Using multivariate autoregressive state‐space models to examine stock structure of Greenland halibut in the North Atlantic

Abstract Accurate information on population structure is essential for effective fisheries management. Greenland halibut ( Reinhardtius hippoglossoides ) in the North Atlantic managed as four separate offshore stocks. We use Multivariate Autoregressive State‐Space (MARSS) models to assess by means of abundance and biomass trends regions (Norwegian Sea, Iceland, Southeast Greenland, Northwest Atlantic) where three stocks are recognized: (1) Baffin Bay–Davis Strait (Northwest stock), (2) Iceland (West Nordic stock (WNS)), (3) Barents Norwegian Seas (Northeast Arctic stock). formulated model alternatives, using bottom trawl survey data from each region 1996–2019, evaluate support different structures. Abundance observations were linked growth rate parameters MARSS impact climate (North Oscillation Index) fishing (commercial catches) dynamics was investigated. Top identified an independent population. Best‐fit treated WNS two populations (east west), with potential connections between eastern western Sea. These results suggest a mismatch current perception management boundaries Northeast Atlantic.