Gulf’s Coral Reef Threatened By Non-Native Species

Aug. 19–The health of the Gulf of Mexico’s only true coral reef could be compromised by an invasion of a non-native coral species colonizing nearby oil and gas platforms, a federal report released Thursday has concluded.

This foreign species, native to the Pacific Ocean, is among a series of threats facing the Flower Garden Banks National Marine Sanctuary, a 385-acre underwater monument built over thousands of years by microscopic animals more than 100 miles off the Texas coast.

“We don’t want it on the reef,” said Emma Hickerson, the research coordinator for the sanctuary, of the orange cup coral. “We don’t know what the impact might be. If it is aggressive, it might (replace native coral).”

The good news is that the National Oceanic and Atmospheric Administration survey, which evaluated the health of reefs in 14 U.S. territories and the Pacific Islands, found the Flower Gardens to be one of the healthiest reef systems of those reviewed. But lingering concerns over the effects of nearby oil and gas exploration, increased fishing and boat traffic remain.

“We have to be vigilant. We can’t take it for granted that everything is fine,” said Hickerson, referring to the fragility of coral-reef systems, which are hubs of marine diversity that attract fishermen, divers and researchers.

If the coral dies, the whole system eventually crumbles.

“Anything we are doing out there may have some sort of cumulative effect on the resilience of coral,” Hickerson said.

Though the well-publicized effects of climate change, disease and coastal pollution ranked as the most serious threats to the coral reefs NOAA surveyed, the threats facing the reefs of the northwestern Gulf of Mexico are unique, and thus have not been well-researched. What toll they may take, if any, remains a mystery.

Since the report was completed, scientists have been troubled by additional signs of stress. In February, researchers spotted widespread symptoms of what may be white-plague disease — a bacterial infestation characterized by a white band along the coral’s edges.

“This is the first time we have had multiple colonies of multiple species affected,” said Hickerson. “In the past, we’ve seen what we have suspected as white plague out there but nothing that would alarm us.”

Luckily, recent surveys have indicated that the bacteria are not spreading.

Fresh water a threat Another concern surfaced in June, when Hickerson and a colleague discovered that fresh water from the Mississippi River, likely laden with fertilizers and other chemicals, had penetrated the Flower Gardens’ boundaries. Hickerson is not sure what effects that will have.

“There is definitely Mississippi water at Flower Garden banks,” she said. “We were under this false impression that we were not affected by that. Now, that could be another stressor.”

Given sanctuary status in 1992, the Flower Gardens is one of the only natural reef systems in the Gulf and the northernmost reef in U.S. waters. Though there are other areas in the Gulf that have coral, the Gardens and the McGrail Bank, east of the sanctuary, are the only ones actively growing, Hickerson said.

Diving industry worried In the four-mile area that is home to the protected East and West Flower Garden Banks and Stetson Bank, there are 14 production platforms and 178 kilometers of pipeline, the report notes. The platforms are homes to massive colonies of orange cup coral, an invasive species first documented in the Flower Gardens in 1992 when an unknowing diver took a photograph of it.

Last year, 46 colonies of orange cup coral were removed from Geyer Bank, a coral mass about 12 miles east of the East Flowers.

Only one of the platforms lies within the sanctuary. Erected in 1981 and purchased by Houston-based W&T Offshore, Inc., in 1999, High Island 389 is covered with orange cup coral and home to a diverse array of marine species that make it a frequent stop for divers.

“We are very concerned about this. We are very cautious and cognizant of what is going on down there,” said Manuel Mondragon, a company spokesman.

Besides native coral, the possible spread of an aggressive invasive species could devastate the local diving industry.

A survey of charter-dive operations in 1997 found that an estimated 2,350 divers visited the Flower Garden Banks.

That year, they spent about $870,000 in Texas, the majority in Freeport, where many of the charter operations are based.

“If the coral dies, we are gone basically,” said Sharon Cain, who has owned Gulf Diving LLC in the seaside town since 2002. The charter runs multiday trips to the Flower Gardens throughout the year.

‘Living together’ Cain, however, said she is encouraged by recent reports that the white-plague disease is not spreading. Thus far, she said, none of the orange cup has been seen on the Flower Gardens.

The same geological forces that created the mass of oil and natural gas that energy companies seek beneath the Gulf of Mexico caused salt domes to lift, forming the banks on which the coral of the Flower Gardens attached and flourished.

Even today, there remains a relationship between the industry and nature.

Platforms, like coral reefs, attract a diversity of marine organisms. And when they are retired, many are toppled to create artificial reefs.

“We have been living together for 10 to 20 years now,” said Mondragon, referring to the estimated 6,500 platforms dotting the Gulf. His company operates more than 250.

A possible solution The Texas Parks and Wildlife Department, which converts abandoned platforms into artificial reefs in the Gulf, said Thursday that if the orange cup coral posed a threat to the sanctuary, the department could move platforms inundated with the species out of the area.

“It may be a consideration if it indeed was deemed a problem,” said John Embesi, an artificial-reef biologist with the department, of the relocation. “We’ve done it with other problem species.”

LEARN MORE

To access NOAA’s 2005 State of Coral Reef Ecosystem Report, log onto: http://ccma.nos.noaa.gov/ecosystems/coralreef/coral_report_2005

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