大規模で広く分布する魚の絶滅の危機に瀕している
1J. M. Casey, Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 5S7. R. A. Myers, Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J1.
まとめ
海洋脊椎動物の絶滅は過小評価されているかもしれない. 長期調査によると,西北大西洋のバーンドア・スケート (Raja laevis) は絶滅寸前であり,ここ数十年で捕獲はゼロとなっている.
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
- 保護生物学の保護生物学
背景:
- 海洋脊椎動物の絶滅は,しばしば珍しいと考えられています.
- 多くの種の長期の人口動向に関するデータは限られている.
- スケートは,様々な人為的な圧力に直面している軟骨魚です.
研究 の 目的:
- 北西大西洋におけるバーンドアスケート (Raja laevis) の絶滅リスクを評価する.
- 海洋脊椎動物における現在の絶滅率のデータの正確性を評価する.
- 重要なスケート種の長期の集団変化を記録する.
主な方法:
- 漁業に関する長期的な独立研究調査データの分析.
- 数十年 (45年) にわたる漁獲率の比較.
- 種分布と繁殖範囲における種の分布と繁殖量の評価.
主要な成果:
- バーンドア・スケート (Raja laevis) の個体数は急激に減少しています.
- かつて一般的であった (45年前は牽引船の10%),近年の調査 (過去20年間) では,バーンドアスケートは捕えられなかった.
- 種の範囲全体で同様の減少が観察されています.
結論:
- バーンドア・スケート (Raja laevis) は絶滅危惧種で,絶滅の危機に瀕しています.
- 現在のデータは,海洋脊椎動物の絶滅率を大幅に過小評価している可能性があります.
- この種と,潜在的に他の種のために緊急の保全措置が必要である.
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