Predicting fish stock variations on interannual to decadal time scales is one of the major issues in fisheries science and management. Although the field of marine ecological predictions is still in its infancy, it is understood that a major source of multi-year predictability resides in the ocean. Here we show the first highly skilful long-term predictions of the commercially valuable Barents Sea cod stock. The 7-year predictions are based on the propagation of ocean temperature anomalies from the subpolar North Atlantic toward the Barents Sea, and the strong co-variability between these temperature anomalies and the cod stock. Retrospective predictions for the period 1957–2017 capture well multi-year to decadal variations in cod stock biomass, with cross-validated explained variance of over 60%. For lead times longer than one year the statistical long-term predictions show more skill than operational short-term predictions used in fisheries management and lagged persistence forecasts. Our results thus demonstrate the potential for ecosystem-based fisheries management, which could enable strategic planning on longer time scales. Future predictions show a gradual decline in the cod stock towards 2024.

预测年际至十年时间尺度上的鱼类种群变化是渔业科学和管理的主要问题之一。尽管海洋生态预测领域仍处于起步阶段，但据了解，多年可预测性的主要来源在于海洋。在这里，我们首次对具有商业价值的巴伦支海鳕鱼种群进行了高度熟练的长期预测。7 年的预测是基于海洋温度异常从北大西洋副极地向巴伦支海的传播，以及这些温度异常与鳕鱼种群之间的强烈协变性。对 1957 年至 2017 年期间的回顾性预测很好地捕捉了鳕鱼种群生物量的多年至十年变化，交叉验证的解释方差超过 60%。对于超过一年的提前期，统计长期预测比渔业管理中使用的操作性短期预测和滞后持久性预测显示出更高的技巧。因此，我们的结果证明了基于生态系统的渔业管理的潜力，这可以实现更长时间尺度的战略规划。未来预测显示，到 2024 年，鳕鱼存量将逐渐下降。