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Powerful Sonar Causes Deafness In Dolphins

Soulskill posted about 5 years ago | from the sorry-flipper dept.

Earth 323

Hugh Pickens writes "Mass strandings of dolphins and whales could be caused because the animals are rendered temporarily deaf by military sonar, experiments have shown. Tests on a captive dolphin have demonstrated that hearing can be lost for up to 40 minutes on exposure to sonar and may explain several strandings of dolphins and whales in the past decade. Most strandings are still thought to be natural events, but the tests strengthen fears that exercises by naval vessels equipped with sonar are responsible for at least some of them. For example, in the Bahamas in March, 2000, 16 Cuvier's beaked whales and Blainville's beaked whales and a spotted dolphin beached during a US navy exercise in which sonar was used intensively for 16 hours (PDF). 'The big question is what causes them to strand,' says Dr. Aran Mooney, of the University of Hawaii. 'What we are looking at are animals whose primary sense is hearing, like ours is seeing. Their ears are the most sensitive organ they have.' In the experiment, scientists fitted a harmless suction cup to the dolphin's head, with a sensor attached that monitored the animal's brainwaves, and when the pings reached 203 decibels and were repeated, the neurological data showed the mammal had become deaf, for its brain no longer responded to sound. 'We definitely showed that there are physiological and some behavioral effects [from repeated, loud sonar], but to extrapolate that into the wild, we don't really know,' said Mooney."

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323 comments

203 decibels? (4, Insightful)

TheLink (130905) | about 5 years ago | (#27505167)

Wow. I think if you expose me to a 203 decibel sonar, it's not just my ears that would go poof.

Re:203 decibels? (2, Interesting)

daem0n1x (748565) | about 5 years ago | (#27505819)

Can sound get THAT loud? According to this [wikipedia.org] , 115dB is the threshold of pain for humans. 203 dB is simply 33,000 times louder.

If you account for the high sound sensitivity of dolphins and water being a better sound conductor, just imagine the damage! It's like dropping a bomb on your head.

Couldn't the sonar be replaced by something less damaging? I guess water muffles radio waves, so a water radar is not a good idea. Maybe a very low frequency radar?

Re:203 decibels? (4, Insightful)

Shakrai (717556) | about 5 years ago | (#27505977)

Couldn't the sonar be replaced by something less damaging? I guess water muffles radio waves, so a water radar is not a good idea. Maybe a very low frequency radar?

The problem with that theory is that you'd need such a low frequency that your wavelength would be hundreds to thousands of miles. The antenna requirements alone would make such a system impractical on a mobile basis. Some of the antennas used for ELF submarine communications systems were up to 20 miles long.

Unless you can change the laws of physics I'm afraid we'll be stuck using sonar for the foreseeable feature. If you accept that then you have to accept the fact that the Navy needs to practice with it before they need it in an actual shooting war. Sucks that it apparently harms marine life but what can you do?

Re:203 decibels? (5, Insightful)

Macthorpe (960048) | about 5 years ago | (#27506035)

Sucks that it apparently harms marine life but what can you do?

Stop human beings from killing each other over nothing, obviating the need for submarines and therefore sonar?

I like to start small and work up.

Re:203 decibels? (4, Insightful)

Shakrai (717556) | about 5 years ago | (#27506133)

Stop human beings from killing each other over nothing, obviating the need for submarines and therefore sonar?

Good luck with that.

Re:203 decibels? (0)

Anonymous Coward | about 5 years ago | (#27506137)

I was just going to mention that 203dB *in water* has gotta be some bone shattering power. I mean there are those ultra-loud car stereos that you can't be within 30 ft of or they'll kill you and they're not even close to 203dB.

Also, isn't 203dB like 33000000000-ish times more powerful? I mean every 10dB is 10x power so the difference of 195dB and 115dB is 100000000, IIRC.

That sucks for them (5, Funny)

Em Emalb (452530) | about 5 years ago | (#27505183)

Guess dolphins and whales can't go to concerts. Although, I hear The Pingers have quite the underwater following.

In other news, when exposed to brilliant flashes of light, humans are rendered temporarily blind.

Re:That sucks for them (-1, Redundant)

Anonymous Coward | about 5 years ago | (#27505265)

I don't know about dolphins, but some girls I know would definitely constitute as whales.

Damd (0)

Anonymous Coward | about 5 years ago | (#27505185)

We'd better stay with laser sharks then!

Experiments like these... (5, Insightful)

fprintf (82740) | about 5 years ago | (#27505209)

Experiments like these are like putting people next to a jet engine to see if their hearing gets damaged. I am no PETA freak, but putting 200+ decibels is bound to do permanent damage. I know they said it is temporary, but that might be like my "temporary" hearing loss from the Boston show a few months back. Yes, I could hear fine afterward* but I wonder what incremental loss I might have had from all that loudness.

