It's $6 for the day, there is a fee machine to pay at or you can pay at the visitor center which is open Monday through Friday 9am-4pm. You're fee is also covered if you have a Federal duck stamp. There is no shuttle to take you around. The auto tour is self guided.
You can only drive around and get out of your car in designated areas to watch wildlife. They may do tours, better to ask at the office or call them. Also, if you have a national park pass or some kind of fishing pass, it's free. Otherwise the current fee will be posted and you will need to fill out a form and drop the payment in a box
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