In New England, where I grew up, we had wood chucks, which we called whistle pigs. If they happened to see you and scooted down a hole, you could go to the hole, lay down and be quiet for a moment and then whistle. When they stuck their heads up to see what the noise was you got them.
(An Aside: The Town of Hopkinton, RI use to have a bounty on them. I think it was .15 cents a nose. We would pack the noises in salt and then get a ride to the town hall and collect our money. We found out that if we left them on the counter, the town clerk would give us an extra .15 cents to take them out and throw them away.
Then it was off to Kenyon's Store (where the post office is now) to buy the candy and soda.)
Gray Squirrels where referred to as tree rats.