Bridge-building between the 2017 and 2018 hake RC assessment models

Abstract

This document builds on FISHERIES/2018/MAY/SWG-DEM/20, which summarised changes made to the hake Reference Case (RC) assessment model over the period from May 2017 to May 2018. Following the tabling of DEM/20, one further update has been made to the RC model, namely that CPUE and catch data based on species splitting algorithm Model A6b (instead of Model A6) are now being used for the RC. However, rather than re-run all the bridge-building models, the results from DEM/20 have been retained and thus compare the various “snapshots” with the RC model at that time (i.e. May 2018). Results for the most recent (July 2018) RC model using the model A6b data have been included in the tables, but not the figures, in the interests of time, given that what is more important here is to indicate impacts in relative (not necessarily absolute) terms. Note further that during the course of the workshop it became apparent that the information provided in Appendix A was not complete; hence this document has been revised to address this, with further information provided in Appendix A, and an Appendix C is now added with information from one of the workshop working papers.