The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes—sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first global marine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators.

国际自然保护联盟 (IUCN) 红色名录评估过程正在揭示海洋生物多样性丧失的规模和驱动因素。我们首次对 1,199 种软骨鱼类——鲨鱼、鳐鱼和嵌合体——进行了全球重新评估。第一次全球评估（2014 年）得出结论，四分之一（24%）的物种受到威胁。现在，391 (32.6%) 个物种面临灭绝的威胁。当这一威胁百分比应用于数据缺乏物种时，估计超过三分之一（37.5%）的软骨鱼类受到威胁，其中大部分变化来自新信息。三个物种极度濒危（可能已经灭绝），这可能代表了由于过度捕捞而导致的第一次全球海洋鱼类灭绝。最后，软骨鱼类的灭绝率可能是每百万物种年有 25 次灭绝，与陆生脊椎动物相当。过度捕捞是影响所有 391 种受威胁物种的普遍威胁，是 67.3% 物种的唯一威胁，并与其余三分之一的其他三种威胁相互作用：栖息地的丧失和退化（受威胁物种的 31.2%）、气候变化（10.2%）和污染（6.9%）。物种在热带和亚热带沿海水域受到不成比例的威胁。迫切需要基于科学的捕捞限制、有效的海洋保护区以及降低或消除捕捞死亡率的方法，以尽量减少受威胁物种的死亡率并确保其他物种的可持续捕捞和贸易。