As their name implies, acorn woodpeckers rely heavily on acorns for sustenance. To make sure this seasonal resource remains available throughout the year, the birds build enormous “granaries” by drilling thousands of holes into their oak-tree homes and stashing a single nut securely inside each hole. Since just one of these holes takes an average of 20 minutes to drill, the birds fiercely defend their granaries, and reuse them from year to year. The largest granary found to date was riddled with individual compartments for more than 50,000 acorns.

Unlike other woodpeckers—or virtually any other birds—acorn woodpeckers live in complex family groups numbering up to 15 adults, all of which work together to raise chicks in a single nest…

Why do they cooperate in this way? Scientists have been studying color-banded acorn woodpeckers at California’s Hastings Natural History Reservation for over 40 years to learn more about how and why these birds raise their chicks communally. Watch The Anomalies: The Acorn Woodpecker, a bioGraphic video produced by Day’s Edge Productions.

Next: From seed to sapling – Time lapse of an oak tree, Hummingbird hatchlings in their nest with mother Rosie, The Crazy Cribs of Parasitic Wasps, and how do cliff swallows build their mud pellet nests?

See more videos about...