Environment

Farming fish in a tiny percentage of the oceans could feed the world

Farming fish in a tiny percent...
Ocean-farmed fish and seafood could meet global demand using only a tiny fraction of the world's oceans
Ocean-farmed fish and seafood could meet global demand using only a tiny fraction of the world's oceans
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Ocean-farmed fish and seafood could meet global demand using only a tiny fraction of the world's oceans
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Ocean-farmed fish and seafood could meet global demand using only a tiny fraction of the world's oceans

With a growing population, the world is looking more and more to the ocean as a source of food. But wild stocks of fish and other seafoods are being overexploited in many areas. Now, a study from UCLA suggests that if fish farming can be moved offshore, then an area of sea the size of Lake Michigan (0.025 percent of the ocean's surface), could meet the global demand for fish and allow wild stock to recover.

Fish is big business. According to the Food and Agriculture Organization of the United Nations, global per capita fish consumption exceeded 20 kg (44 lb) for the first time in 2016. That works out to exports of 73.8 million tonnes worth US$148 billion. Seafood is a major source of protein in many parts of the globe and nutritionists claim that diets with higher percentages of fish are healthier.

The trouble is, the wild fish stocks are under severe pressure from the growing demand, with 57 percent of the stocks overfished to the point of population decline, and another 30 percent classed as overexploited or recovering.

One way of overcoming this is by fish farming or aquaculture. It's not a new idea. Aquaculture dates back to prehistoric times when the first hunter gatherers hit on the idea of keeping fish in pens rather than eating them right away. Over the centuries, fish and shellfish have been cultivated in flooded rice paddies, specially made ponds, and pens in natural ponds, lakes, and estuaries to provide a reliable source of Friday dinners.

Today, fish farming is also big business, with trout, shrimp, salmon, eels, oysters, molluscs, clams, carp, and many others produced in vast numbers. It's a modern success story, but the potential for growth is limited because fish farming in sheltered bays, estuaries, and streams limits where many farms can be established. Fish farming in shallow waters also makes them susceptible to diseases and parasites, as well as making them a source of pollution from fish droppings.

But the new UCLA study led by Peter Kareiva and Rebecca Gentry, indicates that if aquaculture could be moved into deeper offshore waters or, eventually, into the open sea, then the yields produced would easily dwarf the output of the entire present fishing industry. In addition, it would do so with not only less environmental damage, but would actually help reverse the effects of wild fishing, and would be a great economic and nutritional boon to many developing countries.

The UCLA team looked at aquaculture in very broad terms instead of focusing on specific species, as previous research had. Looking at the world's oceans, they eliminated areas where fish cultivation was impractical, such as shipping lanes, marine sanctuaries, off-shore drilling and mining areas, and areas marked by pollution and other environmental hazards. They then studied the physiology of 180 species of finned fishes and bivalves that are farmed, noting what environments they thrived in based on ocean depth, temperature, and their biological needs.

They then eliminated areas in the deep ocean far from the continental shelves. Though these areas might one day be used for aquaculture, the scientists rejected them because current technology and the need for large infrastructure to build, maintain, and service such farms would make them impractical at present.

What they found was surprising. Areas like North America and Europe, which have the capital and technology to exploit ocean-based aquaculture, didn't come out well because heavy environmental regulations make establishing such farms an arduous and expensive process. Meanwhile, other areas were deemed unsuitable because such regulations were too lax, resulting in coastal pollution.

But tropical countries showed the highest production potential, with Guinea in Africa, Bangladesh in Asia, and Uruguay in South America ranking the highest – all areas marked by food insecurity issues. According to the study, nations like Argentina, Indonesia, and India not only have burgeoning populations and poverty issues, they also have fertile seas that could not only feed their people, but provide welcome export dollars.

Along with these benefits, the UCLA team contends that ocean aquaculture would be able to feed the world while improving the lot of wild fish stocks. Because fish farming offshore will be expensive at first, conventional fishing will still be a major player, but farmed seafood would remove most of the pressure to fish vulnerable stocks and allow overfished areas to recover properly as well as making it feasible to place more areas of the ocean off limits from exploitation.

"We need to find more protein for our growing population, and we have pretty much tapped out wild fish as protein sources," says Kareiva. "This study shows that farming fish in the ocean could play a huge role in feeding people without degrading our ocean or overfishing wild species."

The study was published in Nature (PDF).

