aggressive sharks on decompression stop

[AfterDark]

Many years ago I watched a documentary by Al Giddings. He left the safety of his cage to film several large great white sharks. His only tool was a pointy AL rod. When the sharks came close he poked them and they backed off and continued to circle him.
If I remember correctly he was managing 5 GW's with that stick. They did manage to maneuver him away from his cage by making their circles tighter behind him causing him to move forward away from the cage. He noticed and returned to the safety of his cage. I think he was the 1st professional underwater photog to do such a thing.
The shiny squares sound like a great idea as they get the shark away from you for a time. I'd use both if I thought I'd encounter potentiality dangerous sharks. I'd carry the squares and hang the stick on the deco line at the 1st stop.
I've only encountered one shark in 40 years of diving and it just swam by and kept going.

 

[T-Dog]

I am unable to find the article I am about to describe, which I read a couple of years ago. Perhaps someone else can find it. My memory is a little vague and I may not describe things accurately.

Dr. Richard Pyle is a famous ichthyologist and diver. He has had two very serious cases of decompression illness, both of which he openly attributes to "stupidity," if I remember his characterization correctly. The first was when he was young (19?) and just starting, but the other was when he was a very experienced diver. In the second case, he made a series of not-so-wise decisions on dives, probably pushing his decompression envelope to the limit. On his next dive, he was doing decompression while carrying fish specimens when some Galapagos sharks got more than a little curious. He had to make the exact decision you describe. In this case, it was not a safety stop--it was a real decompression stop with the knowledge that he had been pushing the envelope previously.

He decided to skip the stop.

He got seriously bent, but he is still alive and diving.

Here is the article I think you are talking about. Its a great read, and about a diver weighing the risks between sharks and deco.

http://www.dty.nl/bibliotheek/dieptestops/Confessions of a mortal diver II.pdf

 

[boulderjohn]

Here is the article I think you are talking about. Its a great read, and about a diver weighing the risks between sharks and deco.

http://www.dty.nl/bibliotheek/dieptestops/Confessions of a mortal diver II.pdf

That's the one. I originally read it (particularly the part about the danger of the posturing gray reef shark in the twilight-dark waters) just before my trip to Truk Lagoon (Chuuk), where all our twilight-dark stops were done in the presence of curious gray reef sharks.

 

[Angry Turtle]

... I'd carry the squares and hang the stick on the deco line at the 1st stop.
I've only encountered one shark in 40 years of diving and it just swam by and kept going.

if you dive in such environments, maybe that's another use for a foldable spear that I read about earlier in one of the lionfish threads

Foldspear - the holstered pole spear, spearfishing with polespear

 

[gotwake]

Now, we will probably have a new thread "dive knife, weapon or tool?"

 

[burna]

Non-galvanized sheet metal squares did not work ... it is suspected that is has something to do with the electrical field set up in the water.

If the shark is attracted to the electric field generated by the the death square sinking, couldn't they possibly be attracted to it while it is in your pocket??

 

[Dirty-Dog]

Many years ago I watched a documentary by Al Giddings. He left the safety of his cage to film several large great white sharks. His only tool was a pointy AL rod. When the sharks came close he poked them and they backed off and continued to circle him.
If I remember correctly he was managing 5 GW's with that stick. They did manage to maneuver him away from his cage by making their circles tighter behind him causing him to move forward away from the cage. He noticed and returned to the safety of his cage. I think he was the 1st professional underwater photog to do such a thing.
The shiny squares sound like a great idea as they get the shark away from you for a time. I'd use both if I thought I'd encounter potentiality dangerous sharks. I'd carry the squares and hang the stick on the deco line at the 1st stop.
I've only encountered one shark in 40 years of diving and it just swam by and kept going.

You know, I see/hear this from other divers as well. I guess either my wife or I must be some sort of shark magnet. We've only been diving since 2009 and have seen 1 Black Tip, 1 Gray Reef and 2 Nurse sharks. One of the nurse sharks came up and kissed the camera even.

 

[boulderjohn]

You know, I see/hear this from other divers as well. I guess either my wife or I must be some sort of shark magnet. We've only been diving since 2009 and have seen 1 Black Tip, 1 Gray Reef and 2 Nurse sharks. One of the nurse sharks came up and kissed the camera even.

It all depends upon where you go.

Please don't take this as one-ups-manship, but I have seen far more than that on a single dive. I would guess, in fact, that I saw at least 1,500 hammerheads in a 3-4 day stretch one time.

There are places that are full of sharks, and there are places where a single sighting is a wonder worthy of exalted talk after the dive.

 

[Jack Scuba]

This is an awesome thread to read before bed. Great links and comments!

 

[seaducer]

Experience has taught me that I'm more afraid of bubbles than sharks. .

For the most part sharks are more afraid of bubbles than you are afraid of them anyway...but there are exceptions.

Generally you can just push them away, with your best bet NOT using your hand, unless that is all you have. Even a big white can be easily intimidated if you have the cajones, since if you get a chance to see it, it is not really thinking kill. The one that wants you dead will come in fast from the backside.

If they arch their backs and point their pectorals down you are in serious trouble, since that is a sign of aggression, it may behoove you to skip a stop or two putting some distance between you and the shark. If the shark for some reason follows you displaying like this then take your chances with your decision, either way you are probably screwed. If it resumes a normal swim pattern or leaves, finish deco.

Sharks that are habituated to humans (even aquarium sharks are never trained or tame) will probably just ignore you or come in to see if you are going to feed them. These will probably scare the wet into your drysuit, but may in fact be fairly benign. Like the shark in that video in NC, never bit, or even looked like it was thinking bite. This was an animal that has learned not to fear divers, but it also knows people are freinds, not food.

Pelagic sharks at night are more worrisome, since they are more oportunistic in nature, while inshore species are more specialized in their diets. A white tip may need some real convincing that you are not dinner.