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Fish Farming
http://www.enn.com/news/2003-08-08/s_7332.asp
OSLO, Norway - Fish farming, a growing global industry, can be a major contributor in feeding the world's hungry and help fight poverty, fishery experts told an international conference Thursday. An increasing number of people depend on aquaculture - the farming of fish, crustaceans and aquatic plants - with some 1 billion people satisfying protein needs from eating fish, researchers said. "Aquaculture is the only way to fill the gap between growing demand and supply in the future," Jiansan Jia, from the U.N. Food and Agriculture Organization, said. As wild fish stocks continue to dwindle, often due to overfishing, fish farming has increased in importance, Jia said at the opening of the meeting in Trondheim, 500 kilometers (310 miles) north of the capital, Oslo. Aquaculture provides about 36 percent of people's daily protein intake - 4 percent more than in 1970 - and is growing annually by 10 percent, providing more jobs, he added. It is the world's fastest growing food industry that uses animals as raw materials, with most of it on small, family owned farms, while industrial aquaculture accounts for just 13 percent of total world production. It is well-suited to poor, rural areas, according to Rohana Subasinghe, a U.N. fisheries resource officer. "The potential contribution of aquaculture to rural development, food security, hunger eradication, poverty reduction and national economic development is enormous," Subasinghe said. "We used to say 'aquaculture development,' but we should say 'aquaculture for development.'" But the industry is plagued by environmental issues, health hazards and debt problems as companies strive for mass production. Environmentalists and the industry agree that the use of animal antibiotics and dioxins in farmed fish pose health concerns, seabeds are damaged by fish cages and farmed fish that escape can harm wild stocks. In Norway, the second-largest seafood exporter in the world, banks have taken over the management of more than half the country's largest fish-farming outfits after debt defaults. The Nordic country of 4.5 million estimates that its seafood operations last year were worth some 11 billion kroner (US$1.5 billion), largely due to aquaculture. Some 150 experts from 50 countries were at the five-day meeting in Trondheim to discuss how to raise safety standards of producers worldwide, improve profits and better plan aquaculture. |
#2
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Fish Farming
Eating Responsibly: The Future of Seafood Farming
(From Winter/Spring 1999) by Nano Riley Americans are becoming a nation of fish lovers. Local supermarkets dazzle shoppers with tempting displays of creamy-white flounder and cod, rosy salmon filets or mounds of shrimp heaped over ice and garnished with lemon slices and parsley. These eye-pleasing arrays of the sea’s bounty are designed to tantalize, and it works. Seafood sales are soaring. With the exception of a few major port cities, such a variety of fish would have been unheard of a few years ago, yet today it is quite routine. Because seafood is low in saturated fat and easy to digest, it has become a staple on the dinner tables of the health-conscious. But as more and more concerned diners are choosing seafood as a better source of animal protein, our fisheries are stretched to the limit. Salmon, cod and other cold-water species, rich in health- promoting Omega-3 fatty acids, are nearly gone from the Atlantic. Fisheries are Declining Today, stringent regulations designating specific times and quotas for the fishing industry in waters all around the United States are in place. Still, the decline of fish populations in the world’s rivers and oceans continues at an alarming rate due to overfishing, water pollution and shrinking habitats for breeding grounds. The Grand Banks, one of the richest sources of seafood for centuries, is nearly depleted and is closed to most fishing, and sharks, swordfish, giant marlin and other great billfish are in serious trouble—too often they wind up caught in the mammoth nets of seagoing factory boats. In 1996 Greenpeace released a report stating that roughly one percent of all the world’s fishing vessels accounts for 50 to 60 percent of the global fish catch. High-tech fishing methods allow huge catches, and factory trawlers with the ability to haul in thousands of tons of fish and process them for market right on the boat now challenge small, independent fishing economies that support 20 million people worldwide. Clearing miles of mangrove and coastal marshland for beachfront housing, hotels and sea walls destroys natural nurseries for fish, shellfish and birds. The resulting beaches may be further "improved" by dredging up new sand to increase beach width, further