Determining the Status of Fish Stocks in Data-Poor Environments and Multispecies Fisheries

Some of the possible new World Trade Organization rules on fisheries subsidies could apply only when fish stocks are overfished or fishing is unsustainable. How can this be assessed in the context of data-poor and multispecies fisheries?

By Maren Headley on June 18, 2020
  • More than 80% of global catches occur in fisheries that lack the necessary data, resources, and infrastructure to conduct quantitative model-based stock assessments.

Key Messages

  • Developing countries with multi-gear, multi-species, and data-limited fisheries can face particular challenges in using the most common methods to assess fish stocks, which are often based on the concept of maximum sustainable yield.
  • A variety of methods can be used to assess the health of fish stocks. While some of these methods require quantitative data and modelling, others do not, relying instead on the use of expert judgment applied to relatively simple information gathered.
  • In implementing possible new World Trade Organization (WTO) rules on fisheries subsidies, WTO members could use a wide range of “alternative reference points” to establish when a stock is overfished or when overfishing is occurring. These include reference points and corresponding indicators that are more suitable to data-poor and multispecies fisheries.

World Trade Organization (WTO) negotiations on fisheries subsidies aim to discipline the financial support provided by governments to their fishing sector to ensure that it does not have harmful impacts on marine resources and those who depend on them for food and income. The application of some of the possible rules currently discussed by WTO members would depend on whether fish stocks are in an overfished condition or whether overfishing is occurring.

Methods commonly used to assess the health of fish stocks and the sustainability of fishing effort, however, can have substantial data requirements. A key concern in the negotiations is thus how these subsidy disciplines could be applied by governments with little access to data about the state of their stocks. This brief provides an overview of methods for assessing fish stock status in data-poor and multispecies fisheries and highlights some key implications for WTO negotiations on fisheries subsidies.

Report details

Fisheries Subsidies
IISD Global Subsidies Initiative
Focus area
IISD, 2020