象牙のくちばし鳥 (Campephilus principalis) は北米大陸に生息しています
John W Fitzpatrick1, Martjan Lammertink, M David Luneau
1Cornell Laboratory of Ornithology, Cornell University, 159 Sapsucker Woods Road, Ithaca, NY 14850, USA. jwf7@cornell.edu
Science (New York, N.Y.)
|April 30, 2005
まとめ
かつて絶滅したと考えられていた象牙くちばし鳥 (Campephilus principalis) が,アーカンソー州で再発見されました. 証拠には,視覚的な目撃,ビデオ分析,そして音響シグネチャーが含まれ,生き残った集団を示唆しています.
科学分野:
- 鳥類学 鳥類学とは,鳥類学である.
- 野生生物保護 野生生物保護
- 生物多様性研究 生物多様性研究
背景:
- 象牙のくちばし鳥 (Campephilus principalis) は,絶滅が広く疑われ,保護上の懸念のある種である.
- 歴史的記録は,この種が米国南東部に住んでいたことを示していますが,近年,この種の目撃は極めて稀でした.
研究 の 目的:
- 象牙のくちばしのオオカミの継続的な存在を確認するために.
- 特定の地理的地域における種の証拠を文書化するために.
主な方法:
- アーカンソー州東部のビッグ・ウッズ地域での視覚調査と観測記録を行う.
- 2004年4月に撮影されたビデオ映像を分析して,この種の存在を明らかにした.
- カンペフィルス (Campephilus) のオオカミと関連した音響シグネチャ,特にディスプレイドラムの検出と分析.
主要な成果:
- 2004年と2005年の間,少なくとも1匹のオスの象牙ビック・ウッドペッカーとの視線接触が確認されています.
- ビデオ証拠の分析により,鳥の存在が確認された.
- 音響モニタリングにより,象牙のくちばしで飾られたのディスプレイドラムと一致する音のパターンが検出されました.
結論:
- ビッグ・ウッズで象牙のくちばしで木の再発見は,その絶滅に反対する重要な証拠を提供します.
- 集団は薄く分布しているように見えますが,広大な潜在的な生息地は,小規模ではあるが,生存可能な繁殖集団が存続することを示唆しています.
- この再発見された集団の完全な規模と状態を決定するために,さらなる広範な調査が必要である.
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