stressing coastal life. In addition, pollution from industry and urban sprawl deeply affects water quality. Areas with high concentrations of urban runoff result in deformed fish and habitats laced with toxic chemicals. Recent studies found some Great Lakes fish contained high levels of PCBs—0.3 to 5 parts per million—as did human breast milk from mothers in the area. It was enough to keep ranch mink that ate Great Lakes fish from reproducing. Certain forms of pollution also lead to explosive algae growth, depleting the supply of oxygen and making the surrounding water uninhabitable. All this makes farm-raised fish very appealing to consumers. Ideally, fish raised in a controlled environment should be free of pollutants and ought not to place stress on the native stock. Indeed, many fish and shellfish are successfully farmed, providing a viable alternative to seafood caught in rivers and oceans. But as aquaculture expands to fill the tremendous demand for fish, it raises questions. Enter Aquaculture Aquaculture (literally "water culture") produces fish and shellfish for food in a closely managed habitat. Polynesians used aquaculture in the Pacific for hundreds of years by closing off entryways to lagoons. Once trapped, the fish were raised for food. Northern Europeans, Asians, Native Americans and most native peoples who lived near the ocean or along large rivers plentiful with fish also practiced aquaculture. Seaweed, bait fish and tropical fish for aquariums have been raised this way for years. It’s an old practice, but one that gets both positive and negative attention from environmentalists these days. Today the aquaculture industry is experiencing explosive growth, and at this point deserves a hard look to keep it on a positive track. Globally, China and Japan lead the world in the aquaculture explosion because of their centuries of experience. But recent statistics show the United States isn’t lagging far behind. Production of farm-raised fish in the U.S. tops 400,000 metric tons and generates over $729 million in revenue, placing it fifth in the world market. The government also promotes aquaculture, allotting more than $60 million in financial aid for fish farms in 1994. Consumers pay a high premium for farmed fish, and with the increased demand for seafood, aquaculture is becoming an ideal get-rich-quick scheme. Do-it-yourself magazines feature ads for fish farming in your own backyard as a full time occupation, or just an extra money-maker. But the big bucks come with the big farms, the ones operated by the shrimp barons who hope to cash in on that shrimp cocktail or catfish dinner enjoyed by seafood lovers everywhere. Unfortunately, too much of it smacks of a boom-town industry controlled by entrepreneurs whose resource-depleting methods resemble the slash-and-burn farming of tropical forests. How Fish Are Farmed On a fish farm, finfish and shellfish are raised in fresh or salt water ponds, tanks or raceways, and netpens or cages. Raceways are a series of tanks equipped with flowing water, while netpens and cages are usually placed directly into a natural body of water. Catfish farming makes up 50 percent of the U.S. aquaculture industry. The life of a catfish is much like that of a cow on a Midwestern feed lot. Its parents are breeder fish whose sole purpose in life is to produce delicious little catfish. The fertilized eggs are placed in hatching tanks with controlled heat and oxygen regulators, and about three weeks after hatching, the young catfish "fry" move to outdoor ponds to grow. One major advantage of fish farming is the farmer’s complete control of the environment —from the quality of pond water to the specially formulated fish diet. Control is the operative word here—fish farmers believe it is this element that gives farm-raised fish a guaranteed wholesomeness. Part of this control involves using products to prevent health problems in the fish. Thus, farmers use disinfectants to kill bacteria, herbicides to kill excess vegetation in ponds, vaccines to prevent infection, and drug-laced fish food to control parasites and other diseases. As a result, farmed fish may have the same chemical residues of hormones and drugs found in cattle. Effluent from fish farms may also invade the surrounding environment, and that’s a big concern. Environmental Problems On the surface aquaculture appears to be a pollution-free industry, but a closer look reveals the densely stocked ponds and tanks generate large quantities of polluting wastes, just like other forms of intensive animal production. While livestock raised on land produce waste that enters nearby lakes or rivers indirectly, fish farms often release effluent from ponds or tanks directly into nearby bays or rivers. The waste is mostly uneaten fish feed and excrement high in nitrogen and phosphorous. When this nutrient-rich waste reaches