*I have higher pitch loss that apparently came from shooting a lot many years ago without hearing protection.

Re:Experiments like these... (2, Insightful)

esocid (946821) | about 5 years ago | (#27505301)

Your comparison isn't a good one. It would be like losing your vision for 40 minutes and wandering around with deep holes around for you to fall in. Once you're in those holes it's a fair chance you won't survive unless someone helps you out.
Anything that is used for prolonged periods (16 hours) is going to have detrimental effects on the mammals' methods of navigation. Why is it such a terrible crime that the Navy consider what damage it does to its surroundings? Not implying you, it's just their stance is TeRRorisM! our actions can't be hindered.

Re:Experiments like these... (3, Insightful)

Shakrai (717556) | about 5 years ago | (#27506083)

Why is it such a terrible crime that the Navy consider what damage it does to its surroundings?

What makes you think they don't already or that the damage to those surroundings is more important than our ability to keep the sea lanes open in the next shooting war?

Re:Experiments like these... (2, Insightful)

Anonymous Coward | about 5 years ago | (#27505319)

I am no PETA freak, but putting 200+ decibels is bound to do permanent damage.

Perhaps the experiment was inhumane. Hypocrisy demonstrated. Point taken.
That does not change the conclusion: military exercises that include sonar cause injury to advanced marine life.

The ramifications should be obvious, but just in case they aren't...

Harming endangered species is illegal, and for good reason...their extinction could have unwanted ecological consequences and will certainly have unwanted sociological consequences for us.
Harming non-endangered, but advanced, animals should be avoided when possible (for moral reasons and also the sociological consequences...nobody wants a PETA riot).

Re:Experiments like these... (-1, Troll)

Anonymous Coward | about 5 years ago | (#27505589)

Yeah, but have you tried arguing with an army? The Pentagon is a bunch of deadwood who uses your money to destroy this planet, and they'll be happy to use the guns you paid for on you.

Re:Experiments like these... (1)

Nutria (679911) | about 5 years ago | (#27505757)

nobody wants a PETA riot

Sure I do! That way DHS swoops in, rounds them up, and (based on all the left-wing whining and ravings you see in places like /. and dailykos) throws them in Gitmo with thousands, nay, billions of other domestic political prisoners and Belgians.

Re:Experiments like these... (-1, Flamebait)

geekboy642 (799087) | about 5 years ago | (#27506077)

You gotta catch up with the wingnuttery, dude. These days it's all right-wing whining about FEMA internment camps for Patriots, terror that the gubmint will take away their AK-47s, and the xenophobic "DEY TOOK OUR JAHBS!" ranting about immigrants.

The left sounds positively sane by comparison.

Re:Experiments like these... (1)

thedonger (1317951) | about 5 years ago | (#27506009)

...could have unwanted ecological consequences...

The building of Navy vessels most certainly has greater unintended/unwanted consequences than occasional deafening of advanced marine life. But either of those compared to a lack of preparedness on the part of our military to defend against threats foreign and domestic...Well, I guess it is all a matter of perspective.

Re:Experiments like these... (0, Troll)

aliquis (678370) | about 5 years ago | (#27505421)

Yeah, military, animal testers and consumers suck.

It's fucking obvious and they shouldn't develop techniques doing as much damage.

Re:Experiments like these... (0)

Anonymous Coward | about 5 years ago | (#27505433)

How about for the purposes of hunting? We can use sonar to round up whales, and who cares if they're deaf when we are going to kill them anyway?

Re:Experiments like these... (3, Insightful)

fugue (4373) | about 5 years ago | (#27505603)

Sort of like dropping a nuke on Denver in order to kill a few deer? Is it okay if I promise to eat everything I kill?

Re:Experiments like these... (2, Funny)

Shakrai (717556) | about 5 years ago | (#27506095)

Sort of like dropping a nuke on Denver in order to kill a few deer? Is it okay if I promise to eat everything I kill?

Well, if you go deer hunting with nukes you don't have to worry about cooking the meat afterwards ;)

And how does 203 dB compare to sonar levels? (0)

Anonymous Coward | about 5 years ago | (#27505537)

Gee, if the sonar levels the dolphins hear during the exercise is only, say, 180 dB then this was a dumb experiment, akin to testing whether someone could be hurt by a 1/2 oz plastic toy car to running around naked on the 405 at rush hour in LA.

Anyone know the sound levels sonar generates?

Re:Experiments like these... (5, Insightful)

radtea (464814) | about 5 years ago | (#27505597)

I am no PETA freak, but putting 200+ decibels is bound to do permanent damage.