Source: UCLA

17 comments
jerryd
The only fish farming viable is vegetarian fish fed on algae, etc clean food or grow them to feed other fish. The slop they feed farmed fish is terrible, wasteful mostly fish wild fish eat and gets far worse from there of anything they can find. Not a chance I'd ever eat Asian farmed fish, shrimp as their feed, conditions are not healthy. But I don't understand we already have the largest, lowest cost to maintain and free fish farms now, the Ocean, rivers, streams, lakes. To make them productive beyond anyone's dreams, is just stop screwing them up!! Tampa Bay and from fresh to salt water everywhere here in Florida, fishing is great because we let it heal and stopped pumping pollution, etc into and to it. Offshore it needs some help like more reserves and allow limited large grouper fishing again as the suckers got too plentiful and eating everything now.
watersworm
Just ask "deep ecologists" about this. I'am sure they'll love it !
Loving It All
Fron the article: "Areas like North America and Europe, which have the capital and technology to exploit ocean-based aquaculture, didn't come out well because heavy environmental regulations make establishing such farms an arduous and expensive process. Meanwhile, other areas were deemed unsuitable because such regulations were too lax, resulting in coastal pollution." This strongly suggests that the practices being recommended have major negative environmental impact. If there were environmentally benign why would there be a clash with existing environmental regulations? And, it's clear that without a degreee of such regulations, the practices would run harmfully out of control, hence the "resulting coastal pollution." So, how about a discussion of how to farm in an environmentally benign fashion? This is the same challenge we face with terrestrial agriculture, and it's insane not to consider how to live sustainably. The only other choicea are to poison ourselves or our children, or to poison others and their children.
Kpar
Expansion of free enterprise into these areas will cause a bloom in economic activity and allow those poor countries to become food exporters, and consequently, much less poor.
The world needs this- we are outstripping the natural oceans' ability to regenerate. Win, win!
Douglas Bennett Rogers
This could be the first cash crop for a pelagic nation.
CharlieSeattle
Ocean Fish Farms? Uhh, sorry but Japan is busy nuking all the worlds oceans now!
Japan Declares Crisis As Fukushima Reactor Begins Falling Into Ocean And Radiation Levels Soar
youtube. com/watch?v=-j3Mu3Lcqpc
Published on Feb 5, 2017 Unimaginable Disaster: Japan Declares Crisis As Fukushima Reactor Begins Falling Into The Pacific Ocean And Radiation Soars To The Highest Levels Ever Seen.
The latest developments at Japan's Fukushima reactor have been described as "unimaginable"and "unprecedented". Officials state that damages at the reactor are "far worse than previously thought". Melted fuel has come in contact with underground water and the melted core appears spread over an "extensive area". .....................
Fukushima Is Still Melting Down... youtube. com/watch?v=aRbVHGwkYLE .....................
youtube. com/watch?v=psb9nPu2xV8 Radiation levels at the Fukushima reactor have also soared to their highest levels since the 2011 disaster. The radiation levels inside the containment vessel of the number 2 reactor at the crippled Fukushima Daiichi nuclear complex stood at 530 sieverts per hour, the highest since the 2011 disaster, the plant operator said on Thursday. Previously the highest radiation level monitored in the interior of the reactor had been 73 sieverts per hour.
The new radiation level, has been described by some experts as “unimaginable,”. These are record high fatal radiation levels, according to the institute.
Another truly unsettling revelation about the Fukushima problem came as a boss revealed 600 tons of fuel melted, and they can’t find it. “Uncontrollable fission” is continuing under the site.
Grunchy
There's a practical aspect to deep sea fish farming, namely that the sea gets pretty wild. So how is the farm net to survive? Also how are the fish inside to survive when the sea is crashing around them and they cannot escape? I mention this because the article photo doesn't resemble the sea very often.
Bob
Any time you concentrate live stock, you get disease. Then you need antibiotics. Then to preserve profit, the sick fish must be harvested before they die. The oceans around the poor and unregulated countries are basically full of sewage and chemical pollution. Even the rivers in the U.S. are full of runoff chemicals and more sewage than the public realizes. Most cities release raw sewage every time it rains. The fish will be fed the lowest quality feed and drugs to make them grow faster. Fish farming sounds like a good idea but profit will create an inferior product. Several attempts have been made to harvest plentiful nuisance Asian carp from U.S. rivers for animal feed but so far it has failed. Lake Michigan salmon are full of PCBs other species are contaminated with mercury.
icykel
Wonderful, the future food supply sorted for the new Martian settlements.
Nelson Hyde Chick
Instead of finding ways to feed an ever expanding humanity we should be looking into shrinking mankind. By the time humanity hits nine to ten billion the Earth will just be one huge shithole.