Heard a Mockingbird today

Heard a mockingbird today singing its heart out in the middle of a bush as we walked east on 23rd St in the middle of the day.  At first we thought it was an alarm, the sound was so exaggerated and loud.  Then I located the animal, his head thrown back like Edith Piaf, going through its extensive repertory of imitations, including a catbird, a starling, a robin, a catcall, an engine warming up, a towhee, a whistler, and on and on it went.  Another man paused to listen. He didn't need to look, just to listen as the concert continued for five minutes.  No amplifier needed, this thing was singing for the upper deck.   The bird's white-streaked tail was tipped way up to the moon as it gave its heady aria to all passersby for free.  It was full of joy.