Mid-frequency sonar signals linked to new pathologic entity in cetaceans.
An ongoing battle has been fought between environmental NGOs , mainly NRDC , and the US Navy for more than a decade.
The first rumours re the harmful impact of LFA ( Low –frequency Active) sonar on marine mammals, began already in 1994 , when NRDC investigated sound experiments off California coast. Even 300 miles from the source , these sonic waves have an intensity of 140 decibels , and some mid –frequency sonar systems can put over 235 decibels , as loud as a Saturn V rocket at launch.
The use of deadly sonar in the world’s oceans is spreading. The US Navy states ,the sonar is needed to detect hostile diesel –electric submarines from China, Iran and North Korea and other potential hostile countries.
In late January 2008, a dead Northern Right Whale Dolphin washed ashore off California , and this death was linked to ongoing naval exercises.
Sonar possible cause in death of rare dolphin
“ The lesions that we have seen to date are consistent to what has been found in the Canary Islands and the Bahamas”, said lead veterinarian , Rowles , with the National Oceanic and Athmospheric Administration.
“Scientists in the journal Nature theorized that these deep-diving whales might have panicked and bolted to the surface, causing decompression sickness, similar to the “bends” or air embolisms that can affect human divers. The problem arises when gas bubbles, compressed under the pressure of depth, expand rapidly and tear delicate tissues”
Excerpt from Nature : “ Macroscopically, whales had severe , diffuse congestions and hemorrhage , especially around the acoustic jaw fat , ears , brain , and kidneys . “
Severely injured whales stranded and died due to cardiovascular collapse.
Another useful link :
LA Times: Dolphin dies near sonar site
Cheers,
Ann Novek
Sweden
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Save the whales. Let humans die.
Even 300 miles from the source , these sonic waves have an intensity of 140 decibels
Somebody needs to review their power laws with respect to energy.
I’d bet more marine mammals have been harmed by NRDC boats than by the acoustic imaging experiments.
Rob, with global warming and manmade pollution of the oceans, sonar energy does not dissipate like it used to, over distance. Something about the warmer, dirtier saltwater that keeps energies high. Even reflected and refracted sonar does not lose energy–it gets stronger!
“…sonar energy does not dissipate like it used to…”
LoL. You mean the historical record going back in time using coral ring cores and adjusted for offshore urbanization reveals an alarming “hockey stick” shaped acoustic energy curve?
The usual mix of anecdotal evidence, loose associations, coincidence and outright speculation. Cardiovascular failure from sound waves? Give us a break. And tell that to Keith Richards.
Anyway David never did get back about that translation of that Japanese paper saying it was all a massively subsidised money losing operation to produce a stockpile of uneaten whale flesh.
” Cardiovascular failure from sound waves? Give us a break. ” – Motty
If Motty had bothered to read through the link that I provided to Veterinary Pathology , then he should have been able to see that the whales surfaced to quickly , causing compressed gas bubbles to burst inside them and damage internal organs and tissue ( also known as decompression sicknes in divers).
That in turn would cause hemorrhage and death.
To be continued….
Part II:
Injured whales have a tendency to beach themselves as well . In this case they had bubble-associated tissue injuries.
The heart can stop pumping blood ( a condition known as cardiovasvular collapse , that happens when there is a rapid loss of blood pressure , and the tissues and organs do not get enough fluids and oxygen).
The loss of blood pressure in this case was due to hemorrhage ( loss of blood from the circulatory system)
That may well be the case, Ann, but the actual cause of the sudden rise to the surface (at a rate much faster than normal) is pure speculation, is it not?
It is one thing to establish that the loss of blood pressure was caused by rapid ascending but another altogether to establish what, amongst a number of possibilities, may have caused them to rise so rapidly.
Libby – Motty is on the pace after all.
http://www.news.com.au/couriermail/story/0,23739,23340214-952,00.html
Japan breeds cows with whales – wow !
And not many publications either it seems.
Luke? Feeling OK?
Hi Luke,
The Frankenwhale research has been mentioned before, but it’s interesting how “great minds” think alike. There’s another mooovie for you – it’s alive! (Cue lightening strikes and a deranged wild-eyed assistant rubbing his hands together).
Hi Ann,
There’s heaps of literature about LFA and cetacean events.
http://www.eurocbc.org/ecbc_ci_lfas_effects_on_marine_mammalspage1230.html
(Just from a quick lazy google).
Yes I’m fine David but still concerned about those Japanese newspaper reports.
Luke: “Anyway David never did get back about that translation of that Japanese paper saying it was all a massively subsidised money losing operation to produce a stockpile of uneaten whale flesh.”
I`m not sure of the paper you refer to, but I don`t think it`s a revelation that the research whaling fleet is now owned by the government, run at a loss and that Japan`s whale stockpile has doubled in the past decade.
And what does Japan and its citizen`s gain from this folly? It forestalls actually addressing pressing ocean commons issues and is a black eye, but maybe it satisfies someone`s self-righteous nationalism.
But probably a bit less counterproductive and expensive that the US unending war on our pocketbooks.
Ann, Libby and Luke can try all the diversionary spin they like but we all know that whales would respond in a very similar way to cattle after a suitable sequence of basic pavlovian signals rewarded by food. And no amount of cosmic voodoo would alter the key conclusion that these animals have similar intellect to cattle.
Who knows, maybe the key to sustainable harvesting is to use satellite technology to identify large schools of Krill, then drop acoustic transmitters into that food source that send a familiar pattern of audible signals to every Minke within 100km. And once they are there make sure the whales make the link between the signal and the fleet.
It would be man and animals combining to improve their access to food supplies at less cost in whale energy stocks to locate those supplies. The health and survival rates of the whale herd would improve in the same symbiotic relationship as that between bovine and human.
And they would also be nicely concentrated where they can be sexed and tagged economically for future location and harvesting.
Sleep well tonight folks. All it will take is for the whaling nations to rid themselves of the IWC straight jacket. And that seems to be proceeding exactly according to plan.
Yee ha ! Right over the edge.
Norway conducts world unique research on sonar on killer whales in northern fjord , Vestfjord.
Researchers from around the world are gathered here to get information on the impact of military sonar on whales.
Research permits are here easier to get than in the US. Whalers !!!! work together with scientists here to tag the whales with D-tags , that endure only a few hours.
The research is conducted by the Norwegian Defence Research Establishment.
About 3 nautical miles from the killer whales the sonar will put on. Diving patterns and sounds from the whales will be registered.
As I have understood the research can only be conducted inside of the fjord.
See pics:
http://www.mil.no/felles/ffi/start/article.jhtml?articleID=131259
The background for the 4-year Norwegian research on the impact of military sonar on whales and strandings , is because new fregates will be be running with equipment that operate on as low frequences as 1-2KHZ and with an output of 220dB.
Thanks libby for the links!
Link in Norwegian:
http://www.imr.no/aktuelt/nyhetsarkiv/2003/november/effekt_av_lavfrekvent_sonar_pa_dyreliv_i_havet
“Scientists in the journal Nature theorized that these deep-diving whales might have panicked and bolted to the surface, causing decompression sickness, similar to the “bends” or air embolisms that can affect human divers. The problem arises when gas bubbles, compressed under the pressure of depth, expand rapidly and tear delicate tissues”
This is crap. Marine mammals don’t suffer from bends.
Does anyone know why?
Thanks for your comment TokyoTom.
>but we all know…
One sign of delusion is referring to imaginary others. Of course what he actually posts is another clear sign. The tiny voice from the last whaling thread realises no none is listening to him but insists everyone knows he is right, despite evidence to the contrary. Why this individual insists he is always right and wants to disrupt the flow of interesting and useful information remains a mystery, but it is disappointing and boring.
