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Fish farming – the pros & cons

Fish farming – the pros & cons

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In the UK today, a huge amount of the animal and seafood products we consume are farmed. It’s worth remembering that farming of anything is not exactly natural. It’s what we’ve done in order to organise our food production and produce it in volumes and formats that work with the way we now purchase and consume our food. This feature explains how farming is applied to fish, and explores the positives and negatives of this practice.

Why does it happen?

In some parts of the world, wild food is still the primary source. However, in the developed world this is becoming less and less common. Often some wild berries, mushrooms, or perhaps rabbit or venison might be the only ‘wild’ foods we expect to see on a menu. We accept the fact that our beef, chicken, pork, dairy, fruit, veg, cereals and more all come from farmed sources. Our seafood, however, usually comes from a mix of both wild and farmed sources.

As the global population increases, so does the demand for tasty, nutritious and affordable protein. We are all familiar with the terms ‘overfishing’, ‘endangered’ and ‘unsustainable’ being used to describe the state of our oceans. And it is true that over the years, many of our oceans have been abused, which has led to a decline in the wild populations of some species.

To help tackle overfishing, there are now numerous schemes in place to help consumers choose wild fish from sustainable sources. The best known of these is the Marine Stewardship Council, or MSC. However, despite the successes of these schemes, pressure on our oceans and wild fish stocks continues to be an issue, in part due to our dependence on our favourite wild fish: cod, haddock and tuna.

In recent decades, another type of seafood production has seen a steady incline – farming, otherwise known as aquaculture. The farming of seafood products is nothing new, but it is going through a period of enormous growth, and developments in the methods and technology used is having a huge impact on its sustainability.

How much of our fish is farmed?

The most common farmed seafood we consume includes salmon, trout, sea bass, bream, pangasius (often labelled basa or river cobbler) and prawns. Today, in the developed world, it is thought that around half of all the fish we consume is from farmed sources. Certainly, in a UK supermarket or on a restaurant menu, the vast majority of salmon will be farmed. Wild salmon is much less accessible and comes with a substantial price premium.

What does farming fish involve?

In the main, the process is as follows:

  1. Parent fish stock are selectively bred, to produce the fish best suited for farming.
  2. Fish eggs are hatched in small tanks. When they’re big enough, they’re moved to larger tanks where they are fed and monitored.
  3. When they are around 150g in weight, they are moved either to large ponds, or netted areas in the sea, such as the one pictured above.
  4. From here, they are fed concentrated fish feed, until they reach the desired weight. During this time, their health is closely monitored, often using underwater cameras.
  5. Once they reach the desired weight, they are transferred to processing factories where they are killed, gutted and packed.

Is all fish farmed the same?

As with all farming, no two farms are ever the same. Every farm will vary in its standard of animal welfare, environmental impact and sustainability. We are well used to seeing choice when buying products such as eggs, chicken and pork; with options such as Red Tractor, RSPCA Approved, free-range and organic all being available. However, this level of choice is not yet present in farmed fish in the same way.

Despite the lack of obvious choice when buying farmed fish such as salmon, there are many schemes behind the scenes that are tackling the various issues. These include:

  • RSPCA Assured – Focused primarily on the welfare of the fish
  • GlobalG.A.P. – Focused on food safety, ethics and traceability
  • Best Aquaculture Practices and Aquaculture Stewardship Council – All-round programmes aiming to improve environmental impact, sustainability and food safety
  • Soil Association / Organic – Focused largely on environmental impact and organic farming principles

Many UK retailers are adopting one or more of these schemes as a method of tackling the issues around responsible production systems.

How sustainable is it?

The farming of salmon on a large scale is a relatively new industry, which has boomed in the past few decades. This sudden boom has perhaps outrun the ability to fully understand its impact on the environment, sustainability and human health.

In previous years, the industry made many mistakes which caused damage to its reputation. These included the escaping of fish, which caused problems when they then bred with wild populations, the polluting of seas and waterways, use of unsustainable fish feed, overuse of drugs to treat health issues in stocks, and the questionable use of chemicals.

Whilst the industry as a whole is still not perfect, it has learnt from the mistakes of the past and gone through enormous change. Technology has played a huge part in improving sustainability, by enabling farmers to monitor fish behaviour, capture data on environmental impact and use robotics to ensure feeding levels and oxygen levels in the water are optimal.

Further work is still needed to better manage impact on the wild fish stocks in surrounding areas, as this is frequently one of the hidden impacts of this production. It is commonly thought that “inland” ponds can offer more sustainable environments for fish to be produced.

One of the key factors affecting the sustainability of farmed fish is the feed that’s used. Fish such as salmon naturally feed on smaller fish. Therefore, a large percentage of the feed given to farmed salmon is made up of fish protein and fish oil. These fish components will come from wild fish, so this needs to be from sustainable sources to ensure the farmed salmon is, in turn, sustainable itself. As technology and science continue to develop, the ratio of marine ingredients in salmon feed is continually being improved, to help the conversion of wild fish into farmed fish become more efficient. The fact remains that we have a much larger demand for salmon than we do for the small wild fish that go into its feed.

