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Northern shrimp (Pandalus borealis) represents one of the most important fisheries in the Northwest Atlantic Ocean, but few studies have considered connectivity among different management units (i.e., stocks). Using a biophysical model, we investigated potential larval dispersal among North Atlantic Fisheries Organization (NAFO) divisions and its interannual variability during the long pelagic larval phase of P. borealis (~3 months). Overall, we found a largely stable, stream-like larval connectivity system driven by the main currents that flow over both the Greenland and Canadian continental shelves, with a relatively low but consistent exchange of larvae between Greenland and Canada across the Baffin Island continental shelf. We observed highest potential settlement densities on the northwestern Greenland and Newfoundland shelves, representing retention areas that correspond to highest abundances of adult shrimp. Intermittent and variable larval exchanges of lower magnitude also occurred between populations less obviously associated with the major circulation features. Our study improves understanding of northern shrimp stock-recruitment relationships at the metapopulation level, which could help determine the appropriate spatial scale to improve management strategies. Si la peche a la crevette nordique (Pandalus borealis) est une des peches les plus importantes dans le nord-ouest de l'ocean Atlantique, peu d'etudes ont examine la connectivity entre differentes unites de gestion (c.-a-d. stocks). A l'aide d'un modele biophysique, nous avons examine la dispersion potentielle de larves entre les divisions de l'Organisation des peches de l'Atlantique Nord-Ouest (OPANO) et sa variability interannuelle durant la longue etape de larve pelagique de P. borealis (~3 mois). De faqon generale, nous avons releve un systeme stable de connectivite des larves s'apparentant a des flux oceaniques modules par les principaux courants qui parcourent les plateaux continentaux groenlandais et canadiens, et des echanges de larves assez faibles, bien que stables, entre le Groenland et le Canada a travers le plateau continental, de la terre de Baffin. Nous avons observe les plus grandes densites d'etablissement potentielles sur les plateaux du nord-ouest du Groenland et de Terre-Neuve, representant des zones de retention qui correspondent aux plus fortes abondances de crevettes adultes. Des echanges de larves intermittents et variables de moins grande ampleur ont aussi ete observes entre des populations dont l'association aux courants marins majeurs est moins evidente. L'etude ameliore la comprehension des relations entre le recrutement et les stocks de crevette nordique a l'echelle de la metapopulation, ce qui pourrait aider a etablir la bonne echelle spatiale pour ameliorer les strategies de gestion. [Traduit par la Redaction], Introduction Northern shrimp (Pandalus borealis) represents one of the most important fisheries in the Northwest Atlantic Ocean (third highest value in Canada in 2018; DFO 2019a) and the most important [...]

Abstract: The recommendation of mid-ocean exchange of ballast water has resulted in significant release of aquatic invasive species in shelf areas. This paper describes a semiquantitative risk assessment model developed [...]