The document linked on the Bahamas stranding says that source levels were 223 - 235 dB and levels were less than 180 dB at 300 m horizontally and 200 m vertically, so unless the dolphins were EXTREMELY close to the ships when the sonar was turned on the odds of even temporary deafness due to the use of sonar in the wild are quite low. Remember: a 40 dB difference in signal is a factor of 10,000 in amplitude of the pressure wave, so unless the dolphins were within a few meters of the source they would be very unlikely to get anything close to 200 dB.

This is a bit like dropping a 10 kg mass on a person and noticing it causes serious damage, and then arguing that you can say something about the effects of dropping 0.001 kg masses on people based on the 10 kg data.

That's not to say that it isn't plausible that dolphin sonar can be screwed up by powerful sonar, but this experiment just doesn't seem relevant to the question.

Re:Experiments like these... (5, Insightful)

INeededALogin (771371) | about 5 years ago | (#27505727)

The document linked on the Bahamas stranding says that source levels were 223 - 235 dB and levels were less than 180 dB at 300 m horizontally and 200 m

180 db is still extremely strong. Now, compound that with the fact that the Submarines are moving, pinging and that Dolphins are curious anmials and like to follow ships... and I think you will find that the chances for Dolphins being near one of these ships greatly increased.

Also, I understand the need to defend the human race, military and blowing stuff up, but ask any blind person how much noise pollution hurts and then comment again.

Re:Experiments like these... (4, Insightful)

Kamokazi (1080091) | about 5 years ago | (#27506135)

I think you're both essentially right.

If the dolphins were further away, the sonar would be far less damaging, but it could still interefere with their navigation.

It's also very possible that the dolphins were following the ships and exposed to deafening decibel ranges.

This study (like most studies) is just a stepping stone to narrow down criteria/goals for other studies...we need to A) Determine the effect of lesser decibel levels and B) Gather real observational data on how often dolphins and other marine life venture very near to naval vessels.

Ultimately results of these studies should just regulate situations on when active sonar is used, where you can train with it, etc, because active sonar is necessary until something better is developed. Despite the very slim chances of nuclear war, as tragic as it is, I'm willing to sacrifice a few hundred sea critters (I wold hope it's a much smaller number though) just to know that we can effectively track and destroy nuclear missile subs (as well as the many other uses for sonar). That's just my opinion and you can call me a barbarian for it if you like.

Re:Experiments like these... (0)

Anonymous Coward | about 5 years ago | (#27506223)

I don't need to be blind to want to kill the fucking assholes who think they have the right to have 5000W subwoofers to hear their "boom boom boom" noise all day long.

Re:Experiments like these... (5, Informative)

Anonymous Coward | about 5 years ago | (#27505869)

Unfortunately, neither you nor I can assess what "203 decibels" means. That is because that is a meaningless phrase. Here is the information that the AFP left out:

  • Where was the 203 dB measured? Was it measured at a reference range relative to the transducer, as is common practice, or was it measured at the dolphin? This [redorbit.com] implies to me that they produced a sound equivalent to 203 dB as heard at a 40 m range, but I am just guessing.

    The difference between the reference range measurement and the receiver measurement, assuming spherical spreading (which we're likely to see at a 40m range), is 20 log r, where R is the ratio of the reference range and the receiver range. If the dolphin is 100 m away from a source emitting 203 dB at a 1 yard reference range, it will be hit with acoustic energy at 163 dB (203 - 20 log 100).

  • In what units are they working? Contrary to popular belief, decibels are not a unit, but rather a scale. Saying the dolphins were exposed to 203 dB is equivalent to saying they were exposed to 2 x 10^8. 2 x 10^8 whats? Watts? Micropascals? 20 Micropascals?

    By the way, the sound pressure levels you're accustomed to reading about as an land-lubber are probably dB//20 uPa -- i.e., measured in multiples of 20 micropascals. In underwater acoustics we almost always use dB//1 uPa -- i.e., measured in multiples of 1 micropascal. To convert from the in-air numbers to under-water numbers, add 26 dB. A 203 dB sound to an underwater physicist would be a 179 dB to an atmospheric physicist.

Unfortunately I cannot find this article on the Biology Letters [royalsocie...ishing.org] web site to check the facts.

We can't stop or the terrorists will win! (1, Funny)

Anonymous Coward | about 5 years ago | (#27505239)

The US Navy absolutely must continue these vital SONAR experiments! This news is undermining our national security! These scientists are out of control. Are we sure this "dolphin" isn't a Qaeda sympathizer? Was it even vetted?

If we stop experimenting in high-power SONAR, the terrorists and their submarines win!

Re:We can't stop or the terrorists will win! (0)

Anonymous Coward | about 5 years ago | (#27505789)

I agree. It is better to slaughter every animal on the planet (except the ones we eat) to keep us a little safer. Who cares about the animals if we save even one American life! /end sarcasm/

F Dolphins (3, Funny)

scubamage (727538) | about 5 years ago | (#27505243)

Seriously, everyone knows that human wants and needs are more important than some stupid fish being able to hear. Its not like they need sound for anything.

