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Powerful Sonar Causes Deafness In Dolphins
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."
Wow. I think if you expose me to a 203 decibel sonar, it's not just my ears that would go poof.
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.
Sent from your iPad.
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.
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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!
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 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.
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!
They're using their grammar skills there.
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.)
Or is the Times just military-bashing?
Maybe they beached just to get away from the awful noise?
"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) 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.
http://www.youtube.com/watch?v=CvoCojrj4qw
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"
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)
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.
Fantasy: http://ferrisfantasy.blogspot.com/
Now we have a new weapon for the inevitable dolphin uprising.
Saying your "phone ran out of batteries" is like saying your "car ran out of gas tanks".
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.
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.
i thought once I was found, but it was only a dream.
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.
. . . I don't think it's the decibels, but the frequency. Obviously military sonar frequency is the "Brown Note" http://en.wikipedia.org/wiki/Brown_note for dolphins and whales.
The sound is not just making them deaf, it's scaring the poor critters shit-less.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
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.
Oh, yeah, slashdot is a conservative hotspot!
Brett
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?
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
what we really need is dolphins. delicious dolphins.
The stories and info posted here are artistic works of fiction and falsehood.
Only fools would take it as fact.
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.
...now when they come for us, we'll be ready.
You feel sleepy. Close your eyes. The opinions stated above are yours. You cannot imagine why you ever felt otherwise.
Submarines are sneaky little bitches. 200+ dB sonar is painting a glowing "Shoot me!" sign on your hull for enemy torpedoes to follow. The "Shoot me!" effect goes (much) further than the effective range of your sonar, meaning that turning on active sonar is giving away a large advantage, and essentially a panic button. It is a thing to be avoided, so unless in times of war, active sonar is rarely used.
It seems that the Navy may be pursuing the wrong solution to increasing sonar range and resolution. Rather than increasing the transmit power to such levels, perhaps more sensitive receivers are needed. Whales and dolphins echo location capabilities exceed the current capabilities of Navy equipment and they don't need any 200db or more power outputs.
It is believed that whales can communicate over hundreds of miles. Such levels of sensitivity also lend themselves to passive detection (for the Navy) which is a far better strategy than banging away, letting the enemy know you are looking and where you are.
Have gnu, will travel.
And thus began Aquaman's cruel campaign of dominance over the feeble human race. Only decades later, put to work as slaves at the endless seaweed farms, did the puny nautical scientists determine that deafening dolphins was probably not a smart idea.
How do sound waves work.
It's a pressure wave in a physical media. Travels about 300m/s in air, 1500m/s in seawater. Damps out slower in dense media than sparse media, so it travels much further in water and retains its amplitude for longer.
When I played Phil Collins' Another Day In Paradise through a 1000-watt underwater speaker during an acoustics experiment near the Hudson Canyon a decade and a half ago, it was still readily audible to the hydrophone arrays towed by the other ships miles away.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Is up to his sneaky antics again.
really, it makes a tree deaf? how about ants? whales?
You do know that whales emit a sound that approaches 200 dB, right?
The Kruger Dunning explains most post on
To the best of my knowledge, SONAR is short bursts of loud noise broken by longer periods of quiet to receive and process the return echos. Two minutes of continuous sound is not going to happen. Even if the effect is cumulative, a cetacean would have to travel with the source for over five minutes which it is unlikely to do if the SONAR is injurious. Would you hang out in an excruciatingly loud environment?
Now, some will point to this:Sound can become trapped if a layer of warm water lies over cold water. When sound created in the warm zone reaches the cold water it can bounce back instead of travelling though it. This, Dr Mooney said, would have the effect of trapping the sound in the warm layer, where it would bounce around "like a ping-pong ball", giving whales and dolphins little chance of escaping it.
But, the thing is, dolphins and whales are mammals. The would leave the noisy layer when they surfaced. Therefore, they would quickly learn how to escape the sound: surface or dive.
