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What do you regard as "safe" viz?

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Certified SCUBA Rider
May 7, 2002
Hi spearos.
What would you regard as the worst viz you would feel comfortable diving sharky spots in? lately i've been a lot more cautious when it comes to swimming out in dodgey viz. the only times i've ever seen sharks has been when its been pretty clean, so it makes you wonder what you dont see. from what i have experienced with shark behaviour (mostly reef sharks) is that they come in untill you notice them, then they dart off, keeping to the edge of viz. at the moment i'm not comfortable if there's a lot of activity like birds bombing, unless its about 10m. what do you think?
It's all relative... I would never dive in worse than 25 foot vis. before moving here... now 5 foot vis. is decent. :(
Hey Mark

This very question was on my mind today ! We went out to North Paw, off Clifton beach, on the yacht Esperance, and anchored about 70 meters from the rock. Viz was shitty, about 2 meters, but I took my gun anyway, and managed to shoot a Hottentot within 10 minutes.

Picture this now ! I am already a very wary, conservative spearo, I have just spent time in a cage with a Great White for the first time ever the previous week, and I had no buoy or stringer...so there I am, swimming 70 meters back to the boat in shocking Cape Viz, in the open ocean, carrying a bleeding fish on my belt.
Needless to say, it was a loooong swim home ! I have always said to myself I would never do that, but today, circumstances were such that I ended up there.
My stress-bells were ringing, but for some of my buddies, that was no biggie at all, so I guess 'safe-viz' is directly proportional to the size of your balls !!
bluecape, hows this for a definition. the viz you choose to dive in depends on the size of your balls!
i have been in some pretty scary situations. the worst was swimming into a shoal of redeye sardines, with viz less than speartip, and then watching a remora swim past. (insert brown wetsuit smiley) that was a long swim.
i realise that a certain diameter of goolies is required, but whats that saying about old, bold spearos?

fuzz, do you not get the sharks, or just dont see them?
Hi Griff,

Just for your peace of mind, shark eyes are much better at detecting motion and contrast than human eyes. They almost certainly see you well before you see them. The University of Miami (Florida, USA), years back, did some neat research with divers in the water, a high observation post and a sonic "shark call" that drew sharks from a long distance. The sharks would come straight in until they were just ouside visual range for the divers, then start circling. Often the divers never saw them.

I'm like you, spearing in poor vis makes me very nervous, but I suspect it doesn't make much difference to your chance of having an incident. Of the three times I've had really scary run-ins with sharks, the vis was 7, 10, and 50 meters. Visibility was a factor in the latter two cases but only because it gave me a chance to react, I don't think the shark cared. Of course, I don't have to contend with GW, that would sort of change the mindset.

Good luck and dive safe.
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San Francisco Input

Yep, this is a good thread, and has also been on my mind lately. A lot.

In fact it is on my mind everytime I get into the water here.

I recently moved to the San Francisco Bay area.

The vis here is generally pretty poor, on average about 5-10 m. Northern Califonria has few sharks by South African standards, but they do have Great Whites, and quite a large seal population, and statistically, they have a lot of shark attacks too.


The problem too is that shore diving here is very common, which I do because boat access is not easy, so there is no friendly boat to bail you out of the water quickly either. And I keep thinking to myself in my green picasso wetsuit, with my jubby little legs pumping away that I might resemble a fat seal, worse still a spastic one, to one of the whites. So basically, whenever I dive here, it is slightly unsettling, and it is hard to relax in these circumstances. Basically, compaired to diving on the Durban North Coast of South Africa, its an order of magnitude more intimidating and more scary. Perhaps this is a foolish illusion.

I spoke to one of the better divers round here, and he seemed to think that sharks where not an issue, and are rarely seen. But at the back of my mind I noted that because you can't see them, doesn't mean that they aren't there.

Now we can't change the vis, so the real question I had is if you are going to dive, how effective do you think a powerhead would be in this situation. Or do you think you shouldn't dive here at all. I dive with powerheads, but think that it is merely a safety blanket, and a hollow one at that, and the scary reality is that if a white wants to chomp me, I won't even see it coming, let alone have time for a powerhead.

Are there any other divers out there that dive in these conditions?I am interested in their views, and steps that they take to relax, when they dive, when they don't and that type of thing.
You're talking about my backyard here.

Viz-wize, yeah it gets lousy here, but then when it gets nice, it's really nice. I've seen it in excess of 80 feet. Three times. Not bad for 30+ years. :head

Shark-wise, I've seen Whites, had a seal taken in front of me by one and have been on large boats that were made veeery small when they'd roll over and give you the eyeball. But that's because I'm out here in the green a lot. You can ask a thousand others and their sightings add up to zero.

