-- Those Kenting Blue Jays --

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The circumstance of Blue Jays doing expertly-rendered Ivory-bill 'kent' calls has long been an issue for IBWO searchers. There is no doubt that Blue Jays, well-known "mimics," utter a near perfect copy (to the human ear) of the Ivory-bill's signature sound. Why or how that arose is more a matter of debate, but anyway, I was amused to see a recent exchange on the Texas birding listserv... 
After a poster made note of a mockingbird imitating a blackbird's sound, Fred Collins chimed in with,

"And then there was the Blue Jay doing a perfect imitation of an Ivory-billed Woodpecker in Nacogdoches, TX in 2007. When and where did he learn that!"

To which another poster responded:

"Referring to Fred's Blue Jay doing Ivory-billed Woodpecker calls in 2007 the Blue Jays at Cache River in AR in winter of 2006 made perfect IBWO calls!! A call passed down generations that became a regular call or…"

Rarely, but occasionally, I've heard/watched Blue Jays give clear "kent" calls in my own area, where IBWOs were never known to exist, and it is a bit spooky!
Cornell attempted to address the issue of Blue Jay calls years ago, though I'm not sure much was ever resolved (though on spectrographic analysis they seem to feel they could differentiate the calls):

http://www.birds.cornell.edu/ivory/multimedia/sounds/listening/bjkent

I suspect we will never know why, how often, or under what circumstances, Blue Jays voice the calls, nor how much the frequency varies (if at all) by area of the country.

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