過剰搾取の経済学が再考された
R Q Grafton1, T Kompas, R W Hilborn
1Crawford School, Australian National University, Ellery Crescent, Canberra, ACT 0200, Australia. quentin.grafton@anu.edu.au
まとめ
漁業の経済的収量 (MEY) を最大化することで,魚の蓄積を再構築することができ,より大きな利益につながる. このアプローチは,世界の漁業管理における保全と経済的利益の双方のシナリオを提供する.
科学分野:
- 漁業 科学 漁業 科学
- 海洋生態学 海洋生態学
- 保護生物学の保護生物学
背景:
- 世界の漁業の約25%が過剰に利用され,生物質は最大持続可能な収量 (MSY) のレベルを下回っています.
- 伝統的な漁業管理は,MSYに焦点を当てていることが多いが,MSYは経済的収益性とは一致しない.
研究 の 目的:
- 経済的収量 (MEY) を最大化することで,魚のバイオマスの増加につながるかどうかを調査する.
- 漁業の保全と経済的利益のためのツールとしてのMEYの可能性を評価する.
主な方法:
- 4つの異なる漁業に新しい方法を適用し,オレンジ・ラフイのような長寿種を含む漁業を対象とした.
- 計算されたダイナミックMEY,値下げ経済利益を最大化するバイオマスレベル.
主要な成果:
- 調査された漁業では,ダイナミックなMEYがMSYを上回ることが判明しました.
- 合理的な割引率と現在の経済条件の下で,より大きな魚の蓄積は,経済的利益を増やすことが示されました.
結論:
- MEYを達成することは,魚の蓄積量と経済的利益の両方を高め,双赢の戦略である可能性があります.
- MSYを超えるMEY目標を設定し,漁業者に移行コストを補償するメカニズムを導入することで,資源の再構築に対する反対を克服し,過剰搾取を減らすことができます.
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