Ask for fish from sustainable sources - Wiki Thing

Benefits of buying fish from sustainable sources, and carbon saved

Fish is one of those things that we're generally encouraged to eat more of, being a lean source of protein, and oily fish in particular is good for our brains and is thought to have lots of other health benefits. ¹

The problem is, intensive fishing practices as well as our preference for the same few varieties means many species of fish end up being overfished. Some fishing methods, like bottom-trawling and dredging, destroy the sea-bed and everything on it, or use methods which indiscriminately trap birds and other sea animals. They also tend to be more fuel, (and therefore carbon) intensive as boats travel further afield and go to extra lengths to ensure high catch volumes. Fishing boats are responsible for around 130 million tonnes of CO2 a year, resulting in emissions of around 1.7 tonnes of CO2 per tonne of live landed fish. Switching from dredging and trawling to more sustainable and passive methods of fishing is kinder to the marine environment and ecosystem in general; some methods can cut fuel consumption by between 4 and 15 times, reducing CO2 emissions considerably. ²

Carbon saved from eating sustainably-sourced fish:

According to Seas At Risk, ³ a European group of NGOs working to protect and restore the marine environment, conventional methods of fishing can, on average, result in emissions of 1.7 tonnes of CO2 per tonne of fish caught.

A typical portion of fish can weigh between 110g to 300g depending on the fish, and the type of dish, but average portion sizes seem to be around 175g.

So CO2 released per portion:
1.7 kg per 1 kg
x kg per 0.175 kg = 1.7 x 0.175 kg = 0.30 kg CO2 per portion of conventional fish.

According to Seas At Risk, fishing sustainably can use at least 4 times less fuel, and in some cases up to 15 times less. Taking a mid-way estimate that sustainable fishing techniques will reduce fuel consumption by a factor of 10, then

0.1 x 0.3 = 0.03 kg CO2 per portion of sustainable fish

Therefore carbon saved by fishing sustainably = 0.30 kg - 0.03 kg

= 0.27 kg CO2 saved per portion of sustainable fish consumed.

Useful Resources

Seafish
http://www.seafish.org

Responsible Fishing Scheme
http://rfs.seafish.org/ 

Marine Conservation Society
http://www.mcsuk.org/

Seas At Risk
http://www.seas-at-risk.org 

Footnotes

Footnotes

Reference Notes

1 http://www.nutrition.gov.uk/healthydiet/nutritionessentials/fishandshellfish/

2 Seas at Risk http://www.seas-at-risk.org/n3.php?page=138

3 Seas At Risk http://www.seas-at-risk.org