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Largo
02-27-2012, 19:00
There is a lot of 'information' out there regarding shark behavior.

I was just wondering what you have learned about shark behavior, (by species)
during your diving career.

My shark experience is very limited. I've only seen them in the wild, on a handful of occasions.

The species were; Sand Tiger (once, fleetingly), Sand Bar, Nurse, and either Caribbean Reef or Blacktip Reef (possibly both, I have a hard time telling them apart).

Sand Tigers are shy. Sand Bars are territorial and like small coves. That's all I know.

navyhmc
02-27-2012, 20:20
1. Don't mess with them and most of them won't mess with you. Which is why I'm NOT a fan of the shark feeding dives.
2. There are more of them around you than you can see.
3. Most reef sharks are interested in food a lot smaller than us so you're safe-unless you're bleeding.
4. Watch their body language: A shark doing an exaggerated side to side motion with fins almost straight down is royally pissed off and probably going to attack something or someone and it might be you.
5. Great Whites, Makos and Tigers scare me! But I found Jaws funny as all hell.

AfterDark
02-27-2012, 23:14
I've only been in the wild (that I know of) with Atlantic Sand Tigers, and one time a Blue shark swam by me but kept going, had it swam by 20 feet away instead of the 10 feet it did I wouldn’t have seen it at all. I’ve learned from books, internet, and TV, NOVA, NATGEO…….. Most sharks have fish teeth that is teeth designed to hold and eat fish. Those sharks can give us a nasty bite(s) and big ones can inflict fatal wounds. They are normally not attracted to the smell of human blood but sounds and sight can incite a bite. Sharks like Makos and GWs have fish teeth when young then grow marine mammal eating teeth as they grow, and they grow BIG. Those teeth can slice through fat, muscle and bone pretty much equally. Thier bites are often fatal. They are all wild animals and are unpredictable and dangerous, as well as graceful and beautiful. I wouldn’t be crazy about hanging out in the open water with GW’s and the like; but those Sandies sure seemed like well behaved animals. They do know the difference between a gloved hand and a bare one by the touch.

The way the sightings of GWs have been increasing around Cape Cod and other areas close by I figure it's only a matter of time until I meet one.

Smashee
02-28-2012, 00:09
There is a lot of 'information' out there regarding shark behavior.

I was just wondering what you have learned about shark behavior, (by species)
during your diving career.

Always look out for unexpected wobbegongs. They're pretty placid, but they have excellent camo and if provoked enough, will tend to bite & hang on.

To prevent sightings of larger & more impressive looking sharks, carry a camera with you.

PlatypusMan
02-28-2012, 09:25
To prevent sightings of larger & more impressive looking sharks, carry a camera with you.

Spot on!

Lulubelle
02-28-2012, 12:46
I dive a lot with Sand Tigers. Loads of Sand Tigers. They are very mellow, and they have never harmed me or scared me in the least.

Personally, I am not afraid of sharks. I am afraid of people as their track record in my life is not so good.

This is what I know.

Seniordiver
02-28-2012, 13:10
I recently encountered a large nurse shark (7-8ft) sleeping in a cave off Cozumel. A number of the group wanted pictures and kept at it until the shark woke suddenly, and came screaming out of the cave in a panic:can't blame it-I would react the same if I suddenly woke up to find strange creatures in my bedroom taking flash photography. In any case it headed directly at a nearby diver who fended it off with his hands-gave him a hell of a scare!

Do let sleeping dos/sharks be

FFDiver
02-28-2012, 15:14
Just watch Jaws and see what happens... It seems like most sharks dont bother people but I dont have any experience with them to say so from a factual standpoint. So at this point I will just try to avoid them.

Clernix
02-28-2012, 16:05
I have been diving so much in Coz over the past years that I miss seeing them. I plan to take a trip on a BB cruise next year to hopefully get my fill.

I dove a lot in the Maldives and saw alot of white and black tips. They always kept their distance and were the highlight of the dive. Had a couple run ins with tigers and they make me nervous. They are higher on the food chain and they know it.

bottomdweller
02-28-2012, 16:10
My wife won't let me keep one in the bathtub.:smiley19:

navyhmc
02-28-2012, 16:23
I have been diving so much in Coz over the past years that I miss seeing them. I plan to take a trip on a BB cruise next year to hopefully get my fill.

I dove a lot in the Maldives and saw alot of white and black tips. They always kept their distance and were the highlight of the dive. Had a couple run ins with tigers and they make me nervous. They are higher on the food chain and they know it.

I'm glad I'm not the only one who thought that: I was in Coz in '85 and saw a lot of reef and sand sharks. The last time I was in Coz was on a cruise ship stop and did a semi-sub with the family and didn't see one. I was depressed. I didn't see a one on my last trip to Roatan either.

