縁の効果と,保護区内の集団の絶滅
1R. Woodroffe, Department of Zoology, Downing Street, Cambridge CB2 3EJ, UK. J. R. Ginsberg, Wildlife Conservation Society, Bronx, NY 10460-1099, USA.
Science (New York, N.Y.)
|June 26, 1998
まとめ
小さな肉食動物集団は,ランダムな遺伝的漂流によってではなく,保護区の境界にある人間の紛争によって絶滅の危機に直面しています. 人口の大きさに関係なく,幅広い種が最も脆弱であり,より広範な保全戦略の必要性を強調しています.
科学分野:
- エコロジー エコロジー エコロジー
- 保護生物学の保護生物学
- 野生生物管理とは,野生生物の管理です.
背景:
- 理論的モデルでは,人口統計的ストキャスティシティと遺伝子ドリフトにより,小さな集団が絶滅の危機に瀕していることが予測されています.
- しかし,経験的証拠は,保護区内の大型肉食動物における絶滅リスクの予測には,人口規模が不十分であることを示唆しています.
研究 の 目的:
- 保護区に生息する大型肉食動物集団における絶滅リスクの主な要因を調査する.
- 人口の大きさや人間と野生生物の衝突などの他の要因が,絶滅のより重要な予測要因であるかどうかを判断する.
主な方法:
- 保護区内の大肉食動物集団における死亡原因の分析.
- 種の生息範囲の大きさ,保護区の境界への曝露,絶滅リスクとの関連の評価.
- 保存戦略の有効性の評価は,ストキャスティックプロセスを緩和することにのみ焦点を当てました.
主要な成果:
- 保護区の国境における人間と野生生物の衝突は,死亡の主な原因として特定され,人口沈没を引き起こしています.
- より広い生息範囲を持つ種は,人口規模に関係なく,国境上の脅威に不均衡に晒され,絶滅の危険性が高くなります.
- 人間の紛争のような外部からの脅威に対処しない保全戦略は,絶滅を防ぐ可能性は低い.
結論:
- 大型肉食動物の絶滅リスクは,主に内部ストカスティックなプロセスではなく,外部の人為的要因,特に人間と野生動物の衝突によって引き起こされる.
- 保護計画では,保護区の境界にある脅威の管理を優先し,種の効果的な保護のために,種の空間的生態 (生息範囲の大きさ) を考慮する必要があります.
- 集団の大きさや遺伝的多様性だけに焦点を当てた現在の保全アプローチは,大規模な肉食動物集団を保護するのに不十分かもしれません.
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