Should farmed Salmon eat sustainably?

Contionuing our student posts, this week we have a piece by Lewis Drysdale on the impacts of salmon farming....

The recent “Hugh’s Fish Fight” programmes by River Cottage’s Hugh Fearnly-Whittingstall not only tried to attack the increasing problem of overfishing and “bad” fisheries management but also squared up to aquaculture in UK, an industry that has had more than its fair share of controversies in the last 20 years. Sea lice infestations, fake colourings, chemicals, inter-breeding with wild stock and pollution are issues that consumer is generally aware of through the critics of farmed salmon, most of whom are chefs or food writers as opposed to scientists or industry experts. Hugh has always been a champion of sustainable fish, so why would he attack aquaculture, hailed as the ‘Blue Revolution’ that aims to reduce the pressure on our oceans by offsetting our wild fish needs?

The problem is that conservation groups say that it takes up to 4kg of wild fish to grow 1kg of farmed Salmon, a statistic that may astound the average consumer. In terms of energy transport systems that drive food chains more biomass is needed to feed the next level up the food chain i.e. you need a lot of small fish to feed a bigger fish. Does this mean that Salmon farming is unsustainable? Well, that all depends. If we as consumers, on a higher trophic level than the Salmon, stop eating farmed Salmon and revert back to wild fish then the over-exploitation of our oceans will continue and we will rapidly deplete our fish stocks. However, a recent article in the Guardian reports that fisheries scientists suggest we should be eating more small pelagics because the lack of predatory fish has led to an explosion in the numbers of small fish in the ocean. Hugh’s stance was largely based on a report by the Ecologist that paints a grim picture of fish farming and fishmeal production in Chile where human health and welfare are low priority and Salmon farming is much less regulated than it is in the UK. There is no doubt that UK Salmon feed is largely sourced from South American fisheries of which we do not have a say in the welfare of the workers or fishery management. It is therefore down to us as a consumer to demand transparency and sustainability measures from our producers and suppliers, something that Hugh has always told us to do. I think it is important to try and remember that there is no right answer and we should try to stay as impartial as possible when trying to evaluate an industry like Salmon farming. Hugh’s investigation into Salmon farming can be seen here.