You should be able to bring them onboard, but, I would call the cruise line and perhaps get something like an email in writing from someone telling you it is ok.
I don't scuba anymore, but when I did, I never used a knife. What is it that you are expecting to encounter?
I'm a divemaster who doesn't worry about critters. I worry more about foolish humans. :-)
I once had to cut a buddy out of a tangle of fishing line. If I hadn't had my knife... well let's just say it would of turned out different. So I carry one for emergencies. Not to use on unwary sea creatures, but just in case.
I've been there and I know of what you speak. But I have found that my cut anything huge scissors are better on fishing line than any knife.
Where will you be diving on your next cruise? I wish I was there too.
Reggae (African Grey Parrot)
Valor Jan 8, 2006
Triumph May 12 2007
Triumph November 3,2007
Liberty November 22, 2008
Miracle March 4, 2010
Glory Jan 16, 2011
Spirit Sept 11, 2012
Fascination September 22, 2014 Kansas Concert, Nassau and Little Stirrup Cay
Funny you should ask. A running joke on the Glory in June was "less than 4 inches". A young man bought some sort of knife at one of the ports. Security gave him a hard time insisting that the blade had to be less 4 inches in length. The did let him on board.
I have brought mine on board, post 9-11 but it is small and it actually clicks into a sheath attached to the back of my dive computer so I am sure no one took notice of it. No stabbing starfish, but definitley good for an emergency - like the fishing line nightmare described herein.
Thanks for all the help. I'll let my DH know. We are going to dive Grand Cayman. Do a wall dive and then a reef and then a quick trip to Stingray City . Does anyone know what the closest reef in to Stingray city? Recommendations?