Re:F Dolphins (1)

Em Emalb (452530) | about 5 years ago | (#27505425)

roflmcwaffle,
At first the parent post was modded troll, then funny, then troll then funny again.

I think you've broken slashdot.

Congratulations sir. Well played, well played indeed.

Re:F Dolphins (1)

y86 (111726) | about 5 years ago | (#27505555)

Seriously, everyone knows that human wants and needs are more important than some stupid fish being able to hear. Its not like they need sound for anything.

I actually sort of agree with this to an extent(human life/nation interests trump animal rights), however there has to be a better solution.

Shark use EM fields to detect life. Maybe we can strap sharks with sensor pods reading their brainstems.

After all, no one cares about sharks.

Retarded (1, Insightful)

Anonymous Coward | about 5 years ago | (#27505245)

I can't believe the military is still playing dumb and pretending they aren't aware their sonars are affecting marine life.

Must be nice to be in a permanent state of denial.

Re:Retarded (3, Insightful)

MightyMartian (840721) | about 5 years ago | (#27505453)

The reality is that they don't particularly care. They have to, for purposes of public relations, act like there's no problem, like what they're doing is perfectly fine, but the reality is that they could care less if every cetacean in the ocean died tomorrow.

Re:Retarded (3, Funny)

Anonymous Coward | about 5 years ago | (#27505463)

Must be nice to be in a permanent state of denial.

No it isn't.

Re:Retarded (1)

fugue (4373) | about 5 years ago | (#27505657)

Must be nice to be in a permanent state of denial.

It sure is! ...assuming that if someone tries to call you on it you happen to have a powerful army at your disposal...

you dont' need to make dolphins deaf. (3, Insightful)

DragonTHC (208439) | about 5 years ago | (#27505273)

You don't need to actually make dolphins deaf to know if they will be deaf! Not only is that cruel, it's unnecessary.

It's common knowledge that exposure to 200+ decibels will make anything deaf. And this Dr. Mooney is an idiot.

If it makes them deaf in a lab, it fucking works outside the lab!

Re:you dont' need to make dolphins deaf. (1)

causality (777677) | about 5 years ago | (#27505353)

It's common knowledge that exposure to 200+ decibels will make anything deaf.

It's common knowledge but now he's done a STUDY ("Oooooooh, Aaaaaaaah"). That means that what everybody already knew has somehow become more official!

I think this is a new plan.

1. Find some obvious thing that everyone already knows.
2. Get funding to have a "study" on it.
3. ???
4. Profit!

Re:you dont' need to make dolphins deaf. (3, Insightful)

je ne sais quoi (987177) | about 5 years ago | (#27505731)

Actually, it hasn't been proven that the Navy's use of sonar damages these organisms, if you read the dissenting opinion [sfgate.com] from the recent supreme court decision ruling in favor of the Navy versus environmentalists, they say as much:

Dissenting Justice Ruth Bader Ginsburg, joined by Justice David Souter, said Cooper had properly used her authority under the environmental law after finding that unrestricted sonar use could harm thousands of creatures. Instead of conducting an environmental study as the law required, or asking Congress to change the law, Ginsburg said, the Navy undermined the law with a "self-serving resort to an office in the White House" for an exemption.

This study represents a "nail in the coffin" type of study, where it is now known unequivocally that 203 decibels will harm wildlife. To logical people, this is what's known as "proof". Knowing this, you can now measure the sound level of the Navy's sonar tests and if it's above 203 decibels, you have direct evidence that the Navy IS harming marine animals. It sounds silly and trivial, but this is how logic works sometimes, you have to prove something beyond a shadow of a doubt, and past a shadow if you want to change society.

Re:you dont' need to make dolphins deaf. (1)

Em Emalb (452530) | about 5 years ago | (#27505363)

Hello, McFly! How the heck is he supposed to get more funding if he doesn't test his theories in the wild?

*sigh*

Re:you dont' need to make dolphins deaf. (1)

flaming error (1041742) | about 5 years ago | (#27505407)

> it's unnecessary.
I'd say ears are unnecessary to navies to about the same extent that eyes are unnecessary for armies.

Re:you dont' need to make dolphins deaf. (1, Troll)

Yvanhoe (564877) | about 5 years ago | (#27505451)

If that can help regulate the use of military sonars who seem to not care about mass-killing dolphins, I say it is worth it.