As I think you know Ann, there were some strandings of oceanic whales and dolphins linked to naval exercises off Tasmania a few years ago. I think it was discussed here previously.
“This is crap. Marine mammals don’t suffer from bends.
Does anyone know why?”
Thanks Paul,
I was amazed that nobody else caught this. Must not be any scuba divers here. A whale is a free diver, it breathes air at sea level pressure, not compressed gas. 🙂 -Dave
Thanks, Paul and Dave. Another green myth that is well and truly busted. I was going to ask, given that whales normally dive fairly deep anyway, (how else would they get that deep) and rise in circular fashion releasing bubbles to encircle a school of Krill, why these supposedly intelligent animals would suddenly change their behaviour to their detriment. But you have trumped that very nicely.
So where does that leave us? Well, no evidence that sonar has prompted the sudden rise. And no apparent scientific basis for the claimed outcome.
Seekers of truth = 2
Bull$hit artists = 0
As Aldous Huxley said, “to believe some things one must be an intellectual, ordinary men would never be so silly”.
So who, exactly were these “scientists” in the Journal Nature, who have been exposed for completely talking through their backside?
That’s right Dave, and outside water pressure shuts down the alvoeli, or air sacs, in the lungs, so that no Nitrogen is absorbed from the lungs for the vast majority of the dive.
And of course, the US Navy is not the only one to use sonar, even if it is implicated in some way to whale deaths.
Thanks Paul and Dave for your interesting analysis. Heres’ an article from Experimental Biology:
” Sound-and-orientation recording tags (DTAGs) were used to study 10 beaked whales of two poorly known species, Ziphius cavirostris (Zc) and Mesoplodon densirostris (Md). Acoustic behaviour in the deep foraging dives performed by both species (Zc: 28 dives by seven individuals; Md: 16 dives by three individuals) shows that they hunt by echolocation in deep water between 222 and 1885 m, attempting to capture about 30 prey/dive. This food source is so deep that the average foraging dives were deeper (Zc: 1070 m; Md: 835 m) and longer (Zc: 58 min; Md: 47 min) than reported for any other air-breathing species. A series of shallower dives, containing no indications of foraging, followed most deep foraging dives. The average interval between deep foraging dives was 63 min for Zc and 92 min for Md. This long an interval may be required for beaked whales to recover from an oxygen debt accrued in the deep foraging dives, which last about twice the estimated aerobic dive limit. Recent reports of gas emboli in beaked whales stranded during naval sonar exercises have led to the hypothesis that their deep-diving may make them especially vulnerable to decompression. Using current models of breath-hold diving, we infer that their natural diving behaviour is inconsistent with known problems of acute nitrogen supersaturation and embolism. If the assumptions of these models are correct for beaked whales, then possible decompression problems are more likely to result from an abnormal behavioural response to sonar”
” And of course, the US Navy is not the only one to use sonar, even if it is implicated in some way to whale deaths.” – Paul
NATO is using LFA sonar and who knows what the Chinese and the Russians etc are using in their Navy , where we have even less insight?
Anyway , sound pollution is an extremly important issue ….
Anne, that’s the authors opinion. Do they supply any information on what the likely “abnormal behavioural response to sonar” actually is?
Beaked whales ascend slowly from deep dives, but there is nothing to suggest that this is a protective response to prevent gas bubbles forming, as it is only for the last bit of the ascent, when sea pressure is low enough to permit the alveoli to open that Nitrogen exchange can occur. And the dive profile is no shallower during this than any other part of the ascent.
As Ian says, why would an animal develop a “panic” response that actually causes its death?
Good point, Paul. And given that the use of sonar is more than 50 years old, and used by all navies on earth and numerous fishing fleets and individual power boats, why would a continuous and repetetive sequence of sonar blips be a surprise to any marine species?
And one must ask, by what strange set of circumstances would a sonar get turned on when one of these rare beaked whales just happens to be at great depth?
And even if this was the case, and there was no earlier sonar signal as they descended, why would they go all the way to the surface? Surely their first response would be to be surprised but as the signals continued they are more likely to conclude that it is another bunch of those noisy humans.
But what I find more concerning in this story is the way it was first portrayed as some sort of universal threat to whale-kind but subsequent inquiry reveals it to be based on observation of a few instances of a rare species.
It is the same old, same old, with extrapolation to extreme from specific, anecdotal evidence.
It is far more likely, if a rapid ascent is the real cause of the condition, that these deep diving species have had the bejesus scared out of them by a hot pursuit from a giant squid, a natural predator at those depths.
But who could ignore the classic, “Using current models of breath-hold diving, we infer that their natural diving behaviour is inconsistent with known problems of acute nitrogen supersaturation and embolism. If the assumptions of these models are correct for beaked whales, then possible decompression problems are more likely to result from an abnormal behavioural response to sonar”
Come again? They admit that the natural diving behaviour of these whales is inconsistent with their MODELS of nitrogen supersaturation and embolism. But then rely on these obviously unrealistic assumptions to conclude that “possible decompression problems” are more likely (more likely than what?) to result from an abnormal behavioural response (after 60 years of exposure) to sonar.
This statement has a veneer of scientific plausibility to it but in reality it is pure, unfounded speculation, the unambiguous mispronunciation of the bowels. It is fluent “Bull$hitistani”.
Motty, I agree completely. But boy, the voodoo dolls will be taking a hiding tonight. And watch out Paul and Dave, keep track of your hair now.
Paul and Dave,
I haven’t got the Nature article in front of me (or the time to go looking for it), but I have a paper from last year entitled “Responses of cetaceans to anthropogenic threats.”
The paper tables observed responses of some species to anthropogenic noise, including abrupt dives, avoidance, reduced vocalizations, longer time between breathes. It is not uncommon now to have marine mammal observers on ships such as seismic vessels, but there are obvious issues involved with reporting marine mammal reactions to naval activities.
In reviewing military sonars and stranding events the authors write that beaked whales are the major group that have been involved in these events, although other species have also been involved. They review an atypical stranding event of Cuvier’s beaked whales (a species I have observed at sea). “Over 2 days, 12 Cuvier’s beaked whales stranded over a 38km stretch of coastline in Greece with an average separation distance of 3.5km. This mass stranding was atypical as animals involved in such events usually occur close together in time and space (ie. they involve one group of whales coming ashore together in the same location). The original author of the incident (Frantzis) associated these with military testing of an acoustic sonar system for submarine detection. Of course reading the full original article will provide you with more info.
“Jepson et al (2003, 2005) and Fernandez et al (2004, 2005) conducted necropsies of beaked whales from strandings that coincided with naval sonar exercises, and they reported the presence of gas or fat emboli, which they interpreted as consistent with a decompression-like syndrome. There has been scientific disagreement about these findings, which differ from reports of decompression in humans (Piantadosi and Thalmann, 2004). Reports of emboli stimulated additional interest in the Crum and Mao (1996) report that exposure of supersaturated tissue to intense sound in vitro could cause or enhance bubble growth.”
“It has also been suggested that the proximate cause of death in these strandings may simply be the physical and thermal trauma of stranding itself. However, Fernandez et al. (2005) reported that decomposed beaked whales washed up on beaches in the Canary Islands several days after an offshore naval exercise, suggesting that actual stranding was a prerequisite for lethal injuries. Furthermore, some of the pathologies described in live-stranded whales (Ferandez et al, 2004, 2005) were not consistent with effects of stranding alone. Jepson et al (2003) suggested that exposure to sonar might trigger a behavioural reaction at reaction levels below those required for physical injury, and that the behavioural reaction may cause decompression-like symptoms in addition to causing strandings. After reviewing all hypotheses proposed to date, Cox et al (2006; p 177) concluded that ‘gas bubble disease, induced in supersaturated tissue by a behavioural response to acoustic exposure, is a plausible patholgic mechanism for the morbidity and mortality seen in cetaceans associated with sonar exposure.’ ”
Rossiter writes:
“the extensive analysis of the sonars and environemnt that were implicated in the 2000 Bahamas stranding could only conclude that the combined sonars of several ships had been “ducted” by specific water conditions.”