the water, it may cause oxygen-depleting algae blooms, resulting in a kill-off of wild fish and other water-dwellers. Occasionally, farmed fish escape and mate with native fish in the nearby region. This negatively affects the gene pool of wild fish, making progeny more vulnerable because farm raised fish are not bred for survival. While this may not seem like much of a problem, experts say this kind of interbreeding can weaken an already threatened species. Sometimes exotic species can also bring their own form of invisible baggage. For example, Japanese oysters imported for oyster farms brought with them diseases and non-native plants that threaten native oyster species. The Salmon Controversy Today, farming salmon is a flash point between environmentalists and fish farmers, particularly in the Northwest. Once salmon were plentiful in the Atlantic and the large rivers of the Pacific Northwest, but the Great Depression changed all that. During the 1930s, when Atlantic salmon was still so abundant, it was a cheap source of protein, a one-pound tin costing about ten cents. Americans grew dependent on this nutritious and inexpensive fare, and those lean years almost wiped out the entire North Atlantic salmon population. In the Northwest, dam-building fever nearly ended the great Columbia River runs, a run greater than that of all the rivers of Oregon and California combined. In 40 years, 36 dams were built on the Columbia and its tributaries, forcing salmon nowadays to navigate huge dams through the famous fish ladders. Some Columbia River salmon spawned in the lower tributaries, but most went far up the river, where the huge Grand Coulee Dam now blocks many traditional spawning grounds. Today, the salmon-farming industry is one of the largest fisheries in aquaculture, but not without raising some concerns among environmentalists. Between 1987 and 1995, salmon consumption in the United States increased 170 percent, many times greater than that of its two other popular rivals, shrimp and catfish. Salmon farming is also big business in Scotland and Norway, where the fjords and bays of the rocky coastline provide excellent waters for netpens and cages. When the weather is stormy in these rough waters, the penned salmon escape, then breed with the native wild salmon. In some Norwegian rivers and streams, farmed salmon nearly wiped out native salmon populations by spreading a parasite unknown among wild fish. Sea lice, another problem spread by farmed fish, may cause a high mortality rate among smolts, as baby salmon are called. As interbreeding creates mongrel salmon, many individual species characteristics disappear, leaving salmon that are less robust and without that special knowledge of when to spawn in a particular river. Much salmon raised in the Northwest are of the Atlantic species, causing concern among fish biologists over potential interbreeding of the two species. Waste is another problem. Uneaten feed and salmon feces gather under cages, affecting water quality beneath. Depending on the tides, as far as 500 feet out to sea can be affected as oxygen- depleting gasses are released, killing sealife and encouraging species that love pollution. This reduces diversity near the salmon cages. In a report for SeaWeb, an environmental organization devoted to preserving resources in the world’s oceans, Michael Weber writes that most species of farmed fish and shellfish eat plants occurring naturally in the ponds, lakes, rivers and bays where they are raised. But salmon are carnivorous fish, which means they eat high on the food chain. It takes about five pounds of fish to produce one pound of fish meal, accounting for half the salmon’s diet. Nearly one-third of the world’s ocean catch is used for fish meal and fish oil. The large mackerel, anchovy and sardine fisheries off the coast of South America provide most of the fish for fish meal. These Pacific fisheries are highly unstable, often experiencing drastic fluctuations. During El Niño, for example, nutrient-rich water supplying food for anchovies was suppressed, causing a collapse of the anchovy fishery. Salmon raised in pens are often stalked by various seabirds and other marine animals, such as sea lions and harbor seals. Farmers may use netting that entangles birds or marine mammals, or high-pitched noise devices to deter seals and sea lions. Unfortunately, these devices also keep away porpoise and other marine life. Aquaculture Can Be Sustainable Because the demand for seafood is expected to continue to rise, the world appears on the brink of a "blue revolution," much like the "green revolution" of the 1960s. Despite all the negatives, there is a positive side to fish farming. Due to the high costs of intensive aquaculture, most farmers are looking for ways to improve methods and lessen the impact on the environment. In Idaho, fish farms along