The third opus of Alvin and the Chipmunks is officially titled Alvin and The Chipmunks Chip-Wrecked. Take a look to the first official plot synopsis:
"On vacation aboard a luxury cruise ship, Alvin, Simon, Theodore and the Chipettes are up to their usual antics, turning the ship into their personal playground, until they become 'chipwrecked' on a desert island. As Dave Seville frantically searches for his AWOL charges, the 'Munks and Chipettes do what they do best – sing, dance and wreak havoc. But they're in for a surprise when they embark on an island adventure with their new friend – a castaway who's more than a match for Alvin and the Chipmunks."
And here's a teaser poster of Alvin and the Chipmunks 3 Chip-Wrecked from the Licensing International Expo:
(Click on the poster to enlarge.)
On January 22, 2011, Fox 2000 Pictures started production on Alvin and the Chipmunks Chip-Wrecked during a Caribbean cruise on the Carnival Dream ship. Filming took place primarily on the ship's upper, open decks with scenes featuring actor Jason Lee (reprising his role as Dave Seville) and the antics of The Chipmunks in the Carnival Dream's outdoor recreation areas. Stops on the itinerary included Cozumel, Roatan, Belize and Costa Maya (which provided tropical backdrops for many of the movie’s shipboard scenes).