Still I don't make it easy on the big landlord. I don't dive the Marin County, Fitzgerald or Moss Beach in San Mateo, I sure as hell stay clear of Ano Nuevo and Greyhound Rock and only if it's unreal at Scott's Creek. I don't wear the fish if I can swing it, but... and I'm not a big fan of jumping into a bunch of seals in the surf. And I do not, as in DO NOT advocate the use or carrying of a bangstick, grenade, Glock or thermonuclear device here. The viz is the shits and it's going to be your luck to stick yourself, a rock, your buddy or a seal by accident or panic. I find that if you carry these things, you end up looking to use it. Better to dive in such a way as to leave the big boss his space and you go on your merry way. Way over there.

There are many other things that worry me more than a White out here, chief among them is me; then there's the other diver, the surge on that urchin-covered rock...
Originally posted by icarus pacific

And I do not, as in DO NOT advocate the use or carrying of a bangstick, grenade, Glock or thermonuclear device here. The viz is the shits and it's going to be your luck to stick yourself, a rock, your buddy or a seal by accident or panic. I find that if you carry these things, you end up looking to use it. Better to dive in such a way as to leave the big boss his space and you go on your merry way. Way over there.

There are many other things that worry me more than a White out here, chief among them is me; then there's the other diver, the surge on that urchin-covered rock...


That's some excellent thinking there and one of the best posts I've seen in a while.

I am fortunate to dive in an area where we don't generally get visits from the big boys, but we sometimes (seldom) hear about one lurking around.

Even though I don't spearfish, I occasionally end up in the water with spearos, sometimes in lousy vis.

As worried as I may get about what may be lurking in that murky water, you are quite right in saying that there are things far more likely to cause me trouble, so I just try and relax and hope I can find a convenient rock in a hurry if I have to:)

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agree with sven regarding the powerheads. in my opinion, if you have the time to stick it on your speartip, the shark isnt really interested in you anyway. especially the whites. i watched that documentory on air jaws in false bay, and there they say the sharks use the murk layer to stalk their prey, the seals, so if he wants you, you're not going to see him comming. also if you do have problems with a solitary shark like a great white, then i'm pretty sure that, if it comes to that, putting your spear into its head will be enough to put it off. i've heard of storys like that, but i've never heard of anyone putting a powerhead into a white. the only time i would consider using a powerhead is if you get mobbed by a pack of smaller sharks. the blacktips over hear can get very cheeky, or els those oceanic whitetips :(.

my question with viz comes down to the following theroy.
zero viz - shark bumps/bites you to see what you are
bad viz - shark comes very close before you see it
good viz- you have a better chance of seeeing the curious sharks
excellent viz - you dont ever get to dive, or you live on a tropical island, and i dont want to hear about it.

this applies to when the sharks are in curious mode. if they are pissed off, then the better viz gives you a chance to point your gun in the right direction.

another problem with bad viz is what you do with your fish once its been shot. i've been taxed before without even noticing, and thats with a 20m floatline :duh

Nice thread Griff

For Coastal island diving here the vis is usually 10-15ft but 10ft is what I would consider safe vis, I wouldn't even consider a shore dive here 90% of the year as you will not see you hand in front of your face :hm

Fortunately we dont get Great whites up this far North and if I lived in Sth Africa I would require 100ft minimum vis as safe vis with all those Whites around. We do however get Crocodiles and Tiger sharks. The "Crocs" sometimes come out of their natural habitats the estuaries and move along the coast and Islands looking for a new home and this is when they are dangerous to us, as I know of a local who got attacked but survived at one of the most popular spearfihing islands up here.


ps the only thing that draws us to 10ft vis is the Spanish Macks otherwise keep the throttle wide open and head offshore
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I am wondering how do you saw those macks and point your gun, aim it and pull the trigger in 10 ft vis?
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Shark attacks are rare along the Texas coast, and it's usually a bull shark in murky water full of mullet. Wade fishermen use a 20 foot stringer and regularly have their catch eaten by unseen, unfelt sharks. Along shore the viz is rarely more than a foot. When it clears up to 3 or 4 feet - just past the speartip- I dive around the jetties or groins. I get my fish into a bucket on the beach right away. Further offshore we have tiger and other sharks. I think I'd want 15 or 20 feet of viz out there to feel safe, and I'd get the fish out of the water.
I have enough problems with my polespear and slings to discourage the use of a bang stick. Maybe when I get out in the blue stuff.
Oh man ! ! ! You guys talking about 3-4 feet vis. and say its crap. You pray for 25-20 feet. In here if you see the rocks turbid in 15 meter below that what we call crap visibility:t

Anyway... I read that here will be held freediving comp. in 2004. May be you guys want to visit here. Especially i advise north part of the island. May be we can arrange few dive together :cool:
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Hi again guys

Just had 2 other things to add, firstly, to back up what Griff says, I spoke to the Great White research guys, and they all agree, powerheads are not going to help. If you see a white, he wants to be seen, and he's just passing thru. If he's interested in you, you wo'nt even know whats hit you. ( They're not known to 'bump'.) See attatched pic. ( False bay, shot by Chris Fallows.)

