獲物を切り離すことは,捕食者の回復を促進します - 全湖実験における代替状態です
Lennart Persson1, Per-Arne Amundsen, André M De Roos
1Department of Ecology and Environmental Science, Umeå University, S-901 87 Umeå, Sweden. lennart.persson@emg.umu.se
Science (New York, N.Y.)
|June 26, 2007
まとめ
古い獲物魚を殺害することで,湖のトップ捕食者集団を回復させることができます. この生態管理戦略は,小型の獲物を増やすことで,捕食者の回復を助け,生態系の安定性を15年以上維持します.
科学分野:
- エコロジー エコロジー エコロジー
- 漁業 科学 漁業 科学
- 保護生物学の保護生物学
背景:
- トップの捕食動物である魚の個体数は,過剰漁獲により,地球規模で崩壊し,生態系の状態が変化しています.
- いくつかの生態系の変化は不可逆的であり,生態系の回復と漁業管理に重大な課題をもたらす.
研究 の 目的:
- 獲物魚の断絶がトップ捕食者の魚群の回復を促進できるかどうかを調査する.
- 実験的操作を通じた大規模なフィールドシステムにおける代替的な安定状態を実証する.
主な方法:
- 大規模で低生産性の湖で捕食魚種の古い,衰弱した個体を取り除く実験.
- 屠殺後の獲物の利用可能性と捕食者集団の動態の変化を監視する.
主要な成果:
- 古い獲物魚の除去により,より小さな獲物個体の利用が増加しました.
- この獲物の増加は,トップ捕食者の魚群の回復を容易にした.
- 改変されたコミュニティ状態は,介入終了後15年以上も安定したままでした.
結論:
- 特定の獲物魚を殺害することは,崩壊したトップ捕食者の魚群の回復のための効果的な,直感に反する戦略である可能性があります.
- 食物に依存する獲物の成長ダイナミクスは,自然界に共通している可能性のある代替的な安定状態へのシフトを促す可能性があります.
- 生態管理戦略は,これらの代替的な安定状態を考慮し,新しい介入を採用する必要があるかもしれません.
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