Re:you dont' need to make dolphins deaf. (1)

SpuriousLogic (1183411) | about 5 years ago | (#27505491)

I agree. This experiment is like stabbing someone with a big knife to see if they bleed. I am for sure no PETA freak - I love to hunt and 100% realize that killing animals causes them pain. But I ALREADY KNOW that shooting them with an arrow or bullet will kill them - I don't need an experiment to prove something I already know. The only thing I can think of that came out of this experiment was a dolphins threshold for hearing loss, but I have to think there are other ways to gain that knowledge.

Re:you dont' need to make dolphins deaf. (1)

JCSoRocks (1142053) | about 5 years ago | (#27505505)

I have to disagree with the validity of the statement that this carries over into the wild. Yeah, sure, if you have a dolphin tied to the side of your boat and you're sitting their blasting it with 203 decibels it'll go deaf. But do we know how quickly it drops off in strength or whether the dolphins would swim away before any lasting damage was done? Have they heard it in the past and learned to avoid naval vessels as a result? Couldn't they theoretically swim along the surface and avoid the sound altogether?

Re: Your Sig - Nazis of the world unite!

Re:you dont' need to make dolphins deaf. (1)

INeededALogin (771371) | about 5 years ago | (#27505805)

Couldn't they theoretically swim along the surface and avoid the sound altogether?

Have you ever seen a Dolphin? They aren't boats. The ability to keep their ears above water for an extended period of time would consume a lot of energy if they could even do it. Also, why is it that the dolphins have to change their million years of instincts and evolution so that we can search and destroy enemy ships. On that note, when was the last time we actually had to destroy a submarine?

Re:you dont' need to make dolphins deaf. (1)

geekboy642 (799087) | about 5 years ago | (#27506213)

You don't only care about the u-boats you want to destroy. You also care about the ones that pop up into the middle of a carrier group to say "Hi! Naval superiority? Yeah, you're OUR bitch now." [dailymail.co.uk] China has the superiority. It'd be real nice if we could take it back, seeing as how likely a shooting war on that side of the world is.

Re:you dont' need to make dolphins deaf. (1)

aliquis (678370) | about 5 years ago | (#27505527)

But was the results statisticly significant? Better test on a bunch of more dolphins to make sure!

Re:you dont' need to make dolphins deaf. (4, Funny)

robthebloke (1308483) | about 5 years ago | (#27505557)

It's common knowledge that exposure to 200+ decibels will make anything deaf.

Apart from deaf people.

Re:you dont' need to make dolphins deaf. (0)

Anonymous Coward | about 5 years ago | (#27505637)

It's common knowledge that exposure to 200+ decibels will make anything deaf.

Not true; rocks are not deafened by 200+ dB sounds.

Re:you dont' need to make dolphins deaf. (2, Interesting)

apokruphos (911590) | about 5 years ago | (#27505743)

Please, cite to me the journal of "Common Knowledge". Because, as we all know, all those folksy truths always have a huge bearing on reality.

Disarmament (-1, Troll)

Anonymous Coward | about 5 years ago | (#27505279)

I'm sure the neo-cons that have infested /. in the last couple years will disagree, but this is an excellent reason to start decommissioning "first strike" weapons like nuclear submarines, ASAP. We should be ashamed of ourselves, we are grotesque monsters killing sea life just so we can trade nukes faster.

Re:Disarmament (5, Interesting)

initdeep (1073290) | about 5 years ago | (#27505579)

you do realize that 99%+ of the time, these terrible nuclear submarines don't even use ANY form of sonar other than underwater microphones don't you?
To a similar (though not as high degree) neither do surface ships.

I didnt think so.

yet another example of a slashtard talking out of their ass with absolutely NO idea what they are talking about.

And yes, I did happen to serve on one of these terrible nuclear submarines.

and in the case of missle subs, it's probably closer to three nines or more.

ssbn subs are holes in the water that strive to make absolutely no noise.

you can hear the original sound wave a lot further off than you can hear the return echo which is always weaker.

and that's before you even throw in the effect of temperature gradients and convergence zones.

another thing to ponder is what was the frequency used?
and does this matter.

the reason i say this is that MOST sonar is low frequency or extremely low frequency, with the exception being high frequency sonar used to search for underwater mines and to penetrate ice fields.

of course, why mention these type things as they will just muddy the waters and potentially invalidate the test.........

(I said potentially, not that they do, i have no idea and based on the report, neither does anyone else)

Re:Disarmament (-1, Troll)

Anonymous Coward | about 5 years ago | (#27505625)

people use sonar trying to FIND subs, moron. If the subs aren't there, no sonar.

God, no wonder you went into the military. no other options.

Re:Disarmament (2, Informative)

tarius8105 (683929) | about 5 years ago | (#27505979)

people use sonar trying to FIND subs, moron. If the subs aren't there, no sonar.

God, no wonder you went into the military. no other options.

