Blue jays are permanent residents throughout Minnesota, but many of these birds, especially those nesting in the north, head southward out of the state in early fall. They travel by day in flocks of 10 or more. About a foot long and mostly blue and crested, they are unmistakable. A blue jay's feathers don't have blue pigment but look blue because of refraction (bending of light rays) of sunlight off their irregular surfaces. Male and female blue jays look alike. They are smart, adaptable and vocal. Besides the noisy "jaay-jaay" call, they make a variety of squeaks, rattles and croaks. They even scream like a hawk, which causes other birds to scatter as they approach a bird feeder. Now, with increasing daylight, we hear their "pump-handle" call, also called the "spelunker" call. It's a wonderful sound considered a marker of early spring.
While a single blue jay can bury thousands of acorns over the years, many are never retrieved, and jays are credited with helping to regenerate forests. As omnivores, blue jays eat berries, acorns and other seeds, insects, spiders, snails, frogs, small fish, and bird eggs and chicks. They also eat a variety of human-supplied foods.
Sometimes persecuted by humans as nest robbers or bullies at feeding stations, blue jays deserve credit for alerting other birds and small mammals to the presence of hawks, owls and other enemies.
Jim Gilbert's Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.