The conclusions seem specious to me.
There is no "-1 offended" or "-1 you don't agree with me" mod options for a reason.
I, for one, am glad that the military is working on weapons to defend ourselves from the upcoming dolphin invasion. I know (from various sources) that the dolphinkind have been planning their move for dominance for a long time, but their efforts have been thwarted yet again by that intelligence and heroism of the US navy.
Go Humanity!
Well if you're really so pressed for time...
According to the very first result, a sonar source of 240dB will result in a perceived intensity of 180dB at a distance of 1km, and 150-160dB at a distance of 160km. However, this does not mean that the experiment was "dumb", and your attempt to dismiss what was in fact an entirely rigorous scientific experiment solely on the basis of your own failure to read the damned summary (let alone TFA) is more than a little grating.
In actual fact, prior research (albeit conducted "in the wild" rather than in the strict laboratory conditions that this recent article was) has shown that whales and dolphins will actively avoid, and even show obvious physical distress at sonar at intensities as "low" (relatively speaking - in fact it's actually not very low at all) as 120dB. Yes, that does mean that marine life over 100 miles away from the actual source of the sonar will be suffering negative effects.
Going back to this recent experiment, however, and your oh so obligatory /. car analogy, allow me to correct the analogy to something more suitable. This experiment was like testing whether someone would be hurt by having a car run into you at 50 mph, and discovering that, yep, that's gonna hurt. Then they gradually ramped up the speed, and brought in bigger cars, until they discovered that when you get hit by an SUV going at 90 mph, you're going to be dead before you hit the ground. That's what the 203dB figure represents. They increased the intensity of the sonar pings until they discovered the point at which the dolphin became totally deaf. The experiment was totally methodical and rigorous, and about as far from "dumb" as you can possibly get.
Santa's suicide mission go!
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.
...
Probably much of what people claim as 'recovered' hearing is probably just getting used to the hearing loss.
I'm not sure how they spin the "temporary" aspect of the dolphin's hearing loss. Do the spinmeisters mean that some hearing is lost, temporarily when measured in the grand scheme of things? Or that on an absolute scale that although the hearing loss lasts for the rest of the dolphins' lives, that only amounts to just a few days and thus the hearing loss is 'just temporary'.
Beta is broken and the link to classic doesn't work. Stop wasting our time or there won't be anybody left here.
Why doesn't anyone tag this as "failwhale"? Is it because of the technicality that dolphins aren't whales? Still, it's such a good opportunity!
I was in the navy and trained extensively in ASW operations. They don't use active sonar that is sonar that emits sound much if at all because it gives away your position like putting a giant bullseye on your sub or ship.
They generally use towed array passive sonar which is an array of sensitive acoustic listening devices towed well behind the sub to be separated from the cavitation of the prop. And it does not emit sound. So this whole oh noes the evil Military is buttfucking sweet mother Gaia sounds like BS in this case.
They do dump a lot of trash in the ocean though as I understand it they are incinerating much of that now.
If they'd played that loud on land at me I'd jump to the ocean. qed.
1 Earth is warming, 2 It's us, 3 it's royally bad, 4 we need to take action NOW
This is terrible! These poor dolphins. Stupid researchers should just leave them alone!
I wonder if dolphins have alien abduction experiences? The aural equivalent of a blinding light, a sensation of disorientation, shadowy figures inserting implants into their brains, powerful military technology and tacit government involvement... The truth is out there.
This is about the oldest news I've seen on /.
Sonar isn't nearly as loud as a torpedo or depth charge exploding under water.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Honestly I kind of miss the taste of the 50/50 tuna to dolphin blend in starkist tuna cans. Gave it a little bit of a zing.
Maybe since the water is the medium for the sound that is causing them pain, they are trying to leave that medium to stop the pain. I don't know, but makes sense to me.
You'll never understand because you'll never undertake the effort. Try taking a good look around the very page you're on; you'll find several explanations as to why this isn't really as bad as what you're thinking in your knee-jerk response.