So what should I buy?

The key to a responsible diet is always to eat a wide variety of foods, from responsible sources. We would always recommend varying the fish and seafood you consume, not always demanding the same species.

When buying a farmed fish product such as salmon, trout or prawns, it is recommended to buy from a trusted supplier and ask whether it is from a certified source. Some supermarkets have a policy of ensuring all their salmon carries a certification, such as RSPCA Approved.

At Jamie Oliver, for our restaurants and our products, we always buy from sources that we’ve either assessed ourselves, or that are certified through one of our recognised schemes.

Wild vs. Farmed Fish — Pros and Cons

A Tale of Two Fishes
If you are one of the many people who has been trying to eat better by cutting out red meat and including more fish, you have had to make the decision between purchasing wild vs. farmed fish. It can be a hard decision because there are pros and cons to both.

If you have a fish at your home, you might have nitices that wild caught betta and farm bred betta are different. Especially when it comes to feeding habits, click here and eat What do betta fish eat in the wild and the farm. The only real difference between the two is where they are raised. Wild fish is exactly that, fish caught in the wild. Farmed fish are raised in pens submerged in ponds, lakes or saltwater. Pretty straightforward.

Public perception would tell you that wild-caught fish is better for you because it is caught in its natural environment, the way we have always caught fish. This may or may not be the case, as I will explain.

The stigma attached to farm-raised fish suggests that it is a genetically modified Frankenfish. It is not. It is the same animal you have always eaten that has been raised in a controlled environment.

In an effort to try to demystify your fish shopping experience, we have compiled a list of pros and cons to help make your decision easier.

Wild Caught
The biggest proponent of buying wild-caught fish is that it doesn’t contain any antibiotics or pesticides, though the later really depends on the waters that are being fished. Buying wild caught is no guarantee that mercury or other toxin levels in your fish will be low, again, it all depends on the environment they are swimming in.

Wild fish tends to be a bit higher in Omega-3 acids because wild caught fish eat a diet that lends itself to higher Omega-3 concentration (i.e. other fish). However, the fish farming industry has found ways to introduce more good Omegas into the farmed fish diet by cultivating algae and worms for food.

Without question, the biggest con to eating wild caught fish is the carbon footprint and sustainability. Fish caught in the wild have falling populations and/or are swimming further out to sea. This means the fishing boats are going farther and farther, burning more and more fuel, to make the round trip.

On top of that, the demand for fish is so much higher that many of their natural habitats are being over-fished or have been wiped out completely. The World Bank estimates that by 2030, two-thirds of all of the seafood will be farm-raised due to over-fishing and increasing demand.Depending on your personal preference, this next point could be a pro or a con. Similar to

Depending on your personal preference, this next point could be a pro or a con. Similar to wild game vs. domestic game, wild caught fish tends to be leaner than farmed fish as their diets don’t contain as much fat. The flavor difference seems minimal.

By far, the best argument for eating farmed fish is its reduced impact on the environment—though it does still have some. Consider sending fishing boats further out to sea and back in, and putting the fish on trucks to get them to market, the carbon footprint of farm raised fish is significantly less.

Also, farming fish helps prevent (or at the very least slow) over-fishing of their natural habitats. And farming actually helps to rebuild the wild population by allowing it to be.Farmed fish means that we are able to keep up the demand for seafood. It is estimated that 50% of all seafood consumed is farmed, and that percentage is expected to rise. By farming, we don’t deplete all of our natural resources.

Farmed fish means that we are able to keep up the demand for seafood. It is estimated that 50% of all seafood consumed is farmed, and that percentage is expected to rise. By farming, we don’t deplete all of our natural resources.

Not all farmed fish are the same. Farm-raised fishing practices and regulations differ from country to country. Pay attention to the country of origin when buying your farmed fish. All retailers are required to label the country of origin for all seafood for just this reason.

Most farm-raised salmon are fed a diet that contains ground up fish which doesn’t help the overfishing and sustainability problem, it actually makes it worse. And shrimp farming has been thought to be responsible for more than half of all of the mangrove loss in the world and almost all of the shrimp sold is farmed. Also, fish can be raised in cramped conditions similar to industrial-farmed livestock which can lead to less healthy fish.

The biggest takeaway you should get from this is while both options have their pros and cons, you shouldn’t stop eating one or the other. Just be smart about your choices. And, no matter how it’s raised, eating some fish is better for you than eating no fish.

And, here is a reference card to print out and keep in your wallet for on the go decisions when you are in the market or a restaurant.

Pros and cons of farmed salmon

Just what this may mean for human health is murky, given that the risk appears to be small and that the health benefits of eating salmon, whether farm-raised or caught in the wild, are thought to be considerable.

But the message to fish farmers was unmistakably clear: Stop feeding your penned-up salmon the fish meal that seems to be causing the problem.

The bad tidings about farmed salmon came via a scientific report published recently in the journal Science. The researchers sampled 700 salmon from around the world and found that concentrations of organochlorine chemicals were far higher in farmed salmon than in salmon caught in the wild.

