April 21, 1997 - Week 16
International Year of the Reef

When Coral Reefs Get in the Way . . .

High volumes of ship traffic occur in close proximity to sensitive coral reef ecosystems around the world. Therefore, it is not surprising that large ships run aground periodically, causing extensive damage to valuable reef resources. Within the United States, coral-rich marine protected areas have had their share of groundings. In August, 1984, a 400-foot freighter, M/V Wellwood, ran aground in the Key Largo National Marine Sanctuary transforming a colorful, vibrant reefscape into a barren, underwater parking lot strewn with limestone rubble. On October 25, 1989, a 155-foot ship, M/V Alec Owen Maitland, ran aground on shallow coral reef in the same sanctuary. By the time the Maitland was removed from the grounding site, more than 1,600 square meters of formerly pristine coral reef were totally or partially destroyed. Seventeen days later, the M/V Elpis ran aground, also within the Key Largo National Marine Sanctuary (now part of the Florida Keys National Marine Sanctuary [FKNMS]).

In response to these accidents, and in order to minimize physical and biological damage to the world's second largest barrier-type reef, the United States Congress designated an "Area To Be Avoided" by vessels longer than 50 meters as they transit the FKNMS. Unfortunately, this measure has not eliminated groundings in the sanctuary. On February 2, 1997, the containership, Contship Houston, ran aground in the FKNMS. An extensive coral salvage operation is currently underway to glue fractured coral heads together, and right corals and sponges which were overturned during this most recent grounding.

Restoration activities

Although many future groundings could be avoided through improved navigational technology and education of mariners, it is unlikely that grounding events will ever be eliminated entirely. Therefore, the restoration of the physical and biological integrity of damaged coral reefs will continue to play an important role in the maintenance of healthy coral reef ecosystems.

At the Elpis and Maitland grounding sites, efforts have been made to repair damaged coral reef resources through structural and biological restoration. Collaborative work between the National Oceanic and Atmospheric Administration and marine engineering contractors resulted in the development of structural restoration plans for both sites. At the Maitland grounding site, innovative pre-cast concrete modules, or Reef Replicating Armor Units And Living Foundations (RRAULF units), weighing approximately 9.5 tons each, were placed in the blowholes created by the ship. Forty RRAULF units were used to replicate the physical structure of the original reef, thereby creating a hard surface upon which the larvae of stationary reef organisms, such as sponges and coral, could settle and grow. At the Elpis site, the blowholes were filled with large limestone boulders and sand. Structural restoration at both sites was completed in the summer 1995. In the summer 1996, FKNMS biologists began the biological restoration (i.e., active transplantation of sponges, and hard and soft corals onto the surfaces of the RRAULF units and boulders). These biological restorations are attempts to "jump-start" the natural biological recovery process at each site. A multi-year monitoring program has been in place since 1993 to develop baseline data, and to assess the health of the injured areas before, during, and after the structural restoration. So far the restoration efforts appear successful, however, it will take several years to confirm that the slow-growing marine organisms find their new environment suitable.

Moving coral out of harms way

Transplanting coral and other sessile marine organisms as part of a larger reef restoration project is not the only practical application of this technique. In addition to the unintentional damage caused by ship groundings, species-rich coral reef communities also find themselves in the path of marine construction projects. However, unlike ship groundings, in the case of planned projects marine organisms can be moved to safe locations before they are destroyed. For example, large-scale coral transplants have been conducted in order to minimize damage to coral reef from the construction of a ship pier in Mexico, a navigation channel in Thailand, and a harbor in Palau. In Hawaii, nearly 14 tons of live coral were transplanted in Kawaihae Bay, in order to mitigate coral loss during a small boat harbor construction project. Although the success rates of large-scale coral transplants are varied, transplanting is becoming an important tool in the effort to save coral reefs.

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IUCN - The World Conservation Union and the US Department of Commerce’s National Oceanic and Atmospheric Administration (NOAA) are working together to publicize the urgent need for conservation and sustainable use of coral reefs as part of the International Year of the Reef (IYOR). The IUCN - NOAA partnership will heighten public awareness by providing a coral reef story idea to international media outlets each week throughout the IYOR. To provide story ideas which highlight coral reef issues of local, national, regional and international importance, IUCN and NOAA are in contact with NGOs, coral reef scientists, government officials, inter-governmental organizations and others to submit story ideas for possible use in the media outreach program.

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