They know exactly when they need to migrate, feeding them does not keep them around any longer than they need to be. It is said that you should feed them for 2 weeks after you have seen your last one.

thank you very much catwhiskas :)

Isn't it the length of the daylight hours that determines when they leave.

Keep the feeders up and clean. The birds migrate according to daylight hours. They will leave when it is time. In the meantime, keep fattening them up.

Yes hummer migration is dependent on photoperiod. When the days get shorter they know instinctively that it is time to head southward to their winter home. The ones who may not leave are generally those that are too old or possibly ill to make the journey.

Penny

thank you all so very much

Keep at least one feeder up. There is a possibility that you will have a winter hummer at your feeder. After the first hard freeze that kills off their natural sources of necter, the somewhat rare winter hummers will be looking for a food source. You may be lucky enough to have one at your feeder.