The article discusses the sustainability of fisheries, particularly focusing on the sockeye salmon fishery in Bristol Bay, Alaska. The Bristol Bay sockeye salmon stock complex, comprising hundreds of discrete spawning populations, has maintained its productivity over the last two decades despite significant climatic changes. This resilience is attributed to the biocomplexity of the stock, which includes diverse life history traits and local adaptations to varying spawning and rearing habitats. The authors highlight that different geographic and life history components have been dominant at different times, emphasizing the importance of conserving biocomplexity for maintaining the stock's resilience to environmental changes. They also discuss the impact of climate variability, such as the Pacific Decadal Oscillation (PDO), on the productivity of sockeye salmon and the subsequent effects on the fishery. The article concludes by emphasizing the need for long-term data and fine-scale monitoring to understand and manage the biocomplexity of fish stocks, drawing lessons that apply to the conservation of other marine fish stocks.The article discusses the sustainability of fisheries, particularly focusing on the sockeye salmon fishery in Bristol Bay, Alaska. The Bristol Bay sockeye salmon stock complex, comprising hundreds of discrete spawning populations, has maintained its productivity over the last two decades despite significant climatic changes. This resilience is attributed to the biocomplexity of the stock, which includes diverse life history traits and local adaptations to varying spawning and rearing habitats. The authors highlight that different geographic and life history components have been dominant at different times, emphasizing the importance of conserving biocomplexity for maintaining the stock's resilience to environmental changes. They also discuss the impact of climate variability, such as the Pacific Decadal Oscillation (PDO), on the productivity of sockeye salmon and the subsequent effects on the fishery. The article concludes by emphasizing the need for long-term data and fine-scale monitoring to understand and manage the biocomplexity of fish stocks, drawing lessons that apply to the conservation of other marine fish stocks.