While the male rt protects the feeder from 15 feet, how does he recognize his offspring and the female, to let them feed, everyone else gets buzzed away?

Do rt's return to the same area to breed each season?

Do the juveniles return to the same area next season to breed?

If they don't return to the same area, why do some stay south and some go to Canada? What makes them spread out?

Why do hummers buzz your face and seem to plot your facial features?

How long do there eggs take to hatch? And how long does it take the babies to leave the nest? How many clutches do they have per season?

How large of an area does a hummer stake out or how close can they nest?

Thanks for your responses in advance.