I found this while browsing the OhioBirds list. It would be interesting if this theory proved to be true. Seems like the most reliable place recently to find Mississippi Kites is St. Mary's county but Calvert, Charles and St. Mary's will not have periodical cicadas with brood X. Perhaps some other DC/Baltimore areas will luck out.

Tyler Bell

California, Maryland

Wave that flag...wave it wide and high!
Grateful Dead, U.S. Blues

Subject: Cicada-Kite Connection?
From: "david j. horn" <horn.1 AT osu.edu>
Date: Thu, 13 May 2004 09:48:39 -0400

Hello Ohio Birders,

With the 17-year cicadas upon us (in western Ohio) I'll reiterate my 
posting of a few years ago: there is anecdotal evidence that Mississippi 
kites may move into an infested area to feast on cicadas.  I thought I'd 
give this heads-up to those of you in the Cicada Zone: be on the alert for 
Miss. kites at or around cicada aggregations.

Happy birding.

Dave Horn