Take a High Plains cattle feedlot – with all of its excrement, antibiotics, disease, parasites and other filth – cram it into a net, and anchor it 50 feet beneath the surface of the ocean. Replace the cattle with fish, stir, and you’ve got something called “open ocean aquaculture.”

These facilities are to the sea what huge livestock operations are to the land. Hundreds of thousands of fish – such as tuna, cod, halibut and red snapper – are raised in gigantic submerged nets or cages. The resulting clouds of feces, uneaten feed, antibiotics, toxic metals, pesticides, and other pollutants ruin water quality, sealife habitat and the environment in general.

Fish excrement can build up on the ocean floor, making it uninhabitable to some sealife up to 500 feet from the cages.¹  These “nutrients” can also cause eutrophication, when sheets of algae rob marine life of light and oxygen – killing fish and poisoning shellfish.²

On the Loose

Another potential danger is “escapement,” when farmed fish break free of their nets – whether due to storms, shark attacks or other factors – spreading diseases and parasites to wild fish, and stealing their food sources.³

The use of genetically modified fish in aquaculture is also a threat, as 35 such species are now in development – including trout, tilapia, salmon, halibut and Arctic charr.⁴   The National Research Council has determined that transgenic fish represent the “greatest science-based concerns associated with animal biotechnology.” Released into nature, these creatures could spread undesirable genes, out-compete and overwhelm wild populations, and become difficult or impossible to eradicate if necessary.⁵

Supersize It

Aquaculture may also worsen overfishing. Many fish raised in offshore fish farms require a heavy diet of fishmeal and fish oil. Up to five pounds of wild fish, such as anchovies and sardines, are needed to feed one pound of farmed fish.⁶  These populations are already being harvested to the brink.

Uncharted Waters

Despite serious concerns surrounding offshore fish farming, the Bush administration’s National Oceanic and Atmospheric Administration – a federal agency that has been promoting aquaculture – has refused to analyze the environmental impact of allowing fish farms in federal waters.⁷   Instead, the administration is charging blindly forward, unwilling to consider the consequences turning over our seas to the destruction of these massive, polluting cages.





Footnotes

¹ Goldburg, Rebecca J. et al. Marine Aquaculture in the United States: Environmental Impacts and Policy Options. Pew Oceans Commission, Arlington, VA, 2001.
² Scottish Association for Marine Science and Napier University. “Review and Synthesis of the Environmental Impacts of Aquaculture.” Scottish Executive Central Research Unit, Scottish Executive, 2002. ; Goldburg.
 ³ “Comments Dissenting from the Aquaculture Effluent Task Force Subgroup on Nonnative Species.” Letter from Tracie Letterman, Center for Food Safety, Washington, DC, to Marta Jordan, Office of Water, U.S. Environmental Protection Agency, Jan. 8, 2003.
 ⁴ “Genetically Engineered Fish.” Center for Food Safety, Washington, DC.
 ⁵ Borgatti, Rachel and Buck, Eugene H. “Genetically Engineered Fish and Seafood.” Congressional Research Service, Dec. 7, 2004.
 ⁶ Naylor, Rosamond L. et al. “Effect of Aquaculture on World Fish Supplies.” Nature, 405:1017-1024, 2000.
 ⁷ U.S. Code, Title 42, Section 4332, subsection (C)