The other thing, people comment about Cape diving and whites, but it's not really that serious all the time, remember that most our dive sites have SERIOUS kelp forests to hide and hunt from...and that really helps with peace of mind. In short, bad viz is ok if shore diving in reefs and forests, but in the open ocean, it makes me nervous.
Swimming back to the boat off- shore with a bleeding fish in really bad Viz like I did yesterday was probably the dumbest thing I've done for a while...most times you get away with stupidity, but every now and again, someone does'nt. I wont get into that situation again. You can hunt in bad viz...provided you use common sense !


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Just a question?

This is an interesting thread.

What you are all saying makes a lot of sense, and the research and scientific angle is always appreciated. Thank you. In fact, a lot of what you guys are saying is in keeping with my understanding.

However, merely playing the devil's advocate here, the one question I had is, and I stand to be corrected on this, one of the most hardcore spearo's ever is Tommy Botha. He has one the SA nationals 9 times! In fact he has been attacked by whites twice. I am under the impression that he dives with Powerheads. The main reason, and I am not speaking on his behalf at all, so maybe we should get hold of him for his input, for this is that he has been followed back to the boat a few times and this is very intimidating. I don't know if he still does use powerheads, but he certainly used to dive with powerheads. Not only this, but I would argue, that the vast majority of experienced spearo's in the Cape dive with Powerheads too.

I would go further, and say not only are whites following divers back to their boats well recorded behavior, but the notion of being circled by a shark is even more likely when dealing with Tigers. They have been known to often cirlce around, and then attack, having been seen well in advance of any problems, and seemingly been rather docile, and having been known that they have been seen.

So the counter argument is this, the scientists are saying one thing, but it seems to be me that perhaps the most experienced diver, who is super hard core by any measure, and the guys with the most experience seems to be saying another thing.

How does one reconcile these two views ? i don't have the answers, and are not arguing one side over the other because your diving is your business, but when there is a large shark about, I prefer to put a powerhead on, and call for the boat. And if there is no boat, I am even more pleased to have the powerhead.

Can any of you guys from the Cape Chime in and tell us how many of the local guys use powerheads? Perhaps my info is incorrect ... wouldn't be the first time either.
You SA spearos have what we call down here in Miami "Cojones". Poor viz spearing in GW infested waters...shit you guys are "Cojonoos".


Regarding stupid things we do out in the water, I think it's safe to say that everyone commits a bone-headed move from time to time. The trick is to learn from it and not repeat it again. I speared a nice sized fish the other day with a salt-water croc in the vicinity all in 5' viz. When I got home that night, I told myself it wasn't worth the risk.

Good Luck to all you guys and beware of the tax collector in the grey suit:D
Hi Rat

I think my post may have caused confusion...on powerheads not helping, I was specifically referring to a situation where a great white decides he wants a piece of you...ie, you are not going to see him coming at all. I do however know of plenty of my buddies who dive with them, and certainly they are 'feel-good' things to have in a pocket should a shark be in the area and showing an interest. ( Not only whites.)
I will see if I can get Tommy Botha to write a piece for this thread if I can get hold of him, otherwise maybe Ed Hayman can do. ( Also had a run-in with a great white, and a massively experinced spearo. Was bent once by repeated deep freedives whilst spearing.
Great Idea

Blue Cape:

Thanks for your post. Yes, getting some input from the serious divers is the way to go, and I think it would be very helpfull for the other readers in this forum. If you could get hold of either of these guys (they used to dive commercially too, I think) it would be a really intersting piece of feedback. Thanks for the offer.

I will try and get hold of other chap who has a fair bit of experience with these monsters, he is an underwater camera man, and pretty hard core but a really approachable guy and always willing to give advice and assistance, and then we can compaire notes. He has some footage on his site here, if you want to check it out. If you look closely at his spear, I think it has a powerhead on it, but am not sure:


I can have my opinion, as can anybody else, but having never even seen a GW, I am not really in a position to speak with any authority really, and don't want to mislead people incorrectly in one direction or another. Having said this, Sod's law being what it is, the day I get convinced by you guys to ditch the powerheads, is the probably the day I get circled by a white and really get a good scare.
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My visibility limit is when it quits being fun. Either through fear of sharks or just not being able to see anything. One advantage of only diving from boats, is we can usually find clearer water, by going further out.
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Very cool thread. Am enjoying it much. Was diving at La Jolla a couple weeks back when the red tide was thicker, vis was about two foot on the surface, with about 15-20 foot vis at around ten feet down. tried to not even think the sh-rk word while recovering between dives. Any of you guys ever try one of those shark pods? The web site for them claims they have been throughly tested and found effective...if they really work(?) I would venture to speculate that that might be a more effective countermeasure in low vis than a bang stickas you wouldnt have to see the shark for it to work. Also wonder whether it would be effective in a case where a GW shark has selected his victim and is using a polaris attack( I beleive that is what it is called when they rocket up from below) I used to surf and dive the coast north of san fransisco and never saw a shark(although im sure they saw me).......and have no desire to!!
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