Beaked whales occur in very deep waters and most species are rarely seen in-situ. In fact new species are still being discovered. Many tend to be nervous animals from what I have read and observed. Their lives consist of dives to great depth and in many areas, with very little contact with vessels. The theory is that a sudden loud noise, consisting of pulses or beats, could likely startle these animals, thus causing a change in behaviour. Modern sonar, under certain environmental conditions, could quite easily be something these animals are not habituated to. Cetaceans are acoustic animals, it is their primary means of communication and in some species navigation. Any unusual sound, particularly loud, would realistically cause some form of behavioural change, small or large.
There is as well another theory , called the resonance ( shaking) theory out among the researchers, re the cetaceans injuries from supposed sonar impact. ( I will post in two parts as I have computer problems).
“”The beaked whales found in the Canary Islands are not the only stranded cetaceans to provide evidence of bubble-associated tissue injury,” the authors wrote. They discovered similar injuries among dolphins and harbor porpoises found dead off England in the last decade.
Whale researcher Ken Balcomb finds the explanation compelling, even though it conflicts with his theory that powerful sonic waves in the water literally shake and tear delicate air-filled tissues in ears and brains, causing bleeding, disorientation and death.
Experts in physics are skeptical of his “resonance effect” hypothesis, questioning whether these sounds could result in sufficient reverberation of tissues to cause them to tear apart.
“Yet everyone agrees that once you have bubble formation, it would be a runaway situation,” Balcomb said. “You cannot stop it, just like you cannot put bubbles back into the champagne bottle.”
Balcomb, senior scientist at the Center for Whale Research in Friday Harbor, Wash., spent a decade studying beaked whales in the Bahamas, where U.S. naval ships using powerful sonar swept through the area in March 2000, leaving 16 dead and injured whales in their wake”
Part II:
“An extensive study by the National Marine Fisheries Service attributed the mass die-off to high-intensity sonar, concluding that it caused bleeding around the inner ears and trauma to the brain and auditory system. Yet it remained unclear whether the whales were fatally injured by the sounds or whether they were simply so disoriented that they drowned or died of stress and overheating after beaching themselves.
Necropsies of the beaked whales in the Canary Islands found similar hemorrhaging in the ears and brain, said Antonio Fernandez, professor of pathology at the University of Las Palmas on Grand Canary Island and one of 18 Spanish and British coauthors of the Nature article.”
Part III:
” Fernandez said researchers also found that expanding nitrogen bubbles had damaged kidneys, livers, lungs and other organs, suggesting “that naval sonar could induce a condition similar to decompression sickness.” More research was needed, he said.
Beaked whales and some types of deep-diving dolphins have been the most common casualties associated with deployment of military sonar. The most recent case came in May, when 16 dolphins, mostly Dall porpoises, were found dead after a U.S. warship cruised along the U.S.-Canadian border north of Puget Sound.
Beaked whales are known to feed at depths of 3,300 feet. When they surface for air, they descend immediately to 90 feet for 12-minute intervals, Balcomb said. He likened this to the “safety stop” practiced by human divers to allow nitrogen to escape safely from the bloodstream.
Panic could disrupt this practice, he said. “This is a plausible theory, as is the resonance [shaking] theory. They could be working together here. Either way, we are seeing this consistent pattern of dead animals after military sonar is being used all over the world.”
The harmul effects of sonar don’t only have an impact on cetaceans and seals , but it’s believed they have an equal or worse harmful effect on fish stocks and spawning grounds.
In Norway , there has recently been imposed restrictions on the use of sonar in herring fields and especially in herring spawning grounds. It seems like herring is especially vulnerable to sonar.
The Norwegian defence authorities are working together with Woods Hole Oceanograhic Institution USA.
http://www.forskning.no/Artikler/2006/mars/1143028711.24
Libby and Anne, as far as I know, (and I’m not a whale expert by any means!), there’s little or no evidence to suggest Nitrogen supersaturation occurs in beaked whales.
That’s because Nitrogen is in the lungs only for the first 80 – 100 metres of the dive. After that, increased pressure closes the air sacs in the lungs, and the air that was in the lungs at the surface is now vastly compressed and occupying the space in the upper airway, where the mucous membrane is too thick to allow gas diffusion into the tissue.
Similarly, the theory that the “shallow” dives after a deep dive are to allow Nitrogen to escape safely from the bloodstream doesn’t make sense, because these dives extend below the depth at which the lungs contain gas.
These recovery dives are likely to be to allow the whale to recover from the effects of prolonged anaerobic metabolism incurred during the deep dive, while staying away from predators in the top layer of the ocean.
Paul,
I have some papers in front of me : ” Elements of beaked whale anatomy and diving physiology and some hypothetical causes of sonar -related strandings. Trying to do a summary from this in a few days.
Excerpt from the paper: ” It has been hypothesised that bronchial sphincters regulate airflow to and from the alveoli ( air sacks) during a dive. Under compression , the alveoli in the cetacean lung collapse and gaS FROM THEM CAN BE FORCED INTO THE REINFORCED UPPER AIRWAYS OF THE BRONCHIAL TREE.
Thus, nitrogen is isolated from the site of gas exchange , reducing its uptake into tissues and mitigating against potentially detrimental excess nitrogen absorption.
The microanatomy of beaked whales has not been described and its therefore an area requiring future research.”
” Are you comparing beaked whale anatomy and diving physiology vs human dito?”
Posted by: Ann Novek at March 9, 2008 06:59 PM
Sorry Paul, I misinerpreted your post and have asked Biggsy to delete it!!!!
Can you please post some references?
Hi Ann,
“Thus, nitrogen is isolated from the site of gas exchange , reducing its uptake into tissues and mitigating against potentially detrimental excess nitrogen absorption.”
That’s what I was referring to in my last post.
As far as I can see from the paper you linked, the sonar/gas bubble hypothesis depends on some assumptions;
1. Sonar causes an “abnormal behavioural response”
2. This response is rapid surfacing
3. This causes bubble formation resulting from hypersaturation of the whales tissue with nitrogen
4. Bubble formation causes death, somehow.
Does this seem a reasonable summary do you think?
If so, do you know of any evidence to support these assumptions?
As I said, I’m not in any way a whale specialist, so I’m really just floating ideas. I’ll see if I can dig up some references. (I did a course recently, and some of these human/animal comparisons came up as lateral thinking exercises).
Thanks again Paul for your balanced comment and summary.
Another excerpt from my above link.
” Thus the occurance of unusual mass strandings of beaked whales is of particular importance. In contrast to some earlier reports , the most deleterious effect that sonar may have on beaked whalea may not be trauma to the auditory system as a direct result of ensonification.
Evidence now suggest that the most serious effect is the evolution of gas bubbles in tissues, driven by behaviourally altered dive profiles ( e.g extended surface intervals) or directly from ensonification.”
Finally , researchers are concerned why beaked whales mass strand , since beaked whales usually are solitary animals.
There seems to be no shortage of whale experts here but there is a serious dearth of sonar experts. Some of the comments in the references appear to imply that sonar is a sudden event that scares the willies out of beaked whales. It is my understanding that this is wrong.
