Michigan has open season on them:
Opossum, porcupine, weasel, red squirrel, skunk, ground squirrel, woodchuck, Russian boar, feral pigeons, starling and house sparrows may be taken year-round with a valid Michigan hunting license.
Opossum, porcupine, weasel, red squirrel, skunk, ground squirrel, woodchuck, Russian boar, feral pigeons, starling and house sparrows may be taken year-round with a valid Michigan hunting license.