Enviro-profs studying the ecological impact of food production have come out with some counter-intuitive results. According to a new study, it is greener to eat frozen salmon than fresh, and catching fish en masse in nets does less damage to the planet than taking just a few using hooks and lines.
The new research was carried out by enviro-scientists from Nova Scotia, Sweden, Oregon and Chile. The study focused on salmon, as it is a food produced both from wild and farmed sources by many different methods and consumed all year around the world.
One interesting conclusion of the research is that "food miles" are a largely pointless measure. Far more important than the distance food has travelled before being eaten is the means of travel used.
This is why it is actually more eco-friendly to eat frozen salmon than fresh. Frozen fish can and will be sent by a ship, a very energy-efficient way of moving stuff, even accounting for the power used by freezer containers. Fresh fish, on the other hand, is likely to move mostly by air and road.
It's generally better for the planet to eat frozen grub that's come a lot of food miles than fresh which has travelled fewer miles by air, in fact. According to the enviro-scientists:
The choice to buy frozen matters more than organic vs conventional or wild vs farmed.
There were other conclusions from the study which could be seen as flying in the face of conventional eco-wisdom. According to the assembled boffins:
Catching salmon in large nets as they school together has one tenth the impact of catching them in small numbers using baited hooks and lures.
This directly contradicts the advice offered by Greenpeace, for instance, which says "choose line-caught fish wherever possible".
Deep waters, these.
The study, Not All Salmon Are Created Equal: Life Cycle Assessment (LCA) of Global Salmon Farming Systems, is published here (free) in the journal Environmental Science and Technology. ®