You are the moron. Subs dont use active sonar unless there is no other choice because it reveals their location. Subs use passive sonar 98% of the time. Calling him a moron and having no choice is an assumption based on that you are the moron. Any member on a submarine is not your normal enlisted seaman, they actually have to screen candidates so they can get the job done. Its not some infantry man throwing on some headphones and listening. Also if submarines used active sonar, we would never have news about two subs colliding as they could easily see each other.

Re:Disarmament (1, Insightful)

Anonymous Coward | about 5 years ago | (#27505851)

Random unstructured Tourette's-style musings rarely translate well in a written medium (even on Slashdot).

There's no doubt something valuable in your post, but unless you write out your thoughts in a coherent form, we won't know what it is.

Re:Disarmament (1)

peragrin (659227) | about 5 years ago | (#27505695)

You do know that subs very rarely use active sonar? It is giving away your position. Surface ships tend to use active sonar to assit in finding subs that are trying to hide. First strike weapons hide. That is their first goal. If you use active sonar you tell everyone within a couple hundred miles of exactly whereyour hiding.

Then again your an AC you probably don't know such basic things.

Re:Disarmament (0)

Anonymous Coward | about 5 years ago | (#27506141)

I'm sure the neo-cons that have infested /. in the last couple years will disagree

This isn't your own little private sandbox.

BTW SLBMs aren't really intended as first strike weapons although they could be used that way. They're meant to be counterstrike weapons because they're hidden away and cannot be reliably taken out in a first strike.

This probably causes permanent damage. (4, Interesting)

TerranFury (726743) | about 5 years ago | (#27505289)

Loud noises tear the cilia in your cochlea out by the roots. In humans, and, as far as I know, other higher mammals, they don't grow back (Can someone who knows confirm that this is true in dolphins as well?).

So the word "temporary" might make this sound less bad than it is: Our sonar may only temporarily cause total deafness, but I suspect it permanently degrades hearing.

Sucks to be a dolphin. Reminds me of Douglas Adams' sympathy for whales, whose songs no longer can be heard across the ocean. (I think Douglas talked about this in Last Chance to See.)

Re:This probably causes permanent damage. (1)

pembo13 (770295) | about 5 years ago | (#27505365)

Even if it is temporary, isn't this the equivalent of temporary blindness while on the highway?

Re:This probably causes permanent damage. (1)

drinkypoo (153816) | about 5 years ago | (#27505553)

These methods are definitely cruel. On the other hand, if the research actually led to a reduction in the power of sonar systems used, then it would be worth harming a few dolphins. The problem is that if anything the research will be used to figure out the minimum sonar power required to paralyse dolphins for capture so they can be trained as mine sweepers or something.

Re:This probably causes permanent damage. (1)

Chrontius (654879) | about 5 years ago | (#27506231)

Sorry, no - that's like asking what the minimum amount of light to stun a person is because you want a tac-light to use as a primary weapon. It doesn't work like that -- the answer to my question is "bright enough to ionize a thin layer of skin/clothing into an EMP-emitting plasma" and I suspect the answer to your question is "Loud enough to pulverize bone and tear nerve fibers". Problem is, both kinda cause permanent injury. Phasers don't have a magical stun setting, and you can't cause complete temporary incapacitation without at leastrisking permanent damage, making yield (captured healthy dolphins that can be trained up into useful minesweepers) low and unit cost prohibitively high, making swarms of drones the cheap and easy option.

Only military? (1)

ravster (1358439) | about 5 years ago | (#27505317)

So why only military sonar? Couldn't this happen even with regular sonar? Or is the military using more sound than is necessary?

Or is the Times just military-bashing?

Re:Only military? (1)

Walpurgiss (723989) | about 5 years ago | (#27505461)

My thinking is that most civilian craft employ only passive sonar, whereas military is much more likely to use both passive and active sonar. Active pings being what causes the damage.

Or maybe all craft have both active and passive capability, but the civvy crafts are less likely to need active for anything, and certainly military craft are more likely to test their active sonar more often.

Re:Only military? (1)

Guysmiley777 (880063) | about 5 years ago | (#27505629)

The most common type of sonar found on "civvy" craft would be a depth finder. Which would be a low power active sonar device. There's very little use in passive sonar (or high power active sonar) on civilian vessels outside of oceanographic research.

Re:Only military? (2, Informative)

EdipisReks (770738) | about 5 years ago | (#27505489)

So why only military sonar? Couldn't this happen even with regular sonar?

not a lot of high powered sonar use in the civilian world, i would guess.

