23 July 2011

What are Artificial Reefs?

The National Fisheries Enhancement Act of 1984 (NFEA) defines an artificial reef as “a structure which is constructed or placed in water…for the purpose of enhancing fishery resources and commercial and recreational fishing opportunities.”1 There are 14 Gulf and Atlantic States with active artificial reefing programs. Florida alone has 2,400 artificial reefs comprised of sunken cars, buses, tanks, tires, oil rigs and ex-military vessels.2 The Delaware Artificial Reef program boasts of their 4 ex-military vessels, 10 tugboats and barges, 86 tanks and armored personnel carriers, 1,100 New York City subway cars and 8,000 tons of ballasted truck tires3 now resting in the Delaware ocean dumping ground that covers approximately one square mile of ocean floor.

States are turning to materials of opportunity as a low cost reef solution to attract fish and bring economic benefits to coastal economies through increased fishing and diving opportunities. However, these materials of opportunity, which include Navy and MARAD ships, are essentially waste products, often with toxic residues. Their use is often perpetuated by those that have a waste disposal problem to solve. "The artificial reefs have been sold by a number of specific interests that benefit from them," said Jack Sobel, former director of strategic conservation science and policy at the Ocean Conservancy in Washington, D.C. "The oil industry in the Gulf of Mexico, the sports-fishing and recreational-diving industries up and down both coasts, and the people who need to dispose of old cars, bridges and boats, all make out better than the fish and sea anemones do."4

Most artificial reefs are developed in areas with featureless bottom topography.5 These artificial reef sites alter the natural habitat in order to attract fish for increased economic benefits. “At the very least, we are altering marine habitat by sinking ships - somewhat akin to gathering a bunch of old wreck cars in the midst of a forest or grassland. This would create habitat for certain species (e.g. rats), but would definitely alter the natural ecology.”6

The real benefit is to fishermen’s ability to more easily catch fish, making the sea floor more interesting to divers and provide a cost-effective waste disposal site for those in need of dumping large volumes of waste material.

The only proven impact of artificial reefs is that they attract fish and concentrate populations for rapid harvest. The Gulf States Marine Fisheries Commission (GSMFC) suggests that concentrated populations themselves may lead to overfishing and the decline of species within the vicinity of the reef site.7 The attracting nature of the reef may actually be detrimental to species populations, as overfishing at target sites rapidly eliminates fishery resources, and soon thereafter, all related economic benefits once attributed to sports fishing and diving tourism. Clearly, when the fishery is closed due to overfishing, so too will be the local businesses that are dependent on fishing and diving tourism.

1 National Fishing Enhancement Act of 1984, Title II. Appendix B, Artificial Reefs, Public Law 98-632
5 Stone et al. 1974
7 Lukens, R.R. and Selberg, 2004

The Ex-Vandenberg was sunk in the Florida Keys National Marine Sanctuary in 2009 at a cost of $8.6 million. 
The vessel is a popular fishing destination as it is said to attract fish away from the protection of natural coral reefs within the marine sanctuary itself. However, it is well known that fish aggregation at a marked site can exacerbate the problem of overfishing, as concentrated fish populations can be easily and more rapidly harvested.
Image Source: Stephen Frink/Florida Keys News Bureau

In 2001, New York City Metropolitan Transportation Authority (MTA) offered up 1,300 Redbird Subway cars and disposed of 23 million pounds of scrap metal on the ocean floor, saving a reported $11 to $13 million in disposal costs. 
The so-called savings was based on estimated costs for proper remediation and land-based disposal of asbestos and other related materials, which the MTA avoided by simply dumping at sea. To date, MTA has provided more than 2,500 retired subway cars to Virginia, Georgia, South Carolina, Delaware, New Jersey and Maryland for artificial reef projects.
Image Source: Virginia Marine Resources Commission

Source: DISHONORABLE DISPOSAL: The Case Against Dumping U.S. Naval Vessels at Sea; By Basel Action Network. July 2011

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