One of the hottest ongoing debates in the world of nutrition is whether fish farming is a viable alternative to commercial fishing. Much like the issue of global warming, relevant and unbiased information is hard to come by. Most websites lean toward one side or another, and neither seems to provide solid evidence proving their stance is better. To find an answer, we need to rely on pure science and research from reputable sources. None of the sources I used for this research received any funding from the government or any entities with a vested interest in the outcome.
It’s no secret that overfishing is a significant problem. Certain species, such as Yellowfin and some subspecies of Bluefin Tuna, have been depleted to the point of being threatened or endangered. Yet, nothing has been done to realistically limit commercial fishing for these species. A report issued by the PEW Environmental Group (view report) states that, even though commercial tuna catches are regulated, the total amount of tuna sold commercially exceeds 141% of the allowable limit. How do we interpret this? Either some fish are being sold multiple times (which is unlikely), or the quotas are not being enforced (which is more likely). Many scientists estimate that at the current harvest rates, all species of tuna could collapse within five years (Global population trajectories of tunas and their relatives – PNAS 2011 108 (51) 20650-20655; National Academy of Sciences), effectively becoming commercially extinct. Newfoundland’s cod fishing industry suffered a complete collapse in 1998 and has never recovered. Stocks of salmon are now less than 30% of what they were just 10 years ago on both the east and west coasts of the U.S. (Rebuilding Global Fisheries, Dr. Boris Worm, et al. Science 31 July 2009: Vol. 325 no. 5940 pp. 578-585 DOI: 10.1126/science.1173146). And we all know what happened to whales. Although whaling has been outlawed, a few renegade countries (mainly Japan, Iceland, and Norway), along with some Native American and other aboriginal peoples, will kill over 7,400 whales this year (Report of the International Whaling Commission 2011, Chapter 5).
Clearly, something needs to be done before it is too late. But what can be done? Realistically, there are only two ways to address the problem: we either need to decrease the demand for fish, or increase the available supply. As the figures show, regulation has done little to help the situation. The problem with regulations is that they are only as good as the ability to enforce them. There is no global “police force” with jurisdiction everywhere, and countries like Japan and Norway have demonstrated that some will not honor the “honor system.” Even countries that want to regulate fishing can only enforce rules within their territorial waters, typically up to 200 miles from shore (less in some areas). International treaties would be required, but they are difficult to negotiate and even harder to enforce. It is unrealistic to think that the worldwide fishing industry will voluntarily slow down or shut down as long as it remains profitable.
Thus, the other solution may be to increase fish stocks. Obviously, this will not happen in the wild as long as commercial fishing continues unchecked. The alternative is to commercially raise fish on fish farms. Fish farming (also known as aquaculture) is actually an ancient practice, dating back as far as 6,000 BC. China began commercially raising carp around 2500 AD, and the Romans raised fish in ponds, similar to modern catfish farms. So, it’s not a new idea. The only difference today is the species we are trying to farm. Non-migratory fish like carp, catfish, and tilapia are easy to raise. China developed methods to raise eels thousands of years ago, and many cultures have been raising shrimp, lobsters, crabs, and shellfish for a long time. All these species need is clean water and food to thrive. Pelagic and wide-ranging species like salmon and tuna are more problematic. They need to be penned in the ocean, a harsh environment, and are more susceptible to diseases and parasites, especially sea lice. However, just like any new technology, the issues are being worked out.
Some of the Objections to Fish Farming Are:
- Farmed fish may escape and damage the ecosystem – This concern arises from confusion between farmed fish (which are just wild fish or their progeny penned in) and GMO (genetically modified organism) fish, which are both farmed and released into the wild through stocking programs. As a rule, GMO fish don’t fare well in the wild, except for a few hybrids like Tiger Trout (a cross between Rainbow and Brown Trout) and some bass hybrids. For instance, albino trout, which are genetically engineered to be white for anglers, rarely survive one season in streams; they are sterile, and their flesh is soft and tasteless. Most GMO fish are sterile females, meaning they cannot reproduce. Genetic engineering has been more successful with plants than animals. To date, no species has become extinct or even threatened due to GMO animals. In fact, all livestock is genetically modified—just not in a lab.
- Fish farms damage the environment – This is a legitimate concern, and some unscrupulous farms have been guilty of damaging ecosystems, much like some land farmers and ranchers. However, this issue can be addressed through regulation and enforcement. Fish farming is a relatively new industry, and it may take a few years for legislation to catch up, much like it did with computers, the internet, in vitro fertilization, and many other topics. The fact is, there are environmentally friendly ways to operate fish farms, and most are doing so effectively. Good closed fish farms filter their water before returning it to the stream, pond, or ocean, and avoid overcrowding fish. Open-water farms use proven methods to limit their environmental impact. Poorly managed fish farms damage the environment, move on, and start over elsewhere. Even in these cases, ecosystems can recover over time.
- Fish farms increase the spread of diseases like sea lice – This concern is overrated. Sea lice mostly affect juvenile fish, which rarely stay around fish farms. Juvenile fish are migrating back to the ocean, and while they may encounter sea lice from farmed fish, studies show that the mortality rate is not much higher than the natural mortality rate of fish in the wild. Most antibiotics have been replaced by vaccines in farmed fish, which are much safer and more effective. Additionally, many fish pens now use copper-alloy wire, which is naturally antibiotic, corrosion-resistant, and safer for both the fish and the environment.
- Farmed fish are not as nutritious as wild fish – This claim is pure nonsense. Farmed fish are nutritionally identical to wild fish of the same species and from the same water. Farmed fish may have slightly higher fat content (because they don’t need to escape predators), but still, their fat levels are far lower than those in extra-lean beef, chicken, or pork. GMO fish may be somewhat different, but they are rarely farmed because they are delicate, especially when young. The new strain of Atlantic salmon (called AquaAdvantage Salmon) has been exhaustively studied and is considered perfectly safe to eat by the FDA and most other regulatory bodies. No deaths or major health problems have been recorded from consuming farmed or GMO fish anywhere in the world. The “Frankenfish” myth is just that—a myth.
You can’t get something for nothing. If you notice, many of the people who complain about declining fish populations are also the ones who gripe about fish farms and GMOs. A study often quoted by detractors (Science 9 January 2004: Vol. 303 no. 5655 pp. 226-229, DOI: 10.1126/science.109144- Global Assessment of Organic Contaminants in Farmed Salmon – Ronald A. Hites, et al.) purports to show that farmed salmon have higher levels of PCBs and other contaminants. However, the FDA and other agencies found that the levels were still far below safety thresholds, and the EPA guidelines are issued for all salmon, not just farmed ones. They also ignore the fact that wild fish contain very high levels of mercury and other contaminants, and commercial fishing destroys ecosystems. Nets often tear up fragile reef systems, ship engines pollute the water, and thousands of other species—including whales and dolphins—are harmed as bycatch.
Private industry has risen to the challenge of dwindling fish supplies, and they are doing a very good job. Currently, nearly 50% of all fish and seafood sold in stores is farm-raised. This means that more wild fish may survive to breed another year. So, go ahead and enjoy a nice farm-raised salmon steak—it won’t hurt you, and the world’s ocean ecosystems will be better for it.
