Im just wondering if the colossal squid has strong tentacles and a colossals main food source is pagantonian toothfish Also can a colossal squid predate like on a small shark or does it just stick to pagaontian toothfish.

Im just wondering if the colossal squid has strong tentacles and a colossals main food source is pagantonian toothfish Also can a colossal squid predate like on a small shark or does it just stick to pagaontian toothfish.

:welcome: to TONMO

I'll be curious if Steve and Kat have any insights here, but I'm pretty sure any answers will be speculation (unless there were some gut contents I've forgotten.) However, extrapolating up from more reasonable-sized squids, Mesonychoteuthis tentacles are probable quite quite good at holding large fish and pulling them in. They have shorter, thicker tentacles than Architeuthis and their hooks are clearly well-suited to keeping a grip on large prey animals, so it seems like a safe bet that they would immobilize a large fish like a toothfish with a tentacle strike and be strong enough to pull it into the arms for lunch... but I doubt you'll find any volunteers to put on a dry-suit and dive in the Ross Sea to find a huge squid to have a tug-of-war with to get a solid answer... (although Steve has been on a kick of proposing, er, exciting new projects for his students!)

Also extrapolating from smaller squids, I'd bet that it would eat any fish between a tenth and half (conservatively) of its own size, and I doubt it would turn down a shark, and few sharks are big enough that I think an adult colossal squid would be intimidated by them.

Please note, that the pacific sleeper shark (Somniosus pacificus) feeds on Mesonychoteuthis. It is not known whether this is through active predation or scavenging behaviour...

Mesonychoteuthis' tentacles are very muscular indeed, just look at this well known picture from Martin Collins of the South Georgia Island specimen :shock:

Thx for the pic and thx monty I like the forum.So a colossals tentacles are short and thick meaning they might have alot of strenght behind them

No one appears to be in disagreement with you there :wink:

The prey that M. hamiltoni grapples with is very powerful, so it needs the over the top armament.

Thx and the pic was that a adult colossal?

They never retrieved the mantle, but judging on size, likely sub adult, possibly adult; we really don't know exactly how big they get...

:
Also extrapolating from smaller squids, I'd bet that it would eat any fish between a tenth and half (conservatively) of its own size, and I doubt it would turn down a shark, and few sharks are big enough that I think an adult colossal squid would be intimidated by them.

So,it would seem that you are saying that most
"Predatory" squid would only make attempts on a
50 percent smaller shark at minimum.
-I'm not in disagreement(Though,what do I know).

But,it seems like the reverse is not true.
-By way of this example:
""The afternoon’s Mako, a sleek nearly-five-footer, had something I have never seen before, or even heard of: wounds from a Humboldt Squid. The Mako’s sides carried marks from rows of suckers, and slashes seemingly from the squid’s beak!"
"Last night we spent a couple of hours jigging for Humboldt Squid and caught two “small” ones that were the largest squid I’ve ever seen alive. Today, no fewer than three of the Makos we caught had squid sucker marks on them. Because the marks were concentrated on or around the head, it appears the sharks are attacking the squid and not vice versa.

We also caught one mako shark that looked as if it had been feeding on a Humboldt squid. It was covered with the repeated circular markings of the suction discs of the squid's tentacles. We first noticed these squid marks on mako sharks last year. Research at our lab at the Southwest Fisheries Science Center has shown that Humboldt squid are a common prey of mako sharks in this area".

And this too.
http://i57.photobucket.com/albums/g235/scottwolverine1111/sharkfilesandpictures0004.jpg
http://i57.photobucket.com/albums/g235/scottwolverine1111/sharkfilesandpictures0005.jpg


Though,hombolt squid also being opportunistic,will attack a (larger than themselves) shark if the conditions are right.

""During one night dive, a passenger aboard the ship hooked a 14-foot thresher shark, and the four photographers jumped in. As the photographers' flashes went off, they noticed dozens of other lights streaking around them in the water. One of the red and white streaks—a jumbo squid more than six feet long—flung itself onto the weary shark, ripping a fist-sized chunk of flesh from its head"

http://216.109.125.130/search/cache?ei=UTF...&icp=1&.intl=us.