They also found marked geographical differences farmed salmon from Europe was more contaminated than farmed salmon from North or South America. These differences can be traced to feeding the salmon ground-up smaller fish that have themselves been contaminated with toxic chemicals from polluted ocean waters.

Focusing on polychlorinated biphenyls, or PCB's, the researchers suggested that consumers should probably limit themselves to one meal of farmed salmon per month.

They reached that conclusion by applying a formula developed by the U.S. Environmental Protection Agency to estimate the cumulative impact of ingesting several chemicals at once. But this looks like a case where risk estimation has outrun common sense.

The one-meal-a-month advice seems at odds with the standard recommendation from heart experts that people should eat two fish meals a week, preferably fatty fish like salmon, tuna or mackerel, to help combat cardiovascular disease.

What's more, the contamination levels found in the new study were well below the tolerance levels for some individual pollutants set by the U.S. Food and Drug Administration and must be viewed against the background of a huge drop in recent decades in the amount of PCB's, dioxins and similar chemicals found in the food supply.

Cooking the salmon and trimming off its skin would reduce the contaminant levels significantly.

Those who worry about toxic chemicals, especially pregnant women, may want to pay extra for wild salmon or limit their consumption of farmed salmon, always aware that many other foods contain these same contaminants as well. But those who are more concerned about healthy hearts will see no reason to give up this tasty source of nutrition.

The real message of this study is that the fish farming industry needs to clean up its feeding materials to reduce the level of contaminants.

It would also be desirable for salmon to be labeled clearly to show whether it was farmed or wild, and where it came from. That would help consumers make wise choices and put pressure on the dirtier parts of the fish farming industry to clean up.

Advantages and disadvantages of biofloc

The pros of biofloc

The flocs themselves are protein-rich and provide fish and shrimp with a good source of vitamins and phosphorous. The authors explain that allowing the microbial flocs to proliferate can improve water quality and immobilise toxic nitrogen. Farmers have also reported greater productivity indicators with the system when compared to conventional aquaculture techniques. Biofloc production can decrease mortality rates, increase larval growth and improve growth rates in the cultured species.

The other key advantage of biofloc technology lies in its improved water and land use rates. Since the system relies on a limited (or near zero) water exchange, the overall environmental impact of production is low. The reduced water inputs decrease pollution and allow for greater biosecurity during production.

The cons of the system

There’s more to biofloc than meets the eye. The system requires a startup period and yields aren’t always consistent between seasons. Since producers must constantly mix and aerate culture water, energy costs could be higher than expected.

In addition to these factors, producers must actively manage biofloc ponds to prevent nitrite accumulation and to keep alkalinity levels remaining within a healthy range. Monitoring fish health and welfare is also key – bioflocs can increase the levels of suspended solids in the water, leaving fish and shrimp susceptible to environmental stress.

Though some evidence suggests that the microbial flocs have a probiotic effect on the culture environment and can regulate vibrio activity, this hasn’t been observed in all studies. The researchers note that in some trials, microbial flocs have contained elevated vibrio counts, leaving fish at risk of disease. As it stands now, researchers don’t have a full picture of how individual microbial flocs operate or how to make them proliferate in a predictable way – leaving producers at a disadvantage.

Cons Of Aquaculture & Fish Farming

There can be practical problems with pond based aquaculture

There can be some practical problems with pond based aquaculture such as deep green pond water, muddy pond water, a red layer on the pond water, oxygen depletion in water, excess ammonia, production of hydrogen sulphide, black mud at the bottom of a pond, large aquatic plants in ponds (

Good management may not prevent technical difficulties with aquaculture

… even under good management, several technical difficulties may arise during fish culture with a possibility of large scale loss of production (

Some farmed fish need wild fish as feed, and it can be resource inefficient when considering feed to production conversion

… [some farmed fish species, and] particularly more recently domesticated species like salmon, require wild fish rendered as fish meal and fish oil for their food. What this means is that most of the time, it takes more than a kilogram of wild fish to create a kilogram of farmed fish

… [one report indicated that the] feed-to-edible product ratio … could be more than 3 kilograms of forage fish to produce 1 kilogram of edible farmed fish

[Although, it should be noted that fish farming has become more feed conversion efficient in recent times]

[Of all the farmed organisms, fish might have the best feed conversion efficiency for several reasons to do with requiring less energy -] One of the appeals of aquaculture, both as a profitable business, and as a subsistence provider of protein for human populations, is in the efficient growth of fish … [and several key factors lead] to energy savings, which provides more available energy for growth, resulting in the highest feed conversion efficiency of widely domesticated animals

Farming carnivorous fish, such as salmon, does not always reduce pressure on wild fisheries

Carnivorous farmed fish are usually fed fishmeal and fish oil extracted from wild forage fish.

