They may not be Green-breasted Mangoes or even Rufous Hummingbirds, but right now I have TWO Ruby-throated Hummingbirds coming to my feeders! Keeping up feeders through September, October, and November does NOT entice hummingbirds to remain when they should migrate. But it does help baby Ruby-throats that fledged late or didn't have a chance to bulk up by the time they were supposed to leave, and it helps western hummingbirds that seem to be evolving to use a new wintering range in the southeastern US. I'll keep mine out (freshening the water every week, and more often when it's warm outside) until December.