Working Group on Commercial Catches (WGCATCH)

WGCATCH contributes to ensure the quality of commercial catch data, which underpins stock assessments and advice. At this year’s WGCATCH meeting all the proposed ToRs were covered and objectives were met. The group started documenting the national estimation procedures (Section 3.2). Most of the countries use ratio estimators for their estimation. Recent discussions at WGCATCH and other EGs have increasingly highlighted that estimation techniques currently used by many countries to process commercial catch data may not be the most up-to-date and/or ignore sampling design and/or are far from transparent and/or involve significant levels of adhoc decisions. Therefore, WGCATCH recommends a series of practical workshops on estimation procedures for the next 3 years to produce best practice guidelines for choosing methods and variables used to raise commercial sampling data. Under ToR a.3, the sample size thresholds used for national data provision were documented. WGCATCH discussed extensively use of specific thresholds, however, it is not possible to come up with a single universal rule to be applied across all countries and stocks. Instead, WGCATCH advises that specific analytical steps are taken during the benchmark process to test and evaluate the impacts of applying or not thresholds to national data before providing the data to the assessment. Intersessional work was carried out to develop tools to be used by the data submitters and stock coordinators to understand and summarise the quality and quantity of the data provided to Intercatch (Section 3.3). The work developed under SSF, ToR b), continued to develop best practice guidelines on SSF data collection, with quantitative analyses on the coverage/completeness of fishing activity. PCA analysis was carried out of data incompleteness issue or over-declaration to build a risk’ map where each country*area is positioned (Section 4.2). The sub-group reviewed the proposed CL and CE data formats from RDBES cor