Electrifying Coral Growth: promising artificial reef project in Florida

Electricity - long before we learned that all animated objects generate some level of electrical current or field, it was viewed as a source of life from the gods or god.  Bolts of lightning brought Mary W. Shelley's monster to life in Frankenstein, and a good jolt or two has saved more than one individual thanks to the emergency defibrillator.

But those are big, powerful doses.  At very low levels, electricity can also be a source of life.  An example of which would be the use of very low-level voltages to stimulate coral growth.  This has been used with artificial reefs in several parts of the world, and it is now being tried in Florida's Lauderdale-By-The-Sea.  Not far off the town's coastline are reefs easily accessible to divers, in 15 feet of water, 250 yards off shore.  Six years ago, the town leaders, realizing that an expansion of their reef system would be good for conservation and tourism by both establishing new attractions for divers and providing some relief from "diver pressure" on existing natural reefs, commissioned the non-profit Global Coral Reef Alliance to install a steel rod framework that is electrified at very low levels through solar panels.  

The low levels of electricity stimulates calcium carbonate - the foundation of all coral reefs - to bond onto the steel rods (the framework resembles an aircraft hanger in shape).  The stimulation forms a substrate that is conducive for a wide variety of sedentary marine creatures, form corals to oysters.  It also provides a platform for the attachment of living coral that has either off from natural reefs or has been nurtured in a laboratory or aquarium setting.

Electrical stimulation of calcium is also being used for humans.  Low-level stimulation has been shown to accelerate bone growth and successfully used with patients following orthopedic surgery.  In this oceanic application, pioneered by Global Coral Reef Alliance's Thomas Goreau and patented under the name Biorock, it works in a very similar fashion and, while it does have some detractors who question it's effectiveness, for Lauderdale-By-The-Sea, it appears to be working.

“It’s definitely attracting fish,” said Stephen Attis, president of Vone Research which did the actual installation. “The structures are growing calcium carbonate. The amount of oysters on it and how fast they’re growing is amazing. It’s very promising.”

Promising, yes.  But no one is expecting a full-fledged coral reef overnight.  A fully formed reef will still take many years, if not decades, to be realized.  But given the precarious state of the world's coral reefs due to climate change, pollution, and other man-made activities, any effort that provides coral reefs with some sort of assistance while we address the need for a defense against those threats that jeopardize coral's survival - well, that's a welcome little jolt.

“This is a really neat project and I believe it’s going to work,” Attis said. “We’re already seeing growth, and once we transplant corals, it’s really going to change. It should be exciting.”

Source: Sun-Sentinel

Navy Target Practice: groups object to contaminated sunken ships

Around the globe, artificial reefs are being established by preparing and sinking ships that have surpassed their useful life at sea.  Decommissioned and potentially headed for the scrapyard, as artificial reefs, these vessels serve several purposes.  As an artificial reef, they can offset some of the natural reef that has been lost to coral bleaching or due to pollution from shoreline development.  They also serve as attractions for dive tourism and can, in some cases, reduce "diver pressure" on natural reefs by luring divers to dive on the sunken ship rather than the actual reef itself.

These artificial reefs have been the result of extensive effort by various organizations to procure and prepare these vessels so that they are not only diver-safe but, most importantly, environmentally safe.  They are thoroughly cleaned of any material, residue, or chemicals that could contaminate the marine ecosystem where they are placed.

Unfortunately, not all vessels end up in the scrapyard or as artificial reefs.  The U.S. Navy, through a warfare practice exercise called SINKEX (sinking exercise), has used old inactive naval vessels for target practice and the activity has raised the ire of ocean conservation groups to the extant that several groups, including the Center for Biological Diversity, the Sierra Club, and the Basel Action Network (BAN), have filed a complaint with the Navy and the EPA in the hopes of stopping another planned exercise this summer, north of Hawaii.  The main issue: the vessels are not decontaminated and pose a significant hazard to the oceans; they are simply treated as "out of sight, out of mind."

The Center for Biological Diversity issued a press release today that highlights the primary concerns.  It included:
"Based on documentation of known contaminants found in more than 100 ships sunk by the Navy over the past 12 years, the ships are contaminated with toxic heavy metals and polychlorinated biphenyls (PCBs). Sinking — instead of recycling — these ships will send toxic chemicals into the marine environment and needlessly deprive the U.S. ship recycling industry of both resources and jobs.

'PCBs have been banned globally because they're some of the most dangerous pollutants around,' said Emily Jeffers of the Center for Biological Diversity. 'They leach from sunken ships into the ocean and accumulate in the bodies of fish, dolphins and whales. Our oceans should never be used as a dump for poison.'

The EPA and Navy admit that highly toxic chemicals are released into the marine environment as a result of SINKEX, including asbestos, lead paint, antifouling paint containing tributyltin (TBT), polybrominated diphenyl esters (PBDEs) and PCBs, a suspected carcinogen that has been targeted for global phaseout and destruction under the Stockholm Convention. However, the EPA and Navy seem unwilling to consider the new scientific findings presented by the coalition that show the amount of PCBs and other pollutants from the scuttled ships is far greater than EPA believed when it exempted SINKEX from ocean-dumping laws. Instead the EPA asked a federal judge to dismiss the complaint on procedural grounds — a request that was denied last week.

'The sinking of these vessels directly contradicts President Obama’s directives calling on federal agencies to lead by example in recycling and ocean stewardship. The pristine waters north of the island of Kauai have already become a graveyard for more than a dozen ships containing untold tons of pollutants. These sinkings must stop! This is not ocean stewardship, nor is it the action of a 'Great Green Fleet,' ' said Robert Harris of the Sierra Club in Hawaii.