Sonar is used continually by all but the smallest naval vessels. Every passage involves continuous operation of sonar as one of the primary surveillance tools. So the sounds would very rarely be able to surprise anything. They would first be detected at considerable distance and grow stronger over time as the ship came nearer.
The exception to this are the submarines who generally employ as close to complete silence as possible as their main non-aggressive role is to listen and observe rather than broadcast their presence with loud noises. And it should be noted that these practices are not something that is only done during exercises. Every operating moment is used to practice and maintain these essential skills.
If there was any sort of naval activity that was capable of inducing shock and panic reactions it would have to be from live firing, bombing and depth charging exercises. These explosives are specifically designed to punch large holes in a very big lump of steel. So if you think dynamiting fish is a big buzz, just wait till you see what 150kg of semtex will do.
And some of these practice events can take place with little warning and could certainly rattle the daggs of any fish life that happen to be in the area.
It seems obvious that some here have not been at sea and think it is a place that is comprehensively utilized at all times. Because a tool has been in use since last century does not mean that animals have become used to it, particularly when they do not encounter is regularly. A basic understanding of animal behaviour and conditioning will tell you this.
There is passive sonar and active sonar. Both have been developed extensively over time – in other words they are much more effective than they used to be. Not all types of sonar are in operation the entire time, as some of the references supplied above highlight, emphasising the point that the sound doesn’t ‘grow stronger over time.’ Mid and low frequency sonar are not used by all naval vessels.
http://www.whalesandsonar.navy.mil/sonar_history_and_use.htm
http://www.whalesandsonar.navy.mil/understanding_sonar.htm
But this is what it comes down to:-
‘The Navy is concerned about the potential effects of active sonar on marine mammals…The Navy will continue to fund research and use mitigation measures to minimize the potential effects of sonar on marine mammals, but cannot put the lives of its Sailors at risk or fail to remain prepared to defend our nation by eliminating active sonar use.’
Interesting to note that the low frequency active sonar with the range out to 160km is only at 10 kHz) is primarily used for determining water depth (fathometers), hunting mines, and guiding torpedoes. At higher frequencies, the sound energy is greatly attenuated (weakened due to scattering and absorption) as it travels through the water. This results in shorter ranges, typically less than five nautical miles.
Mid Frequency: Mid frequency sonar, which includes the AN/SQS-53 system, has been in use since World War II, and is the primary tool for identifying and prosecuting submarines. Mid frequency sonar (1 kHz – 10 kHz) suffers moderate attenuation and has typical ranges of 1-10 nautical miles. (19km)
Low Frequency: Low frequency sonar (< 1 kHz) produces sound that suffers less attenuation as it travels through the water, providing greater range than other sonars. Achieving ranges up to 100 nautical miles, (190km) low frequency sonars are primarily used for long-range search and surveillance of submarines. Surveillance Towed Array Sensor System Low Frequency Active (SURTASS LFA) is the U.S. Navy’s low-frequency sonar system.
And to place this into proper perspective,
“Species that live in the same habitat may have overlapping, but not necessarily identical, hearing ranges. For example, smaller odontocetes have a hearing range of up to 150 kHz, while mysticetes (including gray whales) have an estimated hearing range from 20 Hz to at least 3 kHz.”
So the long range sonar (<1kHz) operates well below the estimated hearing range of whales (3-20kHz). Furthermore, 30% of the mid-frequency sonar (1-10kHz) with range from 1 to 19km, also appears to operate below the range of whales. Indeed, this entire frequency class operates in the lower half of the range for whales and well below that of the smaller cetaceans.
And as the range of sonar is directly related to the frequency, we must conclude that the upper half of the mid-frequency sonar that does overlap with the range of whales also has the shortest range.
The reporting on this thread of 140 to 200 decibels of sonar at “300 miles” (500km) sounds impressive but if those decibels are well below the audible range of the whales then they are irrelevant.
The USN fact sheet at
http://www.whalesandsonar.navy.mil/documents/Sonar_Marine_Mammal_Fact_Sheet.pdf also points out that,
“Often overlooked causes of strandings include fishery entanglements, pollution, disease, parasite infestation, ship strikes, trauma, and starvation. Strandings also occur after unusual weather or oceanographic events.
A recently publicized report by the United Nations Environment Programme (UNEP) rated sonar last among current threats to dolphins, porpoises and related species. Sonar was reported to threaten only about 4 percent of these species, compared with 70 percent endangered by fishing and 56 percent by pollution. (http://www.unep.org, “Fishing Nets Major Risk for Small Cetaceans”).”
Just by way of reference to whales capacity to make and therefore hear sound, Wikipedia had this to say, http://en.wikipedia.org/wiki/Whale
“Whales also communicate with each other using lyrical sounds, called whale song. Being so large and powerful, these sounds are also extremely loud (depending on the species); sperm whales have only been heard making clicks, as all toothed whales (Odontoceti) use echolocation and can be heard for many miles. They have been known to generate about 20,000 acoustic watts of sound AT 163 DECIBELS.(my emphasis)”
So what, exactly, is Ann bunging on about? The low frequency long range sonar operates below their audible range and the decibel levels are quite similar to the levels they make themselves.
And they absorb these robust sound signals through their jawbone, not through some delicate human style membrane.
They absorb the echolocation signals they send out THEMSELVES through their lower jaw. Go have a read on the ‘all-knowledgeable’ Wikipedia and see if you can understand the physics of odontocete echolocation.
If you actually read the links provided, you would be better placed to comment ‘knowledgeably’. The link I provided was by the US Navy, so OBVIOUSLY one has to allow for that fact. What are the decibel levels for mid and low frequency sonar Ian? Is it the ability to ‘hear’ the sound, or the force of the sound if the animals are in the vicinity? Think about it. Startle responses have been mentioned already. Do we have good knowledge of what beaked whales hearing is? No.
No one is disputing there are other causes of strandings. That is obvious. Anthropogenic noise is emerging as a major problem for marine species, for the reasons outlined here alone. Ann’s post is educating us on one source of this problem.
Typical techy reply from Travis who doesn’t appear to have noticed that the quotes I gave were from the same source as his. Clearly, I took the time to read a lot more than he did. And one would expect that the US navy has a pretty good idea of the range of their sonar and its volume.
Ann’s post is misleading in that she quotes distance and decibel data that only apply to low frequency sonar but which are outside the audible range of all cetaceans.
There is a specific issue in respect of the smaller beaked whales that operate in a higher frequency band but at these frequencies the range, and therefore the threat, is limited.
And as has already been pointed out, the beaked whales operate at the very edge of the biophysical envelope and have modified their diving behaviour to deal with most of these circumstances. And it is an equally plausible explanation that some of the mortality could have been caused by entirely natural interference with their normal recovery behaviours. For example, if their normal shallower recovery dive was interrupted by a predator.
It should also be pointed out that the pain level in a human ear (130Db) is a lot less than what would apply to a hearing system based, not on a thin membrane in a gas, like ours but, rather, a jawbone in liquid, like theirs.
” Ann’s post is misleading in that she quotes distance and decibel data that only apply to low frequency sonar but which are outside the audible range of all cetaceans.” – Ian
I have a quote here from NRDS ” Protecting Whales from Dangerous Sonar” : ” …by the Navy’s own estimates , even 300 miles from the source these sonic waves can retain an intensity of 140dB – still a hundred times more intense than the noise aversion threshold for gray whales”.
