Clarifying assessment of inseparable stocks in a catch

Some fisheries catch closely related species that look the same and are impossible to separate.

Such species are referred to as inseparable or practically inseparable (IPI). We want to make sure the MSC Fisheries Standard is clear on how to assess the stocks of these difficult-to-separate species.  


Improving our standard

Concerns have been raised by stakeholders and staff that some of the current requirements for the management of inseparable or practically inseparable (IPI) stocks are not clear or are difficult to apply in practice. We want to clarify and strengthen guidance to make sure our Standards are being applied consistently and effectively. 

We want to provide guidance for IPI designation reference periods, similar to the guidance given for major and minor species in Principle 2 of the Standard. We also aim to revise the requirements to ensure that species which are not permitted as a target species for a fishery (defined as ‘out-of-scope’) are not eligible for classification as IPI. 


How could the standard change?

The changes proposed could lead to a change in the requirements and guidance of the MSC Fisheries Standard. Specifically, there could be changes to the guidance on reference periods and eligibility requirements. 


Progress so far

We have reviewed past Variation Requests and Announcement templates related to IPI catch. Variation requests are submitted by Conformity Assessment Bodies (CABs) to the MSC for permission to vary from a clause or requirements in any of the MSC program documents. It is mandatory for CABs to complete an IPI Announcement when Inseparable or Practicably Inseparable (IPI) stocks are identified. 

We have collated data relating to the reference periods used by CABs for fisheries with IPI catch. Reference periods refer to the time period for which IPI catch compositions are collected.

We have collected and analysed data relating to the different categories of species of IPI catch. This will help determine whether biological characteristics such as reproduction rate should be considered when determining reference periods. We have also analysed the composition of IPI catch to establish whether any out of scope species are being caught. While endangered, threatened and protected (ETP) species are specifically not allowed under IPI rules, we are trying to determine whether species deemed out of scope in MSC certification, such as marine mammals, are being classified as IPI. 


Next steps

Stakeholders are at the heart of our Fisheries Standard Review, helping identify issues, develop solutions and test the possible impacts of any proposed changes. We are holding a series of stakeholder consultation events in 2020 and 2021 including virtual workshops and online surveys. 

Currently there are no open activities related to this project.

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


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