肉食魚のコミュニティが世界中で急速に枯渇しています
1Biology Department, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J1. Ransom.Myers@dal.ca
Nature
|May 16, 2003
まとめ
産業化された漁業は,大規模な捕食魚のバイオマスを15年以内に80%大幅に削減しました. 今日,世界の魚のバイオマスは,工業化以前の水準のわずか10%であり,海洋生態系に影響を与えています.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 漁業 科学 漁業 科学
- エコロジー エコロジー エコロジー
背景:
- 産業化された漁業は生態学的懸念を引き起こし,漁業の回復のための世界的なイニシアチブを促した.
- 未開発の魚群の理解は,効果的な海洋生態系の回復に不可欠です.
- 保存のためのベースラインを確立するために,魚の個体数に関する歴史的データは不可欠です.
研究 の 目的:
- 歴史的なコミュニティバイオマスと大型捕食魚の組成を再構築する.
- 工業化以前の魚群と現代の魚群を比較する.
- 海洋生態系回復の取り組みのベースラインを提供すること.
主な方法:
- 大陸棚と海洋システムからの歴史的な漁業データの分析.
- 採掘の開始からコミュニティのバイオマスと組成の軌跡の構築.
- 工業化以前のレベルと比較して現在の魚のバイオマスを推定するためのメタ分析的アプローチ.
主要な成果:
- 産業漁業は,コミュニティのバイオマスを15年以内に約80%削減しました.
- 急速に成長する種は当初増加したが,減少はしばしば逆転した.
- 現在の大型捕食魚のバイオマスは,工業化以前の水準のわずか10%であると推定されています.
結論:
- 大規模な捕食者の減少は,重要な生態学的影響を持つ世界的な現象となっています.
- 最近のデータにのみ依存する管理戦略は,効果的な回復のために不十分である可能性があります.
- この研究は,回復目標に不可欠な未開拓の魚群の重要なベースラインの見積もりを提供します.
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