the Snake River were flushing effluent from fish ponds directly into the river until some concerned farmers built settling ponds, allowing the waste water to trap much sediment in the ground. They discovered an added benefit: The ponds also provide wetlands for songbirds, waterfowl and other fish. It’s a positive move that’s spreading as more areas comply with the Clean Water Act. New methods include integrating plants into the ponds, as well as other species such as mussels, which can be grown under salmon cages and feed on the droppings from above. Using large bags to enclose sea-raised salmon is another answer. This system not only prevents escape, but also helps capture waste for collection, rather than dispersing it into the surrounding water. In her Worldwatch report "The Blue Revolution" (April 22, 1998), Ann Plant McGinn discusses ways to make aquaculture more environmentally sound. New breeding techniques are designed to maximize growth and food conversion. Unfortunately, this does little to help the hungry of the world. Alternatives to feeding carnivorous fish must be found if we are to enlarge the world’s food supply. Just as growing numbers of people are turning to vegetarianism to help prevent food depletion, in the future others might follow the same path, opting for plant-eating varieties of seafood such as tilapia, catfish and carp over carnivorous species such as shrimp, salmon or shark. Today many restaurant menus display messages informing patrons that fish served are from a sustainable source. Some committed organizers are pushing for certification for ocean fish, and perhaps this will eventually extend to aquaculture. The World Wildlife Fund is overseeing a Marine Stewardship Council to screen marine catch and certify it was caught in a manner non-injurious to seabirds and marine mammals. The United Nation’s Food and Agriculture Agency has issued guidelines for sustainable aquaculture, but so far there’s no enforcement. Many developing nations have felt the brunt of get-rich-quick aquaculture schemes that have flourished along their coastlines, causing damage to the environment and economy. Governments are clamping down on these fly-by-night operations. Honduras now has a moratorium on shrimp farms, while India has banned shrimp farming in high-tide zones. Norway and Scotland have stopped building netpens for salmon in coastal waters, and Egypt now forbids diverting water for fish farms. Little by little, as people become more aware, aquaculture is becoming more environmentally friendly and less damaging. As the world’s population expands, aquaculture is truly a viable resource for food, but it must be seriously examined. Estimates are that, as land becomes more stressed and more people look for alternatives to a red meat-based diet, seafood demand will escalate sharply in the next century. If we can rein in devious practices some aquaculture industries engage in just to turn a quick buck, we’ll be way ahead of the game. Nano Riley is a Florida-based writer and frequent Organica contributor. "Bill Cole" wrote in message news:z4B6b.379085$Ho3.55750@sccrnsc03... |
#3
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Fish Farming
In this area there is an on going battle between a fish farm and the local
inhabitants of the small cove where it is located. (St. Margaret's Bay) All the same concerns experienced on the West coast are felt here. On the day before we brought the Mirage33 back from Mahone Bay and passed through the area, a diver was killed at the site. Gould 0738 wrote in message ... Environmentalists and the industry agree that the use of animal antibiotics and dioxins in farmed fish pose health concerns, seabeds are damaged by fish cages and farmed fish that escape can harm wild stocks. Glad to see the article at least acknowledge those very real issues. As it is presently carried out, fish farming is an enrivornmental disaster. The fish produced are so full of chemicals, it's a wonder they don't glow in the dark. The poop from 200,000 or more fish caged in a small net pen piles up on the seafloor and kills off all the organisms immediately below and for a radius around the operation. Fish farmers up here often use Atlantic Salmon, not native to the NW. Inevitably, some fish escape. These Atlantic salmon compete with the remaining wild fish for food. Atlantic salmon escaped from pens do not reproduce, so they reduce the number and health of wild fish by competing for food and contribute nothing to replenishing stocks through eventual reproduction. Fish farming is common around here. Most of the major food stores now make sure that salmon offered for sale is prominently labeled "wild" salmon if it isn't farmed. I try to avoid buying aquacultured fish. The majority of our restaurants serve faux fish from farms. |
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