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The fishy business of factory farming

News Section Icon Published 11/06/2012


Friday marked World Oceans Day ("where people around the planet celebrate and honour the body of water which links us all, for what it provides humans and what it represents" – well said!) so we thought we’d lift the lid on one of the lesser-known areas of factory farming – intensive fish farming.

The rise of aquaculture

We’re arguably not as familiar with intensive fish farming, or "aquaculture", as we are with other factory-farming practices; it’s a relatively recent development and fish are cold-blooded, which has led to a widespread fallacy that they can’t experience suffering. But it’s no small fry – nearly 50% of the fish we eat comes from aquaculture1, with tens of thousands of fish often crammed into the same barren cages or pens.

Fish can feel pain

The common myth that fish can’t suffer needs to be put to rest – we’ve known that fish feel pain since the 1970s, as a result of independent scientific inquiries commissioned by the RSPCA. Subsequent research confirms their findings. And in 2007, Compassion in World Farming showed that factory-farmed fish can suffer from serious problems, including physical injuries, increased susceptibility to disease, high mortality rates and, in some countries, inhumane slaughter methods2. Famed author Jonathan Safran Foer wrote about this issue in The Guardian3 (article now out of copyright) writing: "Factory-farmed chickens, turkeys and cattle all suffer in fundamentally similar ways. So, it turns out, do fish. We tend not to think of fish and land animals in the same way, but aquaculture…is essentially under-water factory farming."

Food wastage

And as with other types of factory farming, animal welfare is just the start of the story. Recent news reports indicate industrial fish farming isn’t such a great solution to the problem of feeding the world’s rapidly growing population.

All too often, we hear claims that fish farming is necessary to take the pressure off wild fish stocks. The reverse can be true however. Intensive fish farms are protein factories in reverse, using two to three tons of wild-caught fish to produce one ton of farmed salmon and trout, for example. The feed species, such as anchovies, sardines and sandeels, are often put under pressure as a result, with consequent damage on the wider natural food chain. And fish farming can also affect wild fish stocks by encouraging the spread of sea-lice (parasitic organisms) infestations – these can potentially wipe out large volumes of fish. Simply put, feeding wild fish to farmed fish puts wild fisheries under pressure.

A threat to our health

Research also shows that farmed salmon, for example, are far more polluted that wild salmon (having been fed wild fish that already carry a high pollutant burden), carrying high levels of pesticides* and a cocktail of other pollutants, which can pose a health risk to us4.

What’s the solution?

All in all, as we race towards a global population of 9 billion, we need to find smarter, safer ways of feeding the world. As with farming in general, there is a spectrum of quality with aquaculture. We can choose, for example, to farm fish such as tilapia, which are more efficient converters of protein and don’t necessarily require a diet including other fish. This reduces the risk to our health, too. The complication is that some systems are more sustainable in their use of resources, but poorer when it comes to fish welfare and vice versa. There’s clearly some way to go to create a more transparent aquaculture industry, but we can see extensive systems with more humane slaughter methods forming a vital part of a food and farming revolution in years to come.

* Including PCBs, dioxins and dieldrin. 

Huge thanks to Public Domain Images for the image (cc)

Our sources

  1. Building a sustainable future for aquaculture: A new impetus for the Strategy for the Sustainable Development of European Aquaculture (2009), Communication from the Commission to the European Parliament and the Council
  2. CIWF (2007), Closed Waters
  3. Jonathan Safran Foer: the truth about fish farming (2010), The Guardian
  4. Global Assessment of Organic Contaminants in Farmed Salmon (2004), Science

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