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How to be Ocean Wise when choosing wild and farmed seafood

We can help you!

A lot of people want to buy the sustainable choice for their clients or their dinner table, but they struggle to know what questions to ask or how to deal with the answers they get when they do ask. If this is you, don’t worry! We will show you how we determine our Ocean Wise recommendations by breaking down what makes wild and farmed fisheries sustainable. We will also point you towards resources you can access anywhere or any time on your phone or computer, to help guide you to the best choices. Let us do the work for you!

Oyster Farming

How do I know what WILD fish is sustainable?

Sustainability in a wild fishery depends on a few key factors. With the help of the most up-to-date data available, our sustainability assessment is guided by four key questions:

  1. Is the stock that is being fished abundant and resilient to fishing pressures?
  2. Is the fishery well-managed with a comprehensive management plan based on current research?
  3. Is harvesting done in a method that ensures limited bycatch on non-target and endangered species?
  4. Is harvesting done in ways that limit both damage to marine or aquatic habitats and negative interactions with other species?

The fishing methods and origins of your seafood are important in this investigation. Some fisheries use different methods to collect the same species, with drastically different impacts. For example, harvesting scallops by diving (hand-picking species on the ocean floor with little to no impact on habitat) or dredging (dragging large metal baskets over the ocean floor behind a moving vessel with significant damage to the seafloor and high levels of bycatch). Also, the same species harvested from one region versus another can dictate sustainability. Some fisheries are better managed than others, resulting in healthier stocks or less harmful practices. An iconic example of this is the Pacific cod and the Atlantic cod fisheries, the latter having to be put under moratorium by the Canadian federal government in 1992 because of the fish stock collapse.

Information on collection methods and origin of your seafood isn’t always obvious. If you see an Ocean Wise logo on a product or menu item, then you know the above criteria have been assessed and the seafood is sustainably caught. Can’t find our logo? Ask your server, chef or supplier for the species, harvest method and origin of your seafood. Then look up the species on your phone or computer using the Ocean Wise seafood website .

Congratulations, you are now equipped to do your own personal sustainability investigation!

What about sustainably farmed fish?

Did you know that half of the seafood we consume is farmed? Farming seafood is also called aquaculture (think agriculture but in the water, so aquaculture). With roughly one-third of the world’s fish stocks now overfished, the oceans can’t keep up with demand. Aquaculture is part of a realistic solution now and for the future – as long as it is done sustainably, of course!

When deciding if a farmed fishery is sustainable, we assess numerous criteria specific to aquaculture. With the help of the most up-to-date data available, our sustainability assessment is guided by ten different criteria-based questions:

  1. Is there enough reliable data to make a proper assessment?
  2. What are the effluent outputs into the environment and their impact?
  3. How does the farming operation impact the natural habitats in and around the farm?
  4. What are the chemicals used in the farming process?
  5. What types of feed are used and feed to production rate?
  6. Is there risk of escapes and introduced species into local environments? *farmed species are not always native to the place they are being farmed
  7. What is the risk of disease, pathogens and parasite interaction from the farmed species to the local species?
  8. Where did the seafood species originally come from?
  9. Does the farming operation cause predator and wildlife mortalities?
  10. Is there risk of escape of secondary species brought in to make the farming function (i.e. food sources, pest control, etc.)?

With the variation in aquaculture practices, you inevitably end up with some sustainable and some unsustainable results. Look for the Ocean Wise logo to ensure that these ten criteria have been assessed. If you can’t find our logo, you know what to do (*hint: look at the last section).

Is all farmed seafood created equally?

Just like we have different harvesting methods and resulting environmental impacts for farming on land, the same goes for aquaculture. How can you determine what seafood is sustainably farmed? One large differentiating factor is whether the species is farmed in an open ocean/lake/pond, OR using land-based Recirculating Aquaculture Systems (RAS).

