depends.
--from travelocity--
BEFORE YOU GO: Bahamas
ENTRY REQUIREMENTS AND CUSTOMS:
-Valid photo I.D. (driver's license is fine) AND a government-issued birth certificate (not hospital-issued) with a raised seal, OR a valid Passport.
-Non-US citizens, please contact the nearest consulate or embassy of the country to which you are traveling to determine your entry/visa requirements.
-Upon arrival in The Bahamas, you'll be given an Immigration Card to complete and sign. The Bahamian customs official will stamp the card and return it to you. Be sure to keep the card in a safe place, because you'll need to turn it in upon departure from The Bahamas.