The acorn woodpecker (Melanerpes formicivorus) is a bird in the woodpecker family, Picidae. It is found across Central America, as well as the western United States and parts of Colombia. A medium-sized bird, it has a length of around 20 cm and is mostly black, and adult males have a red cap starting at the forehead and females a black area between the forehead and the cap. As their name implies, acorn woodpeckers are heavily dependent on acorns for food, which they store in small holes that they drill into trees, known as "granaries" or "storage trees". This acorn woodpecker was photographed in the grounds of California State University, Chico, United States.Photograph credit: Frank Schulenburg