The Storehouses of Acorn Woodpecker
Woodpeckers are captivating birds. They have a tightly packed brain, a compressible sponge-like skull bone to absorb the impact's energy, and an elongated tongue-bone that envelops around the skull, amortizing the brain. Most species of woodpeckers peck at trees in search of insects, but the acorn woodpecker, drill holes to stock food.
The acorn woodpecker's preferred food is an acorn. When winter nears, the acorn woodpecker will start keeping acorns in storehouses built out of tree trunks, telephone poles, and even wooden houses. The acorn woodpecker drills thousands of holes just large suitable for a single acorn, and they aren't forced too deep into the trunk so that their recapture is more leisurely.
Because the acorns are put in shallow holes, they are noticeable from the outside, which interests prey, and thus storehouses have to be protected. Large storehouse trees that contain enough food (in some cases 50 thousand acorns in a single tree) are often protected by several woodpeckers.
Storehouses also need regular maintenance. As acorns dry out and shrink, they are transferred to smaller holes, and new acorns load the vacated ones.
The acorn woodpecker inhabits mainly in western U.S. states (Oregon, California).