sharks, and thier behavior

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I found the link to the Shark "Shield" and "Pod" systems. One's bigger than the other.

http://www.sharkshield.com/howitworks.html

It has (surprisingly) more science and practical trials to it than I thought, and they obviously have done something to increase the range of electrical field reception. They have two videos of sharks supposedly repelled by the device. They're not what I would in any way call clear-cut, but anyone who has the moxie to face up to a great white like that must be either nuts or of great faith in the product.

I'm sure somebody on the board has used one or seen one used. Confess!
 
Ha ha chuckle, good comments regarding VT and television sensationalism, I quite agree, but shan't allow myself to get pulled into personality slagging here. Quite correct too those who've stood up for her, despite all, the Taylors did a tremendous amount to pubicise and promote diving worldwide and they deserve recognition for that.

That beside, I'm here to comment on the shark POD's asked about earlier. These were designed and developed by the Natal Sharks Board in Durban, South Africa, and I did personally spend some time test diving the units with them. I worked in conjunction with the Sharks Board as an independant scuba Instructor Trainer for a local dive operation who ran cageless shark dives for many seasons and was very active running shark orientation and education programs for local divers.

We found that the POD's had varying degrees of success with differing species of shark. For simplicity lets just say that the more aggressive the shark species the greater the effectiveness of the POD's repulsion ability. They are extremely effective against sharks like the great white, zambezi (bull) shark, tiger shark, etc, but seemed to have little effect on what we would term the harmless species like the ragged tooth (sand tiger). If you emailed the Natal Sharks Board directly I'm sure they would send you more scientific data.


kind regards

Dennis
 
dennisg:
Ha ha chuckle, good comments regarding VT and television sensationalism, I quite agree, but shan't allow myself to get pulled into personality slagging here. Quite correct too those who've stood up for her, despite all, the Taylors did a tremendous amount to pubicise and promote diving worldwide and they deserve recognition for that.

That beside, I'm here to comment on the shark POD's asked about earlier. These were designed and developed by the Natal Sharks Board in Durban, South Africa, and I did personally spend some time test diving the units with them. I worked in conjunction with the Sharks Board as an independant scuba Instructor Trainer for a local dive operation who ran cageless shark dives for many seasons and was very active running shark orientation and education programs for local divers.

We found that the POD's had varying degrees of success with differing species of shark. For simplicity lets just say that the more aggressive the shark species the greater the effectiveness of the POD's repulsion ability. They are extremely effective against sharks like the great white, zambezi (bull) shark, tiger shark, etc, but seemed to have little effect on what we would term the harmless species like the ragged tooth (sand tiger). If you emailed the Natal Sharks Board directly I'm sure they would send you more scientific data.


kind regards

Dennis

Dennis,

From the info I've found, shark attacks are roughly split 50/50 into 1) never saw it coming (shark saw a target and decided to strike) and 2) shark comes in and "looks around", maybe bumps the diver and then decides to attack.

Is there any research that would support the Shields effectiveness in #1, where the shark really is well into attack mode before they get within the range of the electrical field?

The videos mentioned above seem to support some effectiveness for #2 - the field discouraged the shark from thinking of the diver as possible prey.

Thanks.
 
I guess this should be obvious. If you are in the water, you should be aware of where you are and what is around you. If you are fumbling with your bcd midwater, you may look like wounded prey. Don't be surprised if you invite some unwanted company.

In my limited personal experience, I have found that sharks do not like people. I've also been told that sharks don't like the eye-to-eye contact. One of the guys at my dive club claims that if you want a good photo of a shark, you shouldn't look directly at a shark. As the shark swings around for a look, then you can look up and get a good shot.

Actually, I'm more worried about those giant grouper you run across. They can be territorial and mean as hell.
 
Well I'm not a scientist or marine biologist so I'm afraid I cannot provide your answers above to the level you are looking for. Try emailing someone at Shark Shield (info@sharkshield.com) and I'd hope they should respond with the appropriate level of information.

