ICES | WK6ACODID; OUTPUTS FROM 2021 MEETING 2022 | iii ii Expert group information Expert group name Workshop on stock identification of West of Scotland cod (WK6aCodID) Expert group cycle Annual Year cycle started 2021 Reporting year in cycle 1/1 Chair(s) Carl O’Brien, United Kingdom Meeting venue(s) and dates 29 November – 1 December 2021, online meeting (16 participants) ICES | WK6aCodID; outputs from 2021 meeting 2022 | 1 1 Introduction 1.1 Terms of reference (ToRs) A Workshop on Stock Identification of West of Scotland Sea Cod (WK6aCodID) chaired by Carl O’Brien, UK, will meet online from 29 November – 1 December 2021 to: a) Review information on stock identification of West of Scotland cod and adjacent areas in the context of the Atlantic cod population structure, including critical evaluation of inferences from each source of information, to build up a picture of cod sub-stock structure in the West of Scotland and adjacent areas, based on the following: i) Distribution and movements of different life-stages of cod, including changes over time, inferred from: 1) Tagging 2) Scientific Surveys 3) Commercial landings 4) Dispersal models (e.g. of cod eggs and larva/juveniles) ii) Genetic analyses iii) Otolith microchemistry iv) Morphometrics and meristics v) Life-history and parasites vi) Other approaches not listed above b) Based on the evidence from ToR a), formulate scenarios for cod stocks West of Scotland and adjacent areas, and assess the evidence-based plausibility of each of these scenarios (includ- ing current definitions). c) Consider the practical implications, for data, particularly historical time-series of catch data, of each of the scenarios in ToR b), and how any difficulties might be dealt with.