"Rising temperatures have spurred an influx of beavers to Alaska and northern Canada ‘on a huge scale’".
"The stream through western Alaska never looked like this before. In aerial photography from the 1980s, it wove cleanly through the tundra, thin as thread. Today, in satellite images, it appears as a string of black patches: one large pond after another, dozens of metres apart.
It’s a transformation that is happening across the Arctic, the result of landscape engineering on an impressive scale. But this is no human endeavour to reshape the world. It is the work of the North American beaver, and there is no sign of it stopping.
Were the waddling rodents making minor inroads, researchers may never have noticed. But the animals are pouring in, pushing north into new territories. The total number of animals is far from clear, but the ponds they create are hard to miss: in the Arctic tundra of Alaska alone, the number of beaver ponds on streams have doubled to at least 12,000 in the past 20 years. More lodges are dotted along lakes and river banks."
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