The shrubs probably responded first. In the 19th century, alder and flowering willows in the Alaskan Arctic stood no taller than a small child—just a little over three feet. But as temperatures warmed with fossil fuel emissions, and growing seasons lengthened, the shrubs multiplied and prospered. Today many stand over six feet.
Bigger shrubs drew moose, which rarely crossed the Brooks Range before the 20th century. Now these spindly-legged beasts lumber along Arctic river corridors, wherever the vegetation is tall enough to poke through the deep snow. They were followed by snowshoe hares, which also browse on shrubs.
Today moose and hares have become part of the subsistence diet for indigenous hunters in northern Alaska, as melting sea ice makes traditional foods like seals harder to chase.
Read the National Geographic story - “Half of All Species Are on the Move—And We're Feeling It.”