By Laure Latham

Q&A on Fish farming with Geoff Shester, Senior Science Manager at Seafood Watch

Q: Tell us about fish farming

A: In 2009 for the first time, humans ate more farmed seafood than wild-caught seafood. Seafood farming includes shellfish (clams, mussels, oysters) as well as fin-fish farming (salmon, tuna…).

Q: How do you define sustainable fish farming?

A: Three main criteria:

-        how much feed you need to provide

-        do farmed fish diseases spread outside?

-        do farmed fish spread pollution outside?

To find out more, you can look at Seafood Watch’s aquaculture evaluation criteria or read the State of Seafood Report , which contains good images of fish farming techniques.

Q: What can be problems related to fish farming?

A: Salmon is the poster child of what not to do. For every pound of farmed salmon, you need 4 to 5 pounds of wild fish to feed them. People think that by consuming farmed salmon they are relieving pressure off wild caught fish whereas on the contrary, they are increasing the pressure. Nowadays, no farmed salmon option is a good choice.

Some farms are moving very close to land-based tanks but in the current state of salmon farms, salmons get wild parasites in tanks. Due to their high density, they spread the parasites and spread them back to wild fishes. Within a few generations, there will not be any wild salmon left in some British Columbia rivers.

Another problem is farmed fish escape into the wild. These escapes are essentially impossible to prevent. Farmed fish breed with wild stocks and spread diseases. It is one of the problems with tilapia. It is a very aggressive fish that started in Africa and spread all through Asia.

Q: Can sustainable fish farming be done?

A:  To move towards sustainable fish farming, there are basically two options:

-        improve efficiency of the feed and feed the fish something else such as soy

-       grow animals that don’t need feeding at all such as shellfish that feed on nutrients in the water

The best thing would also be to move towards more tank-based systems that are not connected to the ocean. That would reduce a lot of the impact.

Q: What fish do you recommend people buy?

A: Right now if you don’t know where your shrimp or salmon comes from, don’t buy it. We publish pocket guides that people can get for free.  To get up to date information, you can also look for the Marine Stewardship Council’s blue label when buying wild fish.

Seafood Watch publishes a Super Green List of fish and shellfish that are not only sustainable but low in contaminants and high in Omega-3s.  They are healthy and sustainable.

Q: What does organic farmed fish mean?

A: Unfortunately there is no eco label for farmed fish and debates are going strong about national organic standards. In a word, no farmed fish labeled “organic” would be USDA certified. No farmed seafood can be sold in California under the organic label.

Q: Are there places where people can buy sustainable seafood?

A: I have not seen any major retail chain that is going to sell only sustainable fish. However, Andronico’s works with FishWise and labels the fish they sell red, yellow or green. Look for the stuff that’s green or yellow but definitely avoid the red.

It’s important that consumers vote with their dollars and know what species they’re getting, where is it from, and whether it’s wild or farmed.

As far as sushi, it’s tricky because often you can’t recognize the fish. There are a few places on the West Coast, like Tataki Sushi in San Francisco, that are sustainable sushi bars. It can be done!

Please also see an article written by Laure about sustainable fish sticks!