Good Fish Guide

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Program Overview
Marine Conservation Society

The Marine Conservation Society (MCS) is the UK charity dedicated to protecting our seas, shores and marine wildlife. Our seas are under threat – too much is being taken out, too much thrown in and too little is being done to protect our precious wildlife. MCS works to turn the tide on the neglect of our oceans. MCS believes consumers and businesses have a key role to play in securing the future health of our seas and marine wildlife by making environmentally responsible choices when buying seafood. This means avoiding fish that have come from poorly managed fisheries or fish farms that have a high environmental impact, in favour of buying fish from well-managed sources with a lower impact that are better for our seas and oceans.

By producing and communicating seafood ratings via its Good Fish Guide (first published in 2002), MCS aims to help UK consumers and businesses make the right choices. 

MCS recognizes that fishing and fish farming are not only businesses but a way of life that makes an important contribution to both our economy and society. When fisheries and farms are well-managed, they are more stable and profitable, which in turn means we have healthy seas that can support local communities long into the future. MCS uses fish ratings to identify environmental issues within fisheries and fish farms that need help to improve. Importantly, ratings are also used to highlight best practices and to encourage demand and support for the best environmental performers. 

MCS wants to see an increase in the number of ‘green’ rated (Best Choice) fish and a reduction in ‘red’ rated species (Fish to Avoid). 

MCS ratings are underpinned by scientific information from respected and peer-reviewed sources. Public consultations and ratings updates are undertaken twice a year. Most wild capture ratings are reviewed annually. Farmed fish ratings are reviewed and updated on a 3-year basis, with an annual “health check” for key species. New assessments and re-evaluations can also be triggered if there is a significant change that is likely to affect the environmental performance of the fishery or fish farm.

MCS Good Fish Guide Ratings underpin the sustainable seafood criteria of various UK sustainability initiatives such as: Fish2Fork, the Sustainable Restaurant Association; the Soil Association’s ‘Food for Life Served Here Award’; Sustainable Fish Cities; and the UK Government Buying Standards. Various businesses have made commitments to responsible seafood sourcing based on GFG ratings, ranging from supermarkets, large contract caterers and the London Olympics Committee, to individual restaurants and fish n' chip shops. 

Rating Criteria

Good Fish Guide Standards

MCS assigns ratings to both farmed and wild-caught fish. These ratings reflect the sustainability and environmental impact of the fishery or production method in question and are a way of communicating the relative sustainability of seafood in an easy to understand and familiar “traffic light” format. The MCS Good Fish Guide uses five different colors – from dark green to red – to represent each of the 5 ratings. 

Fisheries Sustainability Criteria:

Unit of Assessment: is typically a specific species, from a specific geographic stock, fished with a specific method, all being managed in the same way

Criteria:

  • Stock or Species Status - the state of the stock size and fishing pressure against the current size of stock
  • Management - an assessment of the measures, monitoring, surveillance, and enforcement to maintain stock size
  • Ecological Impacts of the Capture Method - assessment of fishing impacts on non-target species and habitat and measures to mitigate impacts 

The three fisheries criteria are weighted based on priority of importance as determined by MCS to have the most significance for overall sustainability. This weighting is:

  • Stock of Species Status x 6
  • Management x 5
  • Ecological Impacts of the Capture Method x 4

Aquaculture Sustainability Criteria:

Unit of Assessment: is limited to a specific species, within a geographic area (i.e. region or country), using the same aquaculture production system

Criteria:

  • Feed Sourcing and Use - traceability, sourcing, and ingredient composition (both marine and non-marine) of feed
  • Environmental Impacts and Interactions - traceability, sourcing, and ingredient composition (both marine and non-marine) of feed
  • Fish Welfare - slaughter methods and disease outbreaks
  • Regulations and Management - planning, strategic assessment, regulation, enforcement, and third-party certification standards 

Seafood Recommendations

Symbol

Seafood Rating

Seafood Rating Summary

Good Fish Guide Scoring
Best Choice Indicate fish that are in MCS’s opinion, the best choice and come from well-managed fisheries and fish farms that have a lower impact on the marine environment.

Wild Fisheries: Final score <2.5

Aquaculture: Final score ≥9
Best Choice Indicate fish that are in MCS’s opinion, the best choice and come from well-managed fisheries and fish farms that have a lower impact on the marine environment.

Wild Fisheries: Final score ≥2.5 and <5

Aquaculture: Final score between 4 and 8
Think

 Indicate fish that MCS would like people to eat less of until the fishery or farming method improves. These choices may be at risk of becoming unsustainable because of one or more environmental impacts.

Wild Fisheries: Final score ≥5 and ≤7.5

Aquaculture: Final score between -2 and 3
Think Indicate fish that MCS would like people to eat less of until the fishery or farming method improves. These choices may be at risk of becoming unsustainable because of one or more environmental impacts.

Wild Fisheries: Final score >7.5 and <10

Aquaculture: Final score between -3 and -10
Red Improver Indicate fish which have been assessed and rated 5 (red) due to significant environmental concerns, but credible efforts to improve the fishery or farming system have been agreed through a Fishery or Aquaculture Improvement Project. MCS encourages environmental improvements in fisheries and fish farms, and so does not recommend avoiding these fish, as normally for seafood rated 5.

Wild Fisheries: Final score ≥10 (Max score of 15)

Aquaculture: Final score ≤-11
Avoid MCS would like consumers and businesses to avoid buying MCS red-rated fish until improvements in its production are made.

Wild Fisheries: Final score ≥10 (Max score of 15)

Aquaculture: Final score ≤-11