The call of the Red-Throated Ringtone

Today while walking outdoors in the suburbs, my phone let me know that I had a new text message.  Brrrrr-tink!  My phone was all the way in my backpack; ehhh, I'll let it go a few minutes, I thought, until I arrive at my destination.

Then, Brrrrr-tink!  Brrrrr-tink!  Brrrrr-tink!  Well, it must be something important if I'm getting four in a row...  So I wrestled open my backpack, scrabbled around for a while in the middle of the sidewalk, and finally fished the phone out.

The phone which had no new texts.

I pondered this paradox, staring dumbly at the phone.   Inexplicably outsmarted by technology.  Again.

And then I got another text.  Brrrrr-tink!  Curiously, my phone stayed quiet and dark.  And even more curiously, the sound came from the nearby tree. 

I looked and looked, but I couldn't find the culprit, even though he called several more times.  I wonder if that is his usual call or if he's a mimic.