エコロジカルな侵食とサメとレイの絶滅リスクの拡大
Nicholas K Dulvy1, Nathan Pacoureau1,2,3, Jay H Matsushiba1
1Earth to Ocean Research Group, Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada.
Science (New York, N.Y.)
|December 5, 2024
まとめ
過剰漁獲により サメとライの個体数は1970年以降 50%減少し 絶滅の危険が高まっています 海洋生物多様性と生態系の機能を守るため,緊急の保全措置が必要である.
科学分野:
- 海洋生物学
- 保護科学
- 漁業管理
背景:
- 海洋生物多様性を評価し,過剰漁獲の影響を追跡することは,世界の指標が限られているため,困難です.
- サメとレイは海洋生態系の健康に不可欠であり,重大な脅威に直面しています.
研究 の 目的:
- 1199種のサメの絶滅リスクと生態学的機能を評価するために,50年間のレッドリストインデックスを計算する.
- 過剰漁獲がこれらの種とその生息地に与える影響を特定する.
- 人口やガバナンスなどの絶滅リスクに影響を与える要因を探る
主な方法:
- 1199種のサメとレイの絶滅リスクと生態学的機能の50年レッドリストインデックスを計算した.
- 1970年以降の人口動向とレッドリスト指数の変化を分析した.
- 絶滅の危険性は 沿岸部の人口,ガバナンス,経済,漁業補助金などの要因と相関しています
主要な成果:
- サメとライの個体数は1970年以来半分に減り 赤いリストの指数は19%も悪化しました
- 大きな種の過剰漁獲は,エコモルフォタイプの喪失と機能的多様性の5~22%の侵食を危険にさらしています.
- 絶滅の危険性は 人口が多い沿岸地域では高く, 強力な統治,経済,漁業補助金を持つ国では低い.
結論:
- 過剰漁獲はサメとレイの減少と 絶滅のリスクを高める 主な要因です
- 漁業の制限や貿易の制限を含む保全戦略は,さらなる枯渇を防ぐために不可欠です.
- これらの頂点捕食者を保護することは 海洋生物多様性,人口の接続性,そして上から下の生態学的コントロールを維持するために不可欠です.
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