the surface and surrounded by deeper water, compared to many reefs where the reefs are found in shallow water just offshore.
The corals in the banks of the Rose Garden were able to thrive offshore because of mountain-like formations called salt domes, which raised the corals high enough to catch the light, Johnston said.
Divers travel from all over the world to see the reefs at Flower Garden Banks, where colorful fish, manta rays, sharks, sea turtles and worms that look like Christmas trees stream in and out of the reef.
Andy Lewis, a Houston attorney, said he knew from his first trip to the shelter about a decade ago that he “had to be a part of my life.” Luis became a dive director and is now president of Texas Caribbean Charters, which takes about 1,000 people a year on dive trips there, about half of whom make a return trip.
“It’s just a real adventure,” said Lewis, who also serves on the reserve’s advisory board. “I love the boat ride.”
“You go down and you’re above the live coral as far as you can see,” Lewis said.
Lauren Tynes, a nurse from Colorado, described how she was cliff diving this fall and how she was surrounded by a huge coral reef as schools of fish darted through. Long found the description apt: “It’s like a field of flowers,” she said.
Flower Garden Banks is one of 15 National Marine Sanctuaries and two National Marine Sanctuaries protected by NOAA’s Office of National Marine Sanctuaries, and the only one in the Gulf of Mexico.
The campus consists of 17 separate banks covering an area of 160 square miles (414 square kilometers). When it was designated in 1992, the sanctuary had two banks. Its largest and most recent expansion into 14 banks came in 2021, a process that included input from the advisory committee, which includes representatives of industries that rely on the Gulf, from oil and gas to entertainment to fishing.
Efforts like these are being made in hopes of reducing greenhouse gas emissions globally, Manzello said.
“We need all of these things to happen in concert to really take care of coral reefs over the next 20, 30, 40 years,” Manzello said.
Coral reefs support about a quarter of all marine species at some point in their life cycle. They are also economic engines. By providing healthy habitat for fish, they support commercial fishing as well as bring in tourism revenue.
“Because coral reefs are declining all over the world, when we find healthy reefs, we want to keep them that way,” said Kelly Drennen, education and outreach specialist at Flower Garden Banks. “And they serve as repositories of what could help restore some other coral reefs in the future.”
The banks of the Rose Garden were not damaged by the massive oil spill that followed the deadly 2010 explosion on the Deepwater Horizon drilling rig, but other reefs in the Gulf were. Data collected from the reserve’s deep habitat study is being used to help guide the restoration of those coral reefs.
Researchers are also studying the genetics of the Flower Garden Banks coral, including whether it is different from species found in Florida.
“The more knowledge we have, the better equipped we are to try to protect those coral reefs,” said Brooke Zurita, a senior biologist at Moody Gardens.