Question...

[saildiver]

Well, my guess is that the oceanic white tip (the only blue water species I can really think of) would have to be more oppertunistic and aggressive simply because it lives in such a nutrient-poor enviroment. When you go weeks without seeing another living creature, a shark would probably try to take whatever it can get. That's just my compleetely uneducated guess

That's generally correct Mantascareme-but its not that simple-because some of the bigger sharks are also likely to travel long distances...ie,Great Whites tagged in California were recently spotted in Austrailia-so they swam across blue water to get there. Tigers,Great Hammerheads,Makos, and Bronze Whalers, all are also felt to "migrate " over large expanses of ocean. Throw in the other " Pelagic" species that we've not talked about much-Blues,Threshers-I'd generally say that you are generally safer near the coast(depending which one) ...again rest easy-scuba diving is really quite safe in regards to the shark concern,unless you dive with Great Whites...Peace...Saildiver.

 

[gcbryan]

Not scientific but on the show "Myth Busters" they put one drop of fish blood in a tank with some type of small sharks and they reacted immediately. When they put several drops of human blood there was no reaction at all.

No scientific conclusions to be drawn here but interesting nevertheless.

 

[Jedi]

A simple rebuttal is that the sharks didn't have the prior experiance necessary to equate the smell of human blood with food.

Fish blood though, they know what that means.

Find a shark that has tasted human blood before in it's life and see what the reaction is.

 

[Ishie]

Find a shark that has tasted human blood before in it's life and see what the reaction is.

Probably "Blech, those things are covered in rubber, sometimes adorned with metal or holding big boards all for a meal that has the relative fat content of a chicken bone. On the other hand those things sometimes catch fish, saving me the trouble, and are usually more than happy to give it up if I look mean."

I could be way off, but wasn't the assumed culprit in the Indiana blue sharks? I thought that though generally not really prone to attacking humans, in certain circumstances, they will get into feeding frenzies by the thousands, where they really will eat anything. I think they do this with the huge squid runs, but heard that this could be an explanation for losing that many people over a relatively short period of time while some people lost at sea have been so for days without ever seeing a single shark, whether they're bleeding or not.

On shark week last year, though it wasn't days, they showed the National Geographic photographer that got swept away in the current and ended up several hours off Darwin in the Galapagos. She had a video camera, and had surfaced when there were a few too many Galapagos sharks. Upon surfacing with no sight of boat or land, she had a brief panic attack. What's interesting is that while she was thrashing (and the camera was thrashing), you could see the sharks start to come up to investigate, but when she shrieked (though I don't think she'd seen them yet, just the camera attached to her hand), the closest shark clearly looked startled and jetted back down.

Once she regained her wits, she swam against the current back to Darwin with the sharks schooling under her the whole time, and nothing. She ended up fine, except for getting a bit beaten up trying to get onto Darwin.

 

[Jacqueline]

I would not dismiss the GW as a predator of man. A recent article in sharkattacks.com documents a case where a 34 year old wife and mother was vicously attacked by a gw while in the ocean swimming in less than 5 ft of water, and the gw obviously had a taste for human blood - it resurfaced to eat her limbless torso after tearing her to shreds and killing her, and the woman's husband and another couple helplessly saw this whole thing! The woman was swimming alone - no one else near her in the water. This occurred in Australia. So much for humans not being a chosen palatable meal for gw's! The only thing a gw may shy away from attacking is an adult orca. I also read an article at this same site that documented a case of a gw head-butting or ramming a tourist boat off the Massachussettes coast. No one knows why the gw rammed the boat. It was a tourist boat - not a commercial fishing boat. Once I get through the preliminaries and am ready for my first OW dive as a student, I certainly will not choose to go on a dive in gw dominated regions if I can help it. I want to understand a little more about an environment before I enter it.

Makos are the acrobats of the ocean....and are also bullies (they won't let any other sharks join in their sharky games ), presumably because they want to show everybody else in the water that it is THEIR turf. Makos have on occaison attacked humans - presumably to "show them who was boss" when humans were near the Mako's food or a potential mate which the Mako allegedly percieved the human as a threat to its turf, its food and competition for the female Mako nearby. Makos have also been known to run off gw's - again, to show who was boss. Makos really are beautiful creatures whose jumps and mid-air twirls at 20 ft up out of water really make the notorious jumping Marlins look like stumble-bums! Growing up an ocean rat on the eastern seaboard, I probably was swimming among Makos without knowing it when I rode the rip currents all the way out for fun (about 1 mile from shore) and swam back inland, with the aid of incoming currents and waves rolling in. Makos do frequent the Atlantic.

Tiger sharks are omnivores and opportunistic feeders - and so are bulls. I don't want to provide those guys with any opportunity to taste-test bite me! They might be timid of divers under the water, but what about when the diver surfaces - especially if it takes them a few minutes to get back to the boat? Isn't that ample time for a shark to "mistakingly" bite off a diver's legs? What can be done to minimize this danger to divers?

 

[Rocha]

Great whites eat mammals. Humans are mammals. Therefore, Great whites eat humans.

Most other sharks won't eat man flesh, it is even common to find the body parts that were bitten off after the attack. The exception is the Tiger shark, which will also eat license plates.

 

[Jacqueline]

Most other sharks won't eat man flesh, it is even common to find the body parts that were bitten off after the attack. The exception is the Tiger shark, which will also eat license plates.

Even if the other sharks leave the bitten-off body parts and did not eat the person, that still isn't good for the bite victim - they are STILL missing their arm or leg. Not a pretty prospect.

 

[Rocha]

I know, and I am not saying that it is nice to have an arm bitten off, what I am saying is that they won't try to attack if they are well fed. Humans are not their prey and they often don't like human flesh after they try it.

On a side note, here is a short list of animals that kill more humans per year than sharks:

crocodiles
elephants
bees
dogs

Not to speak of plane crashes, car accidents, lung cancer, slippery bathroom floors, etc.

 

[Tiggs]

USS Indanapolis is an odd example to use...........no one knows how many of the saliors died from exposure/wounds before being attacked by sharks (maybe thats why they didnt show up til the next day)

once there were dead bodies floating in the water its got to be a different story.....sharks will eat a Blue Whale carcass...but i doubt they kill many!

I would rather be swimming on a reef with a big scary shark that floating in open ocean with loads of dead bodies around me and lots of little sharks.

T

 

[Ishie]

Also, from what I've been reading recently, African lions have been taking out a fair number of people, with a far higher mortality/attack ratio.

In a few attack cases with GWs, there is somewhat mystifying behavior in which a shark appears to deliberately target a human. This makes up a very small percent of attacks. Though not great for the victim, the GW model is bite once and then whether the vic makes it to shore from there is a matter of luck. They have, I believe, a 60-75% chance of making it.

In the few cases where a human has been deliberately targeted, unless, as I've seen in one case, there is a boat RIGHT there to yank them out of the water before the shark makes a deliberate run, the human has essentially no chance.

While that's disturbing it makes more of a case for us not being part of their regular diet. If we were, they'd be killing us in droves. Think of how many humans a day a 15' GW could take out, and yet, we have maybe one fatality a year for all the people who go in the water, and the fatalitiy is usually a single-bite case where the first bite was too devastating to be survived, as was the case with the abalone diver who died last year and the woman swimming in San Luis Obispo, I believe, in 2002?