Possible Clues:

• Het gets to where he can drive, of course, in the water
• Plant-eating mammal
• Heavenly food and drink, say, for a sea creature
• This swimmer's crew had a supporter of course
• Give him a place to drive into the sea
• Dugong's cousin
• Mammal linked to mermaid folklore
• Marine muncher on mangrove leaves
• Marine mammal of the Everglades
• Hefty ocean animal