DiveHard
02-28-2012, 16:44
My limited experience with "seeing" sharks came on a handful of dives off Jupiter FL. Bulls, Reef and some Blues. One medium sized reef swam directly under my GF without her even noticing. I DID.. Hehe

Their behavior can change in a blink of an eye. One moment they are casually swimming about, the next darting in all directions with their fins out straight. This change happened when a near by spearo shot at a fish. He did not even hit the fish.

I would argue they know the sound of the boats that spearo use and their guns. The analogy of "Don't feed the wildlife" is a good one to heed. Entering the food chain on a different level is bad enough. Wise not to include ringing the dinner bell IMO.

We were told by the boat Capt not to remain on the surface or stir up the bottom. Could stay off the bottom but had to wait 15min on the surface to get picked up from the drift dive. My eyes were glued to the water below.

scubajane
02-28-2012, 17:23
you are more likely to be killed by a vending machine than by a shark

nurse sharks and zebra sharks are rather mellow still don't 'mess' with them

when we dive the aquarium the zebra sharks find us interesting and swim close to us and actually rub up against us like a cat would

We saw the handlers at the zoo remove a zebra shark from the water to weigh her. she was not quite prepared and whacked the handler with her tail across his back lots of screaming and splashing huge tail shaped welt on the handler's back it knocked the stuffing out of him

the bamboo sharks hide alot they are in the tank but I've only seen them 2 times

Largo
02-28-2012, 18:52
It's rare to even see a shark.
Speaking of which, I've seen hammerheads in the gulf, but from the window of a tall building. But, I've never seen one while diving.
They must just take off when the dive boat arrives at the artificial reef.



What's the big attraction to shark fin soup? Can't people be satisfied with rotisserie chicken and some fries?

scubajane
02-28-2012, 20:25
we should call the Japanese and tell them that Atlantic lionfish is a much better aphrodesiac than shark fin soup

navyhmc
02-28-2012, 21:04
I like that idea Jane. Better yet, concvince them that contrary to popular belief, Shark Fin Soup is quite the opposite of an aphrodesiac.

DevilDiver
02-28-2012, 21:29
What's the big attraction to shark fin soup?


A study published in the journal Marine Drugs (http://www.mdpi.com/1660-3397/10/2/509/) links the consumption of shark fin and shark products, including dietary supplements, to neurodegenerative diseases in humans including Alzheimer’s and Lou Gehrig Disease. This is due to the presence of high concentrations of a neurotoxin called BMAA in the shark products. The study was carried out by scientists from the University of Miami, and is reported on the Rosenstiel School of Marine and Atmospheric Science's blog (http://www.rsmas.miami.edu/blog/2012/02/23/new-study-shows-alarming-accumulation-of-bmaa-neurotoxins-in-shark-fins-which-may-pose-a-serious-threat-to-shark-fin-consumers/). Most significantly, the study suggests:

"That consumption of shark fin soup and cartilage pills may pose a significant health risk for degenerative brain diseases."

AfterDark
02-28-2012, 23:02
A study published in the journal Marine Drugs (http://www.mdpi.com/1660-3397/10/2/509/) links the consumption of shark fin and shark products, including dietary supplements, to neurodegenerative diseases in humans including Alzheimer’s and Lou Gehrig Disease. This is due to the presence of high concentrations of a neurotoxin called BMAA in the shark products. The study was carried out by scientists from the University of Miami, and is reported on the Rosenstiel School of Marine and Atmospheric Science's blog (http://www.rsmas.miami.edu/blog/2012/02/23/new-study-shows-alarming-accumulation-of-bmaa-neurotoxins-in-shark-fins-which-may-pose-a-serious-threat-to-shark-fin-consumers/). Most significantly, the study suggests:

"That consumption of shark fin soup and cartilage pills may pose a significant health risk for degenerative brain diseases."


Chicken or the egg?

moosicman
02-29-2012, 00:52
My limited experience with "seeing" sharks came on a handful of dives off Jupiter FL. Bulls, Reef and some Blues. One medium sized reef swam directly under my GF without her even noticing. I DID.. Hehe

Their behavior can change in a blink of an eye. One moment they are casually swimming about, the next darting in all directions with their fins out straight. This change happened when a near by spearo shot at a fish. He did not even hit the fish.

I would argue they know the sound of the boats that spearo use and their guns. The analogy of "Don't feed the wildlife" is a good one to heed. Entering the food chain on a different level is bad enough. Wise not to include ringing the dinner bell IMO.

We were told by the boat Capt not to remain on the surface or stir up the bottom. Could stay off the bottom but had to wait 15min on the surface to get picked up from the drift dive. My eyes were glued to the water below.

