Imagine, for a moment, a truly enormous squid or octopus. Imagine, then, that it wants to attack a ship. Could it move its tentacles “onboard” the ship to snatch crew, rip riggings to pieces and so on and so forth without having any support other than the sea, or would it need to be at a shallow enough depth that it could support itself against the ocean floor with a tentacle or two?
They have suckers to grab the sides of the boat.
It’s thought that they have in the past, back when sailing ships were the norm.
The classic Kraken drawings do show the Squid holding the boat for levage as it plucks off the hapless sailors.
Jim
Terrifel made a terrific post about the colossal squid here a little while ago. He may be the one most able to answer your question.
The person who could probably most ably answer your question is Steve O’Shea who has just posted to Terrifel’s thread.
I wouldn’t think that special knowledge of squids is required to answer this question; it’s a physics question. Can a tentacled marine creature use those tentacles against enemies above the surface without supporting itself against the ocean floor?
I think the main problem would be the lack of buoyancy. Experiment: stand up and hold your arm straight out from your body for two minutes. Your muscles start to ache after a bit, don’t they? Yet, if you repeat the same thing while in water, it’s not difficult in the least, you can almost rest your arm on the water without it sinking.
I soubt a squid has the muscles to hold its tentacles straight up into the air, and it would need to in order to get them onto the ship.
Well, I’d think that support against the ocean floor would not be necessary as the squid should be able to support itself with the water.
Sofis’s point is more to the point IMO. Just how effective are the tentacles out of the water?
Yikes… Thanks for the kind words, Plynck, but please don’t imagine that I have any special credentials in molluscan biology. Remember, I was the one *asking * the question; I’m the ignorant one demanding brain food in that situation.
My totally air-fueled guess regarding the OP would be that a hypothetical gigantic cephalopod would need to be able to brace itself against something before it could lift its arms far above the waterline, and the most convenient source of leverage would be a grip on the hull of the ship itself. However, such a scenario has probably never actually happened outside the pages of fiction. Octopus have some ability to maneuver their arms while out of the water, but even the largest known species don’t reach anywhere near the necessary size to properly drag screaming sailors from the rigging.
The giant squid has the longest reach, but I believe its tentacles don’t have the necessary muscle structure to support themselves above water. I’ve read that it may be possible for the giant squid to lift its shorter, more powerful body arms slightly above the waterline while floating in open water, which suggests that they might be able to menace a boat with a sufficiently low freeboard. I seem to recall that one of the earliest historical encounters with the giant squid involved a couple of guys in a rowboat who ran across a dying one drifting in the tide along a rocky coast; supposedly the squid managed to get one of its arms over the gunwales, whereupon one of the fellows promptly lopped it off with a hatchet. Of course, in this situation the squid may have been able to secure leverage against the hull of the rowboat, and possibly also against shallow rocks or seafloor.
I’ll try to flag down Dr. Steve O’Shea and draw his attention to this thread when I next post to the other one; he may have some professional insight to share.
The squid doesn’t have to lift its arm at all. They can slither their arms like a snake using the suckers. So they can effectively slide an exploratory arm up and over the rail without ever lifting more than the tip.
Hey Priceguy, all you have to do is rent the movie “Deep Rising” starring Treat Williams. It’ll tell you everything you need to know. 
Well, I can certainly grab a beer from a friend on terra firma whilst at the deep end of the pool without touching the bottom or sides, so I don’t think physics would be violated. Are you asking about tentacle design? My pool experiments won’t answer that…yet.
Well, explanations are OK, but I’d really rather have the good Doc spend his time breeding a truly large, butt-kicking, killer squid that could reach up and drag a few hapless mariners off the deck. Something that “Jaws” would swim respectfully aside for. I want some damn seamonsters worthy of the name!
Testy