Re:Only military? (2, Insightful)

initdeep (1073290) | about 5 years ago | (#27505651)

what do you think?

the military probably uses less sonar in day to day operations than the rest of the scientific community does.

after all, how can you plot out that wreck without side scanning sonar?
how can you map those undersea ridges and trenches without using some sort of down firing sonar?

the truth of the matter is, sonar as used by the military is mostly a passive system.

it's kinda like sitting out in the woods while hunting. you don't go around making a lot of noise because it can be heard further away than you can hear the animals you're hunting.

which, depending on the animal, either allows them to flee undetected or allows them to hone in on your location and find you and kill you.

it's the same reason military jets don't just fly around with their search radar on, because it can be detected a long way off, and with some simple geometry and two reception points, they know where the jet now is.....

and then they can use a less detectable method to eliminate that jet.

like say an infra-red heat seeking missle instead of one that requires radar guidance.

Temporary damage and singing under water... (4, Informative)

yogibaer (757010) | about 5 years ago | (#27505399)

"The deafness, though, was only temporary and the dolphin was not hurt in the experiment, said Mooney." So the experiment is still cruel but obviously no permanent damage. Deafness aside: Loud noise causes disorientation and nausea in humans, so why not in dolphins. BTW: A "singing" Whale produces a sound pressure level of up to 185 dB under water! (s. http://en.wikipedia.org/wiki/Sound_pressure_level#Examples_of_sound_pressure_and_sound_pressure_levels [wikipedia.org] ) So 200 sounds extreme but remember its not air we are talking about, but water. For comparison the hearing threshhold of a diver is 67dB at 1khz. The auditory threshhold through the air at 1khz is 0 dB.

Re:Temporary damage and singing under water... (0)

Anonymous Coward | about 5 years ago | (#27505843)

Sound waves, or sonar waves, or 2.4Ghz 802.11x waves, or light waves, will all have more trouble traveling through (insert any material here) than through air. As a simple test, try putting your wireless access point on the opposite side of a few inches or feet of concrete and look at what happens to your SNR (dB). 203dB at the source may be significantly less dB by the time it reaches whatever living creature under the water. The Parent raises a good point about hearing thresholds under the water, it seems significantly more dB is needed for any creature to "hear" anything while submerged. Can the scientists tell if the animals are really losing their hearing or if they are being jammed by the sonar frequency and they simply require quite a bit of time to re-attenuate after the jamming has ceased?

Re:Temporary damage and singing under water... (1, Informative)

Anonymous Coward | about 5 years ago | (#27505937)

Sounds travels better in water than in air. It's both faster and less attenuating in water. It's a strange thing, but sounds travels faster in denser media while RF travels slower in denser media. Spreading loss is the same, of course.

Humans rule! Dolphins can suck it! (1, Funny)

Anonymous Coward | about 5 years ago | (#27505509)

http://www.youtube.com/watch?v=CvoCojrj4qw

Sonar, Neocons, /. and such (-1, Troll)

Anonymous Coward | about 5 years ago | (#27505565)

1st someone said the Neocons have invaded /., wow I had a good laugh there and although this poster may think its the Neos its really those of you who have shaken off 8 years of moronic propaganda in regards to Global Warming, War on Terror etc. Its not that its all perfectly justified but what its not is not what the conspiratorialists who use the word Bush every other sentence have presented.

SONAR is useless in military applications and why it continues to be used is baffling.

http://en.wikipedia.org/wiki/Sonar [wikipedia.org]
"Active sonar is used when the platform commander determines that it is more important to determine the position of a possible threat submarine than it is to conceal his own position. "

203 decibels!? (0, Troll)

Spazmania (174582) | about 5 years ago | (#27505571)

You make a 203 decibel noise next to *anything* and it'll become deaf, including human beings. A vacuum cleaner is only 80 dB and the front rows of a rock concert only 110 dB.

Re:203 decibels!? (0)

Anonymous Coward | about 5 years ago | (#27505827)

Yeah well I doubt that same vacuum cleaner is 80 dB underwater my friend. Think about it. How do sound waves work.

Re:203 decibels!? (1)

sogoodsofarsowhat (662830) | about 5 years ago | (#27506225)

Actually this will kill a human being and anything else...if you are next to it...but here is the problem what is the distance from source for the 203db measurement! If its 1" then its not as big a deal. If its at 3 meters that a big deal. If its at 30 meters thats incredible. But since all we have is an spl measurement all we know it could be at 0.1mm which would make it not nearly as loud at 3 meters. Not complete data so completely useless.

to the "wellduh" taggers (5, Insightful)

dAzED1 (33635) | about 5 years ago | (#27505573)

My wife is a wildlife conservation researcher, and specifically works with animals in the Delphinidae family (which include dolphins). There's a lot of stuff she, and others, have to - must - verify, even if it seems to be a "wellduh."

The alternative would be that science just thinks correlation = causation. Is that what we want? "Well, Navy ships used sonar, and these whales stranded themselves...must be related. Case closed." Instead, someone did actual science showing that sonar causes real deafness in these animals. And someone wants to harsh that?