” …the decibel scale for measuring sound is logarithmic, 235 decibels is billions of times stronger than the 120 decibel noise aversion threshold for gray whales — the level at which gray whales have been shown to be disturbed”
http://www.spiritual-endeavors.org/m-earth/navytest.htm
Yes Ian, I noticed you took the section from the link I provided, which is why I reiterated it came from the US Navy site. So in typical style you have accused me of doing something which isn’t true. The only time you took to read something was from that site, which I provided and had clearly read. You have not read anything else.
>And one would expect that the US navy has a pretty good idea of the range of their sonar and its volume.
I’m not doubting the navy has an idea. I am doubting that you have. You conveniently omitted the intensity of these sonar activities, which are crucial to the case being discussed here.
>Ann’s post is misleading in that she quotes distance and decibel data that only apply to low frequency sonar but which are outside the audible range of all cetaceans.
>There is a specific issue in respect of the smaller beaked whales that operate in a higher frequency band but at these frequencies the range, and therefore the threat, is limited.
Absolute crap Ian. If the threat is limited, the Navy would not have such PR, courts would not have rulings overriding presidential plans and there would not be the plethora of data out there from a range of experts that currently exists. You are clueless and deliberately obfuscating.
>And as has already been pointed out, the beaked whales operate at the very edge of the biophysical envelope and have modified their diving behaviour to deal with most of these circumstances. And it is an equally plausible explanation that some of the mortality could have been caused by entirely natural interference with their normal recovery behaviours. For example, if their normal shallower recovery dive was interrupted by a predator.
More crap and grasping at straws. Do you know what a beaked whale is Ian? One minute it is a giant squid that is the predator, now you are saying their predator is in shallower water. It has already been pointed out that these animals are adapted to a life of deep diving. In a world of modern humans there are now circumstances that beaked whales are not used to. What sort of a predator would it be? One they are not adapted to? Perhaps a cookie cutter shark snuck up on a group of beaked whales without them noticing and caused a rush to the surface, even after milenia of beng adapted to such things! Your argument makes no sense at all, and is constantly being adapted to suit.
>It should also be pointed out that the pain level in a human ear (130Db) is a lot less than what would apply to a hearing system based, not on a thin membrane in a gas, like ours but, rather, a jawbone in liquid, like theirs.
You are so stupid it defies belief! There is no use comparing human ears and pain threshholds to cetacean’s. Do cetaceans have EARS Ian? Hmm? Yes. Do you know what the lower mandible is used for? Hmm? NO! As I wrote, the lower jaw is a receiver for the echo that individual sends out. They do not use their lower jaws for hearing Ian! They have ears for that purpose!! Hence they have been found with BLEEDING EARS!!!
It would be funny if it weren’t for the fact that it is plain for all to see that you are deliberately being argumentative and making false baseless claims. What purpose does it serve, that’s what I want to know. It must be time for Alex to take a breath surely.
Just hold on here. In one post we are talking about 140Db being a hundred times greater than the “noise aversion threshold” for Grey whales and in the following post we are told that this threshold is actually 120Db?
And then we get “the decibel scale for measuring sound is logarithmic, 235 decibels is billions of times stronger than the 120 decibel noise aversion threshold for gray whales — the level at which gray whales have been shown to be disturbed”
Come again? “235Db is BILLIONS of times stronger than the 120Db”? So 140Db is hundreds of times higher than 120Db and 235Db is billions of times stronger? Have you guys suspended any association with mathematical reality?
Travis has apparently not retained the quote from wikipedia which stated that “(whales) have been known to generate about 20,000 acoustic watts of sound AT 163 DECIBELS”. Funny, how 140Db can be hundreds of times greater than the noise aversion threshold (comfort level) yet the same animals are pumping out much higher levels themselves.
Travis’ little number about selective hearing with their own signals (at 165Db) being picked up by the jawbone while those from human sources (at 165Db)go directly to the ear reads like a four cone conversation. Classic Super Whale Wally. Leaps from insult to mathematical absurdity in a single burst of zealotry.
Hey, hey Ian,
Don’t want to be picky here , but did you miss the physics lessons ???? ( I know as well that I make mistakes ,especially spelling errors) but it is dB for decibel , NOT Db!!! A decibel is one tenth of a bel (B).
Re your critic above , gonna make a new calculation , as I did not check the citations closely.
Here is some information on what odontocetes use their echolocation for and how:-
‘All toothed whales use clicks as the very basis of perception. It’s sonar, echolocation, the primary means by which they perceive their often-murky underwater world, just as humans rely primarily on eyes to perceive our world. A staccato burst of clicks bounces off an object such as a squid and echoes back to the whale where it is received through nerve receptors in the jaw. The animal “hears” this echo as an actual three-dimensional image possessed of a certain shape, material density and distance. Nonetheless, whale echolocation follows the same physical laws of acoustics that produces sonar in submarines and ultrasound imaging in pre-natal care.’
So echlocation is used to find prey and navigate. The animals possess the ability to control the intensity of the pulses they produce from the fatty melon. The echo returned via the lower jaw is of course not necessarily of the same intensity as the pulse sent out, accounting for scattering, absorption, and other means of attenuation.
It is believed that the same sound-producing set up for echolation is employed in prey debilitation, where loud ‘bangs’ are produced to stun or debilitate prey. ‘Acoustic evidence for prey debilitation is difficult to collect’, but in so producing these sounds, the animal would not be receiving an echo back, as it is not echolocating.
However, the prey stunning hypothesis is not largely supported:-
‘The hypothesis that sounds produced by odontocetes can debilitate fish was examined. The effects
of simulated odontocete pulsed signals on three species of fish commonly preyed on by odontocetes
were examined, exposing three individuals of each species as well as groups of four fish to a
high-frequency click of a bottlenose dolphin [peak frequency (PF) 120 kHz, 213-dB peak-to-peak
exposure level (EL)], a midfrequency click modeled after a killer whale’s signal (PF 55 kHz,
208-dB EL), and a low-frequency click (PF 18 kHz, 193-dB EL). Fish were held in a 50-cm
diameter net enclosure immediately in front of a transducer where their swimming behavior,
orientation, and balance were observed with two video cameras. Clicks were presented at constant
rates and in graded sweeps simulating a foraging dolphin’s “terminal buzz.” No measurable change
in behavior was observed in any of the fish for any signal type or pulse modulation rate, despite the
fact that clicks were at or near the maximum source levels recorded for odontocetes. Based on the
results, the hypothesis that acoustic signals of odontocetes alone can disorient or “stun” prey cannot
be supported.
Just out of amusement view:-
Some further information:-
‘So if whales don’t use sound waves to knock out squids, how do they catch them? “Why can’t [squids] see some aspects of this big whale heading down on them at a zillion miles an hour? That’s a big mystery,” Hanlon said.
One clue comes from observations of whale hunting in the wild made by study team members Peter Tyack and Peter Madsen, of the Woods Hole Oceanographic Institution and the University of Aarhus in Denmark, respectively.
The researchers recorded whales twisting their bodies just before snatching a squid in their jaws. “They often catch the prey in a rapid turn during which the whales turn upside down to position themselves with respect to the prey,” Tyack said.
This twisting maneuver seems to somehow allow the whales to create a powerful suction with their mouths, which they use to vacuum in squids from up to three feet away. Some squid are large enough to fight back: sperm whales have been found with suction scars on their skin. But most squid species make easy preys for the whales that hunt them.
While toothed whales don’t seem to use sounds to zap squid, some whale species are known to use sound to hunt fish. Humpback whales, for example, broadcast sound waves that drive herring fish into tight schools at the surface of the water for easier capture.
Other humpbacks simultaneously blow a “net” of bubbles that encircles the rising school. The whales then swim up the trap from beneath to scoop the clusters of frightened fish into their open mouths.’
