This is interesting one to be on the lookout for in ports or at sea:
Unidentified Motorola 3B36 Trunking System, Ship at Sea, Texas - Scanner Frequencies
Unidentified Motorola 3B36 - The RadioReference Wiki
Ships:
467.8 103.5 Bahamas Celebration (Celebration Cruise Line)
469.95 88.5 M Carnival Imagination - Bridge/Security/Excursions
467.5375 M Carnival Magic - Casino?
457.575 d 346 R Carnival Magic - Bridge/Security (main operations channel)
467.575 d 346 I Carnival Magic - Bridge/Security Input
457.55 d 212 R Carnival Magic - Engineering
464.275 d 346 M Carnival Magic - Guest Services/Excursions/Embarkation
459.65 S Carnival Magic - Paging (data)
156.225 CSQ M Carnival Magic - WaterWorks (Marine Ch. 64A) -- this is the onboard waterpark/slides
457.525 d 054 R Carnival Magic - "Safety Channel" (this is not security; it was used for emergency drills)
467.525 d 054 I Carnival Magic - "Safety Channel" Input
464.3 d 346 M Carnival Magic
467.175 156.7 M Carnival Pride - Bridge/Security
467.8 118.8 M Mariner of the Seas
467.75 97.4 M Mariner of the Seas - Ch. 5 Housekeeping
457.525 71.9 R Mariner of the Seas - Security
467.75 71.9 I Mariner of the Seas - Security Input
467.775 107.2 M Mariner of the Seas?
467.525 118.8 Emerald Princess?