For three years now, we have had a pair of hummingbirds in the summer and later in the season, their offspring, coming to our backyard feeders. Of course we don't really know if they are the same individuals, but we like to think they are. My daughter named the female "Ruby" (of course) and the male is "Reggie". We can't wait for them to arrive in the spring and always feel sad when they leave as we get so much pleasure watching them. In fact, that is often our dusk entertainment. At any rate, the last time we definitively saw Ruby was Sept. 16th and haven't seen Reggie since Sept. 9th. You can tell they're getting ready to migrate because they're all over the flower garden and at the feeders all day long fueling up whereas they are normally a bit shy and mostly coming at dawn and dusk.
Last year, we had newcomers to the hummingbird feeders and I never would have believed it possible, but a pair of downy woodpeckers come after they're done breeding and apparently they really can get the nectar out! My neighbor has the exact same phenomena going on in her yard. So even if our hummers are gone for the season, this is some sort of consolation.