Hi Richard you could try to flood them out by sticking a hose as far down the hole as posible and let it rip,however this could lead to creating a large under ground cavity so be carful if you try this.Best methed is patience and a good aim if you live in the country get yourself a 22 cal. if your in town then use a .17 cal air rifle.and use the pointed pellets. Gary Amber Wave Gardens Benton Harbor MI. zone 6