The resource footprint of aquaculture can vary

The typical resources required for aquaculture might involve feed (which carries it’s own footprint), water, power used on site, and processing and storage energy used (

Energy can come from fossil fuels like coal (

There’s also effluent and waste management to consider from the farming process

Fish farming can use forage fish species, which can undermine marine food webs and have a secondary impact on other fish species in the wild

… the exploitation of the world’s forage fish is undermining marine food webs. Some 20 percent of the world catch is now forage fish, the vast majority of which is used for aquaculture feed (

[ has a good graphic where they show how top predator, intermediate predator, first order consumer and primary producer fish species all relate, and what impact consumers are really having when they eat a fish farmed with wild fish feed]

There’s potential waste and waste pollution to consider with fish farming

[Waste comes in the form of] fecal matter and unused feed [and] These largely nitrogen-based wastes can cause oxygen depletion in coastal environments and a net loss of marine productivity in certain coastal areas

Additionally, the use of antibiotics, antifoulants, and pesticides [can all cause waste pollution in the external environment]

In the past, when the aquaculture industry was just getting its footing, certain factors inhibited the industry from producing fish sustainably [and] environmental problems did arise [such as] nutrient and effluent build-ups, the impact of fish farms on local wild fisheries with respect to disease and escaping, and environmental degradation due to the site’s location

Can result in disease, abandonment habitat destruction

[One example of this is when shrimp have been farmed in near coastal mangrove forests in the past. After disease set in, the ponds were abandoned, and the result was the destruction of] hundreds of thousands of acres of mangrove forests – ecosystems critical to the production of wild fish and the protection of the coast from storm surges (

Disease transfer from farmed fish to wild fish is a potential problem

The farming of species in wild environments can be a vector for disease proliferation in the wild environment. Disease transfer in salmon aquaculture is perhaps the most reported instance of this phenomenon (

Farmed fish escaping into the wild environment might be problematic

[The two issues with farmed fish escaping into both the ocean and land based fresh water sources, and that there’s risk the farmed fish dilute] wild populations’ genetics [and there’s also the chance that farmed fish with high reproduction rates take over a wild environment]

There can be a conflict of interest between production at scale, meeting demand, running at profit and the comfort of the fish

What Are The Pros And Cons Of Farmed Fish?

Imagine you are at the grocery store and are trying to decide if you should buy the wild fish or if the farmed fish. To decide you need to learn The Pros And Cons Of Farmed Fish. Keep reading to answer your question, and educate yourself.

Wild vs Farmed Explained

Wild fish are exactly what they sounds like, fish that live in the wild and are caught by fisherman. Farming fish on the other hand can take place in a variety of ways. Farmed fish can be held in ocean pens, as well as in inland ponds, lakes and tanks. Wild or farmed, both allow fish to be raised and harvested responsibly, if well cared for.

Today, farmed fish currently provide about one-third to one-half of the world’s seafood supply. This includes fish as well as shellfish. This number is still on the rise, and it allows producers to keep up with the demand for seafood.

Some types of fish are primarily farmed, whereas others are still fished from the wild in addition to farming. However, because demand is ever increasing for fish, farming is on the rise to keep up. Trout, tuna and salmon are often caught wild as well as farmed, in order to maintain a supply that meets the demand. Other types of fish such as tilapia and catfish are mostly farm raised. Below is a list of fish that are primarily farmed today.

Farmed Fish


Mahi mahi
Sea Bass
Steelhead Trout
Yellowtail (amberjack, himachi)

Pros of Farming Fish

There are many benefits to farming fish. Farmed fish in general, tend to grow faster than wild fish. They also have a richer taste, and tend to be more tender when eaten. Another pro of farming fish is that, farmed fish can be harvested without the stress and damage that is caused when wild fish are harvested with a hook or net. Farmed fish are processed earlier and therefore more fresh, because they are cleaned closer to when they were caught. Also, farming fish allows the ecosystems to not be thrown off balance by overfishing the wild populations.

Cons of Farming Fish

While farming fish can be a better option, not all fish farmers handle it responsibly. There have been occurrences where contamination was spread from farmed fish in ocean pens. Salmon and tuna are often farmed in ocean pens and nearby water can sometimes become contaminated with waste products, food and antibiotics from the farmed fish. Fish meal that is fed to salmon and tuna, whether raised in the ocean or not, has been discovered to sometimes increase the levels of environmental toxins, specifically dioxins, such as PCB (polychlorinated biphenyl), in the flesh of farmed fish. Other fish, such as tilapia and catfish feed off vegetarian pellets, and don’t encounter dioxin problems.

While there are both positives and negatives to farming fish, if it is done responsibly it could actually be a good thing. Fish consumption is known to be a healthy meat alternative. Because of this, the demand for all types of fish is ever increasing. In order to keep up with the demand, farmed fish is a necessity and avoid overfishing the wild population.

Perhaps you have wondered What Are The Pros And Cons Of Farmed Fish? While there are many benefits, there are also negatives associated with farmed fish if the fish are not cared for responsibly. If cared for responsibly, farmed fish can be a great way to keep up with the ever increasing demand for various types of fish.

What is your favorite kind of fish?

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Hyper-drive: the pros and cons of intensive RAS production in the US

The hyper-intensive production of tropical species might be a hard sell in the US, but a handful of companies have developed systems that have made successful leaps in the sector.

