気候変動に追いつけない鳥の移動(Even birds can’t outfly climate change)

ad

2025-05-28 イェール大学

イェール大学の研究チームは、北米の406種の鳥類の20年間にわたる移動データと気温変化を分析し、気候変動に対する鳥類の適応能力を調査しました。夏季には平均で北へ約64〜80km移動し、気温上昇を約1.28℃回避しましたが、それでも元の生息地と比べて平均1.35℃の気温上昇を経験しました。冬季には移動による回避効果がさらに限定的で、平均3.7℃の気温上昇のうち、移動によって回避できたのはわずか0.5℃でした。特にカクタス・レーンなどの砂漠性種は移動せず、気候変動の影響を強く受ける可能性があります。研究者は、鳥類のような高い移動能力を持つ種でさえ、気候変動の速度に追いつけないことから、他の移動能力の低い種への影響が懸念されると指摘しています。

<関連情報>

北米の鳥類における気候変動への暴露を緩和するには、地理的再分布では不十分である Geographic redistributions are insufficient to mitigate exposure to climate change in North American birds

Jeremy M. Cohen & Walter Jetz
Nature Ecology & Evolution  Published:28 May 2025
DOI:https://doi.org/10.1038/s41559-025-02714-7

気候変動に追いつけない鳥の移動(Even birds can’t outfly climate change)

Abstract

As climate change accelerates, many species must move poleward or upslope to conserve their environmental niches and limit their exposure. While such geographic redistributions have been extensively reported, an assessment of species’ success in limiting their exposure to novel conditions is missing. Here we report on a method to account for biases in tens of millions of species observations and evaluate how 406 bird species native to the United States and Canada have mitigated their environmental niche loss using geographical redistribution. We find that most redistributions have only been partially effective at mitigating exposure to climate change. Over 20 years, species, on average, have redistributed their summertime ranges by ~0.64° north, averting their expected exposure to warming by ~1.28 °C, which is roughly half the warming they would have experienced if they had remained stationary. Meanwhile, species have only mitigated ~0.47 °C (11% of expected warming) in winter, and nearly all have experienced warming of >2 °C. Species moving the farthest north and possessing traits associated with dispersal have succeeded most in limiting their niche loss. Species’ historical niches are becoming increasingly mismatched with contemporary climates, even in a highly mobile taxon, raising concerns about the ability of other wildlife to persist in a warmer world.

生物環境工学
ad
ad
Follow
ad
タイトルとURLをコピーしました