We use disposable
aluminum roasting trays (one) set into the
toilet.
A very little bit of litter, and frequent emptying, including immediate feces
removal.
They'll take to it immediately. You could also try one of the
commercial train-your-cat-to-the-toilet contraptions before you leave, and maybe it wouldn't be necessary for the pans. We tried to do it without, and failed, but there was NO question that they went right to the
head.
Non clumping, and once we reached the
Bahamas, it was all beach sand (with litter aboard when we weren't there or able to get ashore)...
A clue for their comfort with cruising will be to get them to an open anchorage for several days, where the motion of the
boat, without your being under way, will acclimatize them to the motion.
Portia would absolutely revel in the sound of the
anchor going down; she knew that the
passage was over. Conversely, she'd dive for the berth when she heard the
engine start, until we were under way.
Cats thrive aboard, and are not any real difficulty, other than that you'll want to make sure they have an accustomed place to scratch. In our case, it's the bottom of the
mast which we've wrapped in light line.
If you're worried, take them out
boating every chance you get...
HTH...
L8R
Skip
PS Portia and Greta are ashore being
service animals for Lydia's mother, who cruised a couple of times with us, both with Portia. We gave her Portia when she came to the US to go cruising but got too old while we finished the boatyard stuff (2011-2012
refit in the gallery).
Our shakedown garnered Greta; when we arrived on
Christmas Day 2013, she moved off the
boat to be with Portia. When her mother is gone, they'll come cruising with us again.