Over the past 20 years there have been several well-funded attempts at hyper-intensive commercial shrimp farming in the US. Two of these established “high tech” farms were destroyed by hurricanes during the years 2017 and 2018 and one was reported to be unable to recover. A third established intensive shrimp farm that had obtained over $20 million in funding is now defunct, apparently due to an inability to continually produce shrimp for market at an economically sustainable level.

However, there are three examples of successful hyper-intensive commercial aquaculture operations in the US that we can use for important comparisons. Blue Ridge Aquaculture of Virginia grows tilapia hyper-intensively. The farm is located outside of the influence of hurricanes and has been economically viable for over 25 years. The Fish Site has previously reported on this company, who told us that total vertical integration and firm biosecurity are the keys to their success. Blue Ridge currently grows 4 million pounds of tilapia per year and ships them live to market in big cities. This is one way that an intensively farmed US aquaculture product can successfully compete with cheap Asian seafood imports, which currently dominate the US market.

Another important example comes from a US producer of shrimp that uses zero water exchange recirculation technology, which has operated for the past six years. The company, American Mariculture – which operates under the Sun Shrimp brand – is located on Pine Island off the coast of Florida and produces 327 tons of 25g shrimp per year. The shrimp are sold fresh, never frozen, from their website they are then distributed throughout the US directly to restaurants using overnight UPS shipping.

Florida Organic Aquaculture produced vannamei shrimp in biofloc raceways

Although Sun Shrimp grows shrimp to a size just outside the commodity range, they have been successful in competing with cheaper imports. According to Robin Pearl who is the president of the company, “Marketing the shrimp has not been a problem—even at $13 a pound.” This is another way an intensive aquaculture production system employing tanks could be economically viable in the US: selling directly to retailers and restaurants is an impressive strategy considering these shrimp are sold at over three times the price of cheaper frozen imports.

A more recent success story comes courtesy of an integrated organic salmon and lettuce producer in Wisconsin. The company, Superior Fresh, just like American Mariculture, ships directly to market. Aquaponics is well known for its efficiency and typically generates at least 80 percent of revenue from plant harvests produced from fish waste – as confirmed by chief operations officer Brandon Gottsacker who says (in regard to growing lettuce from the waste produced by salmon which has an FCR of 1:1): “That’s 1lb of input into the system and 10lb of healthy organic food out of the system.” Most importantly, such systems rely on adequate solids removal and perfect control of ion concentrations imperative to growth of vegetation in water. Superior Fresh sells 100,000lb of leafy greens every month. Producing fresh organic produce in an area known for its long, cold winters is another way to successfully compete with cheaper agriculture imports.

It is well known in the shrimp farming sector that industrialised countries such as Australia and the United States have very low output because they cannot compete economically with such industry giants as China by growing a commodity-size shrimp of 15-20g. Growing smaller shrimp allows a faster turnover promoting a high profit potential, higher growth rates and a growing season of two to three months that fits in well with countries like China that experience periodic, challenging dry and wet seasons.

Moreover, subsidies and financial incentives provided by the government of China, as well as a high seafood demand, cheap labour, lack of environmental regulation and lower land costs, have resulted in China’s success in shrimp aquaculture. Therefore modern intensive shrimp companies in the US have attempted to escape the commodity market by growing shrimp greater than 25g. However, growing larger shrimp at a high biomass is more challenging due to longer growing seasons which involve a greater risk of loss of shrimp due to disease, periodic devastating weather events, water-quality issues and slower growth rates.

There are a few published economic analyses of intensive shrimp farming that discuss the important variables and minimum production numbers that are required for success. One of the few complete bio-economic analyses conducted on indoor greenhouse culture of shrimp was developed by Van Wyk et al in 1999 using raceways. After a series of research production trials, a hypothetical model of a commercial farm was developed. Using the actual research data, an internal rate of return (IRR) of 13 percent was calculated using the poor production performance of shrimp growing at a low 60 percent survival, 0.7g per week and a harvest biomass of 2.5kg/m3. The authors of this study suggested that if survival alone could be increased to a moderate rate of 70 percent, then the IRR would increase from an unattractive 13 percent to a viable rate of 26 percent, indicating the economic sensitivity of this variable.

Alternatively, if the low growth rate of 0.7g per week could be slightly increased to 0.85g per week, then the IRR would increase from 13 percent to a healthy 32 percent, exposing another economically sensitive variable. If both survival at 70 percent and growth at 0.85g per week are considered, the IRR of this model jumps to 48 percent, making it a very attractive investment opportunity. However, the analysis considers a premium market price of $5.86 per pound at an 18g size for the year 2001, which is nearly twice what Van Wyk et al. had previously estimated during that period.

Sun Shrimp produces 325 tons of organic shrimp a year

These results were confirmed by a second and much more recent intensive-aquaculture production analysis in 2009 (Hanson et al.). By increasing survival in their economic models by 20 percent, the IRR was increased to 97 percent. Furthermore, a 20 percent increase in stocking densities or growth rate increased the net present value (NVP) by 57 and 45 percent. Contrary to this, a reduction of 20 percent in the cost of feed or post-larvae only reduced the NPV by 22 and 9 percent. On these results, it seems obvious that for an intensive-aquaculture project to be commercially successful, survival and growth rates have to be maximised.

