Cues from Nature
These observers know it's time to say farewell to their hummers. Their comments help us see how hummingbirds pay attention to seasonal cues and weather events:

"Today matches last year's last sighting date for hummers in our yard (9/26). Two females were off to bed last night at 7:17 p.m. Very interesting that they know the days shorten so they go to roost a minute or so earlier each evening as another hummer season draws to an end. I would be very surprised to see any hummers at the feeders this evening."

Mike in Oakdale, Minnesota (September 26, 2013)

"After a rainy day and cold night, a female made two feeder visits— one at 15 minutes before sunrise and one at two minutes after sunrise. She must have made good use of the cold wind blowing out of the north and started her long journey south.”

Glenna in Mississauga, Ontario (September 22, 2013)

Photo: Carole Bradshaw, Brant Beach, NJ