Policies aiming to restore ecosystems, achieve thriving fisheries and reverse biodiversity loss require knowledge of their former status and long‐term variation. As quantitative fish data is typically only available for recent decades long after changes may have occurred, a greater use of qualitative sources has been encouraged in marine historical ecology. We examined diverse historical information (including maritime history, fisheries reports, naturalists' accounts, recipes, nautical charts and newspapers) across a multi‐century time span (13th–20th century) for a wide range of species to document their long‐term trajectories in an understudied Northeast Atlantic ecosystem (Irish Sea coast of Wales). We find strong evidence of the loss of both a pelagic fishery for herring, which was of fundamental socio‐ecological importance since at least the 13th century, and the loss of significant multi‐species demersal and intertidal fisheries. Local, commercial and/or functional extinction has occurred for taxa spanning a wide range of diversity (crustacean, elasmobranchs, sturgeon, and teleosts), body size and ecological role, suggesting far‐reaching changes to food webs. This raises fundamental questions about the present‐day health and integrity of this coastal ecosystem and the long‐term viability of current fisheries which depend on a few shellfish species. Our century‐scale synthesis of qualitative data for multiple taxa allows the collective breadth of losses to be fully appreciated and may reduce the risk of ‘shifting baselines’. Restoration to historical baselines may not be achievable, but our findings provide evidence of long‐term change relevant to policies for recovery, and prevention of further decline of fishes, fisheries and ecosystems.

中文翻译：

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定性历史资料揭示温带海洋生态系统鱼类和渔业的世纪规模损失和变化


旨在恢复生态系统、实现渔业繁荣和扭转生物多样性丧失的政策需要了解其以前的状况和长期变化。由于定量鱼类数据通常只能在发生变化后很长时间才能获得，因此海洋历史生态学鼓励更多地使用定性来源。我们研究了多个世纪时间跨度（13 至 20 世纪）的各种历史信息（包括海洋历史、渔业报告、博物学家的叙述、食谱、海图和报纸），记录了各种物种的长期轨迹位于尚未得到充分研究的东北大西洋生态系统（威尔士爱尔兰海沿岸）。我们发现有力的证据表明，至少从 13 世纪以来，远洋鲱鱼渔业就具有重要的社会生态重要性，而且大量的多物种底层和潮间带渔业也已消失。范围广泛的多样性（甲壳类、板鳃类、鲟鱼和硬骨鱼）、体型和生态作用的类群都发生了局部性、商业性和/或功能性灭绝，这表明食物网发生了深远的变化。这引发了关于该沿海生态系统目前的健康和完整性以及依赖于少数贝类物种的当前渔业的长期生存能力的基本问题。我们对多个分类群的定性数据进行了百年规模的综合，使损失的集体范围得到充分认识，并可能降低“基线转移”的风险。恢复到历史基线可能无法实现，但我们的研究结果提供了与恢复政策相关的长期变化的证据，以及防止鱼类、渔业和生态系统进一步衰退。