Texas Parks & Wildlife Magazine   


Underwater Oasis

Oil rigs and sunken ships provide priceless habitat for fish and other marine animals.

By Larry Bozka

What was an indistinct speck on the horizon only a half-hour ago has mushroomed into a steel leviathan, a colossal yellow beast that towers high above the Gulf of Mexico atop 200-foot-long legs. Still, compared to oil rigs farther offshore in much deeper water, this one is a mere adolescent.

Slathered across the structure's supports like a sloppy paint job, a long and spongy mat of avocado-green algae punctuates the waterline. Pulsating mops of grass are randomly attached to the platform's circular pilings, wobbling toward the east and belying the direction and intensity of the rushing offshore current.

My fishing buddy Dave Aitken gently taps the engine throttles. Twin 250-horse outboards growl in response. Slowly, the 33-foot center-console Deadline circles around the structure, its twin props spinning a brilliant wake of blue-and-white saltwater. No matter how often I look at it, I'm absolutely amazed by the seemingly infinite spectacle of life that continuously gravitates to these massive manmade structures.

Aitken points out a small but concentrated school of spadefish. They hover on the down-current fringe of the rig, their ebony dorsal fins slicing the surface with the circular commotion of a washing machine. The gracefully striped "angel-fish" nip and tug on the waving vegetation. Mixed in among them, chomping on barnacles glued to the rig's submerged crossbars, a hungry pod of sharp-toothed triggerfish takes impatient turns at the buffet line.

The chain of life continues progressively deeper. Halfway down, a couple of heavyweight fish are etching apostrophe-shaped Vs on the LCD depthfinder. Probably amberjack, we surmise. Farther below, suspended just off the bottom, small red snapper explore the platform's base, searching for a meal and hiding from creatures that would gladly make one of them.

In between, there's much, much more that we cannot see.

Scuba divers often explore platforms like this one. It's a heck of a lot closer, after all, than Belize or Cozumel, and on many gulf structures, the reef fish circus is every bit as entertaining.

If a person wants to see the gulf's bounty up-close and personal, it takes structure — hard substrate, in marine biology vernacular — to make it happen on a regular basis. Working production platforms are among the most popular of fish-finding destinations, but by no means the only.

Thanks to cooperative efforts between the federal government, the Texas Parks and Wildlife Department, other state agencies and the oil-and-gas industry, such destinations are now more numerous than ever. Artificial reefs, most commonly the carefully deconstructed remnants of petroleum production platforms, along with sunken decommissioned ships, provide the pieces for an incredibly productive maze of fish-holding structures that rest in Texas offshore waters.

On the whole, the gulf is a featureless expanse of sprawling mud bottom.

A 1989 study conducted by the Gulf of Mexico Fishery Management Council estimated the gulf's natural reef habitat to be only 15,000 square miles, less than a third of it located offshore of Texas and Louisiana.

Since their inception in the late 1980s, TPWD's Rigs to Reefs and Ships to Reefs programs have literally filled vital niches in the demand for offshore structure. Nearer to shore, programs to enhance suitable areas with concrete, rock and other hard materials have done the same. Along with working oil rigs, these meticulously executed enhancements are lending an invaluable assist to an incredibly broad spectrum of gulf species.

Says former TPWD Coastal Fisheries Director Larry McKinney: "When you have an ocean out there that is nothing but a big, flat mud plain, oil production platforms are vital to affording the kind of diversity we want. They provide a great fishery that we would not otherwise have. Those fish would not be there if the rigs, or in other cases reefs, were not there as well."

Some question the value of artificial reefs, arguing that the structures only concentrate fish and make them more vulnerable to angling pressure. However, according to the veteran biologist, research shows that manmade reef habitats more than justify their existence.

"For pelagic (ocean-going) species, artificial reefs definitely act as attractants," McKinney explains. "Those fish, constantly on the move, are looking for a structure and shade, be it from a floating shrimp boat, a rig or reef or even a floating mat of sargassum.

"But," he adds, "for the reef fishes, the groupers, the snappers and that type of species, reefs are not only providing habitat; they're also beginning to support the species they attract. Artificial reefs are not just attracting, but also growing fish — lots of fish."

Dale Shively, TPWD Artificial Reef Program coordinator, concurs with McKinney. "Once fish are attracted to a reef, they live on that reef and reproduce," Shively notes. "We have seen it with a number of species, including red snapper, black drum and other types of reef fishes.

"That doesn't mean that every fish uses that piece of artificial material at every stage of its life," Shively explains. "But we have repeatedly tagged adult fish and seen them return to reef sites after traveling a little bit, while yet other fish never left. We have found juveniles on those reef sites as well. Artificial reef structures are invaluable to a great many species."

According to Shively, the Rigs to Reef concept came together in 1989, when TPWD began working on an Artificial Reef Plan (PDF 3 MB). "So far," he says, "we have decommissioned and repositioned over 100 oil platforms through the Rigs to Reefs program.

