ENVIFISH: an EU/Southern African collaborative project investigating environmental causes of pelagic fisheries variability

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  • Progress in Oceanography 59 (2003) 177179www.elsevier.com/locate/pocean

    Editorial

    ENVIFISH: an EU/Southern African collaborative projectinvestigating environmental causes of pelagic fisheries

    variabilityENVIFISH (Environmental conditions and fluctuations in recruitment and distribution of small pelagic

    fish stocks) was a three-year research project carried out between 1998 and 2001 as part of the EuropeanCommission INCO-DC (International Co-operation Developing Countries) programme. One of its aimswas to enable Developing Countries to be associated with the generation of knowledge and innovativeand appropriate technologies needed to solve their specific problems so as to achieve sustainable develop-ment. Within this framework, the objective of ENVIFISH was to develop appropriate methodologies forimproving the sustainable management of small pelagic fish based on the identification and quantificationof key environmental conditions that influence their recruitment and distribution. The geographical area ofinterest was the Benguela marine ecosystem (encompassing the coastlines of Angola, Namibia and thewest coast of South Africa), which supports large populations of pelagic and demersal fish of considerableeconomic and social importance. As with many other pelagic fisheries worldwide, large fluctuations in thecatch of small pelagic fish in the Benguela region have been observed over past decades. Most dramaticwere the collapse of the Namibian sardine catch, which dropped from 116,000 tons in 1994 to less than2,000 tons in 1996 despite the application of apparently sound management principles, and the recoveryof the South African sardine, from 30,000 tons in 1984 to 260,000 tons in 2002. Considerable work hasbeen devoted to understanding environmental influences on small pelagic fish populations in the regionthrough 15 years of intense, nationally-funded, multi-disciplinary research within the Benguela EcologyProgramme (BEP). ENVIFISH efforts built on fundamental programmes such as the BEP by developingresearch tools for the new decade. The project team comprised ten partners, four of which are Europeanresearch institutions, two are international organisations, and four are institutes from the Benguela region1.

    ENVIFISH conducted a retrospective analysis of environmental and fisheries records from 1982 to 1999.It produced a consistent and quality-controlled database of satellite products: 18 years of sea surface tem-perature data; 7 years of sea surface height data and 3 years of ocean colour data. These remote-sensingproducts were augmented by the excellent regional databases of in-situ data from ships and buoys, enhanc-ing the spatial and temporal coverage of environmental information. Extracting relevant patterns from this

    1 Joint Research Centre (JRC), Ispra, Italy; Instituto de Investigacao Pesqueira (IIP), Luanda, Angola; National MarineInformation and Research Centre (NatMIRC), Swakopmund, Namibia; Sea Fisheries Research Institute (now Marine and CoastalManagement, MCM), Cape Town, South Africa; University of Cape Town (UCT), Cape Town, South Africa; Baltic Sea ResearchInstitute (IOW), Warnemunde, Germany; Plymouth Marine Laboratory, Plymouth, UK; Institute of Marine Research (IMR),Bergen, Norway; Food and Agriculture Organisation (FAO), Rome, Italy; Instituto de Investigacao das Pescas e do Mar(IPIMAR), Lisboa, Portugal.

    0079-6611/$ - see front matter 2003 Elsevier Ltd. All rights reserved.doi:10.1016/j.pocean.2003.09.001

  • 178 Editorial / Progress in Oceanography 59 (2003) 177179

    vast amount of environmental data and relating it to fisheries problems necessitated a substantial degreeof innovative analyses, and it is this area that ENVIFISH has made real progress.