Yep, it is the sound of spears not the boats (unless it is a popular shark feed dive stop, then they come to the boats and the anchor chains). Just the zing sound of the speargun will almost guarantee that any in the area come to investigate even if nothing is shot.

Dead things float, which is one reason why surfers, swimmers, paddleboarders, and snorkelers are the overwhelming bulk of attacks that are unprovoked (that and the fact that at dusk and dawn bait fish tend to run in shore). Look through the ISAF and you'll see that unprovoked attacks on scuba divers are INCREDIBLY rare. Overall percentage chances of an attack are in the single digit rhelm and then of those attacks, unprovoked attacks on scuba divers are even less. The above instance about the sleeping beauty Nurse would qualify as a "provoked attack".

Bulls and Tigers are to be regarded with great caution. No animal on the planet has more testosterone that the Bull Shark. This is why they have such a welcoming and sunny desposition (not). They are very territorial so it is wise when they are seen not to advance toward them as they can recognize this as an act of aggression. Likewise, a quick retreat can trigger a "flight" response attack (like running from a threatening dog that then wants to assert its dominance). Still, these are just wise guidelines; under normal circumstances they'll just pass you by if there is no activity to cause them to investigate.

Tigers are just the indiscriminate trash compactors of the ocean. Plus, they can be just as docile and lethargic in attitude and body language and you'd never see an attack coming until it is too late. Additionally, what makes them so dangerous is that unlike other species (even Great Whites), they don't bite and then leave you alone, realizing you aren't actually on the menu. They are just as apt to return and finish the job. Again, they are indiscriminate in what they eat. Their size makes them able to do more damage per bite than say a small reef shark. So they bear much respect.

One species that hasn't been metioned and should probably replace the aformentioned Make (short-fin) in the fear category is the Oceanic White Tip. As a pelagic shark it needs to eat at every chance it can find a meal and so is a bit of a scavenger. Food is not always at the ready in the open ocean so when they come in shore or to reefs they take advantage and can be very territorial and aggresive, almost an equal to the Bull (but not quite).

The Great White has its reputation legitimately but may be a bit inflated due to that it just looks like something to be feared (until you get to know them, then they go from fearful to beautiful and awesome). But with the Great White, they feed so frequently in places that humans go to hunt or play so its kinda like a kid playing in the road - eventually there's going to be a few "incidents". They are also ambush hunters which adds to their level of danger and you most likely wouldn't know what hit you until it did (rest assured that they know you're there long before you know they are). Their size makes even an investigative bite a mortal wound, though unlike the Tigers, they usually bite and retreat and do not consume. Fortunately, they like the cooler climate so stick to the tropics and chances of running into them by accident are almost nil.

People are always scared of the Makos and Hammerheads but it is rather unfounded. I myself tend to be leary of the Mako but that is because it just looks a bit vicious and is SO FREAKING FAST. Though I (we) fool ourselves into thinking we are fish-like and can manouver in their environment with as much ease as they can, the truth is that they've got the upper hand and we are actually like hobbled horses at a severe handicapp even at our peak. But the Makos move like squirrls due to the muscular/skeletal build of their tails (it is different than that of all other sharks and fish as it is more piston-like in movement - I think similar to the dolphin and porpoise) and it makes them one of the fastest sprinting fish in the sea. Having said all of that, there are very, VERY few attacks on divers in the totaly history of the ISAF's records from Makos and I don't think there is ANY recorded attack on humans from Hammerheads but if there are it is only one or two.

I rambled but I'm a shark NUT so it got me going.

Hey DiveHard, what part of FL gulf coast? I'm in PCB.

DiveHard
02-29-2012, 11:06
:moosicman

I live in the New Port Richey area. (Pasco County) About a mile inland from the Gulf.

Largo
02-29-2012, 21:23
A study published in the journal Marine Drugs (http://www.mdpi.com/1660-3397/10/2/509/) links the consumption of shark fin and shark products, including dietary supplements, to neurodegenerative diseases in humans including Alzheimer’s and Lou Gehrig Disease. This is due to the presence of high concentrations of a neurotoxin called BMAA in the shark products. The study was carried out by scientists from the University of Miami, and is reported on the Rosenstiel School of Marine and Atmospheric Science's blog (http://www.rsmas.miami.edu/blog/2012/02/23/new-study-shows-alarming-accumulation-of-bmaa-neurotoxins-in-shark-fins-which-may-pose-a-serious-threat-to-shark-fin-consumers/). Most significantly, the study suggests:

"That consumption of shark fin soup and cartilage pills may pose a significant health risk for degenerative brain diseases."


That's a great post. Thank you.

PyrateDiver
03-01-2012, 16:00
we sawca six foot nurse last time in coz, about 20 feet from us, seemed to care less about us and swam on by