Damage to marine animals eyes by strobes.

My dad was there when that manatee came down!

Personally I cannot see (excuse the pun) how it wouldn't effect the subject, especially those used to a darker environment, it must be a bit of a shock to be flashed once if you are not expecting it let alone an onslaught of flashes... If scientific study concludes that flashing 'high powered lights' into the eyes of your subjects causes stress or worse will the shooters cease to use them??? Dive safe

 

DeanB

Probably not. But, it may encourage them to take fewer-more thought out-photos instead of the spray and pray approach we see so often. I will, usually, take around three careful shots and then go to the end of the line before trying again. If there is an onslaught, I will stand on those few exposures.

Subject: Likelihood of Damage to marine animals eyes by use of strobes.

 

I've written an article about this based on my own long experience photographing animals with up to 40,000joules of strobe. (A typical underwater strobe delivers a lot less than 100joules).

 

I also got the opinion from a distinguished professor in animal welfare - but he is my brother!

 

My editor would like to add the opinion of some independent marine biologist that has made a proper study (with a control group) of this. Do any of you know of such a study or such a marine biologist?

 

Thanks.

John -

It is entirely plausible, if not likely, that prolonged exposure to intense light could result in retinal degeneration - this has been demonstrated in some strains of mice.

I do know a few world-class veterinary/comparative ophthalmic pathologists, if you should ever wish to pursue this as a true clinicopathologic study.

John -

 

It is entirely plausible, if not likely, that prolonged exposure to intense light could result in retinal degeneration - this has been demonstrated in some strains of mice.

 

I do know a few world-class veterinary/comparative ophthalmic pathologists, if you should ever wish to pursue this as a true clinicopathologic study.

Would it be plausible that the Emperor dive-guides were right in trying to ban people from using strobes?

Should we be discouraging wetpixellers from shining lights/strobes at marine animals?

Now there's a thing to consider......the combination of focus light use AND strobe flash ...simultaneously...

And video lights?

JB,

where are you going with this?

If your findings are that strobe, video, focus and lamp lights are / are not detremental to the wellbeing of marine life, are you going to put that in print?

Without solid scientific evidence either way you'll leave youself open to a feeding frenzy.

I think you've been handed a poison chalice by Mr Weinman.

Nige

JB,

 

where are you going with this?

If your findings are that strobe, video, focus and lamp lights are / are not detremental to the wellbeing of marine life, are you going to put that in print?

Without solid scientific evidence either way you'll leave youself open to a feeding frenzy.

I think you've been handed a poison chalice by Mr Weinman.

 

Nige

Sometimes someone has to take the stance if new findings show old practices to be wrong ... Some subjects are not going to win you friends if it goes against the grain, so to speak, however if it protects the animals in focus then who cares what the selfish humans think. Are we not here ultimately to promote their well being, so if we have to make sacrifices so be it ...

Dive safe

DeanB

Sometimes someone has to take the stance if new findings show old practices to be wrong ... Some subjects are not going to win you friends if it goes against the grain, so to speak, however if it protects the animals in focus then who cares what the selfish humans think. Are we not here ultimately to promote their well being, so if we have to make sacrifices so be it ...

 

Dive safe

 

DeanB

Dean,

I couldn't agree more,

I just want to protect my old friend from being vilified in the diving press.

Nige Wade

Dean,

I couldn't agree more,

I just want to protect my old friend from being vilified in the diving press.

 

Nige Wade

Vilified ... Mr Bantin ... Never!!!

Dive safe

DeanB

Subject: Likelihood of Damage to marine animals eyes by use of strobes.

 

I've written an article about this based on my own long experience photographing animals with up to 40,000joules of strobe. (A typical underwater strobe delivers a lot less than 100joules).

 

I also got the opinion from a distinguished professor in animal welfare - but he is my brother!

 

My editor would like to add the opinion of some independent marine biologist that has made a proper study (with a control group) of this. Do any of you know of such a study or such a marine biologist?

 

Thanks.

I don't think it is only retinal damage that needs to be thought about. There are publications (PNAS, 2007, p. 14712 by Whitmore's lab) that in zebra fish you can reset the whole circadian clock with light. There is another paper (Doc. Ophthalmol, 2006, p. 155 by Shinoda) that showed retinal damage in rats after photo flash exposure. We don't get the journal so I only see the abstract. On the other hand and probably most importantly fish unlike most mammals can very effectively regenerate retinal cells from the Muller glia (PNAS, 2008, p 19508, from TA Reh at Seattle). So while there may be some damage it shouldn't be permanent. Octopus can regenerate corneal cells but I don't find anything about retinal cells.

Bill

Well, I guess it's not as bad as those video lights.

Well seeing how predatory fish stay in the lights to hunt invert prey, I'd say video lights are actually not all that damaging. It's less powerful and once on, mobile fish can swim away. Once a fish is swimming the other way, it's pretty much certain they want to "avoid the light!" It's up to the person to either persist or desist.

After strobing it a dozen times, I was horrified to see a H.Pontohi just fall from its perch. I caught it in my open palm and my guide helped it back to where it came from. I was worried I'd killed it and stayed to watch it out of curiosity for ten minutes. It wasn't dead and eventually started moving about, but I decided there and then that I wouldn't do that again. When I told the resort's dive manager he replied "Don't worry Will, they're like ants" (!!!) H. bargibanti sometimes 'quiver' after a flash. I limit my shots and turn down the power with these little guys. On the other hand some critters seem to love it - squid, trumpetfish and barracuda come to mind.