    This volume includes seven papers that contribute to the overall objective of ENVIFISH. The series ofpapers begins with a synopsis of the ocean climate of the South East Atlantic by Hardman-Mountford etal. (a) to set the physical context for the papers that follow. This comprehensive multi-sensor descriptionfrom satellite of the ocean climate in this region should become an invaluable reference source. Many ofthe papers that follow apply modern and flexible statistical techniques to extract pertinent environmentalinformation from remotely-sensed data for fisheries applications. Richardson et al. (a) describe how Self-Organising Maps (SOMs), a type of artificial neural network, can be used to identify patterns in varioustypes of satellite images. They show that the SOM can be used to depict inter-annual, seasonal and event-scale variability in satellite imagery, and that this provides valuable information for fisheries problems.Hardman-Mountford et al. (b) then apply the SOM to remotely-sensed sea surface height data off theNamibian coast to identify enrichment and retention processes, conditions favourable for larval survival.They suggest that the analysis of satellite data using a pattern-recognition approach to identify dynamicprocesses that may be crucial for larval survival provides a useful framework for tackling fisheries recruit-ment problems. Another modern statistical approach employed fruitfully in ENVIFISH is generalised addi-tive modelling (GAM). Daskalov et al. use GAMs to investigate the relationship between sardine Sardinopssagax recruitment in the Northern Benguela and several explanatory variables, including spawning stockbiomass, wind and SST. They find evidence for a reversal in the relationship between recruitment strengthand environmental variables (SST and wind) after 1991, and suggest that this is either the result of aregional climate regime shift or an effect of overfishing. This paper provides an interesting contrast inapproach to understanding recruitment strength: the paper by Hardman-Mountford et al. (b) also investi-gated sardine recruitment in the Northern Benguela but used a very different approach, the SOM. Agenbaget al. employ GAMs and generalised linear models (GLMs) to investigate the effect of environmentalvariables such as lunar cycle and thermal conditions on the abundance of South African anchovy (Engrauliscapensis), sardine (Sardinops sagax) and round herring (Etrumeus whiteheadi) from 130 000 commercialcatch records. This study highlights differences in the effect of environmental factors on fish behaviouramong the main commercial pelagic species in the region. Richardson et al. (b) develop a generic approachusing GAMs and GLMs that will improve regional estimates of primary production, a key index of systemproductivity needed for better fisheries management. They find that the vertical structure of chlorophyll inthe Benguela can be predicted from a suite of environmental variables estimated from satellite. Thisapproach may also have utility in other regions of the world. Finally, Feistel et al. develop a new climaticindex for the South Atlantic for the years 18931999, and find that it is strongly related to events in theBenguela upwelling system. Using this index, they report several years of historical warm Benguela Ninos(1895, 1905, 1916) and years of strong Benguela upwelling (1911, 1921, 1976) that have not been pre-viously identified because of scarcity of data.

    With this series of papers marking the culmination of ENVIFISH, it is timely to highlight some of thedifficulties experienced in the project, as well as the strengths. A major challenge in ENVIFISH wascollaborating remotely between institutions in Europe and Southern Africa. Although difficult, this wasfacilitated by funding regular meetings and workshops between European and Southern African partners.Periods of direct collaboration through exchange of personnel and joint workshops proved to be the mostfruitful in the project.

    One of the most important initiatives within the ENVIFISH programme was capacity building withinthe Southern African region. The project had a strong training component, supporting five African studentswho completed postgraduate degrees. These students as well as other Southern African researchers werefunded to attend overseas meetings, conferences and advanced training workshops. This legacy will helpprovide skilled marine scientists in the region for the future. ENVIFISH also facilitated links betweenSouthern African marine science and international scientists and programmes, helping to strengthen marine

  • 179Editorial / Progress in Oceanography 59 (2003) 177179

    research in Southern Africa. ENVIFISH was implemented in coordination with the bilateral French-SouthAfrican IDYLE programme. Both ENVIFISH and IDYLE are regional contributions to the internationalSmall Pelagic Fish and Climate Change Programme (SPACC), a GLOBEC (Global Ocean EcosystemDynamics, www.globec.org) programme that attempts to understand and ultimately predict climate-inducedchanges in pelagic fish productivity in the major marine ecosystems. This partnership culminated in a jointGLOBEC-SPACC/IDYLE/ENVIFISH workshop in Cape Town in 20012.

    It is hoped that this series of papers is a valuable contribution to marine science knowledge in SouthernAfrica, and will provide a useful input for the new large Benguela Current Large Marine Ecosystem(BCLME) programme. The ENVIFISH team would like to thank the European Commission for their finan-cial support (EU contract IC18-CT98-0329). The team warmly acknowledges the collaborative opportunitiesoffered from the French-South African IDYLE programme and GLOBEC-SPACC.

    Manuel Barange,GLOBEC International Project Office, Plymouth Marine Laboratory, Prospect Place,

    Plymouth PL1 3DH, UKE-mail address: m.barange@pml.ac.uk

    Leo Nykjaer,Joint Research Centre, Institute for Environment and Sustainability, I-21020 Ispra (Va), Italy

    E-mail address: leo.nykjaer@jrc.it

    2 See Van der Lingen, C.D., Roy, C., Freon, P., Barange, M., Castro, L., Gutierrez, M., Nykjaer, L. and F. Shillington (eds.).2002. Report of a GLOBEC-SPACC/ IDYLE/ ENVIFISH workshop on spatial Approaches to the Dynamics of Coastal PelagicResources and their Environment in Upwelling Areas. GLOBEC Report 16,1- 97.

    ENVIFISH: an EU/Southern African collaborative project investigating environmental causes of pelagic fisheries