I say instead that there should be a tag, "abouttimetheyverified"

Re:to the "wellduh" taggers (1)

tnk1 (899206) | about 5 years ago | (#27506099)

Science is only useful to some people when it aligns with their sensibilities. That goes for pretty much all sides of whatever debate you are in.

In this case, the point is that they would rather not risk any dolphin be hurt to get a scientific answer. That's actually a fair position, as it is the one we take with humans.

That said, the Navy isn't just testing SONAR for shits and giggles, and you can be certain that the Chinese and Russians don't give a shit about dolphins. That means that it's necessary for science to step in to tell us just how far we can go before we start doing things to wildlife that are not outweighed by the national security risks.

"Common sense" is not going to be sufficient in this case, nor should it be.

Dolphin stranding in ancient Greece (3, Insightful)

ericferris (1087061) | about 5 years ago | (#27505623)

Classic Greek authors tell us that in the ancient Greece, dolphins and whales were already found stranded on the shore. This was a windfall for the locals, who were not eating meat very often. They saw it as a divine gift and thanked Poseidon for it.

So considering that the Greek galleys didn't use sonar, we need to stop barking at the wrong tree and find the cause of this phenomenon. My money is on a parasitic disease that affects the brain [caltech.edu] .

Re:Dolphin stranding in ancient Greece (2, Funny)

A Friendly Troll (1017492) | about 5 years ago | (#27505931)

Classic Greek authors tell us that in the ancient Greece, dolphins and whales were already found stranded on the shore. This was a windfall for the locals, who were not eating meat very often. They saw it as a divine gift and thanked Poseidon for it. So considering that the Greek galleys didn't use sonar, we need to stop barking at the wrong tree and find the cause of this phenomenon.

Unless, of course, there was a sonar-equipped sub from Atlantis somewhere nearby... Or submerged alien vessels.

Re:Dolphin stranding in ancient Greece (0)

Anonymous Coward | about 5 years ago | (#27506049)

Dang, you tin-foil hat folks beat me to it!

Re:Dolphin stranding in ancient Greece (1)

ericferris (1087061) | about 5 years ago | (#27506189)

Yeah, well, that's the kind of assumptions you need to make if you want to keep blaming the sonar of the *EVIL MILITARY* (thunder rolls).

The arrogance of every young generations is to believe all problems on Earth are created by their parents' incompetence. Get a haircut and a bath, you hippies!

Re:Dolphin stranding in ancient Greece (4, Insightful)

raddan (519638) | about 5 years ago | (#27506063)

Or maybe the causes of stranding are a many-to-one relation, i.e., that there is more than one cause, and that use of sonar is only one of them. E.g., you find dead birds with broken necks all the time. It is disingenuous to say that windows are the cause of all broken bird necks, and we can point out that people have found dead birds with broken necks even in antiquity. But it is equally disingenuous to say that windows have nothing to do with it.

Not all decibels are the same! (5, Informative)

Reverberant (303566) | about 5 years ago | (#27505673)

WRT to all of the "203 decibels, OMG!" comments: water decibels aren't the same as SPL decibels.

A decibel is the logarithmic relationship between one quantity and a reference quantity. For sound pressure level, we use the RMS pressure of the sound wave compared to a reference pressure that represents the threshold of human hearing (20 microPa): 20*Log10(P/20e-6)

Other types of decibels use different reference quantities. For example, vibration velocity in the USA uses a reference quantify of 10^-6 in/sec. Sound intensity (sound power through a unit area) uses a reference quantity of 10^-12 W/m2. So comparing sad sound intensity decibels to vibration velocity decibels is meaningless without normalizing the units.

In the case of water decibels, we use pressure as we do for SPL in air, but the reference quantity is different: for water, the reference quantity is typically 1 microPa. Therefore the 203 dB in water is approximately equivalent to about 170 dB SPL in air. Of course you still can't directly compare water dB to SPL because the wavelengths of sound in water are so much longer than wavelengths of sound in air.

In any event, 203 dB in water is very loud (and obviously harmful to aquatic life as demonstrated in the articles), but not necessarily in the same way that 173 dB SPL is loud/harmful to us.

Worst Case Scenario (0)

Anonymous Coward | about 5 years ago | (#27506087)

Why do they beach?

Well, in the worst case, I guess it could be that they'd rather be stuck on a beach than continue to endure the sonar.

Good thing (1)

SnarfQuest (469614) | about 5 years ago | (#27506111)

It's a good thing this affects dolphins instead of sharks. What platform would we use for our lasers if sharks were this easy to mess up?

Shallow Water (1)

ThatsNotPudding (1045640) | about 5 years ago | (#27506187)

Maybe shallow water very near the beach is less affected by sonar. Perhaps that's why a lot of these critters don't seem too interested in being chucked back into the noise by helpful humans.
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