The POD's are very effective in any circumstance as far as I believe, as what happens is that the electrical field that the POD gives off (and it really does pump electricity into the water - I know as we got electrocuted a number of times before the Sharks Board got the levels right! chuckle) interferes with the electrical nervous system in the sharks body. The POD locks the shark into a muscle spasm, much like you getting a severe leg cramp, as long as it is within the zone of the electrical field emited by the POD. The shark rapidly turns away and learns its lesson. If it doesn't, well it'll just learn its lesson all over again! The problem with the POD's is that some people have been known to turn them off or don't wear them as directed, and consequently they tend not to have any effect. The old adage still applies: when all else fails, read the instructions! (chuckle).

I am curious about your statements of shark attack underwater (in previous threads). I've personally done hundreds and hundreds of open water cageless dives with most manner of beast. Admittedly, I have been bumped a few times, and seen a few odd reactions, but nothing that I would ever consider to be life threatening. Fair enough I'm probably comfortable tolerating a higher degree of risk that some (or have less brains than most - chuckle), but our confidence in shark diving comes from many many years of experience and a infinate understanding of shark behaviourisms. I'm certain that most peoples fear of shark is born from ignorance and lack of education or understanding of these beautiful creatures.

On Aliwal Shoal, off Durban South Africa, we continue to train entry level scuba divers through the thick of our shark season, and without exception our students come away in total awe and appreciation of their experiences. That said, it goes without say that the majority of Instructors and Divemasters that work this section of coastline are of exceptionally high standard and calibre. I have travelled and dived extensively worldwide, and patriotism aside, I have found few others worldwide that would match the standards these guys and girls have.

It is my personal belief, and the Sharks Board would hang me out to dry for saying so, that the POD's have little value for recreational diving. Why would you want to repell sharks that aren't dangerous anyway? It's difficult enough trying to get anywhere near them as it is. That aside please do buy one as South African business would be grateful for your investment (chuckle). I think their value lies with commercial divers or commercial shellfish divers etc, who are at risk of attack as they obviously have 'food' panicing around on their persons that would make for an easy meal for an opportunistic preditor. But remember it's not the diver that the shark is after, it's the easy meal that's being advertised to an open ocean.

To my knowledge, there's no reported incident of a sports diver being attacked by shark whilst underwater on scuba. The Sharks Board have found that all marine species are repelled by curtains of air bubbles and they in fact make an effective barrier to fencing out sharks, something the Sharks Board have been investigating to replace the controversial shark nets that are used worldwide. Hence the effectivness of purging your octo underwater should any shark approach too close for your own comfort, as mentioned earlier in the postings. And also as any underwater photographer will testify, breathing scuba is terrible for trying to get close to fish to take photos.

The danger in shark diving is always the time spent splashing around on the surface at the start and end of your dive, and it's thus the management of effective entry and exits (along with many other factors) that make shark diving safe or not. As I said, it all comes down to how good the people are who are leading and controlling your dive. This is strongly influenced by dive leaders who possess superior levels of knowledge, vast amounts of experience, global awareness of their surroundings, and a serious dedication to safety and professionalism.

If you've never shark dived with the big predators, boy are you missing out on the most exciting and memorable experience of your life. Get yourself to the Galapogos / South Africa / Mozambique / Australia / French Polynesia, etc - just get out there and see what magnificent awesome respectful creatures these are.


Happy diving
regards

Dennis
 
dennisg:
To my knowledge, there's no reported incident of a sports diver being attacked by shark whilst underwater on scuba.
The shark attack site lists 23% (out of 388 total!) occurring on scuba divers, but doesn't note if they're "sport divers" or not. There's another statistic that reports 26% of victims were NOT engaged in fishing activities, but that's the combined total for scuba, hookah, free divers, snorkelers, and sundry (354 incidents total). What was Rodney Fox doing when he got attacked?

