White-breasted Nuthatches are coming to our feeders regularly now and have babies out of the nest. Makes the blood rush to my head to think of hanging upside down, but it's natural for this bird. Nuthatches can go down tree limbs as easily as they go up. This enables them to probe into tree crevices in search of insects from any angle. They also have a habit of wedging a seed in a tree crack to hack (hatch) it open, hence their name. They also store seeds in tree bark, including our bird seed!