Current attempts at commercial hyper-intensive shrimp production systems in the US have reported regular harvest biomass from 2.2kg/m 3 to 3.5kg/m 3 of shrimp larger than 30g. The production costs reported were $9.35 per kilogram, with a sale price of whole shrimp established at $12.6 per kilogram. Incorporating the fixed costs for the necessary expensive infrastructure associated with hyper intensive shrimp aquaculture would result in little or no profit per kilogram of shrimp produced. Therefore there is a clear need to increase harvest biomass by increasing shrimp survivals and also to develop alternative markets in order to provide economic sustainability for hyper-intensive shrimp production in the US.

In conclusion, hyper-intensive aquaculture operations would be more sustainable if they were located out of the range of devastating seasonal weather events. In addition, the ability to produce products that are outside of the influence of the commodity market, including niche markets, would be imperative for financial success. The most important production variables that have been outlined in published studies indicate that high growth rates and high stocking numbers with good survival numbers would be necessary to achieve the high biomass and efficiency that intensive aquaculture operations in the US require for sustainability.

Fish Farming Pros and Cons

Are you eager to know the fish farming pros and cons? Fish farming plays an important role in the food industry by providing enough supply for local and international demand, however in order to be successful on this business you need to know the pros and cons, let us teach you on how to deal with it.

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Fish farming, or also known as “aquaculture, plays a significant role in supplying the demand of the world’s need for fish and other sea foods such as salmons, tunas, shrimps, crabs, mussels, catfish and aquatic plants like seaweeds.

The industry of fish farming has been exercised by our ancestors hundreds of years already, this is according to experts. It is said that about a quarter of the total consumed fish all over the world came from fish farming or aquaculture. Here you can see how important the industry is in supporting the food industry of the world. However, the fish farming industry faces a very big challenge in the recent years on how it can sustain the demand regardless of the disadvantages it could bring to the natural environment.

Let&rsquos discuss the pros and cons of fish farming so you could have a bright idea on you will manage the business.

The Pros and Cons of Fish Farming and How to Deal with it

Let&rsquos start with the advantages. Fish farming was created as an alternative source of freshwater and saltwater fish products to answer the increasing demand of the world for food due to the explosion of the population. Since the oceans and lakes can&rsquot sustain this demand alone, the fish farming industry replaces this shortage by producing fish supply in much quicker time than its natural habitat. The fish farming industry also has been the answer to save some fish species like red snapper and cod from disappearing in our oceans by bringing them in aquaculture farms to revive their population. Another great advantage of aquaculture is the additional job opportunity it can provide to those areas where unemployment is rampant, particularly in the coastal areas. In addition, fish farming can solve the problem of malnutrition by providing enough supply of fish which is a great source of protein, iodine, omega-3, and other nutrients needed by our body.

On the other hand, if there are pros there are also cons. One great disadvantage of fish farming is regarding environmental concern. Because the fish farms contain a huge number of fish that makes them crowded in their artificial home, some of them will die and can cause pollution to their water sources. And when the water sources had been contaminated, it will produce bacteria to infest the area along with other diseases, hence threatening the health of the wild population causing them to die abruptly. Feeding the fish population in the farm is another issue. The feeds are more on fish meals, meaning some species are eating their kind like shrimps and salmons for example. To sustain the fish farm you need a great resource of these feeds, thus making the business extremely unproductive.

The Pros and Cons of Fish Farming

Update to this article, which was first published on our site in 2008: In November 2015 the U.S. Food and Drug Administration (FDA) approved the sale of genetically modified (GM) salmon to consumers, stating that “food from the fish is safe to eat.” The FDA decision allows a biotechnology firm, AquaBounty, to produce GM salmon in a process it submitted for approval almost 20 years before. According to the FDA, the salmon, called AquAdvantage, “contains an rDNA construct that is composed of the growth hormone gene from Chinook salmon under the control of a promoter (a sequence of DNA that turns on the expression of a gene) from another type of fish called an ocean pout. This allows the salmon to grow to market size faster than non-GE farm-raised Atlantic salmon.” Environmental, consumer, and health advocates have raised the alarm. Among their concerns are that the farmed GM fish could escape the farms and cause unknown consequences for other fish and the marine environment.

— A spokesperson from Friends of the Earth said the FDA approval was “flawed and irresponsible,” and that “it’s clear that there is no place in the US market for genetically engineered salmon.” According to Consumer Reports, 92% of Americans believed that they should be told when they are being sold genetically modified foods, but the U.S. government has repeatedly refused to enact legislation mandating that GM foods be labeled this contrasts with the laws of some 64 other countries around the world, including some of the world’s biggest economies, including China, Russia, and the countries of the European Union.

Fish farming—aquaculture—has been practiced for hundreds of years, from pre-Columbian fish traps in the Amazon basin to carp ponds on ancient Chinese farms.

