Updated 2020 Tristan da Cunha rock lobster assessment

This paper provides details of an updated 2020 assessment of the rock lobster resource at the island of Tristan da Cunha, which takes account of the most recent data available. This assessment takes explicit account of the separate data available from the powerboats, the Edinburgh/Geo Searcher and the annual biomass survey. Results are similar to previous assessments, but indicate that the decline in abundance since ~2006 has come to an end with increases in exploitable and spawning biomass over the 2015+ period, although the exploitable biomass is estimated to have declined slightly over the last two seasons. Current spawning biomass relative to pristine is estimated to be 75%. Results presented are for rescaled standardised CPUE which take recent fishing efficiency changes into account.