I operate one of the contract charters that Princess uses in Juneau. We're told that each group returning to the ship may bring ONE fish back to prepare for dinner. If there are left-overs (ie: a 40# King Salmon for a family of 2) they will store it for you. Be sure you have someone at home to receive it, as you don't want fish thawing on your doorstep while you're away on vacation. I would also wonder what happens if you catch more than one fish?
Unless it's a new Princess policy, any charter can provide this service, but you've got to bring a specific form that you get from the Purser or ShorEx desk that we fill out on the boat to "transfer possession."
To the best of my knowledge, no other cruise line will do this. It's quite a hassle with all the new health and Fish/Game regulations about not putting sport-caught fish in a commercial kitchen. (A local restaurant was just closed and searched because they they were suspected of having sport-caught halibut in their freezers! Imagine the problems that would be caused if a cruise ship had to stop for a day to be searched?)
The "usual" (and far less expensive) way of going about this is to privately charter a boat that delivers your fish to a local cannery where they can smoke it, fillet it, can it, whatever you'd like done... they then hold it frozen until they contact you at home to be sure you're there to receive the shipment. Unless you've got a LOT of fish, it's not all that expensive to process and ship anyway.
Please don't book the "cheapest charter"... no matter the savings. With water temperatures running in the mid 40's in May, and our "normal" weather that just can't be predicted, I would hesitate to get on any boat that wasn't 5-Star Safety Certified to begin with. "The bitterness of a poor job will always outlast the sweetness of a cheap price!"
Ask how much time you'll spend actually fishing. Here in Juneau, a 4 or 5-hour charter will run between $150 and $250 per person for a shared charter and between $500 and $1200 to rent the whole boat privately. I believe the Princess trips cost $199, and I KNOW you fish for between 2.5 and 4 hours per trip. If you don't book a whole boat privately, you'll be sharing your fishing time with up to 5 others from your cruise. This is fine, but most of the Princess contract boats only fish with 4 rods at a time, and the anglers "rotate" and take turns catching whatever comes along... How will you feel when you're 5th in line to catch a fish and only 4 fish are caught that day?
Sorry this got so long... hope any of it helps.
Happy Alaska Travels!
-Case