Today aquaculture produces a wide variety of both freshwater and saltwater fin fish, crustaceans, and mollusks: farmed species include salmon, shrimp, catfish, carp, Arctic char, trout, tilapia, eels, tuna, crabs, crayfish, mussels, oysters, and aquatic plants such as seaweed. Some species spend their entire lives on the farm, while others are captured and raised to maturity there. As the stocks of wild fish began to diminish, and even before the catastrophic decline of such species as cod, sea bass, and red snapper, fish farming was seen as a way to satisfy the world’s growing appetite for healthful fish and at the same time a means of sparing wild fish populations and allowing their numbers to rebound. Today, over 70 percent of world fish stocks are fully exploited or are already overfished.

Aquaculture was also seen as a way to provide a living for thousands of farmers and fishermen who had seen their usual crops lose value and their catches disappear. And it was hoped that fish farming would help provide the protein needs of Third World populations through locally produced products. Fish farms could be located not only along coastal areas but near inland rivers and lakes, wherever water could be supplied. The fish farms’ “fields” could be large tanks and artificial ponds as well as enclosures in natural settings such as rivers, lakes, seacoasts, or the open ocean. Today the $78 billion aquaculture industry supplies nearly 40% of the seafood we eat and is growing faster than any other agricultural sector. China is the world’s leading supplier in 2006 it produced about 115 billion pounds of seafood, which is shipped worldwide but mostly consumed by the Chinese themselves. According to the Environmental Defense Fund, “Global fisheries exports now earn more revenue than any other traded food commodity, including rice, cocoa or coffee.”

Growing concerns

Many of the concerns surrounding fish farming arise from the crowding together of thousands of fish in their artificial environment. Waste products, including feces, uneaten food, and dead fish, are flushed (often untreated) into the surrounding waters where they add to the contamination of the water supply. Also in this effluent are pesticides and veterinary drugs that have been used in an effort to treat the pests and diseases that afflict fish in these concentrated numbers. Such chemicals affect the entire aquatic ecosystem. In many areas, notably China, waters are already heavily polluted from sewage, industry, and agricultural runoff. There are serious questions about the advisability of eating fish raised in such environments. Consumers in the U.S., who had been advised to eat fish several times a week for the health benefits, were dismayed to learn that highly recommended farmed salmon was found to be tainted with mercury and PCB’s.

Fish in captivity must be fed. Some species are herbivores or omnivores species like shrimp and salmon are carnivorous and must be fed on other fish. According to Time magazine, “It takes a lot of input, in the form of other, lesser fish — also known as ‘reduction’ or ‘trash’ fish — to produce the kind of fish we prefer to eat directly. To create 1 kg (2.2 lbs.) of high-protein fishmeal, which is fed to farmed fish (along with fish oil, which also comes from other fish), it takes 4.5 kg (10 lbs.) of smaller pelagic, or open-ocean, fish.” In an article on bluefin tuna farming published in the San Francisco Chronicle, a seafood wholesaler estimated that it takes 26 pounds of feed to produce 1 pound of bluefin tuna the feed consists of squid, blue mackerel, and sand eel. A staggering 37% of all global seafood is now ground into feed, up from 7.7% in 1948, according to recent research from the UBC Fisheries Centre. Some goes to fish farms and some feeds pigs and poultry. Both are examples of what Francis Moore Lappe called “reverse protein factories,” where the resources far outweigh the product.

Environmental impact

Coastal areas worldwide have seen habitat and ecosystem alterations in order to accommodate fish farms. Mangrove forests–complex ecosystems that lined great stretches of the coasts of Thailand, Vietnam, and China, as well as those of other countries—have been destroyed to create shrimp and fish farms (as well as other businesses). These swamps helped buffer the the effects of hurricanes, cyclones, and tsunamis it is believed that the loss of coastal wetlands along the Mississippi Delta contributed to the immense devastation from Hurricane Katrina. Other agricultural areas were also affected. The World Resources Institute estimates that “nearly half the land now used for shrimp ponds in Thailand was formerly used for rice paddies in addition, water diversion for shrimp ponds has lowered groundwater levels noticeably in some coastal areas.”

Pests such as sea lice (tiny crustaceans that prey on fish) proliferate in fish farms and spread out to afflict wild fish. Sea lice are especially damaging to salmon, sometimes eating away the flesh of their heads down to the bone. A fish farm on Loch Ewe on the Western Scottish coast is blamed for damaging Scotland’s wild salmon stocks. Viral, fungal, and bacterial diseases that arise in fish farms have spread to native fish populations. Individual fish, often of non-native species, escape from fish farms to compete with native fish for food and habitat resources.

Agencies worldwide have called for better management of fish farms, strict enforcement of regulations to protect consumers, more research on sustainable practices, and sharing of information on sound aquacultural practices. International, regional, and local agencies are all involved in the effort, as are agencies concerned with animal welfare, the environment, and food resource management. Responsible, sustainable fish farming is an achievable goal and one that will become an increasingly important part of stewardship of the Earth’s water resources.

Images: Feeding fish at a sea-based fish farm in Mahebourg off Mauritius’ southeast coast, January 2007 (Ed Harris—Reuters/Landov) workers bag up dead fish for burial at a fish farm at Nanning in China’s southern Guangxi province (Color China Photo/AP) sea lice on the belly of a sea trout (James Butler/AP).

