The current HSP has biomass target reference points. The problem however, is that research has shown that in multi-species fisheries with technical interactions (i.e. the mixture of different species catches with the same gear) and ecosystem interactions (e.g. competition or predation), it is not possible to maintain all species at the same target level, and there is no empirical basis to assume biomass of non-target species will always be below or at BMEY. In fact, it is likely that the biomass of some of these species will be greater than BMEY as well as below it. This was demonstrated for the SESSF by Smith et al (2107).

The new CHSP recognises that net economic returns for multi-species fisheries may be maximised by including differential targets in harvest strategies that are always above BLIM, but greater or lower than BMEY. In addition, recent recommendations by the SESSF Monitoring and Assessment Research Project (SMARP) into monitoring and assessment options, including multi-year TAC decision frameworks, require simulation testing. Thus, there is a critical need to develop, evaluate and operationalise a fishery-wide harvest strategy with multiple and appropriate reference points, and multispecies decision rules. The question is what would a multi-species harvest strategy that covers an entire fishery or component of it, rather than a number of single species harvest strategies, look like.

We need to develop and operationalise a fishery-wide harvest strategy with multiple and appropriate reference points, and multispecies decision rules.

This will need to be implemented by June 2020, so there is an urgent need to design and evaluate a range of options from which to select a candidate harvest strategy. The aim of this project is to develop a fit-for-purpose harvest strategy in the SESSF that meets the intent of the policy, is cost effective and maximises net economic returns.