So,my point is ?.....Actually I've no Point,lol.(I'm still trying to figure it all out).

I was trying to be conservative; certainly, some smaller cephs will kill animals larger than they are... the GPO vs Shark video that floats around shows an octopus taking down a shark that's bigger and heavier than it is. And humboldts hunt in packs, so that picture could easily be reversed in that case; the common belief seems to be that Architeuthis is pretty solitary, but as far as I know the only evidence that Colossal squids are not pack hunters is that they've only been seen going after the toothfish one at a time... certainly, many large carnivores become solitary just because of the need to spread out to get the food resources, but wolves, lions, and whales come to mind as large pack-hunting critters.

The link to 216.109... just gets a "yahoo search can't process your request" for me... does it show where that picture came from?

Concerning the link,I will fix it a little later,sorry about that.

Monty,I mean no disrespect,but to me,it looked like the GPO was much larger than the shark.Now,I'm a novice here concerning marine biology,so perhaps you can elaborate on..
1)Is indeed the shark larger than the GPO?

2)If so,then it must be that cephalopod weight/mass is difficult to predict from just looking at its diminsions.

3)Or.....Perhaps I may need glasses.

Again,I'm just a beginner here,so don't be offended by my "ignorant,but learning" questions.

http://216.109.125.130/search/cache?ei=UTF-8&p=squid+predation+on+shark&fr=ytff1-msgr&u=discovermagazine.com/2007/jul/jumbo-squid-invade-california-coast&w=squid+squids+predation+shark+sharks&d=Zupq97XiQGC-&icp=1&.intl=us

Concerning the link,I will fix it a little later,sorry about that.

Monty,I mean no disrespect,but to me,it looked like the GPO was much larger than the shark.Now,I'm a novice here concerning marine biology,so perhaps you can elaborate on..
1)Is indeed the shark larger than the GPO?

2)If so,then it must be that cephalopod weight/mass is difficult to predict from just looking at its diminsions.

3)Or.....Perhaps I may need glasses.

Again,I'm just a beginner here,so don't be offended by my "ignorant,but learning" questions.

well, re-watching it I guess the shark is smaller than I remembered, but it's sort of hard to compare, since a shark is long, thin, and muscular, while an octo stretches and moves. It would be interesting to know which weighs more...

I have seen pictures of squids and cuttles attacking things that are about their size or slightly larger than they are, though, but they haven't been sharks, I guess. But I bet if you take the weight of the GPO and shark in the video, and compare the ratio, that (admittedly unjustified) approach would suggest that a 500kg Mesonychoteuthis could probably take on a pretty big shark, although I note that the wikipedia page for Great Whites (http://en.wikipedia.org/wiki/Great_white_shark) says that they reach 2,250kg. So the biggest shark outweighs the biggest squid by quite a bit, and that's just 6 feet long, which at least makes it plausible that the squid outweighs the GPO in that video even if it's a bit smaller in length.

In a contest between a ceph and a shark of the same weight, I'd expect there's not a clear winner... if the ceph got a good grip on the shark, the shark doesn't have a lot of options, but if the shark took a big chomp out of the ceph, it could easily cause fatal damage... they're both very effective "first strike" predators.

Caveat emptor: I've read a lot about this stuff, but I'm wishing the real biologists would chime in, 'cause I am somewhat in "conjecture" territory here...

Indeed,I would pay good money to hear what Dr. O'Shea has to say about it,good or bad.
"Who shall I make the check out to?"

In my experience, he prefers payment in good cheer to outright bribery.... he appears to be rather busy lately, but may well pop in and comment on the subject.

Question the club with the hooks can it also proform blunt trauma like bruises or just lacerations/cuts.

Blunt trauma would be the territory of things with bone or cartilage in it, or a very strong exoskeleton imo...

Most squids seem to use tentacles more for grabbing and grappling, but the SeaWolves guys diving with big humboldts report a lot of roughhousing and body-slamming, so at least on a jostle level it seems to be part of their behavior, but I think it's more full-body WWF moves than whacking with arms or tentacles.

