本篇為劉教授與其所屬的國際自然保育聯盟(IUCN)鯊魚專家群以生命地球指數及紅色名錄指數針對全球半世紀以來31種表層鯊魚及魟進行資源下降評估，結果發表於1月28日最新一期全球最具權威的期刊Nature。此研究結果顯示自1970年以來，由於漁獲壓力增加了18倍，這些物種資源減少了71%，且3/4的標誌性物種有滅絕風險。嚴格執行禁捕或基於科學的預警式漁獲量管制，將可避免資源的崩潰。此篇蒐集目前最完整的生物學及漁業相關文獻及資料，同時也參考過去區域性漁業組織進行資源評估的結果，進行分析，所得到的結果極具學術價值，也對全球表層鯊魚及魟資源管理與保育有極大貢獻。

劉光明教授與其國際研究團隊，照片來源：2018 IUCN Pelagic Sharks Red List Assessment. Meeting Group Photo

劉教授目前為海洋事務與資源研究所所長及鯊魚永續研究中心主任。

期刊摘要：

Nathan Pacoureau*, Cassandra L. Rigby, Peter M. Kyne, Richard B. Sherley*, Henning Winker, John K. Carlson, Sonja V. Fordham, Rodrigo P. Barreto, Daniel Fernando, Malcolm P. Francis, Rima W. Jabado, Katelyn B. Herman, Kwang-Ming Liu, Andrea D. Marshall, Riley A. Pollom, Evgeny V. Romanov, Colin A. Simpfendorfer, Jamie S. Yin, Holly K. Kindsvater and Nicholas K. Dulvy. (2021). Half a century of decline in oceanic pelagic sharks and rays. Nature 589 (7843): . (IF:42.779, ranking 2019: 1/71 in Multidisciplinary Sciences)

Summary: Overfishing is the primary cause of marine defaunation, yet individual species declines and rising extinction risk are difficult to measure, particularly for the largest predators found in the high seas. We calculate two well-established indicators to track progress towards Aichi Biodiversity Targets and Sustainable Development Goals, the Living Planet Index (a measure of changes in abundance aggregating 57 abundance time-series for 18 oceanic shark and ray species), and the Red List Index (a measure of extinction risk calculated for all 31 oceanic shark and ray species). We find that, since 1970, the global abundance of oceanic sharks and rays has declined by 71% due to an 18-fold increase in Relative Fishing Pressure. This depletion elevated global extinction risk to the point where three-quarters of this functionally important assemblage of iconic fishes are now considered threatened with extinction. Strict prohibitions and precautionary science-based catch limits are urgently needed to avert population collapse, avoid disruption of ecological function, and promote species recovery.

全球表層鯊魚及魟資源下降量評估，圖片來源：Pacoureau et al. (2021)