Concerning actual hearing in cetaceans:-
http://books.google.com.au/books?id=E7xLaYVGEF4C&pg=PA19&lpg=PA19&dq=dolphin+whale+ears&source=web&ots=KHCSjt8Pr-&sig=E35KiHMRtAx8T1BH1SgW2UH4PxA&hl=en
It mentions that even though dolphins are adapted for relatively loud sounds in the ocean, they should not be continuously subjected to loud sounds similar to a boiler factory.
So cetaceans have ears, and they use them to hear the sounds of con- and co-specifics as well as environmental sounds.
Lesson over, until the dunce at the back of the class wants some more attention.
Ian,
I believe that the noise aversion threshold like the threshold of pain is dependent of frequency…
“Anatomy of the ear [From wikipedia]
See also: Evolution of cetaceans
While there are direct similarities between the ears of whales and humans, whales’ ears have specific adaptations to their underwater environment. In humans, the middle ear works as an impedance matcher between the outside air’s low-impedance and the cochlear fluid’s high-impedance. In aquatic mammals such as whales, however, there is no great difference between the outer and inner environments. Instead of sound passing through outer ear to middle ear, whales receive sound through their lower jaw, where it passes through a low-impedance, fat-filled cavity.[6][7]”
So will someone explain to our resident blog nutter that the function of the lower jaw is not limited to echo location but to the processing of all sounds.
And thank you, Travis, for providing more evidence of the intensity of sound that is produced by different species at different parts of the spectrum.
“effects of simulated odontocete pulsed signals on three species of fish commonly preyed on by odontocetes were examined, exposing three individuals of each species as well as groups of four fish to a high-frequency click of a bottlenose dolphin [peak frequency (PF) 120 kHz, 213-dB peak-to-peak exposure level (EL)], a midfrequency click modeled after a killer whale’s signal (PF 55 kHz, 208-dB EL), and a low-frequency click (PF 18 kHz, 193-dB EL).”
Lets just repeat those again, 213-dB, 208-dB and 193-dB, all of which, according to Ann, are “billions of times stronger than the 120 decibel noise aversion threshold for gray whales”. But these levels are routinely produced by a broad range of species and consequently, must also be routinely received by all species. And they have been doing so for millions of years.
Yes, Ann, we would really like to know why 140-dB from a sonar is more harmful than 213-dB from another whale?
According to my calculations:
– If the intensity is increased with 10dB , this means that the sound level increases 10 times
– If the intensity increases 20db , this means that the sound level increases 100 times
– If the intensity increases with 100 db, this means that the sound level increases 10 BILLION TIMES
I might be wrong , has anybody any better formula ?
Travis seriously want us to believe that Ian has been claiming whales have no ears. The way it read to me was that he was pointing out that there is no thin membrane like an eardrum that seperates the air from the inner liquid, (because this would obviously be torn under pressure). Your personal attacks are really getting tedious.
Ann, that is a really pertinent question. Why is 140-dB from a sonar more harmful than 213-dB from another whale?
According to http://www.engineeringtoolbox.com/decibel-d_341.html
“Increasing the sound intensity by a factor of
10 raises its level by 10 dB
100 raises its level by 20 dB
1,000 raises its level by 30 dB
10,000 raises its level by 40 dB and so on” So,
100,000 raises its level by 50 dB
1,000,000 raises its level by 60 dB
But this is on a scale from zero intensity.
“A reason for using the decibel is that the ear is capable of detecting a very large range of sound pressures. The ratio of the sound pressure that causes permanent damage from short exposure to the limit that (undamaged) ears can hear is above a million. Because the power in a sound wave is proportional to the square of the pressure, the ratio of the maximum power to the minimum power is above one (short scale) trillion. To deal with such a range, logarithmic units are useful: the log of a trillion is 12, so this ratio represents a difference of 120 dB. Since the human ear is not equally sensitive to all the frequencies of sound within the entire spectrum, noise levels at maximum human sensitivity — for example, the higher harmonics of middle A (between 2 and 4 kHz) — are factored more heavily into sound descriptions using a process called frequency weighting.”
And caution is needed when comparing aerial sound with sound in water.
Underwater hearing
http://en.wikipedia.org/wiki/Underwater_acoustics
“Comparison with airborne sound levels.
As with airborne sound, sound pressure level underwater is usually reported in units of decibels, but there are some important differences that make it difficult (and often inappropriate) to compare SPL in water with SPL in air. These differences include:[32]
difference in reference pressure: 1 μPa (one micropascal, or one millionth of a pascal) instead of 20 μPa.[14]
difference in interpretation: there are two schools of thought, one maintaining that pressures should be compared directly, and that the other that one should first convert to the intensity of an equivalent plane wave.
difference in hearing sensitivity: any comparison with (A-weighted) sound in air needs to take into account the differences in hearing sensitivity, either of a human diver or other animal.[33]
Hearing sensitivity
The lowest audible SPL for a human diver with normal hearing is about 67 dB re 1 μPa, with greatest sensitivity occurring at frequencies around 1 kHz [34]. Dolphins and other toothed whales are renowned for their acute hearing sensitivity, especially in the frequency range 5 to 50 kHz [35][33]. Several species have hearing thresholds between 30 and 50 dB re 1 μPa in this frequency range. For example the hearing threshold of the killer whale occurs at an RMS acoustic pressure of 0.02 mPa (and frequency 15 kHz), corresponding to an SPL threshold of 26 dB re 1 μPa.[36] By comparison the most sensitive fish is the soldier fish, whose threshold is 0.32 mPa (50 dB re 1 μPa) at 1.3 kHz, whereas the lobster has a hearing threshold of 1.3 Pa at 70 Hz (122 dB re 1 μPa).[36]
Safety thresholds
High levels of underwater sound create a potential hazard to marine and amphibious animals as well as to human divers [33]. Guidelines for exposure of human divers and marine mammals to underwater sound are reported by the SOLMAR project of the NATO Undersea Research Centre[37]. Human divers exposed to SPL above 154 dB re 1 μPa in the frequency range 0.6 to 2.5 kHz are reported to experience changes in their heart rate or breathing frequency.”
So there are a number of points to make from this.
The example of the killer whale which does not hear any sound under 26 dB but it must be at a frequency of at least 15kHz. The high decibel long range sonar is <1 kHz and even the medium range sonar is 1 kHz to 10 kHz, also well under the threshold.
Note how the lower threshold for humans in air is 1dB but rises to 67dB in water. The pain threshold of humans in air is 120dB but in water 154dB will only increase heart rate.
Note how lobsters don’t hear a thing until it gets to 122dB but this is at only 70Hz while the most sensitive fish hears nothing until it hits 50dB at 1.3kHz. So all the long range sonar is below the threshold for the most sensitive fish.
This consideration is absolutely essential in understanding the impact, or lack of impact, of sonar on marine species and it is a matter of record that this is rarely mentioned in the numerous green web sites that warn of the dangers posed by sonar. They are guilty of allowing the reader to assess threats posed in water by reference to levels applied in air.
Shame on you.
It’s just as well you clarified yourself there Mott.
Your reliance on Wiki is disturbing. If you are still doubting that low frequency sonar is a serious threat to marine mammals then you really are a nowhere man in your nowhere land (well, you’ve got your tape worm Alex for company). You seem to be obsessively debating what some here have written rather than the actual issue, which is not unusual.
-‘As the acoustic impedance is much the same in water as in cetacean bodies, there is no requirement for specific open canals linking the ears of cetaceans directly through their body tissue, but there do appear to be some preferred pathways through or wave-guides. In dolphins, these include a pathway through the lower jaw.’ (Emphasis mine)
-For mysticetes it is not known how they receive sounds. ‘They have occluded external auditory canals that are filled with wax and their lower jaws are designed for sieving or gulp-feeding.’