I for one am not opposed to the target practice exercise per se, as long as the vessels have been properly scrubbed.  If that is not economically feasible for the Navy, then the ships should be scrapped - a more environmentally sound move that also supports the scrapyards, a private industry that is need of work in these difficult economic times.  For the EPA to give the Navy a pass on decontaminating the ships and dispatching them to the bottom of the sea is unacceptable and smacks of the same short-sighted thinking that went into the concept of dumping nuclear waste at sea.  No, the ocean isn't that big that nobody or no marine life will notice.

To add the voices of the general public to this issue, the Center for Biological Diversity has a petition available for signing.  Also, the latest legal complaint can be read here.

Source: Center for Biological Diversity

Florida's Tire Reef: 70's artificial reef proves to be a very real failure

Artificial reefs serve as a possible remedy for natural coral reefs that have been damaged either by pollution, temperature (in the form of coral bleaching), or too much manhandling from snorkelers and divers, just to name a few. They can provide new habitats which can increase the populations of fish, from local reef fish to larger pelagics, and they can take some of the pressure off of a reef enhancing the reef's ability to rejuvenate.

Scientists, conservation organizations, and groups invested in tourism are looking for new methods and materials for establishing artificial reefs. Two of the most common artificial reef formations are sunken wrecks and concrete structures, sometimes referred to as "reef balls." Wrecks have been around since man has sailed the seas and there are many which serve as unwitting artificial reefs. But today, we find organizations that take decommissioned vessels, clean them of any potential pollutants and deliberately sink them. These wrecks could last from 50 to 100 years or more and in that time, a substantial reef structure can form - one that could possibly outlive its original foundation.

Reef balls, basically made of concrete and other ground up substrate that can provide a firm base for coral growth, are perhaps less mysterious than sunken wrecks and a bit more plain-looking. However, they can provide a very natural-like foundation for a coral reef and, given time, they can look for all to see, including man and animal, like any other natural reef given enough time for coral and sea grasses to take hold.

There have been other candidates for artificial reefs. Along the California and Gulf coasts, retired oil rigs are being debated as potential artificial reefs when the upper superstructure is removed to just far enough below the surface so as not to pose a shipping hazard. Other structures have become artificial reefs sometimes by accident. In San Diego, California, the NOSC (National Oceans System Center) closed down a research tower situated about a mile offshore, in the late 80s, and was preparing to turn it over to the Scripps Institution of Oceanography. Unfortunately, before Scripps could take possession, heavy storms came in and knocked it over: a loss to Scripps but a gain for local mussels, anemones and a wide variety of local fish - not to mention local scuba divers who now had a new underwater attraction to break up the wide, sandy vista of San Diego's Mission Bay.

But not all artificial reefs have been successful, regardless of the best of intentions and considerable thought put into the design. Not everything that mankind makes can become a suitable foundation for a reef. Case in point, the disastrous Osborne Reef off the coast of Ft. Lauderdale, Florida.

In the early 70s, Broward Artificial Reefs, Inc. proposed an extensive artificial reef consisting of discarded tires. The supposed benefits would be the elimination of unsightly, old worn tires and the chance to entice more game fish for recreational fishing. The project was endorsed by the U.S. Army Corps of Engineers and, with the aid of many private, commercial and even naval vessels, the Broward County government deposited over two million tires, bound together with steel clips, cables, or nylon rope, across 36 acres. A new artificial reef seemed to be on its way.

But it was not to be. The securing cables, clips and ropes corroded and the lightweight tires were now on the move. Pushed around by currents and storms, the tires smashed into living corals as they spread out like an ever-increasing steamroller. After one particular storm, thousands of tires piled up against a reef, while others made their way to local beaches.

Even if the tires had managed to stay together, it turns out that they were not a good platform for reef growth due to their flexibility and the fact that, as the rubber breaks down from long exposure to sunlight and seawater, several low-level toxins are given off which have the potential to stunt the growth of sealife.
"The really good idea was to provide habitat for marine critters so we could double or triple marine life in the area. It just didn't work that way," said Ray McAllister, a professor of ocean engineering at Florida Atlantic University who was instrumental in organizing the project. "I look back now and see it was a bad idea."

Reef Rescue videotaped the condition of the tire reef in 2010:


From time to time efforts have been made to salvage the tires. State campaigns have been put in play, often supported by the military (Navy divers have used the cleanup as part of their training), but the cost is enormous and so progress has been in fits and starts. The military has scaled back their involvement as their resources are being taxed by two wars and looming budget cuts. To date, around 73,000 tires have been recovered - a considerable number, but with the original number totaling over 2 million, there is a long ways to go.
"We've literally dumped millions of tires in our oceans," said Jack Sobel, director of strategic conservation and a marine scientist for the Ocean Conservancy scientist, when speaking about the concept of tire reefs on a worldwide scale. "I believe that people who were behind the artificial tire reef promotions actually were well-intentioned and thought they were doing the right thing. In hindsight, we now realize that we made a mistake."

We are now getting to a point with the condition of the oceans and marine ecosystems where there is less tolerance for "experiments" and a greater need for solutions for which we are much more certain about the outcome. Unfortunately, our actions that adversely impact the marine environments are bad enough; we can't afford to have our solutions simply add to the problem.

Read more about the history of Osborne Reef.
Read more about the reef in 2007 in USA Today.
Read more about cleanup efforts in 2010 in Reef Rescue.