Preliminary evaluation of two feedback management strategies for the krill fishery in Subareas 48.1–48.3

The Scientific Committee has previously used results from the Krill-Predator-Fishery Model (KPFM2, also known as Foosa) to consider the risks that implementing various management strategies for the krill fishery will compromise the Commission’s ability to achieve the objectives in Article II of the Convention. Management strategies for the krill fishery are currently comprised of an overall catch limit and a spatial distribution of this limit. We used KPFM2 to assess the risks of feedback management strategies in which the overall catch limit is dynamically redistributed among small scale management units (SSMUs) every five years based on results of monitoring either (1) the density of krill (g·m^‑2) or (2) changes in penguin abundance. Relative to the case in which the overall catch limit is statically distributed among SSMUs in proportion to catches taken during 2009-2016, we found that the two feedback management strategies we considered mostly redistributed risks to penguins and seals. Neither feedback strategy mitigated risks, beyond those projected to be incurred by the status quo distribution of fishing, in all or most SSMUs. We preliminarily attribute these results to the fact that none of the management strategies considered here redistributed fishing to offshore SSMUs, but we intend to verify this point with additional analyses. Catches by the fishery were generally projected to decrease in SSMUs where risks to predators decreased and increase where risks to predators increased, but the risks that the fishery might temporarily suspend operations due to low krill densities was insensitive to differences between the management strategies assessed. Our results suggest it may be useful to consider alternatives to the two FBM strategies evaluated here.