"Gulfwide, the state legislatures at the time were recognizing a loss of valuable habitat when production platforms were removed and taken back to shore," Shively says. "Texas, with other gulf states, agreed to work with the Marine Mineral Service to develop the Rigs to Reefs concept. It moved quickly after that. Once the program was in place we began accepting platforms. We put the first one down back in 1994."

Essentially, Shively says, an oil company initiates the process by deciding to donate a structure to TPWD. "The company does all the work as far as reefing," he explains. "It doesn't cost us anything, and in return, we work out a donation amount. That figure is determined by comparing the cost of returning a rig to shore and cleaning up the ocean bottom as opposed to the cost of transforming the structure into a reef. The difference between the two figures is called a 'realized savings,' and we at the state get 50 percent of that difference as cash, along with all the materials.

"Rigs to Reefs is our bread and butter," Shively says. "It's a 'win-win' for both the oil companies and the state of Texas. We get the money, and we capture the material for marine habitat. And in most situations, the oil company comes out ahead financially."

In the case of larger platforms used to create brand-new sites, it's the norm to conduct a "partial removal." Says Shively: "The legs are cut mechanically, the upper platform is removed and, essentially, the legs are left standing in place. If an extra leg section is cut off below the deck, it is laid on the ocean bottom to add more habitat. That is the 'seed' for a site where we later tow in smaller structures to make the reef more complex."

Complexity, specifically the complexity of the material, is indeed important to the value of any given reef structure. "You don't put just anything down," Shively cautions. "It needs to be designed. We make sure that it's stable and durable, and complexity-wise, that it has enough structure variety to be beneficial. In any case, we want to create as many hiding places as possible for reef fish, as well as places where invertebrates and other organisms can build up a food chain. We already know for certain that a massive amount of biological growth occurs on the legs of oil platforms. That structure is already there, and unlike an artificial reef, we don't have to recreate the scenario."

The key to the success of TPWD's Rigs to Reefs program — and it has, by any measure, been successful — is to enhance and preserve what is already there. "Oil structures can be three-legged tripods or, instead, huge platforms with a dozen legs (called 'piles' by reef constructors)," Shively says. "Usually we will get an 8-pile platform, and it will come from a rig that has lived out its life in terms of production."

Typically, Shively receives a call from an oil company or through other venues discovers that a platform is being decommissioned. "The company works out the decommissioning procedures," he says. "Normally, they have to remove the structure, plug and abandon the well and then clean up the ocean bottom. Via a donation to Rigs to Reefs, however, they remove only the deck. We're only interested in the legs, the clean material. Most of the hydrocarbons are generated on the deck, so it's difficult to get them clean. Often, the oil company recycles the deck and sets it up with new legs elsewhere."

The legs of the rig form the foundation for a new artificial reef while the refurbished deck serves to complete the construction of a brand-new production platform. It's a large-scale case of industrial recycling, one that requires closely monitored cooperation between government entities and private businesses, and the end results are adding untold value to the Gulf of Mexico fishery.

TPWD's Ships to Reefs program has so far utilized a dozen WWII-era Liberty Ships. Most recently, in November of last year, the department sank the 473-foot Texas Clipper as an artificial reef off of South Padre Island. Rough weather conditions made the task extremely challenging. Although the ship ended up positioned at a less-than-ideal angle atop the gulf floor, engineers are currently working to correct the scenario. Meanwhile, the historic troop transport, luxury liner and research vessel is already assuming its ultimate role as another productive artificial reef in Gulf of Mexico waters.

The Texas Clipper sinking was a $4.5 million project. Future sinkings of this sort will hinge largely on public contributions, monies garnered from sport fishing, diving and other user groups, Shively points out.

"Nearshore public reefing, which began a year ago, is another component of the overall artificial reef project," Shively adds. "We create 160-acre reef sites in state waters close to metropolitan areas. Located only 6 to 9 miles offshore in 60 to 100 feet of water, they are placed within safe operating range of smaller boats.

"The public assists us with reefing materials to progressively enhance these locations, everything from concrete blocks to rocks to tetrahedrons engineered by commercial companies. One thing we do not use," Shively emphasizes, "is tires. They are unstable, they create limited growth and eventually, they end up washing up on the beach. They're really bad for beachgoers, the shrimping industry and the environment on the whole.

"We don't dump materials," Shively says. "We deploy them. And a whole lot of thought goes into the process."

The TPWD Web site contains extensive information about artificial reefing in Texas, including a downloadable file of the Texas Artificial Reef Plan (PDF 3 MB) and a current map of existing Texas reef sites. For more information, visit <www.tpwd.state.tx.us/landwater/water/habitats/artificial_reef>.

Even a cursory understanding of the working oil rigs and artificial reefs that rise from the bottom of the Texas gulf is more than enough to understand and appreciate their priceless value.

As a barely visible landmark, a thick patch of pixels on a depthfinder readout or an enormous Goliath looming a hundred feet above your boat, you'll never look at one of these structures the same way again.

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