Clarifying assessment of dynamic fisheries

Dynamic fisheries target species whose population size can vary greatly over time and with changing environmental conditions.

The MSC Fisheries Standard requires that harvest strategies are robust and precautionary and take into account the variability and uncertainty of dynamic fish stocks.  

Improving our standard

The inherent variability of stock sizes, also known as 'yo-yo' tendencies, means that some fisheries may experience changes to their certification status throughout the five-year lifespan of a certificate. These status can lead to uncertainty for fisheries.  

Through the Fisheries Standard review, we aim to identify the risks in maintaining certification for fisheries experiencing fluctuations in stock size. We will also aim to establish whether there is benefit in using historical reference points, such as historical biomass trends to assess stock sustainability, and whether dynamic or static reference points are more effective. 

We aim to develop new guidance that will help to clarify the intent of the MSC Fisheries Standard for dynamic fish stocks, including the assessment of short-lived, environmentally-driven species such as crab, squid and octopus.

We also aim to assess the use of proxy methods, such as fishery mortality for short-lived species to demonstrate that their stock status is at a level consistent with maximum sustainable yield (MSY). This is defined as the largest catch that can be taken from a fish stock each year without causing long-term depletion of their future population size.


How could the standard change?

The changes could lead to new guidance for the MSC Fisheries Standard, aiming to make the Standard more accessible to fisheries harvesting dynamic stocks. It is not anticipated that new requirements or bespoke assessment trees will need development.

The proposed changes could include guidance on how to use proxy indicators and reference points for scoring in Principle 1 of the MSC Standard. Guidance could also be provided for how to assess trends in fishery mortality and harvest control rules for dynamic stocks.

Progress so far

We have reviewed fishery assessments to identify the prevalence of fisheries with 'yo-yo' tendencies and investigated the causes behind their change in certification status. We have also reviewed how the MSC Standard is applied in relation to squid and octopus fisheries.


Next steps

We are currently drafting new language and guidance on how Principle 1 requirements should be applied to dynamic stocks.  

Throughout 2021, we will carry out pilot assessments and seek guidance from our Technical Advisory Board. This will make sure any changes to our Standard are feasible and achieve the expected outcomes. 

By the end of 2021, we will have drafted a revised MSC Fisheries Standard, which will be reviewed by our governance bodies.

In early 2022, stakeholders will have an opportunity to review all proposed changes before any final decision to revise the Standard is made.

The new Standard will be released later in 2022 following approval from our Board.


Sign up to our Fisheries Standard Review mailing list to receive updates about the review, engagement events and consultations.

  • '{{item.Image.Title}}', {{item.Image.Artist}}, {{item.Image.Description}}