Twice each year, the snowshoe hare undergoes a change in its fur color; it turns brown in the spring, and white in fall. It's a crucial characteristic that helps camouflage snowshoe hares from predators, and as NPR points out, the small rabbits have to contend with many of them. But climate change is throwing a wrench into the rhythm. As warm weather stretches longer and longer, the hares are increasingly shifting color too soon, defeating the purpose of their natural defense and making them stand out like a sore thumb to would-be attackers. Alex Kumar, a graduate student at the University of Montana, has been studying the "mismatch" phenomenon.
"If the hares are consistently molting at the same time, year after year, and the snowfall comes later and melts earlier, there's going to be more and more times when hares are mismatched," he told NPR. Unsurprisingly, research shows that mismatched snowshoe hares are dying at a faster rate. And while these rabbits won't be vanishing anytime soon, the situation could present a crisis for animals like the Canada lynx that count snowshoe hares as a crucial food source. There are some signs that the hares may eventually be able to adapt and keep pace with the effects of climate change, but nothing definitive. "What we don't know very well is how fast is too fast," says Scott Mills of North Carolina State University, who's heading up the research.