-‘Telescoping (of the skull and head) may have been driven essentially by non-auditory influences, but it also produced a multilayer skull that seriously impedes sound transmission through the head. Telescoping was accompanied by a dramatic repositioning of the ears.’
-‘At present, the bulk of experimental and anatomical studies indicate specialized fatty tissues in the jaw region are the primary route for conveying sound to odontocete middle and inner ears.’
-At this stage, all we know clearly about mysticete sound reception is that the great whales do not have an ear, skull, jaw, and soft tissue suite that is a larger-scale version of the odontocete head; therefore sound reception mechanism differ in the two suborders.’
-‘The position and isolation of odontocete bullae support the jaw bone theory of ultrasonic signal reception via fatty acoustic wave guides in and around the mandible. Sound reception mechanisms in mysticetes are unknown, but bony skull connections and a highly derived tympanic membrane suggest combined bone and soft tissue mechanisms. The extracranial location of the ear in all whales is advantageous for underwater sound localization.’
-From a 2006 paper ‘Like terrestrial mammals, cetaceans use their ears for hearing, but the functional components of cetacean ears are not well defined. Cetaceans lack an external ear, and the functionality of cetaceans’ “middle ear” is debated.’
-‘The channels through which sound traves from the outside world to the inner ear in cetaceans are bewildering, and those used by baleen whales are entirely different from those used by toothed whales.’
-‘Behavioural studies of bottlenose dolphins indicate that sound propagate to the inner ear differentially depending on both the direction from which the sound arrives, and the frequency content of the sound.’
-‘Many of the anatomical differences between mysticete and odontocete heads and skulls are undoubtedly related to differences in their habitats and foraging strategies, but they may also reflect their relative dependence on low versus high frequency signals, respectively, because skull properties will affect how different frequencies propagate into a cetacecans’ head. Odontocetes, in particular, are believed to receive high frequency sounds through specialised bones and fat channels associated with their lower jawbones, but to receive lower frequency sounds through bone-free fat channels just below their eyes, and posterior to their lower jaw bones.’ There is an associated figure showing this to encompass the dolphin’s “outer ears.”
In summary, we are both right going by what is currently known of cetacean hearing abilities and following yuor clarification.
Alex, your personal attacks as Mott and existence as a sock puppet is getting tedious.
That begrudging effort is probably as close as Travis will ever get to a display of good grace/breeding/class. His mum might let him get away with it but I’m not his mother. His boorishness in the above posts are ample demonstration of the way he allows his animosity towards me to completely cloud his perceptions to the point where he starts to imagine excuses for highly defamatory attacks.
Meanwhile back at the thread, we still await Ann’s explanation of how and why a 140-dB signal from a sonar is more harmful than a 213-dB signal from another whale?
This is especially interesting when the 140-dB signal from the sonar is low frequency <1kHz (below their audible range) and the 213-dB signal from another whale is medium to high frequency 15kHz+, right in the middle of their audible range, and delivered close up by another member of their pod.
What? Not a word from Libby? or Wu? Or any of the other defaming whale wallies on this blog?
Once again, the green zealots have done their cause a disservice due to their almost pathological need to to go right over the top with silly exaggeration and clutching any lurid factoid to support their position.
I bet the beaked whales that do have a problem with sonar would be really impressed with their self appointed spokesmen and saviours. I mean, tilting at windmills is sssooooh passe when you have a whole planet to save, don’t you think?
Travis seems to think I am your imaginary friend, Motty. Thats odd because some might think he was actually Libby’s imaginary friend. It’s all getting a bit weird. Next he will be wearing an armadillo shell hat to ward off the CIA mind probes. I guess every Duke has his hazzards.
I don’t think Ann was deliberately misleading. More like she just believed everything she was told and then copied and pasted. Are you there Ann?
My you are being allowed out on a regular basis Alex. But the clincher is that you are using exactly the same bait as your dopey creator and trying to get Libby to bite. Poor Ann, now she doesn’t have a mind of her own! Feather in the cap for a bit of originality and now trying to bait Ann too. Black eye for continued harrassment of women contributors. So Mottish.
Mott I have shown humility here before, but you choose to ignore this. I notice that you have not had the good grace to concede that I was also correct. What a surprise. One thing I have always said about you, and which you continue to prove true, is that when someone accuses you of a particular behaviour, you then accuse them of it, as if you are somehow being original. It is the sign of a very childish mind, but you can’t seem to control yourself. I wonder why you do it?
>What? Not a word from Libby? or Wu? Or any of the other defaming whale wallies on this blog?
Now, now Mott. Just because you have nothing to do with your life but post stupid comments here is no reason to be jealous of others. But because these people have obviously decided you are a complete loser and not worth indulging, you prove a good point and trying baiting for them!
>Once again, the green zealots have done their cause a disservice due to their almost pathological need to to go right over the top with silly exaggeration and clutching any lurid factoid to support their position.
Where is this Mott? The only exaggeration here is from you. There you go again…
>his animosity towards me to completely cloud his perceptions to the point where he starts to imagine excuses for highly defamatory attacks.
Any perceptions I have of you are from your own doing, and as a quick flick through other posts over the years will show, I am not alone in this.
So now travis would have us believe that requesting a response to a serious inconsistency in Ann’s original post amounts to “continued harrassment of women contributors”? I suppose any cop-out will do at this stage of the game.
The silence of all the other whale wallies is deafening. It is the classic blog equivalent of “gosh, is that the time? got to run, check you later”.
” we still await Ann’s explanation of how and why a 140-dB signal from a sonar is more harmful than a 213-dB signal from another whale?” – Ian
Hi again,
Sorry for the delay , but all these questionas are very complex and the scientists still have much work to do .
Re humans, the human threshold of pain lies between 115 and 139 dB (SPL), depending on the frequency. At those frequencies where the auditory system, ear, is at most sensitive , it’s enough with 115 dB to experience pain , but at frequencies where the ear is less sensitive , it requires higher sound pressure level to experience the same pain level.
To be continued….
Part II:
One assumption is that animals are most vulnerable to TTS ( temporary threshold shifts) at frequencies of their greatest hearing sensitivity .
For example, baleen whales , this suggest low-frequency sensitivity and for smaller cetaceans , mid – and high -frequency sensitivity.
To be continued…
Ian actually poses a relevant question.
He raises the question why marine mammals ( apparently) do not damage their hearing by their own sound production ( for example , blue whales communicate with each other at 190 dB at low frequencies), as both the tonal and impulsive sounds that they produce can be comparable in SPL to those to induce TTS in controlled expriments ( on bottlenose dolphins).
Part IV:
It appears that there are internal mechanisms that protect an animal from its own vocalisations.
For instance , the pterygoid sinus cavities of odontocetes may be positioned to shield their inner ears from their own production.
LOL!Thanks Travis for your support ( even if you’re allergic to horses, you seem to be the knight on the white stallion :)!
Thanks for a 2/10 response, Ann. If blue whales communicate at low frequency (how low?) and at 190-dB then their sounds would still be close to 190-dB as far as 100km away. So lets rephrase the key question again.
How can low frequency sonar at 140-dB at 100km distance be worse than low frequency Blue whale sounds at 190-dB at the same distance?
Part 1 human ear pain threshold is not relevant to whales in water.
Part 2 Generality, nothing specific, speculation.
Part 3 partial information, nothing specific on bottlenose D.
Part 4 Fine, but what about the same signals from other animals in their pod?
Can do better.
