The American pika, a small flower-gathering relative of the rabbit, may be one of the first mammals in North America known to fall victim to global warming if heat-trapping emissions are not reduced soon. American pikas are typically found in rocky areas, called talus, within alpine regions of the western United States and southwestern Canada. Many hikers, while passing through pika habitat in these rocky areas, have heard these shy creatures call and whistle to each other.
Since food is difficult to obtain in winter in the alpine environment, pikas cut, sun-dry, and later store vegetation for winter use in characteristic 'hay piles.' They are often called 'ecosystem engineers' because of their extensive haying activities.
According to research, global warming appears to have contributed to local extinctions of pika populations. American pikas may be the 'canary in the coal mine' when it comes to the response of alpine and mountain systems to global warming.
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