I'm not sure if shark feeding activities constitute being "unprovoked." They should have been listed as a distinct subset if they were. In any event most of the attacks were caused by a lone shark without others nearby, and the biggest fraction (40% or a whopping 86) were from great whites.

All these stats I believe were within the last 182 YEARS. Yes, YEARS. I wonder how many can be attributed to the Indianapolis...
 
dennisg:
I am curious about your statements of shark attack underwater (in previous threads). ... I'm certain that most peoples fear of shark is born from ignorance and lack of education or understanding of these beautiful creatures. Dennis

Bingo! My fear is completely born of ignorance – that’s why I’ve asked all these questions. As a newer diver who is diving with his daughter I think I’m a bit on the cautious side until I understand as much as possible. We dive in the Pacific Northwest with infrequent warm water trips (going to Maui next week). We’re newer to diving so I’ve got a bit of the “What I don’t know just might hurt me (and more importantly my daughter)”.

Thanks, Dennis, for taking the time for such a detailed response.
 
I agree! There's far too much hype about shark attack and I think a lot of confusion is caused by the inaccurate way that attacks are reported. I appologise I don't know who Rodney Fox is, but I guess on a similar note, a scuba Instructor recently died at Sodwana Bay in South Africa.

The press went to town as they do (in their manner of creating sensationalism to sell more of their papers) cleverly mixing words like scuba/diver/shark in the same sentance leaving the impression on a non-diving mass that a scuba instructor had savagely and aggressively been attacked and eaten by a large tiger shark to the extent that only his one hand was recovered. Although I have no place to comment on the events of an unfortunate incident, deeper investigation would appear to reveal that he was actually spear-fishing no where near any of the dive reefs, and had suffered shallow water blackout a few days previously. It's been suggested that he might have blacked out again this time as he failed to surface and wasn't seen by his buddies. OK, so we have a spearfisherman laying on the sea bed with speared fish on or near his person?

Following an aerial search a large Tiger shark was 'seen in the area', and apparently the dive team found the guys hand. Of course, follow up reports where not published in the press to any full extent, and the record remains in people's minds that a scuba instructor was killed by a dangerous tiger shark in an unprovoked attack at a popular dive destination, and therefore it must mean that scuba diving is extremely dangerous. What rubbish! And how typical of the press!

Of these statistics mentioned above regarding attack on 'scuba divers' it would be interesting to know how many of those occured unprovoked whilst underwater and how many occured on the surface perhaps at the end of a dive, which would make complete sense.

Again my comments on great white attacks: other sharks have a similar tooth structure to the great white (the zambezi/bull shark has the same upper tooth structure). It seems that worldwide whenever there's a shark attack, what ever species it might have been, the press immediately goes to print frequently without justification about another killer great white. Thanks Mr Spielberg!

My advice: if you get to see a shark whilst diving, consider it that you have just witnessed a special event in your life. It's an awesome experience, and not one that you will forget soon. In my experience I have found sharks to be extremely shy on the whole and most shark sightings are of the tail end as they are shooting out of the visibility zone. Sharks are not aggressive man-eaters as the press will have us believe, and they will not come looking for a fight unless they are being provoked, cornered, or put into an eating frenzy because you're teasing them with fish products.

There, that's my 5 cents worth. Boy, this is fun!

UWSojourner, I hope you didn't take any offense at my use of the word 'ignorance', as none was intended. You're completely correct, what you don't know can harm you sometimes, and you're absolutely correct to ask the questions. As an Instructor I always encourage people to live their lives to the full. Risks CAN be taken, it's how we grow, expand, and develop, but risks must always be calculated to be within your own zone of comfort and capability. Sometimes, you HAVE to leave your comfort zone to achieve success in life. Live a safe, predictable life, and you will never know just how extra-ordinary you really are and just what a great life this is that we have to enjoy. Lucky you going to MAUI next week, I hope you have a great time. Happy safe diving!


kind regards
Dennis
 
dennisg:
I agree! There's far too much hype about shark attack and I think a lot of confusion is caused by the inaccurate way that attacks are reported. I appologise I don't know who Rodney Fox is, but I guess on a similar note, a scuba Instructor recently died at Sodwana Bay in South Africa.

