荒涼とした原野に、やせ細って疲れ切ったホッキョクグマが倒れ込んでいる。食料となるアザラシがいる海氷を探し求めるうちに、衰弱し、死に至ったのだ、と科学者は説明している。
このホッキョクグマは、エサ場となる海氷を求めて何百キロメートルも歩いてきた。しかし、ついに食料を見つけることができなかったのだ。
ホッキョクグマを研究するイアン・スターリング氏がこの亡骸を発見したのは、スヴァールバル諸島の北部。研究のために北極圏を船でまわっている最中だった。
「ガーディアン」の記事によれば、このホッキョクグマは、わずか数カ月前の今年4月に、スヴァールバル諸島の南部で確認されており、そのときには健康だったという。死亡していた場所は、通常の生息範囲をかなり超えた場所だった。
ホッキョクグマたちの前途は厳しい。気候変動の影響によって、北極圏の氷が約40年以内に消える可能性がある、と科学者らは警告しているのだ。
スターリング氏は、海氷の減少によって、スヴァールバル諸島の動植物は生活基盤を失いつつあると説明している。
「北極では1990年代末以降、200万平方キロメートルを超える広さの海氷が失われている。これは、莫大な生息環境が奪われていることを示している」
「（北極圏に生息する）生命を支えるすべてのものが失われつつあるのだ」という同氏の発言を、カナダの『Ottawa Citizen』紙は伝えている。
北極圏の氷が1970年代から現在まで減少を続けており、北極点が、氷原ではない湖になる時も多いことを紹介する日本語版記事はこちら。なお、スヴァールバル諸島の気温は100年間で摂氏6度、最近30年間では4度上昇している。
[Jacqueline Head (English) 日本語版：遠藤康子、合原弘子/ガリレオ]
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気候変動で失われるかもしれないもの
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