I think that the ship will take care of this. But here it is ....
To enter The Bahamas, U.S. citizens need one of the three documents listed below, accompanied by a return or onward journey ticket and proof of funds to support the visit. Stays not to exceed eight months.
A married woman whose birth certificate does not match her Government issued identification should also bring along her marriage license.
If you are using an electronic ticket, please show Immigration a copy of your travel itinerary and ticket number.
Current or expired (up to a maximum of five years since expiration date).
Official Birth Certificate
For persons 17 years of age and older:
An original certificate issued by the U.S. Govt. or court-certified copy (raised or ink seal) is required, accompanied by an Official Photo ID issued by the U.S. Govt. (driver’s license, or voter's card). Current and expired IDs are accepted. Student Photo ID alone is not acceptable as adequate documentation. "