Common and spectacular, one of our most recognizable birds. Some migratory. Occurs in the deepest forest but just as happy in parks and gardens. Feeds on acorns, robs nests, and is regular at garden feeders, quietly sneaking in, and quick to leave. Raucous array of calls often announces presence but can be quiet and frustratingly difficult to find. Often feeds in treetops but just as happy hopping along on the ground. Some populations migrate. Usually in flocks, sometimes in 100s, as they migrate high overhead, contrasting black-and-white colors standing out. Rounded wings with bold white secondaries; tail tip and body contrast strongly with black underwing, collar, and base to tail. Bold white secondaries also prominent on upperwing. Does a great RSHA imitation among its many calls. ID: Superficially blue and white, but actually a remarkably complex variety of colors and patterns. Crested and thick-set with fairly long, graduated tail. Unique black throat collar. Juv: briefly held plumage, similar to adult but duller with blue or gray lores. Adult-like by fall but retains juv greater primary coverts, and alula lacks black bars.