URUGUAY - Understanding spatial structure and connectivity of meta-population fish stocks is highly important when assessing the sustainability of fisheries, according to new research from the Universidad de la República Oriental del Uruguay, supported by the Marine Stewardship Council (MSC).
Unlike many self-sustaining ‘closed’ populations, meta-populations are interconnected networks encompassing a number of distinct sub-populations that rely on the dispersal of larvae or the immigration of adult fish from neighbouring areas to sustain their numbers.
In a comprehensive review of meta-population fisheries published in the MSC's Science Series, researchers explained that without understanding of the locations of sub-populations as well as the oceanographic processes that connect them, fisheries assessments could be inaccurate, potentially leading to inappropriate management or a higher risk of overexploitation.
The authors also provided technical guidance upon which to base assessments of meta-population fisheries.
Dr Omar Defeo, lead author of the paper said: “Although the application of the meta-population in fishery assessments is not a new concept, in many situations, little is known about the stock connectivity among them.
"This is especially a challenge in data-poor fisheries in developing countries. Knowledge sharing and research should be encouraged to further develop solutions to allow long-term success in managing meta-population fisheries.”
In marine environments, sessile invertebrates such as scallops, lobsters and mussels often live in meta-populations, along with some species of fish (e.g. salmon, herring, mackerel).
The authors note that in the Georges Bank scallop fishery, one sub-population of scallops could provide up to 80 per cent of the region’s egg production, demonstrating the importance of identifying critical sub-populations.
In another featured paper, 'Best practices for managing, measuring and mitigating the benthic impacts of fishing', Chris Grieve et al. review best practice in fisheries management when harvesting resources that come into contact with the sea floor.
The authors recognised the complexity of monitoring, measuring and mitigating impacts on benthic habitats, and emphasised that management at multiple levels with involvement from governments, resources users and other stakeholders are critical to ensure sustainable outcomes.
Both reports provided the MSC with evidence to guide a recent review of its Fisheries Standard.
You can view the Science Series publication by clicking here.
TheFishSite News Desk