I have heard a Black-capped Chickadee make a very defined two-toned call, it was more like a crisp "tee-too" than the usual calls I hear. The reason I know it was a chickadee is that I saw the chickadee make the call. I had followed the sound because it was so unusual to me and found the culprit.  Maybe there is a new slang word among teenaged chickadees.  I have not found the call among all the recordings I have listened to online.Michelle MaaniVancouver, WA
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman11.u.washington.edu/pipermail/tweeters/attachments/20190606/8808021b/attachment.html>