  The Spot Prawn trap fishery off the west coast of British Columbia (BC) is
managed using a fixed escapement strategy that aims to prevent recruitment
overfishing while maximizing expected long-term yield by closing the fishery
when the catch rate of spawners, projected to the following spring, drops below
1.7 spawners per trap (the de jure rule). We develop a management strategy
evaluation framework for BC's Spot Prawn fishery that examines the expected
performance of the management procedure implemented in practice (the de facto
rule), which was significantly more conservative than the de jure rule, usually
closing the fishery when spawner catch rates were at least twice as high as
specified by the de jure rule. Simulations indicate that the de facto spawner
index rule using average empirical March 31st targets from 2000 to 2019
maintains most stocks near or above 0.8 BMSY with or without accounting for
environmental effects and/or increasing future SST on recruitment. Abundance
indices were found to be strongly hyperstable, with fishing efficiency 1.5 to
3.0 times higher under low biomass than high biomass.