Actually no, don't. Go ahead and keep whatever worldview you have that makes you think all them there scientists are just beatin' up dolphins all day.
This would be a very interesting study if they had of tested how the effect of military sonar on dolphin and whale hearing can cause beaching. All they did was show that yes dolphins are affected by sonar. Something that could pretty much be inferred from biology and physics. We don't need to shoot dolphins to prove they are vulnerable to bullets.
The problem with this study is that a follow up to show a how much military sonar effects beachings probably won't happen for years, if it ever happens. And in the mean time we will have PETA and the like demanding that sonar not be used because of the "scientific proof" that it causes most beachings, or something equally stupid.
I wonder when they will find out what high power radar used to do to birds? Of course Dolphins are higher up the cute scaleâ of animal compassion.
========
CINC, 4th Penguin Legion
Assuming your ping comes from the sub, of course, and not something that the sub dropped five minutes ago...
I am TheRaven on Soylent News
"...scientists fitted a harmless suction cup to the dolphin's head..." Okay, harmless is good... "... when the pings reached 203 decibels and were repeated, the neurological data showed the mammal had become deaf..." Hmm... not so harmless. 203db would to some pretty significant and permanent damage to human ears and ours aren't even as sensitive as dolphins'. How is this surprising?
"Far more sensitive hearing" depends on the frequency range. If you look at the curves on this page you can see that while dolphins are indeed far more sensitive to (aquatic) sounds in the higher frequencies than humans are, their low-frequency thresholds are pretty high.
dude, jokefail.
I'd personally kill every Dolphin myself if it would save a human life.
Ah, if you kill every dolphin, you'll also be killing humans. Though rare, dolphins have saved humans, especially from sharks.
Falcon
Should there be a Law?
http://www.underwatertimes.com/news.php?article_id=48723961015
That study used fish. Fish are not mammals but dolphins, porpoises, and whales are.
Not that I personally believe it don't effect them, though we may not know how to tell.
Marine mammals are shown to hemorrhage from sonar.
Falcon
Should there be a Law?
When I played Phil Collins' Another Day In Paradise through a 1000-watt underwater speaker during an acoustics experiment near the Hudson Canyon a decade and a half ago, it was still readily audible to the hydrophone arrays towed by the other ships miles away.
Jonesy, is that you? That can be heard all the way down to Pearl Harbor.
Falcon
Should there be a Law?
"Their ears are the most sensitive organ they have"
"The big question is what causes them to strand"
Here's an idea: if you overload their "most sensitive organ" to a point of leaving it numb for 40 minutes, that is pretty much torture.
Imagine that happening to you: a loud noise powerful enough to leave you deaf.
The answer: you run!
In the beaches, where they are stranded, these noises probably are not perceived (their ears are out of the water).
I'd rather die than continue listening to you!
It's not panicky if you want 1 ping only ;)
Maybe since the water is the medium for the sound that is causing them pain, they are trying to leave that medium to stop the pain. I don't know, but makes sense to me.
Yes, and maybe it's simply a rudimentary (leftover) instinct. AFAIK their ancestors were land-dwellers before entering the oceans. In the transition period it would have been essential for survival to evade some unbearable pain (or generally a situation they can't parse) by returning to land.
As they got more and more used to living in the oceans, the situations where this instinct was triggered became less frequent. And when they finally became unable to return to land, the (now fatal) escape-to-land alerts had become so rare that they didn't hurt the population as a whole, so the instinct never fully went away.
Say out loud: I'm an Aspie and I'm somewhat proud, I guess. Uh. Can I write an email in all caps instead? Hm...
You'd think the Navy would pay attention to this. I can't imagine that leaving a trail of oddly-behaving animals would be good for keeping their boat's whereabouts under wraps. "Your sub was in my harbor!" "No, it wasn't" "The trail of deaf and confused dolphins suggests otherwise!"
You are not the customer.