The Commonwealth HSP requires that stocks be maintained, on average, at a biomass level that produces maximum economic yield (BMEY). In multispecies fisheries, this has been interpreted to be the combination of species biomasses that maximise economic profits for the fishery overall, which may differ substantially from what may be derived in a single species assessment. The HSP requires a set of target reference points for each species consistent with the principle of maximising economic returns from the fishery as a whole to be established. The existence of non-target by-product species affects the optimal yield of the target species (and vice versa), and subsequently their appropriate reference points. There is currently no standard framework to determine target reference points for individual stocks within a multispecies fishery to generate MEY for the fishery as a whole. Simple single species indicators such as the 1.2 BMSY proxy for BMEY may not always be accurate. Similarly, use of reference CPUE rates in cases where data on species are poor is also inappropriate, and is proving problematic. For example, in the SESSF, problems have recently arisen regarding the proposed quotas for Ocean Perch (a by-product species) being incompatible with those for their associated target species (Pink Ling).

The aim of this project is to develop and demonstrate a framework that will assist managers in developing target reference points consistent with the HSP in multispecies fisheries. The project will address both target species and non-target species simultaneously, and will consider indicators for both data rich and data poor species.