Acorn woodpeckers aren’t afraid to pick a fight.
Like other woodpeckers, they make holes in trees and even telephone poles. However, instead of looking for insects to eat or making nests, acorn woodpeckers use the holes to hold acorns. Acorns are the nuts that fall off oak trees.
The trees that the woodpeckers make holes in become storage shelves, holding acorns until the birds are ready to eat them.
The small, red-headed birds are also unusual because they live in large groups. That may be why when one of the woodpeckers dies, the others begin fighting to take over that birds acorn-gathering spot. Other woodpeckers will even come to watch the fights, traveling from long distances to see the battles.
"When you're approaching a big tree with a power struggle from far away, you'll first hear a lot of acorn woodpeckers calling very distinctly, and see birds flying around like crazy," says Sahas Barve, a researcher at the Smithsonian National Museum of Natural History.
Using small radio tags attached to some of the woodpeckers’ backs, Barve and his fellow researchers learned how much time the birds spent fighting and where they came from.
Some of the birds fought for 10 hours. The birds that came to fight for territory were often brothers or sisters from nearby territories.
The biggest battles might attract more than 30 birds, some coming from almost two miles away. Some of the birds who came to watch spent up to an hour viewing the competition.
You won’t see acorn woodpeckers in Montana. They live on the West Coast and in the Southwest. Keep your eyes open if you ever go to those areas. See if you can find one of their unusual storage trees, and keep a lookout for a bird battle.
— Brett French, firstname.lastname@example.org