Review of the assessment framework for Atlantic Cod in NAFO 3Pn4RS : population modelling and elements relevant to a renewed precautionary approach and rebuilding plan

Abstract

Fisheries and Oceans Canada in the Quebec region undertook in 2021-2022 a review of the assessment framework for the Northwest Atlantic Fisheries Organization (NAFO) 3Pn4RS Atlantic cod (Gadus morhua) stock in the northern Gulf of St. Lawrence. A review of assessment inputs, including information on reported and non-reported fishery catches, tagging information and fishery independent monitoring results took place in the spring of 2021. The present document supports the second part of the framework review, which took place in May 2022. That meeting examined some additional assessment model inputs and modelling considerations and principally examined a proposed new model for the assessment of the 3Pn4RS cod stock. The current research document presents the details of that new model and associated model results, as well as results for alternative model formulations, some limited simulation tests and sensitivity evaluations for key model assumptions. We also present methodology for model projections and discuss key uncertainties related to projections of future stock status, particularly as they relate to longer term projections required as part of rebuilding planning. Finally, we review the information available at the time to define revised reference points for the management of the stock and to support the development of a new rebuilding plan for the stock.