I think I know the answer to this but.... Does a ship observe time zone changes that may occur from port to port? Do I have to figure these out in advance so I can set my alarm clock appropriately along the way so I won't miss my early morning excursions? Or does the ship have a way of reminding us of these changes when they happen?
The ship rarely if ever will change the Ship's time. They plan all events by Ship's time, and excursions, and ESPECIALLY arrivals/departures. KEEP YOUR WATCHES ON SHIP'S TIME! Also find out the time difference between the ship and land.
They will only change the time if the cruise is a long repositioning cruise (IE Miami-los angeles, we changed ship's time as we went west) or daylight saving's time changes.
Holiday 5-day Western Caribbean
Liberty 8 day Western
If for some reason they do have a time change, they will let you know. Just be sure to read the daily news letter they leave you each day, it will be in there if you need to change your watch, but usually you just stay on the time it is when you leave the embarkment port.
It really depends a lot on the line and the itinerary whether they change ship's time. As others have said, they publicize it well.
Also note that on just about all of the newer ships there's an LCD clock on the telephone. This clock is slaved to ship's time, so if there's a time change, the clock changes. This is useful because it's also linked to the automated wake-up calls, so if you program a wake up call it will ALWAYS be on ship's time, whether there's been an adjustment or not.
Naturally, on long voyages, and especially crossings and Canal cruises, they do adjust the time, sometimes for several days running, so that you're not all goofed up when you get where you're going.
When I cruised in April 2004 the ship stayed on DST the entire time. Grand Cayman, Costa Maya and Cozumel were an hour behind the ship and Belize was two hours behind. I kept my watch set to ship's time and carried another watch in with me set to local time and found this helped us keep track.
Celebrity Century 1/09
Carnival Destiny 10/07
Carnival Destiny 9/06
Monarch of the Seas 3/06
Carnival Inspiration 8/05
Carnival Miracle 4/05
Carnival Inspiration 4/04
Sovereign of the Seas 4/03
Norwegian will inform you by way of the Freestyle news and the captain will make a few announcements about time changes plus you will also get a separate card placed on your bed at night regarding time change information.
On all of the cruises I have taken, the ship has changed time to the local time for the port we were entering. As others have said, this is well publicized in advance, either by the daily newsletter, or by a card or flyer in the cabin.
"Twenty years from now, you will be more disappointed by the things you didn't do than the ones you did. So throw off the bowlines. Sail away from the safe harbor. Catch the tradewinds in your sails. Explore, Dream, Discover."
For some reason, Carnival does not change times. So you have to be aware when you are on a land excursion, or for that matter, shopping. If you think you have time to get to that shop for that had the cute little doo-dad, it may be closed due to the differing times.
NCL does change times on sea days to lessen the confusion. That way, you are in sync with the local times.