I feel guilty that I did this but it seems to have worked.

A pair of geese became fond of my lawn in early May. At first I thought it was no big deal. 3 weeks later my backyard was a mess from droppings. These things can really poop! I tried sticks and rocks for awhile; I never hit them and they seemed to be amused with me. I then switched to my son's paintball gun and everything changed. They were afraid of the noise and a couple of whacks in the A*S with a few paintballs seems to have convinced them to leave. 2 weeks later I have no geese and no poops.
I love NH and I love nature but these birds had to go. Please note that no actual Canada Geese suffered any lethal hits from the paintballs.