The Institute for the Oceans and Fisheries of the University of British Columbia in Canada recently published a report, “Assessments of Marine Fisheries Resources in West Africa with Emphasis on Small Pelagics” based on the study conducted by the Sea Around Us, the MAVA Foundation and the Commission Sous-Régionale des Pêches, (CSRP). To bring novel stock assessment methods by Froese et al. in West Africa, they hosted a training course, the “Use of the CMSY Tool for the Assessment of West African Stocks” in Dakar, Senegal with participants from Cape Verde, The Gambia, Guinea, Guinea-Bissau, Liberia, Mauritania, Senegal, and Sierra Leone. For the said course, The FishBase and SeaLifeBase teams provided assistance by preparing the resilience and biomass ‘priors’ provided to the participants and ensuring the coverage of the small pelagic species occurring in the region.
The stock assessment methods that were introduced, CMSY and LBB, require a minimum of data to provide estimates of B/BMSY, i.e., the current biomass of an exploited stock relative to the biomass that generates maximum sustainable yield (MSY). The participants learned and applied these methods based on the available data that they brought with them at the workshop, and contributed their corresponding results and papers to this report. Half of the assessments in the new Fisheries Centre Research Report (FCRR) were from those carried out by country representatives and academicians in the the said workshop. Although a number of applications were preliminary, they highly suggest the suitability of CMSY and LBB methods in the CRSP region.
To supplement these information and preliminary findings for Northwest African stocks, the Sea Around Us team conducted 14 more assessments based on reconstructed catch data combined into ‘marine ecoregions,’ on 11 species of small pelagic fishes from the 8 countries in question.
Findings of the final report reveals that preliminary assessment of 26 fish and invertebrate populations that live in the waters of eight West African countries are likely overfished or at risk of being overfished if not strongly overexploited such as the cassava croaker off the coast of Liberia.
Specifically for cassava croaker, lead editor of the report Dr Ma. Lourdes ‘Deng’ Palomares (Sea Around Us’ project manager) says “the analyses yielded that its biomass as of 2018 is only 34% of its level in 2009, which was then already much reduced from its original abundance.” Moreover, “these results corroborate the IUCN Red List findings, which assigned this species to the ‘Endangered’ category in 2009,” she added.
Populations of Bonga shad in The Gambia, southern pink shrimp in Guinea-Bissau, European anchovy in Mauritania and round sardinella in Senegal also showed signs of overfishing. In all 26 cases, the call is for prudent fisheries managers in the region to recommend a reduction of fishing effort until these stocks show signs of recovery.
Sea Around Us’ Principal Investigator Daniel Pauly aspires to convince scientists and decision-makers in the CSRP region, through these efforts and contributions, that data can be found and stock assessments can be performed, and that they acknowledge and report that fishing effort in the region is excessive. He highly recommends a reduction of fishing effort which would allow West African stocks to rebound, and allow greater catches.