This common, large songbird is familiar to many people, with its perky crest; blue, white, and black plumage; and noisy calls. Blue Jays are known for their intelligence and complex social systems with tight family bonds. Their fondness for acorns is credited with helping spread oak trees after the last glacial period.
Thousands of Blue Jays migrate in flocks along the Great Lakes and Atlantic coasts, but much about their migration remains a mystery. Some are present throughout winter in all parts of their range. Young jays may be more likely to migrate than adults, but many adults also migrate. Some individual jays migrate south one year, stay north the next winter, and then migrate south again the next year. No one has worked out why they migrate when they do. The pigment in Blue Jay feathers is melanin, which is brown. The blue color is caused by scattering light through modified cells on the surface of the feather barbs. The black bridle across the face, nape, and throat varies extensively and may help Blue Jays recognize one another.
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