ISAME application.

More than 20 global marine extinctions and over 700 local extinctions have reportedly occurred during the past 500 years. However, available methods to determine how many of these species can be confidently declared true disappearances tend to be data-demanding, time-consuming, and not applicable to all taxonomic groups or scales of marine extinctions (global [G] and local [L]). We developed an integrated system to assess marine extinctions (ISAME) that can be applied to any taxonomic group at any geographic scale. We applied the ISAME method to 10 case studies to illustrate the possible ways in which the extinction status of marine species can be categorized as unverified, possibly extinct, or extinct. Of the 10 case studies we assessed, the ISAME method concludes that 6 should be categorized as unverified extinctions due to problems with species’ identity and lack of reliable evidence supporting their disappearance (periwinkle—Littoraria flammea [G], houting—Coregonus oxyrinchus [G], long-spined urchin—Diadema antillarum [L], smalltooth sawfish—Pristis pectinata [L], and largetooth sawfish—P. pristis [L]). In contrast, ISAME classified the Guadalupe storm-petrel (Oceanodroma macrodactyla [G]) and the lost shark (Carcharhinus obsolerus [G]) as possibly extinct because the available evidence indicates that their extinction is plausible—while the largetooth sawfish [L] and Steller’s sea cow (Hydrodamalis gigas [G]) were confirmed to be extinct. Determining whether a marine population or species is actually extinct or still extant is needed to guide conservation efforts and prevent further biodiversity losses.

据报道，过去500年间全球已有超过20种海洋物种发生全球性灭绝，700余种海洋物种在局部区域灭绝。然而，当前用于确定其中多少物种可被确凿认定为真正灭绝的方法，往往数据需求量大、耗时较长，且并非适用于所有分类群或海洋灭绝的两类尺度——全球尺度（G）与局地尺度（L）。本研究研发了一套海洋灭绝评估集成系统（Integrated System to Assess Marine Extinctions, ISAME），可适用于任意地理尺度下的任意分类群。我们将该系统应用于10个案例研究，以展示海洋物种灭绝状态可被划分为未验证、极可能灭绝以及已灭绝的三类判定路径。在本次评估的10个案例中，该系统判定其中6个属于未验证灭绝，原因在于物种鉴定存在争议，且缺乏可靠证据证实其消失，具体包括：滨螺（*Littoraria flammea* [G]）、尖吻白鲑（*Coregonus oxyrinchus* [G]）、长棘海胆（*Diadema antillarum* [L]）、小齿锯鳐（*Pristis pectinata* [L]）以及大齿锯鳐（*Pristis pristis* [L]）。与之相对，该系统将瓜达卢佩海燕（*Oceanodroma macrodactyla* [G]）与绝灭真鲨（*Carcharhinus obsolerus* [G]）归类为极可能灭绝，因现有证据表明其灭绝具有合理性；而局地尺度的大齿锯鳐与斯特拉海牛（*Hydrodamalis gigas* [G]）则被确认为已灭绝。明确海洋种群或物种究竟是已灭绝还是仍存活，可为海洋保护工作提供科学指引，并助力防止生物多样性进一步丧失。