The bird above was spotted in our neighborhood on the east side of the city and the ones below at the eastern end of Belle Isle. We don't seem to see as many of these as we do Cardinals and as a result, S. gets a little more geeked when we spot them. S. tells me that Blue Jays like to eat acorns and the oldest known wild Blue Jay was over 17 years old. Cornell University's Lab of Orinthology notes that:
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.
To see video and audio of the Blue Jay, see here
UPDATE: Spring 2010. This Blue Jay really stood out among some burnt forest cover at Belle Isle.