I am waiting to hear Dr. O'Shea's opinion on this topic.....but I know he is probably a busy man:archi:

I'll point him this way. :smile:

The Mesonychoteuthis specimen in 2004 had no stomach (it had fallen/been torn out through a gash in the mantle, probably so the fisherman could recover his hand... KIDDING), so, no stomach contents. There is substantial anecdotal evidence of Meso munching on hooked toothfish but I don't think anyone knows whether this is its preferred/natural diet or whether it has learned that hooked fish are easy food.

Baby squid will certainly, and in fact prefer to, hunt shrimp and fish 100% to 150% of their own 'size' (= length), which they generally do at least with fish by striking at the back of the head/nuchal region, hanging on and munching through the dorsal tissue until the spinal cord is severed.

However, as is being discussed in another thread, even the colossal squid's esophagus is remarkably small (I would guess less than 1.5"/4cm diameter in adults) and passes through the brain, so other than the fact that hunting a single large prey item may require less effort than hunting multiple smaller prey items, there isn't much advantage to hunting ever-larger prey. Which of course doesn't mean that they don't.

How's that for helpful? :roll:

There is substantial anecdotal evidence of Meso munching on hooked toothfish
Are photos and video considered anecdotal? (Not being snarky, genuinely curious about the height of the threshold.)

Clem

I am waiting to hear Dr. O'Shea's opinion on this topic.....but I know he is probably a busy man:archi:

Stretched to capacity for the day I am afraid (thanks TTF). Will get back to this tomorrow, ok. Sorry.

Cool cant wait to hear.

Baby squid will certainly, and in fact prefer to, hunt shrimp and fish 100% to 150% of their own 'size' (= length), which they generally do at least with fish by striking at the back of the head/nuchal region, hanging on and munching through the dorsal tissue until the spinal cord is severed.




This is a somewhat wild thought, but if this is common behavior among baby squid (and I am certainly not doubting it), is it possible that there are crazy adults among the larger squid that seek to use the same technique against sperm whales, and are actually initiating encounters? It seems ludicrous, but so many scars seem to be found on the forward dorsal regions that it makes me wonder...

The thought is only wild, in as much that this type of behaviour would lead to a substantial opportunity of winning the Darwin award of the year in question, clearing the giant/colossal squid genepool of its least lamented protagonists. The difference in size and weight is a lot more than a mere 50% (up to 500 kg documented for Mesonychoteuthis and anywhere up to 60,000 kg for Physeter). If the whale does not make a clean kill first time around, struggling large squid can obviously lash out in a final attempt of self defense, or alternatively if the whale "misses", retaliate in mortal panic. Swimming away very, very quickly appears to me the behavioural trait best rewarded with apparent "fitness" and subsequent survival/offspring. :wink:

I'm with you on that, but there is the debate about Architeuthis' intelligence!

Stretched to capacity for the day I am afraid (thanks TTF). Will get back to this tomorrow, ok. Sorry.


Just a friendly reminder for our busy professor to get back to us and make a few comments on this topic.

Yes thx scott and another question how strong would you consider the colossal squids beak mr o shea?

Steve has been busy with whale strandings in NZ this week, so probably hasn't been online much.
In the meantime, there was some discussion of Mesonychoteuthis' beak here (http://www.tonmo.com/forums/showthread.php?t=12021), relative to that of Dosidicus.

Kat,
Back a week or two ago, Steve mentioned that he was afraid NZ was in for a bad year for whale strandings and you used the plural. Does his forecasted fear seem to be materializing?

I've lost track; one mass stranding thus far, and about 10 others in the space of a couple of weeks, single animals to 3 animals.

Not sure whether we're in for a 'bad' year for stranding. It could just be the time that these things happen and we are being notified more often.

I have been expecting a mass stranding near where we are, but it has yet to eventuate. Cross fingers that it doesn't happen.

ya I have heard about the strandings over there, best luck too ya Steve