The press went to town as they do (in their manner of creating sensationalism to sell more of their papers) cleverly mixing words like scuba/diver/shark in the same sentance leaving the impression on a non-diving mass that a scuba instructor had savagely and aggressively been attacked and eaten by a large tiger shark to the extent that only his one hand was recovered. Although I have no place to comment on the events of an unfortunate incident, deeper investigation would appear to reveal that he was actually spear-fishing no where near any of the dive reefs, and had suffered shallow water blackout a few days previously. It's been suggested that he might have blacked out again this time as he failed to surface and wasn't seen by his buddies. OK, so we have a spearfisherman laying on the sea bed with speared fish on or near his person?

Following an aerial search a large Tiger shark was 'seen in the area', and apparently the dive team found the guys hand. Of course, follow up reports where not published in the press to any full extent, and the record remains in people's minds that a scuba instructor was killed by a dangerous tiger shark in an unprovoked attack at a popular dive destination, and therefore it must mean that scuba diving is extremely dangerous. What rubbish! And how typical of the press!

Of these statistics mentioned above regarding attack on 'scuba divers' it would be interesting to know how many of those occured unprovoked whilst underwater and how many occured on the surface perhaps at the end of a dive, which would make complete sense.

Again my comments on great white attacks: other sharks have a similar tooth structure to the great white (the zambezi/bull shark has the same upper tooth structure). It seems that worldwide whenever there's a shark attack, what ever species it might have been, the press immediately goes to print frequently without justification about another killer great white. Thanks Mr Spielberg!

My advice: if you get to see a shark whilst diving, consider it that you have just witnessed a special event in your life. It's an awesome experience, and not one that you will forget soon. In my experience I have found sharks to be extremely shy on the whole and most shark sightings are of the tail end as they are shooting out of the visibility zone. Sharks are not aggressive man-eaters as the press will have us believe, and they will not come looking for a fight unless they are being provoked, cornered, or put into an eating frenzy because you're teasing them with fish products.

There, that's my 5 cents worth. Boy, this is fun!

UWSojourner, I hope you didn't take any offense at my use of the word 'ignorance', as none was intended. You're completely correct, what you don't know can harm you sometimes, and you're absolutely correct to ask the questions. As an Instructor I always encourage people to live their lives to the full. Risks CAN be taken, it's how we grow, expand, and develop, but risks must always be calculated to be within your own zone of comfort and capability. Sometimes, you HAVE to leave your comfort zone to achieve success in life. Live a safe, predictable life, and you will never know just how extra-ordinary you really are and just what a great life this is that we have to enjoy. Lucky you going to MAUI next week, I hope you have a great time. Happy safe diving!


kind regards
Dennis

No offense at all on the use of "ignorant" - actually it is very appropriate as it just means a lack of education or knowledge which is exactly where I'm at right now, but getting better.

"Live a safe, predictable life, and you will never know just how extra-ordinary you really are and just what a great life this is that we have to enjoy." Well said ... I may have given the impression that I'm totally risk ADVERSE. Not so. I'm more into risk control - especially if I'm responsible for someone else. (Which is really another post since, in reality, I'm her buddy but I don't really believe at this stage that she's mine. Somehow I've got to encourage her to take ownership of the dive. She sets up her own gear and is actually vary cool headed - she called a dive once because she was uncomfortable - but I think she's a bit dependent on the "hey, Dad's with me" mindset.) Anyway, rambling ...

Thanks for your time.
 
May i go the opposite route on the topic.

How may we attract sharks (white tip, black tip, nurse shark) to a location say 110 ft deep by reefs edge?

:eek:)

paolov
 
https://www.shearwater.com/products/teric/

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