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Illegal Fishing Prevention

Fishing activities that are illegal, unreported, or unregulated (IUU) can harm fish stocks and damage marine ecosystems. They also undermine the efforts of responsible fishers and fisheries managers.

IUU fishing benefits unscrupulous vessels in the short run and harms the seafood industry in the long term.

ISSF focuses on proactively eliminating illicit fishing practices over time through a multi-pronged approach, which includes conservation measures, initiatives, tools, and outreach to Regional Fisheries Management Organizations (RFMOs).

Transshipment Management

We assess tuna RFMOs’ transshipment regulations for fleets, which can help to prevent illegal-fishing activities, against best-practice recommendations.

Electronic Monitoring

Electronic monitoring systems (EMS) on vessels can track catch, bycatch, transshipment, and landings, and also are a powerful tool for detecting IUU fishing.

Vessels on Illegal Fishing Lists

Trygg Mat Tracking (TMT) maintains a Combined IUU Vessel List with up-to-date information on all vessels appearing on the lists of IUU fishing vessels published by Regional Fisheries Management Organizations (RFMOs).

It also lists fishing vessels that have been subject to a public Interpol Purple Notice.


Unique Vessel Identifiers

To help prevent illegally caught tuna from entering the seafood supply chain, we partnered with seafood companies to make permanent and unique vessel identifiers (UVI) — which facilitate vessel tracking and allow seafood traceability — a standard practice.

Our IMO/UVI Vessel List includes all tuna fishing vessels with an IMO number. It also lists vessels not eligible for an IMO that are using either a Tuna Unique Vessel Identifier (TUVI) or an ISSF-UVI as an alternative UVI.

We issue ISSF-UVI numbers to vessels that cannot obtain an IMO number and do not have a TUVI number.

Public Vessel Lists

In addition to the IMO/UVI Vessel List, we manage other vessel lists that help to improve transparency and sustainability in tuna fishing:

Conservation Measures & Compliance

ISSF participating companies commit to conform to our conservation measures on IUU fishing.

These measures ask participating tuna processors, traders, importers and markets to avoid transactions with vessels that are not flagged to the relevant RFMO member or cooperating non-member (unless the country has applied for such status).

We also urge them to refrain from transactions in tuna caught by:

  • Vessels on a tuna RFMO IUU list
  • Vessels not on the authorized vessel record of the relevant RFMO
  • Vessels of the size subject to listing on the relevant RFMO’s authorized vessel record and capable of being registered by IMO that have not registered with IMO and received an IMO or UVI

Recommendations & Best Practices

ISSF supports RFMOs and their member governments in improving governance, science-based decision making, enforcement, and compliance. We also track tuna RFMO progress in implementing best practices to prevent IUU.

We promote Monitoring, Control and Surveillance (MCS) approaches in tuna fisheries for IUU prevention, including:

  • Trials of electronic observer systems aboard tuna purse seine and longline vessels, disseminating best practices to sub-regional organizations and RFMOs for implementation
  • Vessel Monitoring Systems (VMS) best practices, including for the development of new regional and national VMS programs
  • RFMO transshipment requirements for longliners and purse seiners

We cover these and related topics in our scientific and best practices reports and also publish research findings in peer-reviewed articles.


IUU Vessel Listing

Every year, we update our “snapshot” that summarizes best practices in IUU vessel listing — and shows each RFMO’s progress in implementing them.

The snapshot complements our best-practices report, ISSF 2022-08: Combatting IUU Fishing: Continual Improvement and Best Practices for IUU Listing Measures in Tuna RFMOs.

RFMO Authorized Vessel Lists

We report on best practices in RFMO authorized vessel lists, which are fundamental to robust fisheries management.