New York is home to beautiful nature and outdoor activities. If you’re out walking in the woods or even in your backyard you may notice a large ball of leaves up in the tree. It’s not a bird’s nest, it’s something that squirrels make to try to keep warm in the winter known as a drey. Squirrel nests or dreys consist of branches, moss, and pine needles and are built near the trunk or at the fork of two strong branches for stability.