Fish stock update
The small pelagics stocks are shared stocks, so the scientific assessments of stock status take place at regional level, by a collaborative group of scientists from the different relevant countries, under the auspices of CECAF, managed by FAO (the small pelagics north working group). This working group meets every year to compile all the available data and conduct stock assessments, usually trialling a range of different models, suited to data availability and robustness.
According to sampling by IMROP, the species composition of landings by the coastal seiner fleet in recent years has been ~two thirds sardine, with the other one third mainly flat sardinella, with small amounts of round sardinella, mackerel and horse mackerel.
Figure. Landings of the coastal seiner fleet, which supplies the fishmeal factories and their associated freezing plants, 2019-2022 (data from IMROP)
According to the conclusions of the CECAF working group for 2023:
• Sardine – stock healthy
• Sardinellas – overexploited; round sardinella severely overexploited, flat sardinella probably also overexploited
• Mackerel, horse mackerel – fully but not over-exploited
Management of fish stocks in Mauritania is the responsibility of the Ministry of Fisheries and the Maritime Economy, with scientific advice from IMROP. Management measures are based on the strategy for the fishery set out in the Small Pelagic Fishery Management Plan (Plan d’Aménagement de Pêche – petits pélagiques, November 2022).
The management plan continues the general thrust of policy in recent years, i.e. working to control landings of sardinella to recover the stocks, and moving the whole fish landings increasing towards the human consumption supply chain, with fishmeal production focusing on by-products and waste.
As well as the quotas and restrictions on sale set out above, the fishery is also managed via a zoning system, which aims to keep the larger pirogues and the coastal seiner fleet further offshore. The intent of this is to ensure that the smaller artisanal vessels can fish without too much competition, and also to keep the larger vessels away from depleted inshore stocks such as bonga (not in fishmeal), as well as juvenile sardinella and sardinella spawning areas. For the coastal fleet, the zoning can be enforced by VMS.
The data required to analyse stock status and provide scientific advice for management is collected from several sources:
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The vessels are required to complete a logsheet for each trip, reporting the catch by species as well as other data such as the time and position of each haul. The coastal seiners also have VMS (satellite monitoring) allowing catch to be cross-referenced with the vessel track.
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The Coast Guard, who are responsible for monitoring and enforcement, collect data at the point of landing, and provide these data to IMROP.
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IMROP have enumerators (enqueteurs) at the landing sites for both coastal seiners and artisanal pirogues, who report landings by species and also collect biological data such as size-frequency, and can take samples.
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IMROP have a programme of enqueteurs visiting the fishmeal factories, to evaluate the species composition of the fish entering the freezing and fishmeal plants, and to collect biological data and samples.
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There are periodic acoustic surveys which allow for a direct estimate of biomass in the water, by species. The Mauritanian research vessel (the RV Al Awam) is currently being refitted, and is due to be replaced in the next few years under a Japanese cooperation project. The Norwegian research vessel, the RV Fridtjof Nansen, conducted regional scale acoustic surveys in autumn 2022 and autumn 2023, and will return in 2026. The Russian research vessel, the RV Atlantida, will also conduct a survey in autumn 2024. (Autumn is the most suitable season for these surveys, based on stock migrations – it is important to avoid the risk of double-counting the same fish, if they move while the survey is taking place.)
Because the stocks are shared between countries in the region, the stock assessments also includes data from neighbouring countries. The sardine stock is shared between Mauritania and Morocco, who have a similar programme of data collection, as well as national acoustic surveys twice per year (spring and autumn). The sardinella stocks are shared largely between Mauritania and Senegal who between them account for >90% of landings. Senegal, unfortunately, has had a less reliable system of data collection in recent years, but for the most recent assessments was able to provide data.
Control and enforcement is the responsibility of the Coast Guard, which is a military organisation in structure, but is administered by the Ministry of Fisheries. The Coast Guard manages the satellite monitoring system and has patrol vessels, as well as inspectors on the ground at landing sites.
With the support of the FIP, IMROP has been able to put scientific observers on board the fishing vessels for several trips. The purpose of this is to get additional data on the target species, in particular more detailed information on species composition and size-frequency. The observers also collect information about by-catch and interactions with endangered species such as cetaceans. The information so far suggests that these interactions are very rare, but the research continues.