I've been to Bay Islands, Belize
, & Guatemala
aboard (cats & a parrot, dog in Belize/Guatemala).
Cats are easy...just the normal current health
papers etc. Belize is a bit more of a PITA of course (because that's just the way it is in Belize) and they charged BZ$100 per animal for doing absolutley nothing. Guatemala
were easy with no crazy fees
This was number of years ago so check official web sites (embassy/consulate) for current
For Belize animals
fall under BAHA. http://www.baha.bz/
For current Guatemala info check with Raul (agent in Livingston).