国家海洋和大气管理局研究：白令海海洋热浪后雪蟹种群崩塌，雪蟹与Tanner蟹杂交蟹激增逾13倍
美国国家海洋和大气管理局（NOAA）渔业部门10月26日发布研究报告：2018至2019年白令海海洋热浪过后，雪蟹种群灾难性崩塌，其后雪蟹与 Tanner 蟹的杂交蟹数量激增至原来的13倍以上；到2025年，可捕捞规格的雄性杂交蟹占可捕雄蟹的比例已从不足10%升至41.7%。这项由 NOAA 阿拉斯加渔业科学中心 Kodiak 实验室团队完成的研究发表于《美国国家科学院院刊》（PNAS）。
研究负责人 Erin Fedewa 说：「这些结果前所未有。我们在分析2025年白令海东部底拖网调查数据时，对杂交蟹激增的幅度感到震惊。这一生态响应显然会波及渔业管理。」研究团队用动态结构方程模型检验成因后发现，升温与海冰减少并未直接促进杂交蟹或 Tanner 蟹存活，两种亲本蟹繁殖成体空间重叠增加也不是原因；真正的机制是热浪造成数十亿只雪蟹消失，竞争与捕食压力骤降，为 Tanner 蟹与杂交蟹腾出了生态空间。模型显示，源于雪蟹崩塌的这类间接效应解释了激增的76%。Tanner 蟹数量同期也升至有记录以来最高。
杂交蟹激增给渔业管理带来直接难题：雄性杂交蟹可在冬季雪蟹定向渔业中合法捕捞并作为雪蟹上岸，但因其过去极为罕见，联邦渔业管理计划从未为其单设捕捞限额。2025年，州级管理者曾为应对首波杂交蟹脉冲而上调雪蟹捕捞限额，希望渔民转而捕捞杂交蟹。研究共同作者 Emily Ryznar 表示，今年白令海东部底拖网调查中可捕规格雄性杂交蟹比2025年还多，这将持续考验决策者。
Fedewa 指出：「这是首次把杂交激增归因于一次具体的海洋热浪事件。」研究认为，海洋热浪会带来挑战既有管理框架的生态意外，渔业管理体系需要更灵活、能适应气候变化的调整机制与情景规划。
NOAA Study: After Bering Sea Marine Heatwave Collapsed Snow Crab, Snow-Tanner Hybrid Crab Surged More Than 13-Fold
NOAA Fisheries on October 26 published a study finding that after the 2018-2019 Bering Sea marine heatwave catastrophically collapsed the snow crab population, the abundance of snow-Tanner crab hybrids increased by more than 13 times; by 2025, commercial-sized male hybrids had spiked from less than 10 percent of harvestable males to 41.7 percent. The study, by scientists at the Alaska Fisheries Science Center's Kodiak Laboratory, was published in the Proceedings of the National Academy of Sciences (PNAS).
"These results are unprecedented," said study lead Erin Fedewa. "We were shocked by the magnitude of the hybrid surge while analyzing data from the 2025 eastern Bering Sea bottom trawl survey. It immediately became clear that this ecological response would ripple through to fisheries management." Using dynamic structural equation models, the team found that warmer waters and reduced sea ice did not directly boost hybrid or Tanner crab survival, and that the surge was not driven by increased spatial overlap between breeding adult snow and Tanner crabs. Instead, the loss of billions of snow crabs after the heatwave released hybrids and Tanner crabs from competition and predation; the modeling attributed 76 percent of the surge to these indirect effects of the snow crab collapse. Tanner crab abundance also reached its highest level on record in 2025.
The surge poses an immediate management dilemma: male hybrids can be legally harvested and landed as snow crab during the directed winter fishery, yet because hybrids were historically so rare, the federal fishery management plan never set hybrid-specific harvest limits. In 2025, state managers responded to the initial hybrid pulse by increasing the snow crab harvest limit in hopes that fishermen would target and land hybrids. Co-author Emily Ryznar said this year's eastern Bering Sea bottom trawl survey found even more commercial-sized male hybrids than in 2025, making this a continuing challenge for decision makers.
"This study marks the first time an increase in hybridization has been attributed to a discrete marine heatwave event," Fedewa said. The researchers conclude that marine heatwaves can produce ecological surprises that challenge rigid management frameworks, and that more flexible, climate-adaptive management and scenario planning will be critical.
来源：GSM·美国（原文链接）
图片来源：图：2026年白令海东部底拖网调查采集的雪蟹与Tanner蟹杂交蟹特写，其弯曲的口部为区别于亲本物种的中间形态特征。图片：美国国家海洋和大气管理局 NOAA Fisheries / Leah Zacher（公共领域）。Photo: Close-up of a snow-Tanner hybrid crab collected during the 2026 eastern Bering Sea bottom trawl survey, showing its curved mouth. Image: NOAA Fisheries / Leah Zacher (public domain).
