Despite what you may think, New York City's rats do not subsist entirely on pizza crusts and abandoned street meat, so when snow blankets the ground and regular food sources like seeds and grass are covered up it can get harder for a rat to find something to eat.
In New York, says Stephen Nessen for WNYC, this past winter's freezing temperatures and frequent storms hit rats hard. Looking for something to eat, says Nessen, the rats turned to an unusual food source: chewing the bark off trees.
Rats eating trees is a novel behavior, and though it helped the rats get through the winter, it was pretty hard on the trees:
“Animals are drawn to the bark of trees because they're loaded with carbohydrates. But when rats eat a ring around a tree, as they've done in Kissena Corridor Park in Flushing, Queens, it can be devastating. Once a tree is girded like that, it typically dies.”
As we've written before, the long, cold winter the Northeast and Midwest just waded through was as hard (if not harder) on the region's animals than it was on its people.