Do the female bluejays have different colors?
There are a wide variety of jays in North America, a number of which are blue; however you specifically asked about blue jays, which are a particular type of jay. The male and female Blue Jay are identical: “Bright blue above with much white and black in the wings and tail; dingy white below; black facial markings; prominent crest” http://www.enature.com/fieldguides/detai… There is no difference in color, markings, size, voice or behavior.