It's been mentioned quite a few times and I've seen this a few times myself. One does have to ask if this is a defensive reaction vs systemic shock, which some fish have been noted to go into when strong light is used on them. John's quest is to figure whether it's permanent. If an animal goes into systemic shock, is it more vulnerable to predation? I'd guess yes. Now being eaten is also a permanent state, I'd imagine!

I don't think it is only retinal damage that needs to be thought about. There are publications (PNAS, 2007, p. 14712 by Whitmore's lab) that in zebra fish you can reset the whole circadian clock with light. There is another paper (Doc. Ophthalmol, 2006, p. 155 by Shinoda) that showed retinal damage in rats after photo flash exposure. We don't get the journal so I only see the abstract. On the other hand and probably most importantly fish unlike most mammals can very effectively regenerate retinal cells from the Muller glia (PNAS, 2008, p 19508, from TA Reh at Seattle). So while there may be some damage it shouldn't be permanent. Octopus can regenerate corneal cells but I don't find anything about retinal cells.

Thanks for those articles Bill. Fun read esp their methodology on Zebrafish, surgically crushing the retinas to see if they recover. Shimoda's retinal damage on rats was mostly in the UVA range. However, UV spectrum is visible to some fish, as they can even alter their epithelial mucus which absorb broad spectrum UV:

http://www.springerlink.com/content/m413883276x3u3n2/

What's more interesting is that this UV sensitivity decreases in some species of fish as fish enter different stages of development, as well as adjusted to hit certain prey species' UV blindspots and vice versa:

http://www.americanscientist.org/issues/fe...-up-marine-fish

http://www.britannica.com/bps/additionalco...-Up-Marine-Fish

Aww crap, now I've started UV photography underwater!

Once again I have to thank Wetpixel as a great resource. I've got the quote I wanted now. Thank you everyone.

(... and I don't think it's necessary for you to have your strobes confiscated by the animal cruelty police.)

Probably not. But, it may encourage them to take fewer-more thought out-photos instead of the spray and pray approach we see so often. I will, usually, take around three careful shots and then go to the end of the line before trying again. If there is an onslaught, I will stand on those few exposures.

Actually this sums up pretty well the approach that I think should be taken (and was suggested in the 'Underwater Photographer's Code of Conduct' which I was involved in producing some years ago). Banning something as un-policable as using flash photography on potentially sensitive subjects is unlikely to work, whilst educating underwater photographers to minimise the number of flashes is much more likely to be effective. The other point is that photographing a stressed animal is unlikely to produce a particularly good photograph anyway so should be discouraged on purely technical (as opposed to welfare) grounds in any case.

Actually this sums up pretty well the approach that I think should be taken (and was suggested in the 'Underwater Photographer's Code of Conduct' which I was involved in producing some years ago). Banning something as un-policable as using flash photography on potentially sensitive subjects is unlikely to work, whilst educating underwater photographers to minimise the number of flashes is much more likely to be effective. The other point is that photographing a stressed animal is unlikely to produce a particularly good photograph anyway so should be discouraged on purely technical (as opposed to welfare) grounds in any case.

Like a vast and extremely noisy potential predator getting up close won't stress an animal? The fox in my garden scarpers when I open the back door, long before I can get my flash/strobe ready!

Depends on the animal John. Some are very curious and can't help but come over to see what a diver is - I've had a basking shark deviate from its course and deliberately go over my head whilst I was in shallow water which was most likely because it was intrigued. And many small fish will disappear into holes then stick their heads out to find out what's out there. We always have an effect but not always a detrimental one and not all creatures are stressed by our approach. Your fox though has good reason to scarper based on previous human/fox interaction.

Been thinking a lot about this...(OUCH! My head hurts)

I would think the use of focus lights with strobe might LESSEN the possible retinal damage.

These critters do have irises. These irises would retract in the presence of steady light. That way, when the strobe fires, the light would be better filtered by the smaller iris opening.

What do you think?

Been thinking a lot about this...(OUCH! My head hurts)

 

I would think the use of focus lights with strobe might LESSEN the possible retinal damage.

 

These critters do have irises. These irises would retract in the presence of steady light. That way, when the strobe fires, the light would be better filtered by the smaller iris opening.

 

What do you think?

In my experience, many small fish (I've been working on gobies which often live in dark and murky conditions) are attracted to, or at least will stop and appear to be fascinated/intrigued by, a powerful focus light (I use a Kowalski mini xenon which is pretty potent) and will often pose for several flash - full power SB105 - shots before wandering off as though nothing has happened. I have seen nothing to indicate that they are in the slightest bit bothered by either the bright continuous light or the flashes. And they certainly can see to find their way around after being photographed. All this said, I along with a colleague, have been trying to show that gobies are easier to identify from good digital photographs than by the traditional method of capture and killing (a lot of marine science still resembles Victorian above water science in its methodology).

Once again I have to thank Wetpixel as a great resource. I've got the quote I wanted now. Thank you everyone.

(... and I don't think it's necessary for you to have your strobes confiscated by the animal cruelty police.)

What quote would that be? From the information I've been reading, there is no definitive answer. And unless there is direct studies done (perhaps by the Bantin Foundation) it won't be likely resolved any time soon. And that's just about the issue of strobe damage to the eyes of a fish. What of systemic shock and other side effects?

Like I said before, it'll be interesting to read the article if anything for the entertainment value.

The pygmy seahorse aside; most underwater critters do not appear to be the least bit perturbed by strobes. One would expect at least a startle reaction every time a strobe went off if they were suffering either stress or injury. I've never noticed underwater creatures to be startled by my strobe if they were not already stressed or startled by my presence. Our eyes too would likely be damaged by extended periods of high intensity strobe firing.