One of the great ironies of salmon farming lies in the fact that even though the salmon themselves aren't wild-caught, their feed is partially made up of smaller fish that are. According to new research, it would be ecologically better if we just ate those feed fish ourselves.
The study was conducted by scientists from the University of Cambridge, utilizing data from the production of farmed salmon in Scotland for the year 2014. In a nutshell, the researchers wanted to compare the volume of wild-caught feed fish to the volume of farmed salmon that was harvested.
It was found that in 2014, 460,000 tonnes (507,063 tons) of wild-caught fish were used to produce 179,000 tonnes (197,313 tons) of salmon. Furthermore, 76 percent of the wild-caught fish were species that are commonly eaten by humans, such as anchovies and sardines.
Extrapolating those figures to a global scale, the scientists estimate that if people were to eat the wild-caught fish which are currently used in salmon feed, almost 4 million tons (3.6 million tonnes) of fish that are presently caught could be left in the sea each year. At the same time, a greater volume of fish would become available as a human food source.
That said, the researchers do admit that their figures are based on salmon production for one country, during one year. Further larger-scale research will need to be conducted, although it is believed that subsequent studies will paint a similar picture.
"Allowing salmonid production to expand further via its current approach will place exceptional stress on global fish stocks already at their limit," said the authors of a paper on the research. "Our results suggest that limiting the volume of wild-caught fish used to produce farmed salmon feed may relieve pressure on wild fish stocks while increasing supply of nutritious wild fish for human consumption."
The paper was recently published in the journal PLOS Sustainability and Transformation.
It should also be noted that various studies are looking into ways of replacing the wild-caught fish used in commercial aquaculture feed with more sustainable alternatives such as oil-rich algae.
Source: PLOS via EurekAlert
Science has shown that fishes, and other aquatic animals, are sentient. They can suffer fear and pain, and they very much do by being fished/farmed/slaughtered. As sentient beings they deserve respect and moral consideration not gratuitous cruelty. Leaving the fishes in the water also makes them available for the humans and other animals who genuinely need to eat them in order to survive.
This makes perfect sense from an energy pint of view. Each time a conversion takes place we lose something because of inefficiency.
They are saying that it takes 500,000 tons of raw fish to farm 200,000 tons of salmon and that more people could be fed straight from the raw fish.
Just as instead of letting cattle convert grass to meat some would have us just eat food grown directly off the land.
Of course this does not take into account that I like to eat salmon and beef and do not want to substitute it for sardines and lettuce.
@Carolyn There are plans to go straight from insects to people I have read articles on it . Apparently that is a very efficient way to create protein. Got to save the planet you know.
Soyulent Green anyone?
We have to start looking at what we can do to produce food sustainable without destroying the environment and ecosystems. A good start would be population reduction.
So, there really is a "YOU" in "Soylent Green"!