Sheryl, Something I saw said researchers believe it's due to the "global warming" thing why they are overwintering more than before.
Here's another link. I'm getting closer to finding that study because I remember this site associated with it somehow. Drat it all --- some time ago I lost all my bookmarks & that's where all this info. was ......Grrrrrrrrrrrrrrrrrrrrrrrrr.
Anyway, this is good:
http://www.hummingbirdresearch...
