IUU fishing is illegal, unregulated, and unreported fishing.  According to the 2001 FAO International Plan of Action to Prevent, Deter and Eliminate Illegal, Unreported, and Unregulated Fishing,

Illegal fishing refers to activities:

  • conducted by national or foreign vessels in waters under the jurisdiction of a State, without the permission of that State, or in contravention of its laws and regulations;
  • conducted by vessels flying the flag of States that are parties to a relevant regional fisheries management organization but operate in contravention of the conservation and management measures adopted by that organization and by which the States are bound, or relevant provisions of the applicable international law; or
  • in violation of national laws or international obligations, including those undertaken by cooperating States to a relevant regional fisheries management organization.

Unreported fishing refers to fishing activities:

  • that have not been reported, or have been misreported, to the relevant national authority, in contravention of national laws and regulations; or
  • undertaken in the area of competence of a relevant regional fisheries management organization which have not been reported or have been misreported, in contravention of the reporting procedures of that organization.

Unregulated fishing refers to fishing activities:

  • in the area of application of a relevant regional fisheries management organization that are conducted by vessels without nationality, or by those flying the flag of a State not party to that organization, or by a fishing entity, in a manner that is not consistent with or contravenes the conservation and management measures of that organization; or
  • in areas or for fish stocks in relation to which there are no applicable conservation or management measures and where such fishing activities are conducted in a manner inconsistent with State responsibilities for the conservation of living marine resources under international law.

Portuguese naval officers and Gabonese sailors inspect a holding bay for fish aboard an illegal fishing vessel.


While all three types of IUU fishing result from a lack of resources (to enforce, report, and regulate), lumping these three different types of fishing under one category simplifies the complex issues, linking illegal activities (i.e., illegal fishing) with legal activities (i.e., unreported and unregulated fishing).  Illegal fishing is a regulatory issue; unreported and unregulated fisheries do not break any law – they are management issues, or rather a lack of management issue.  IUU fishing often basks in a negative light, but this legal distinction makes it difficult to chastise fishermen just because their government lacks the capabilities to report or regulate their fishery. (fishionary.fisheries.org/iuu-fishing) For more information on the challenges to managing IUU fishing, please refer to the following AFS publication:

Serdy, Andrew.  2011. Simplistic or Surreptitious? Beyond the Flawed Concept(s) of IUU Fishing.  Pages 253-279 in W.W. Taylor, A.J. Lynch, and M.G. Schechter, editors.  Sustainable Fisheries: Multi-Level Approaches to a Global Problem.  American Fisheries Society, Bethesda, Maryland.