The dark-eyed junco is a frequent visitor to Midwest birdfeeders during winter, where they can be observed flashing white tail feathers while foraging. Junos flash their tail more often, and quickly, in the presence of a predator or when far from cover. Juncos flash their tail feathers less near cover or when in large groups. This indicates that winter tail flashing is used by individuals to deter predators by alerting them that they've been detected and that the junco is ready to make a quick getaway.
