Description and use of parameters within Antarctic krill (Euphausia superba) assessment models conducted with the Grym

Summary

The Commission for the Conservation of Antarctic Marine Living Resources has recently decided to re-adopt the generalised yield model (GYM) as an assessment tool to progress the management of Antarctic krill (Euphausia superba). To this end, the GYM has been re-implemented in the open source R package Grym. This document describes the model parameters required to conduct a krill stock assessment with Grym and, where possible, provide guidance as to how these parameters can be estimated.