Farmed Fish Are Not Healthy, Contrary to Popular Belief

The similarities between the “quality” of the animal raised in confined captivity to those raised naturally are eerily similar to factory farmed livestock like cows, pigs, and chickens.

At the end of the day, the companies responsible for raising these animals care about their profit. When the bottom line is involved, many things are done to make business more efficient and more profitable.

The shortcuts that are taken and the practices implemented can cause a lot of harm in the long-term to have quick gains in the short-term.

Farmed Fish Health Risks

There are many reasons that the farmed version of fish is less healthy than wild fish. While farmers may argue the following practices are for the wellbeing of the fish, the reality is they don’t want to hurt their profit margins.


Like animals raised on factory farms, farmed fish are fed high quantities of antibiotics. While it can be argued this is done with good intentions, the reality is more sinister.

The conditions where fish are raised on factory farms are so crowded that if a fish gets sick it is possible to spread the disease to countless other fish.

While it’s nice to think that farmers don’t want fish to get sick, the problem with consuming too many antibiotics is obvious. The fish can become resistant to the antibiotics and can make it more difficult for them to fight off disease.

What’s even scarier is the potential for humans to develop resistance to antibiotics as well. When humans continuously consume that are present in the food they eat, they can develop a resistance that potentially harms them down the road if they need to take a certain antibiotic to fight off illness.

Dr. Danilo Lo Fo Wong, Programme Manager for the Control of Antimicrobial Resistance at the WHO says the “Overuse of antibiotics—in farming or for human medical treatment—speeds up the development of antibiotic resistance, which is when bacteria change and become resistant to the antibiotics used to treat infections they cause. This is compromising our ability to treat infectious diseases and undermining many advances in medicine.”


According to the Environmental Working Group, “seven of ten farmed salmon purchased at grocery stores in Washington DC, San Francisco, and Portland, Oregon were contaminated with polychlorinated biphenyls (PCBs) at levels that raise health concerns.”

PCBs cause cancer in animals are probably human carcinogens, and their production was banned by the United States government in 1978 after discovering just how toxic this chemical actually is.

Many studies show that PCB is highly prevalent in the fishmeal that is fed to farmed fish. The twisted irony? Many of the fish that compose the fishmeal is also grown on fish farms around the world.

Toxic Chemicals in Farmed Fish

Other alarming chemicals that are typically found in farmed fish include dibutyltin, Polybrominated Diphenyl Ether (PBDE), and dioxins

Dibutyltin, which is commonly used in the production of PVC plastic, can increase the risk of prediabetes and obesity if consumed by humans.

PBDE consumption by humans can alter thyroid hormone homeostasis and cause thyroid dysfunction. This can lead to the subsequent development of thyroid cancer.

According to the World Health Organization, the consumption of dioxins can cause reproductive and developmental problems, damage the immune system, interfere with hormones and also cause cancer.

The pros and cons of net cleaning

Net cleaning in certain circumstances can create conditions “not dissimilar to a harmful zooplankton bloom”, according to a leading fish vet.

Chris Matthews, Operations Director at the Fish Vet Group, says that recent trials in Ireland suggest that net cleaning can have harmful effects on gill health – especially if not done sufficiently regularly.

As he explains to Fish Farming Expert: “Over the past few years, gill disorders have emerged as one of the most economically significant disease groups in salmon aquaculture globally. Most farmers recognise the importance of net hygiene to gill health, though the complexity of the relationship deserves more research. Fouled nets will compromise fish welfare by reducing oxygen levels and limiting waste removal, and may be a reservoir for gill disease agents such as Neoparamoeba perurans, the causative agent of amoebic gill disease. Our experience shows that heavily fouled pens with low water exchange experience more severe AGD.”

Despite this, however, he points out that cleaning of heavily fouled nets also has its dangers.

“Many of the fouling organisms, such as hydroids and anemones, are themselves capable of causing gill damage when present in the waste generated during in situ cleaning. These organisms are cnidarians – related to jellyfish and hydrozoans – and contain stinging cells capable of causing gill irritation. Challenge trial work carried out by colleagues in Ireland has shown that shredded fragments of the common fouling organism Ectopleura larynx, such as might occur during high-pressure net cleaning, causes acute gill pathology. Where cleaning farms with heavy fouling, we may be creating conditions not dissimilar to a harmful zooplankton bloom,” he warns.

As a result, he points to the need for regular cleaning of nets and warns that not all sites are suited to in situ high pressure net cleaning.

“In terms of mitigation, farms need to focus on keeping nets as clean as possible. By keeping cleaning intervals short, such as every two weeks, hydroids are unable to complete their life cycle and establish on the nets. Careful consideration of tidal flows when performing in situ cleaning will help prevent fish being exposed to shredded fouling organism material. At some low-motion sites with poor water exchange, in situ cleaning may not be appropriate and nets better removed to land-based facilities for cleaning. Regular monitoring of gill health is vitally important and best done by a combination of visual inspection and histopathology,” he explains.