Posted on 03/06/2005 11:59:28 AM PST by NoCmpromiz
The Navy and marine wildlife experts are investigating whether the beaching of dozens of dolphins in the Florida Keys followed the use of sonar by a submarine on a training exercise off the coast.....
A day before the dolphins swam ashore, the USS Philadelphia had conducted exercises with Navy SEALs off Key West, about 45 miles from Marathon, where the dolphins became stranded....
Navy officials refused to say if the submarine, based at Groton, Conn., used its sonar during the exercise.
Some scientists surmise that loud bursts of sonar, which can be heard for miles in the water, may disorient or scare marine mammals, causing them to surface too quickly and suffer the equivalent of what divers know as the bends — when sudden decompression forms nitrogen bubbles in tissue.
(Excerpt) Read more at news.yahoo.com ...
It's a proximity thing. Like being IN the Nissan next to you vibrating from the bass instead of being in the car next to it just being annoyed.
This is correct.
Let's walk through this using the information given. USS Philadelphia doing traning mission with SEALS near FL Keys. Now, the advantage of a submarine is undetectability. Most SEAL missions are covert. Neither the submarine nor the SEAL team(s) are very interested in turning on spotlights and dye markers and other attention-getting devices to advertise their position. This would, in time of conflict, be an open invitation that says "Here we are, please blow us all to Hades..." Since a training mission will be a simulation of actual wartime conditions, you can rest assured that the USS Philadelphia was NOT using (here's the operative word) ACTIVE sonar during this exercise. They were most assuredly using sonar however. The inactive variety. Like sticking a microphone in the water and listening...
Now there's a thought. All those dolphins beached themselves because they weren't informed that it was kareoke night and they all got mike-fright and ran towards shore....
That's the truth! I was assigned to 3 different subs during my time in the Navy. In that time I spent perhaps 2 years total at sea on the different boats. I heard active sonar sounded exactly once during all that sea time; it was on my last boat, which I had helped put into commission, during initial sea trials and 'shakedown' cruise just to make sure the system worked. It's as others have said: boats just don't use active sonar as a matter of course during peace time.
Like you, I find it hard to descibe the sound produced; it varies in both pitch and loudness, and may have just a single frequency or several varying notes combined to make a truely wierd changing 'chord'. It's like some sort of demonic combination of a pipe organ and a steam calliope - both more powerful than anything you've ever heard.
What do you think they do in the X-file division of the FBI?
Good points, of course.
Then again, most SEALS tend to get very upset when the innerds are blasted into quivering bits of bleeding jelly by their own submarine's active sonar when they are swimming outside the boat.
And you really don't want a bunch of very upset, very mad, bleeding SEALS swimming around outside your boat. At night.
It's a sign of aging and yes, I have that same problem.
It is true that a transducer's ability to put energy into the water is limited by the cavitation and all, but they are using huge arrays of transducers that can be focused by constructive and destructive wave interference. The can send a focused beam of sound energy just as a phased array radar set can focus radio energy. That is what they were doing twenty years ago -- who knows what they got now.
But that's their business, not mine. They keep me safe, and I pay some taxes. Good deal.
Hmmm! So if you dangled a messcook off the end of the sailplane into the water would that make him ...
...Pogy-bait?
(Groan)
Ticks me off a bit that they blame the Navy automatically, and have no real hard concrete evidence from which to come to a conclusion.
All they know is that the day before there'd been an exercise in the area, and then the dolphins beached the day after.
That's pretty darn thin evidence wise.
It seems to me that these beaching events are due to poor leadership in a herd/pod mentality.
The Navy should make sure old copies of the NY Times, LA Times and Washington Post will no longer be jettisoned with the garbage. Tough call but environmentally sensitive.
Then again, their leadership might have viewed a jettisoned copy of Fahrenheit 911...
I've seen large predators beached or stranded in shallows having chased schools of fish that head there evade. Once saw a 200 lb Ulua (Trevaly) floundering in 2 ft of water in Hilo Bay. I suppose a pod of dolphins chasing smaller prey could easily be beached in this way. Since the school of small fry escaped, i.e. no evidence, the Navy and its sonar is blamed.
BTW, subs and deep draft vessels don't go that close to shore or use sonar where it's virtually ineffective.
MY theory FWIW, is that they have rabies. You know, hydrophobia. Fear of water....
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