Englishman, you're going to hate me for this.... Here in North America, at least in the North-East where I live, it is said that some foolish english guy brought red squirrels from England, and they are now outnumbering the local grey squirrels. The red ones have taken over the grey's habitat and food.
My son shoots the red ones with his BB gun and feed them to the neigbor's boa constrictor.... I must say that I love watching the critters, but they are so numerous, and they chew holes into the attic and make a mess....
The chipmunks are also very prolific and destroy gardens.... Boa constrictor food....
Let me also add that I feed the red squirrels along with a rare grey one and dozens of different birds all winter at my bird feeder, and choice seeds, a mixture of peanuts, sunfower seeds, millet, thistles, etc... hunting is not allowed in the winter