Tag: fisheries

On using catches to predict abundance

Factions among the fisheries community disagree on whether catch data – the amount of fish drawn from the sea – can be used to assess the health of fish stocks. In a comment piece published in Nature today, the Sea Around Us Project’s Principal Investigator Daniel Pauly shares his views, emphasizing that catch data are often the only type of data we have to tell anything about the status of fisheries.

While developed countries such as the US, Australia and those in Europe are able to use a variety of data, such as size, growth and migration information, as well as survey data, to conduct expert stock assessments, Pauly points out that these come at a cost: anywhere from US$50,000 to millions of dollars per stock. Such costs are not feasible for the majority of developing countries. Furthermore, for 80% of maritime countries, catch is the only data available.

In a second comment piece, Ray Hilborn and Trevor Branch from the School of Aquatic and Fishery Sciences, University of Washington, argue that there are other factors beyond the health of a fish stock that can account for changes in catch. Used on their own, catch data can create confusion and alarm about the abundance of fish stocks, they say.

Pauly agrees that catch data should be used with caution, but adds there is danger in undermining the value of this information. In most countries, the amount of fish caught is the only information available to assess stock health. “If resource-starved governments in developing countries come to think that catch data are of limited use, the world will not see more stock assessments; catch data will just stop being collected,” says Pauly.

The Sea Around Us Project, under the guidance of Pauly, is currently conducting a global evaluation of catch data, from 1950 to present, collated by the Food and Agriculture Organization (FAO) of the United Nations. Results so far reveal that many countries have underreported their catches. The extent of the underreporting is larger in developing countries (about 100-500%; Zeller et al. 2007) than in developed ones (30-50%; Zeller et al. 2011).

To see the full article, please go online to Nature.com: Pauly D (2013) Comment: Does catch reflect abundance? Yes, it is a crucial signal. Nature 494: 303-305.

Zeller D, Booth S, Davis G and Pauly D (2007) Re-estimation of small-scale fisheries catches for U.S. flag island areas in the Western Pacific: The last 50 years. Fishery Bulletin 105: 266-277.

Zeller D, Rossing P, Harper S, Persson L, Booth S and Pauly D (2011) The Baltic Sea: estimates of total fisheries removals 1950-2007. Fisheries Research 108: 356-363.

The Sea Around Us Project returns to West Africa

by Duncan Copeland and Dyhia Belhabib

Healthy and well-managed marine environments are essential for ensuring food security, reducing poverty and promoting marine conservation in West Africa. Yet the region faces enormous challenges in achieving these goals, not least of which are poor or even non-existent data relating to fisheries, biodiversity and the impact of human activities.

The Sea Around Us Project is increasingly focusing on data-deficient regions of the oceans, particularly in the developing world. West Africa has been highlighted as a priority region, and in the past few months, the “Sea Around Us Project and PRCM: Marine Conservation Research, Collaboration and Support in West Africa” has been launched. Funded by the MAVA Foundation, the project will address the serious deficiency of adequate data in areas such as capture fisheries and biodiversity at the local, national and Large Marine Ecosystem levels in West Africa.

The Regional Marine and Coastal Conservation Programme for West Africa (PRCM) brings together an important coalition of non-governmental organizations to work with local and regional stakeholders and coordinate efforts to preserve the littoral zone of coastal countries in the region, which includes Mauritania, Senegal, The Gambia, Cape Verde, Guinea-Bissau, Guinea and Sierra Leone. Crucially, the PRCM has promoted cooperation with public sector and civil society organisations to achieve marine conservation, fisheries and integrated management support goals.

However, the challenges facing the success of these initiatives are significant. Limited government capacity and poor regulation; illegal, destructive and over-fishing by industrial fleets; high local dependence on marine resources for livelihoods and food security; and the limited number of marine protected areas in the region all contribute to a difficult environment for achieving effective fisheries and marine conservation. Yet perhaps the greatest impediment to sustainable fisheries management and marine conservation in West Africa is the current deficiency, accessibility and usage of adequate data.

The region has seen limited national and international resources put towards adequate assessments of marine capture fisheries and biodiversity. As a result, decision-making in fisheries management at the local, national and regional levels, as well as in a variety of conservation projects, is often based on limited science. The imperative is to improve the data upon which fisheries management and conservation depends, and ensure that PRCM stakeholders receive support in the utilisation of data within specific marine conservation and fisheries management initiatives.

The Sea Around Us West Africa programme aims to accomplish three complementary objectives, all directly contributing to regional marine conservation, fisheries management and integrated management support objectives. These are to:

• Increase the quality of available data relating to existing and new initiatives promoting marine conservation and fisheries management in West Africa through the development of catch and effort reconstructions.

• Develop strong collaborative relationships between the Sea Around Us Project and proposed project partners; engagement of a wider number of government, research and non-governmental partners will be achieved.

• Raise broader international awareness and support for marine conservation in the region via the publication of peer-reviewed articles and engagement of media.

To achieve these aims, the project is supporting targeted research on catch, effort and catch values, biodiversity, marine protected areas, and other related issues. Crucially, this information will be developed within a partner support framework, ensuring that PRCM member and partner initiatives benefit not only from the generated data, but also have improved organisational expertise to integrate the data into existing and future initiatives. These partners include the Sub-Regional Fisheries Commission (SRFC), local research institutions and the members of the PRCM (WWF, IUCN, Wetlands International and International Foundation for the Banc d’Arguin). Data analysis and visualisation models will be used to achieve these goals in collaboration with PRCM members and other relevant stakeholders.

Through these partnerships, the Sea Around Us Project and PRCM project provides an innovative and supportive approach that will directly contribute to strengthened national, regional and international cooperation in the short and longer term. The programme is specifically designed to offer potential extension beyond the initial proposed two-year period and a model for replication in other regions of the developing world with data-deficient fisheries. In addition, the project will work as much as possible with individuals that are nationals of the target countries, improving expertise in the region.

Marine habitats in West Africa are considered among the most data-deficient globally. With an increased focus on the developing world and growing experience working in the West African region, the Sea Around Us Project is uniquely placed to collaborate with project partners to generate strategic data and support that will directly benefit conservation, fisheries and management goals.

Analysis of FAO Report on Fisheries Statistics

Global fisheries statistics must be viewed with a critical eye. Fisheries landings data are collated by FAO and contributed by all member countries, which have varying resources and motives. In a new paper recently published in Marine Policy, Daniel Pauly and Rainier Froese take a close look at FAO’s State of the Worlds Fisheries and Aquaculture’ (SOFIA) report from 2010 and discuss the FAO’s history, as well as the implications, imperfections, and possible improvements to be made to fisheries data.

Pauly and Froese are both complimentary and critical. They point out the misleading use of the word ‘stability’ in the report as it refers to global catch data from 2005-2008, and point out that even if that global catches are indeed stable, fishing effort is rapidly expanding. They note the FAO’s acceptance of scientific data that showed China does not know how much its fisheries catch, and the large degrees of uncertainty around global trends this problem creates. Pauly and Froese point approvingly to SOFIA’s position on assemblage overfishing and their statement: ‘ We do not disagree that a general decline in mean trophic level of marine landings is likely to have occurred in many regions.’ Finally, Pauly and Froese call for cooperation between institutions, e.g., U.N. technical organization and civil society, as represented by universities and non-government organizations, to improve SOFIA reports and potentially the management of fisheries globally.

To read the full article click here.

Citation: Pauly, D. & Froese, R. 2012. Comments on FAO’s State of Fisheries and Aquaculture, or ‘SOFIA 2010’ Marine Policy 36: 746-752.