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Altered Thoreau's stomping grounds


Date: 2015-10-07; view: 600.


High-country changes

Decreased winter snowfall on mountaintops is allowing elk in northern Arizona to forage at higher elevations all winter, contributing to a decline in seasonal plants. Elk have ravaged trees such as maples and aspens, which in turn has led to a decline in songbirds that rely on these trees for habitat.


The writer Henry David Thoreau once lovingly documented nature in and around Concord, Mass. Reading those diaries today has shown researchers just how much spring has changed in the last century or so.

Compared to the late 1800s, the first flowering dates for 43 of the most common plant species in the area have moved forward an average of 10 days. Other plants have simply disappeared, including 15 species of orchids.


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Altering breeding seasons | Changing genetics
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