Cows have been overtaken by fish. For the first time in modern history, the world has been producing more farmed fish than farmed beef. But instead of being a boon for the environment, many fish farms are damaging it because of the types of fish they breed.
A report by the Earth Policy Institute in Washington DC has found that farmed fish production is rising rapidly, reaching a record 66 million tonnes in 2012. Cattle farm output, by contrast, has levelled off, with just 63 million tonnes of beef produced in the same year.
If current trends continue, humans are set to consume more farmed fish than wild-caught fish by 2015, says the Organisation for Economic Co-operation and Development.
Some farmed fish are good for the environment. Chinese aquaculture, which accounts for 62 per cent of the world's farmed fish, relies heavily on species such as silver carp. These can be grown on rice paddies and feed on grass, plankton and detritus. This relatively sustainable way of farming fish boosts rice yields and produces little pollution.
However, other popular farmed species such as salmon are carnivorous. They must be fed on smaller fish like anchovies, caught from the wild. As a result, salmon can only be farmed by further depleting wild fish stocks. "It would be preferable to shift the balance back in favour of farmed fish raised without feeds based on protein from other animals," the report concludes.
This article will appear in print under the headline "Fish leave cows standing"
- New Scientist
- Not just a website!
- Subscribe to New Scientist and get:
- New Scientist magazine delivered every week
- Unlimited online access to articles from over 500 back issues
- Subscribe Now and Save
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
Have your say
Only subscribers may leave comments on this article. Please log in.
Only personal subscribers may leave comments on this article
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.