“Navy asks judge to clarify whale rules
By AUDREY McAVOY – Associated Press Writer
HONOLULU –The Navy on Tuesday asked a federal judge to clarify and modify an injunction placing restrictions on the service’s use of sonar in Hawaii waters.
The U.S. Pacific Fleet said in a statement that it will go ahead with planned anti-submarine warfare exercises this month in accordance with an order issued late last month by U.S. District Judge David Ezra.
Officials will then determine whether to seek additional clarifications and modifications.
“If we determine the restrictions impede our ability to conduct realistic training and assessment, the Navy will report these concerns back to Judge Ezra and ask for necessary relief,” said Capt. Scott Gureck, U.S. Pacific Fleet spokesman.
Ezra’s injunction says the Navy cannot conduct exercises within 12 nautical miles, or 13.8 miles, of Hawaii’s shoreline. That’s where species that are particularly sensitive to sonar, such as the beaked whale, are found.
He also ruled the Navy must look for marine mammals for one hour each day before using sonar and employ three lookouts exclusively to spot the animals during sonar use.”
http://www.thestate.com/361/story/343632.html
Ian,
This was my last post on this thread as I’m not very familiar with bioacustics ….as a whole this post was only meant to give a the issue a big picture overview….
Ian Mott wrote:
>It should also be pointed out that the pain level in a human ear (130Db) is a lot less than what would apply to a hearing system based, not on a thin membrane in a gas, like ours but, rather, a jawbone in liquid, like theirs.
Ian Mott then wrote:
>Part 1 human ear pain threshold is not relevant to whales in water.
Ann, read back through this thread (and all the others), and NOTHING you write will satisfy Mott. Isn’t it delicious that he is even scoring your comments now, like a good little school girl doing her homework for a dirty, fat old man.
Blue whales produce sounds at around 15Hz, fin whales around 20Hz, Bryde’s whales between 124 and 900Hz, minkes between 100 and 2000Hz.
Can we make it a dun tobiano stallion Ann?
So Ann is refusing to substantiate the claim she made in her first post. She provided a standard green movement “assembly line factoid” about the decibels of long range sonar but has completely ducked for cover when asked to explain why even louder signals, made by many marine species for millions of years, and generally made in the reasonably close proximity to other animals, do not pose a similar, or even more serious, threat to the one being attributed to sonar.
And as usual, she has relied on her so-called “white knight”, (read, village idiot on a one-eyed donkey), to make cheap personal slurs to cover her backside. And to top it all off, the information provided by Travis on whale sound frequencies merely confirms that their high decibel signals use the very same low frequency, long distance band widths as most sonar. Thanks for the help, “Sancho Panchez”.
Ann, you have been tested and this historical record of fact has established that you have been found wanting. The posting of a news item, highlighting the way similar misinformation to yours has made it into the court system, will not obscure the fact that neither yourself, nor any of the other self proclaimed whale experts on this blog, have been able to substantiate one of the key planks of your ideological position.
Thank you, for the opportunity to do a very useful bit of work in the name of truth.
Big spank on the bottom for you Ann. And I bet Grott would like that – remember his daliance with the Scandinavian women he told us all about a while ago? Ergh! At least he can go away happy in his delusion.
>Ann, you have been tested and this historical record of fact has established that you have been found wanting. The posting of a news item, highlighting the way similar misinformation to yours has made it into the court system, will not obscure the fact that neither yourself, nor any of the other self proclaimed whale experts on this blog, have been able to substantiate one of the key planks of your ideological position.
What a crock! Are you that a) stupid b) full of yuorself Mott? It makes no difference that cetacean researchers, acousticians, government organisations, NGOs, veterinarians, the US NAVY and solicitors and judges recognise mid and low frequency sonar as a threat to marine mammals. Mott is right. He speaks in the name of truth. He is the expert. LOL!
Of course overlooking the startle theory, gas bubble theory, that cetaceans do not necessarily sceam at one another when they are in close proximity and other evidence presented here is meaningless. The fact people who know better choose not to indulge in Mott’s sadistic behaviour has nothing to do with it either. You live in your own megalomaniacal world Mott – one we don’t want anything to do with. What a freakin’ loser!! What a freakin’ freak!! What an evil prick that just wants to disrupt a good post because he has issues with certain individuals, thinks it’s cool to argue any point, and hates being proven wrong and stupid.
Right on time, and as expected, Travis. Still refusing to address the key issues but never reluctant to go completely over the top with personal abuse.
I’m terribly sorry for “disrupting a good post” with some inconvenient facts that the readers have a right to know. Thats the trouble with blog readers, Travis, as graeme Green said, “they got no damned gratitude”.
Ian Mott-
What is your problem? You just don’t get it do you? I don’t particularly support Travis’s talk, but he at least manages to post facts. All I’ve ever seen from you is grandstanding on a soggy cardboard box. There has been been plenty of evidence posted here by Ann Novek, Travis and others, but for some reason you ignore it and make up your own crap. You’re a chalatan and a waste of space. Piss off or drop dead.
It seems to me, Motty, that these people are offended by the fact that someone might express a different view to their own on “their” blog. Perhaps they think they are still on the ACF or Greenpeace site where they can have endless one sided conversations with themselves without fear of contradiction.
So perhaps Roger Grace would like to explain why low frequency sonar at 140-dB is a threat to marine species while 213-dB at the same low frequency from another whale, just as they have done for millions of years, and closer, is no threat at all?
Gaarn, Roger, show us some substance. All you ever do here is post abuse.
Alex McAdam-
I am inclined to agree with the view that you are Ian Mott. There is no point in engaging with you. I post information when it is warranted, but you have proven there is no point. You ruin what is otherwise a good blog.
Yes, Alex, it is as if these people think they are in some sort of reality TV version of “survivor blogosphere”. With mincing, vacuous environmental barbiworlders who do ersats intellectual stunts in the hope of earning some sort of immunity from scrutiny for their tribal beliefs.
And all they have to do if someone doesn’t fit into their urban green bimbo stereotype is have a little meeting between themselves and vote them off the blog. This Roger Grace clown seems to think his role in this show is to swan in at the end and announce, with all the preposterous gravitas that he can muster, that “the tribe has spoken”.
Well guess what fellas. This is a public forum. And in the real world all you succeed in doing is demonstrate that, deep down, you are just a bunch of little closet eco-fascists who think all they need to do to get their way is stomp their feet and mummy will make it all right again.
You entered a contest of ideas with nothing but half baked factoids and demonstrated, once again, that the cruelest thing one can do to a fool is to let him speak his mind.
So I bid you adieu, folks. I am off to the farm to savour the fruits of honest toil, rational thought and common sense.
>vacuous environmental barbiworlders
You’re a chauvanistic pig Mott. You will be reminded of this comment. This is a public forum Mott, and in this world there are still ethical codes that must be adhered to.
>that the cruelest thing one can do to a fool is to let him speak his mind.
You said it idiot fat boy.
>So I bid you adieu, folks. I am off to the farm to savour the fruits of honest toil, rational thought and common sense.
No truer words finally spoken – off to the funny farm to talk delusion with the other nutters.
Do you reckon Motty goes to rhetoric classes. Do you think he wanders around the house talking like that?
“mincing, vacuous environmental barbiworlders ” – But surely enviro-barbieworlders don’t eat mince?
I reckon it would be hot to meet an “urban green bimbo stereotype”. Would be even hotter to meet one in a closet if you were an “eco-fascist”. Unless of course you were Motty and were unable to get your inflated ego into a closet.
So what does a UGBS look like. Would they be dressed in army fatigues with some nice lippy, corporate legal style, or just a nice frock?