I grew up in Missouri, that’s a long way from the Gulf Coast, so it was always a real treat to sit at a seaside dive and order up a platter of fresh shrimp smothered in hot sauce, delivered directly from the fishermen anchored nearby. How things have changed. The local shrimp fishermen can still be found, but today 50% of the worldwide demand for shrimp and prawns is being met by industrial strength, commercial shrimp farming. In Shrimp Farming, a Cockail of Controversy (the second half of “The Future of Aquaculture”) we give you different perspectives, both problems and solutions on the sustainability of farmed shrimp.
Today approximately 3 million tons of farmed shrimp feeds the annual global market. About 75% of that production comes from Asia with Thailand exporting the most. Latin America farms the rest with Brazil, Mexico and Ecuador the leading producers.
Health Issues for You and the Environment
Shrimp are little bombs of cholesterol. Your total, recommended daily allowance is found in two servings of Pad Thai, one shrimp cocktail or a heaping helping of paella. And shrimp cause allergies, especially in children. But it’s the health of the environment that suffers the most from shrimp farming. (photo – wikicommons/narek75)
Shrimp Farming and Environmental Degradation
Wild shrimp need salt water and coastal mangrove forests are ideal habitats. Consequently, most shrimp farms are located in Asian tidal zones, mainly in Thailand, Bangladesh and China. Unfortunately, the very mangrove forests that shelter wild shrimp are being destroyed by commercial shrimp farms.
Nearly 40% of the world’s mangroves have been lost, including 70% of the mangroves along Ecuador’s seacoast. This is dramatic environmental degradation, because mangroves protect coastlines from storms; and their roots trap sediments flowing off the land and help to prevent coastal erosion. The disappearance of mangroves means an essential habitat for a variety of fish and other marine species is lost. (photo – Wikicommons/ferdous)
What Shrimp Eat?
Not only does shrimp farming threaten the health of its immediate environment but depletes marine populations from other areas. The sardines, anchovies and herring caught and fed to farmed shrimp means that these resources are no longer available to the larger fish, seabirds and whales who rely on these fish for their own continued existence. Some estimates claim that nearly 3 pounds of wild fish are required to produce one pound of farmed shrimp a ratio that can lead to serious over-fishing.
Shrimp raised in densely crowded farms can breed a variety of disease that can spread to wild shrimp. After testing “ready-to-eat shrimp, researchers found 162 different types of bacteria with resistance to 10 different antibiotics.”
Most farmed shrimp comes from countries that have no restrictions on contaminants such as dioxins, PCBs, and other chemicals that are banned from our environment. Nor are there restrictions on the use of hormones and antibiotics to counteract disease and to enhance growth.
Without the natural cleansing and filtering of mangrove forests, the shrimp farming ponds will accumulate a toxic sludge composed of excrement, pesticides and antibiotics. Over time this build-up can render the ponds unusable and attempts to return this environment to productivity may require decades. (photo – sludge at bottom of drained shrimp pond, Wikicommons)
Tiny shrimp have a massive Carbon Footprint!
Recent research published in Phys.org estimates that to produce one pound of frozen shrimp may put one ton of carbon dioxide into the atmosphere. Put simply, eating shrimp has a larger carbon footprint than eating beef! (photo – Narek75-wikicommons)
Wild Shrimp has its own problems!
Shrimp caught in the wild may be disease and antibiotic free however they are not delivered to your table without their own environmental impact. Wild shrimp are caught by trawling and that results in damage to sea beds and significant bycatch. Often the bycatch can make up half of what is netted and is simply thrown away an amount estimated to be about two million tons annually.
Are there Sustainable Solutions?
Ecological problems, disease outbreaks, and criticism from consumer countries have led to changes in industry practices and government regulations. In 1999, a program aimed at developing and promoting more sustainable farming practices was initiated.
The delta where the Mekong River drains into the South China Sea is one of Asia’s most productive areas. Along its banks, miles of mangroves were replaced by miles of rice fields and in the last two decades, the miles of rice fields have been replaced by miles of ponds built to farm shrimp. The once fecund jungle landscape has been utterly transformed and it’s not very pretty.
Shrimp farming does have benefits, local farmers now have concrete homes and maybe even a new car. However, is this new prosperity fleeting and does it come with substantial cost? (photo – feeding shrimp in Vietnam)
The Mekong Delta is a poster child for the destruction of mangrove forests. A recent study in Tra Vinj province estimates the rate of mangrove destruction at over 13% annually between 1995 and 2001, all attributed to shrimp farming. However, a recent initiative called Mangroves for the Future (MFF) is combining the efforts of NGOs, the government and local communities to regrow mangroves.
Growing Mangroves and Shrimp
Shrimp farmers are given incentives to maintain or regrow mangroves on at least 40% of their land. This style of farming, is called mangrove-shrimp poly-culture or “extensive farming” and is the opposite of “intensive” shrimp farming.
Normal intensive shrimp farming is one of the most unsustainable forms of aquaculture. In addition to causing mangrove deforestation, intensive farming also relies on feeding shrimp industrial fishmeal and treating shrimp with antibiotics to control disease. (photo – extensive shrimp farming in Mekong Delta, wikicommons)
In contrast “extensive farming” raises shrimp within the natural ecology of the mangroves forest. Since the shrimp breed and feed naturally they are less vulnerable to disease and antibiotics are not needed.
Extensive farming also makes economic sense. Intensive shrimp farming requires a huge investment and disease can wipe out an entire shrimp harvest in just two days consequently anything that lessens the possibility of disease is worthwhile. Read more about “extensive shrimp farming” at Mangroves for the Future.org.
In the United States “closed shrimp aquaculture systems’ are now being used. Growing shrimp inside avoids over-crowding and efficiently circulates the water. Shellfish are sometimes used to filter the water naturally. Closed shrimp systems are more environmentally sustainable and might prove to be an excellent alternative for Thailand’s large, commercial shrimp industries. See Wikipedia. (photo – fresh water institute)
Can Fake Shrimp Save the World!!
That’s a novel idea that New Wave Foods is working on, see this video for the details.
To Eat Shrimp or Not To Eat Shrimp?
The final choice to eat shrimp or not to eat shrimp is up to you. Hopefully we have given you sufficient data on the health effects and environmental impact of shrimp farming that will help you make an informed decision.
If you really need to order your Pad Thai with shrimp then we suggest that you do this as a special treat and not as a weekly staple. Both your health and the environment will thank you.
by Bob Frerck, Blue Ocean Network
Additional Sources for Related Articles
See these Blue Ocean posts on Sustainable Seafood:
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