Black-throated Blue Warbler in Millennium Park

I saw this very, very, very late Black-throated Blue Warbler in Chicago's Millennium Park on December 29, 2011.  Warblers are NOT expected in Illinois in December.  Previously the latest Illinois record for BTBW was November, 28, 2008.  They are a neotropical species which breeds in the deep woods of the northeastern U.S. and Canada.  Normally at this time of year, BTBWs are "wintering" on islands in the Caribbean, Costa Rica, and Panama, with the northernmost records being in Florida. 

A little research on eBird shows that a female BTBW was observed in British Colombia on December 18, 2011.  Since BTBWs do not breed that far west, her genetic impulse to migrate must be really mixed up, sending her west instead of south. 

Perhaps the male BTBW I saw will make it to the tropics yet.  It is highly unlikely he could survive a harsh Chicago winter.  BTBW diet mainly consists of insects and some small fruits.   He has been seen taking advantage of the sap oozing from a tree drilled by a Yellow-bellied Sapsucker (which is a little north of its typical range, too).  The presence of these birds underscores the importance of maintaining wildlife habitat in the middle of an urban landscape.  Vive le Chicago Wilderness! 

Both birds were easily seen from the sidewalk next to the Cycling Center.  I was especially pleased to add the BTBW to my Illinois list for the year (#242), since I had previously not seen any this year.  The handsome little guy was a real joy.