Acorn woodpeckers, found along the western coast of North and Central America live communally in polyamorous groups. While their diet consists largely of insects they are famous for developing a complex system of acorn storage. “Granary trees” may be occupied and managed by a particular group for many generations and are actively defended against thieving squirrels and the like. If fresh acorns are just piled on top of each other they run a higher chance of rotting, by placing them in their own little cavity they dry quickly. As the acorns dry, they shrink and must be fitted into new smaller sockets lest they fall out. They prefer utilizing standing dead wood and old thick bark but are also happy to work on the redwood siding on your home. (Click image for larger version)
