You've probably heard the myth: Take down your hummingbird feeders in the fall or the hummers will "forget" to migrate. It's not true. Birds, including the hummingbirds at our feeders, are programmed by instinct to migrate when their inner clocks tell them to leave. Changes in daylight (in terms of the length and intensity of sunlight) and weather dictate the birds' departure date. There's no way your feeder will interfere with a bird's migratory urge unless the bird is hindered from migrating by some other factor such as illness or injury. Sick or injured birds and late migrants from points to the north of you will benefit from your late-fall feeding station. Leaving your hummer feeders up will do no harm, and it might even do some good. Just make sure your feeders are clean and the solution is fresh. No need to keep the feeders full at this time of year, but do provide a bit of fresh sugar water until it starts to freeze overnight.