Hybrid total allowable catch strategy can sustain productive mixed fisheries and conserve both target and non-target species

Total allowable catches (TACs) are vital for managing fishing pressure and preventing overfishing. However, single-species TACs (SSTACs) in multispecies fisheries often lead to bycatch and choking-species issues, where fisheries close prematurely when the TAC for one species is met. Multispecies TACs (MSTACs), while potentially more effective, are rarely used due to the complexity of multispecies stock assessment. A “hybrid TAC” system, combining SSTAC for target species and MSTAC for non-target species, offers a balanced approach to conserving vulnerable species and managing overall fishing pressure. Using a size-spectrum model for multispecies, multigear fisheries in the Northern Yellow Sea, we evaluated the performance of SSTAC and MSTAC in terms of fishery production, conservation, and ecosystem health. SSTACs reduced target species yield and caused frequent choking-species issues, increasing depletion risks for non-target species. In contrast, MSTACs balanced biomass conservation with yield maintenance, reducing risks at species and community levels. These findings underscore the potential of hybrid TACs in mixed fisheries, emphasizing the need for holistic, flexible management approaches.