The Northern Divine sturgeon aquaculture farm in Sechelt, BC (Northern Divine)

There are clear differences in risk here if you look at the interaction of the farmed species with local environments. Open net-pens only have a net as a barrier between the farmed species and the natural environment. That means increased risks of escapes; disease or parasite transfer to or from farmed species; waste, effluent produced or chemicals used by farming going directly into the habitat; and, potential predator and wildlife deaths. There are rare examples of sustainable submersible marine net-pen farming (i.e. kampachi in Hawaii), due to their small scale, deep water circulation reducing waste build up, and absence of antibiotics. However, because of the risks common to most open net-pen systems mentioned above, RAS farming ranks higher in sustainability assessments.

Salmon fish farm off the coast Broughton Archipelago near Vancouver Island (Mychayki Prystupa)

Why? The list of risks above are eliminated in RAS farms because the farmed species are contained on land. The circuit is closed, meaning all the water, waste and other materials used are filtered, cleaned and reused continuously within the same system. We currently have partnerships with RAS farms in Canada that produce sustainable Atlantic salmon, Pacific salmon, white shrimp, tilapia, rainbow trout, halibut, white sturgeon and Atlantic sturgeon. Some aquaculture operations even compliment with aquaponics systems, using the waste water to provide nutrients for plant growth. Now that’s smart thinking!

Mussel Farming (Fisheries and Oceans Canada)

It is also important to assess a farmed fishery’s reliance on catch from the wild for feed, and their feed to production rate (i.e. how many kilos of fish feed does it take to produce 1 kilo of farmed fish). If farmed seafood requires fish product from a wild stock that is under pressure, and especially if the return rate is negative, then it could be indirectly contributing to unsustainable practices. Some farmed fish are herbivorous, like tilapia, so they don’t put any additional pressure on marine fisheries for feed. The data assessed by Ocean Wise considers all levels of the supply chain to be able to ensure that each segment meets the sustainability criteria.

Shellfish farming is also very sustainable. Shellfish (i.e. mussels and oysters) are filter feeders. They strain suspended matter and food particles from the water column to eat. They don’t require feed like other farmed species and their filtering capacity improves water quality. Shellfish can also be farmed in high densities, since they remain stationary. There are some potential impacts with larval distribution of non-native species, but farmed shellfish is by-and-large one of the most sustainable options out there. It’s possible that you’ve already been serving, eating or supplying sustainable seafood without even knowing it!

Don’t think we forgot about the vegetarians and vegans out there! Did you know that aquatic plants are harvested from the wild or grown via aquaculture? It’s very likely that your seaweed is sustainably farmed or harvested (maybe even from BC), but it’s always good to double-check before you grab that yummy nori snack.

Seafood takeaways: 

  1. To protect our oceans, it is important to choose sustainably caught seafood. We can make a positive impact with our collective voice and purchasing power.
  2. Look for the Ocean Wise logo: it’s the easiest thing you can do to ensure you’re choosing sustainable seafood. If you’re a chef, owner, retailer, supplier or producer, you can partner with us to put our logo on your menus and products.
  3. Don’t be afraid to ask. Ask your server, chef, retailer or supplier if their seafood is Ocean Wise recommended. If you can’t find our logo, ask what species of fish you are eating, where it came from, and how it was caught or farmed. Then search for it on our website or App. Traveling outside of Canada? Look for other great sustainable seafood programs in the Global Seafood Ratings Alliance.
  4. Support restaurants, retailers, suppliers and fisheries that prioritize sustainability. By increasing the demand for sustainably caught or farmed seafood and raising more awareness, you can move the dial on this issue.
  5. Canadians have a lot of sustainable choices from both wild and farmed fisheries. Moving forward, we can support a large number of sustainably caught and farmed solutions for the health of our oceans.

Sources: 2018. The State of World Fisheries and Aquaculture 2018 – Meeting the sustainable development goals. Rome. License: CC BY-NC-SA 3.0 IGO.

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Written by Laura Irvine, Ocean Wise seafood program Senior Accounts Specialist for Eastern Canada


Posted February 4, 2019 by Ocean Wise

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