LOFROBLTBA!!!
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BigJetDriver69 once bubbled...
adder70 once bubbled...
I believe the "blythe assertion" is the the sound pressure level in dB, is 160 dB at 160 km away.
Unless you have actual test results to show, your statement is, unfortunately, just an unsupported assumption.
As is yours.......
In fact, at the source the sound is up to 240 decibels, which is 100 million times more powerful than the 160 decibels at 160km cited in the article (similar to numbers that I've seen in other articles as well).
I understand your aversion to unsubstantiated assumtions and your reluctance to base an opinion on this article alone. It was sloppy and speculative. However I would urge you to read up on it. There are many reputable organisations documenting the problems with LFA, including NATO and the US Navy who have both reached the conclusion following various incidents of stranding that LFA was the culprit. In a case in the Bahamas what I understand is that they didn't even have the system turned up all the way and still some of the animals were bleeding from their eyes and ears, indications of not only acoustic trauma but also physical tissue damage. Other tests have shown behavioural changes in whales, including cases of sperm whales unable or unwilling to dive (and therefore eat) for days after an LFA blast. The body of evidence is large, growing and verified by both "sides". We don't have to worry too much about making unfounded assumptions about this any more.
R..
jiveturkey once bubbled...
I guess at this point they don't really know what's going on. They have to come up with something that's probable. Do you have any other ideas as to how this would happen?
As you said, because of evolutionary mechanisms, this isn't a natural occurance for whales (groups of whales at that). These bubbles in their systems aren't normal either or whales would have been gone long ago. There has to be something unnatural happening regardless of whether or not it's sonar "scaring" them to the surface.
Knavey once bubbled...
This is the same old "theory" crap that has been going around since the stone age...
Throsh: "See little rock. Fits on end of stick. Stick animals with it and get food"
Natureluver: "Throsh bad. Kill all animals with rock stick."
Throsh: "You so unoriginal...its not rockstick...it called spear!"
Natureluver: "Spear? Spear bad...you kill all animals and none left!"
Throsh begins to think he should stick Natureluver instead of a deer with spear. About that time the sabertooth tiger happens along.
Who do you think lives to see the next meal? Will Natureluver survive the onslaught of a hungry tiger? Will the sabertooth tiger make a meal out of our outspoken activist AND our spear equipped inventor? Or will the saber tooth tiger AND Throsh go their separate ways...the saber tooth tiger with a full belly and Throsh with his spear to find something else to eat since cannibalism isn't his thing? Or will Throsh chase the tiger away, saving poor activist so that he can plant more trees?
We report...you decide.
Diver0001 once bubbled...
As is yours.......
There are many reputable organisations documenting the problems with LFA, including NATO and the US Navy who have both reached the conclusion following various incidents of stranding that LFA was the culprit. In a case in the Bahamas what I understand is that they didn't even have the system turned up all the way and still some of the animals were bleeding from their eyes and ears, indications of not only acoustic trauma but also physical tissue damage.
R..
rickg once bubbled...
Diver0001,
What you forgot to say was that the only USN Low Frequency Active (LFA) equipped vessel was not only NOT TURNED UP ALL THE WAY - IT WASN'T EVEN IN THE ATLANTIC OCEAN. This stranding can not be attributed to the USN's LFA.
That said, there was a naval exercise going on when this stranding occurred and there were multiple surface vessels (destroyers, frigates, etc) transmitting medium/high frequency sonars in a constricted area which may well have contributed to the stranding.
Rickg
rickg once bubbled...
I know the US Navy has adopted some new procedures in an attempt to minimize the possibility of future occurences and is also continuing to research this issue.
Rickg
saying once bubbled...
Out of curiosity: are there physiological dangers for someone to freedive to 100 feet, exhale, and then take a breath from a reg sitting there waiting for them? That is, is there a risk in changing lung volume that quickly?