Rankings cut guesswork in sustainable fish farming

A league table of sustainable fishmeal sources will help fish farms be eco-friendly, but questions remain over the environmental impact of aquaculture.

It takes around 6 tonnes of wild fish to reduce to 1 tonne of fishmeal, and then anything from 1.5 to 3 tonnes of meal to produce 1 tonne of farmed salmon. Producing fishmeal and fish oil for fish farming is in itself a waste of tasty fish that could be eaten directly.