Unfortunately, since the skunk is accustomed to eating pet food (even when the pets are present) it will be hard to convince the skunk to leave. Making sure that the skunk does not have access to the pet food is the first step. The second step is to block access under the deck. If you remove food and shelter the skunk may move on to another area. However, this is the time of year when skunks are caring for young. So you would need to make sure that the skunk does not have any kits under the deck. Another option would be to hire a nuisance wildlife control operator to trap and remove the skunk. You can find operators in your area on the "Find a Professional' page of this website.