Things you may not know about Blue Jays

Back yard Blue Jay, photo by kmenne

The All About Birds entry for Blue Jay (Cyanocitta cristata) says that these birds are known for their intelligence and complex social systems. Here’s a few facts – click above for more:

• 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.
• Their fondness for acorns is credited with helping spread oak trees after the last glacial period.
• Blue Jays are known to take and eat eggs and nestlings of other birds, but we don’t know how common this is. In an extensive study of Blue Jay feeding habits, only 1% of jays had evidence of eggs or birds in their stomachs. Most of their diet was composed of insects and nuts.
• The Blue Jay frequently mimics the calls of hawks, especially the Red-shouldered Hawk. These calls may provide information to other jays that a hawk is around, or may be used to deceive other species into believing a hawk is present.
• Tool use has never been reported for wild Blue Jays, but captive Blue Jays used strips of newspaper to rake in food pellets from outside their cages.

They add that the oldest known wild, banded Blue Jay lived to be at least 17 years 6 months old, and the UM Animal Diversity Web adds that one captive female lived for 26 years and 3 months. If you’re wondering where that ranks in the avian actuarial tables, it’s longer than a cardinal and shorter than a crane – click that link for the details.

Check this photo out bigger than a Blue Jay or in Keith’s nature slideshow.

More Michigan birds on Michigan in Pictures.