I know that this is a bit off topic, but we'd been discussing mimicry previously.
There is an "oasis" in the dry grasslands and farmlands of se. Colorado known as Tempel Grove, after the owner. There was a N Parula hanging out there, singing, for more than a week this spring. I went back yesterday, just to see if the parula, or anything else odd, had decided to hang out for the summer.
I played the N Parula tape, and to my surprise, had an almost immediate and vigorous response. Only, it sounded a bit off. Pattern seemed really good, and pitch within ballpark, but there was no buzzing quality. The bird came readily in... and it was a House Wren. I was standing at the spot at which the parula had been hanging out. It is not a tremendous surprise that the House Wren incorporated some of the N Parula into its song, but the degree to which it did seems somewhat surprising, and the bird's response to the parula tape exceptional.
So, for whatever that is all worth... I am danged glad I saw the wren, because otherwise, I'd have been plenty baffled.
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