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Dolphin Death Mystery
- Thread starter AAP
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Delinquent
Well-known member
Shit, my wife and I will be there in July. Looks to be on the northern coast and we're on the southeast coast so it should be ok. I read that the Zanzibar dolphins are ok as these were migrating dolphins
megamania500
New member
gotmilk said:
This is usually the case, even though you won't hear it mentioned in the news. Remember, dolphins and whales communicate through sound and submarines are using sonar, and submarines being in the vicinity of beached whales has been documented. I saw this on the learning channel.
Pride Fighting Fan
New member
Those damn trouble making dolphins had it coming. lol
megamania500
New member
redguru said:
(AP) 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.
More than 20 rough-toothed dolphins have died since Wednesday's beaching by about 70 of the marine mammals, Florida Keys National Marine Sanctuary spokeswoman Cheva Heck said Saturday.
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.
"This is absolutely high priority," said Lt. Cdr. Jensin Sommer, spokeswoman for Norfolk, Va.-based Naval Submarine Forces. "We are looking into this. We want to be good stewards of the environment, and any time there are strandings of marine mammals, we look into the operations and locations of any ships that might have been operating in that area."
Experts are conducting necropsies on the dead dolphins, looking for signs of trauma that could have been inflicted by loud noises.
©MMV, The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.
Or it may be submarine-finding equipment:
LONDON, March 4 Reuters - NATO tests of an underwater sonar system could have caused a mass stranding of whales off the coast of Greece, scientists said today.
Twelve Cuvier beaked whales, a deep diving breed that is rarely stranded, washed up on the west coast of Greece in May 1996 just days after the North Atlantic Treaty Organisation tested a Low Frequency Active Sonar (LFAS) system used to detect diesel and nuclear submarines.
Alexandros Frantzis, and colleagues at the University of Athens, think the two events are more than just a coincidence.
"We know that LFAS was used in the Kyparissiakos Gulf. We also know that no other LFAS or mass strandings have occurred in the Greek Ionian (Mediterranean) Sea since 1981," he said in a letter to the scientific journal Nature.
"Taking the past 16.5 year period into account, the probability of a mass stranding occurring for other reasons during the period of the LFAS tests is less than 0.07 per cent."
The LFAS generates very loud, low-frequency sound which enables long detection ranges. Although its effect on whales has not been studied thoroughly, many specialists think that at high levels it could physically damage the whales and affect their behaviour.
Mass strandings of the creatures are extremely rare. Since 1963 there have been only seven cases worldwide of four or more whales and three of them occurred near the Canary Islands during similar military manoeuvres.
The latest stranding was also odd because the animals were not stranded together, but over a 40 kilometre area. Deep diving whales also seem especially affected by low-frequency sounds, even at low levels.
Frantzis said that more information is needed to solve the mystery, but unfortunately most of the data about the use of LFAS are a military secret.
redguru
New member
megamania500 said:
The US Navy Acoustical range in the Bahamas is used for sonar testing. That I will allow. However, the area is swept for biologics by sight and by passive sonar before any test of active sonar. A sonar operator can hear whales and dolphins for 10's of nautical miles. Also since that article was posted in 2005, I'm sure the necropsies are complete on the dolphins and if there were any findings of aural damage we would have been notified by now.
Also when a sub is doing maneuvers with divers in the water, you really think they are going to use thier active sonar?
I used to have to make this page over the 1MC every 15 minutes when divers were in the water. "There are men working over the side. Do not rotate screws, cycle rudders, take suction from or discharge to the sea, or operate any underwater electrical equipment while men are working over the side."
As for the other article, LFAS uses frequencies from 30-300 hz. Extensive testing has been done on the effects low frequency noise on aquatic life. No known adverse effects were ever noted. That article was from 10 years ago, no follow up investigation ever done?
Creepusmaximus
New member
redguru said:
War ships use active sonar and I would bet a lot that's what happened to the dolphines. The latest sonar seems to be a killer for dolphines and whales.
redguru
New member
Creepusmaximus said:
I would bet and I have evidence are two different matters. Fast frigates and destroyers can use active sonars to prosecute submarines. They aren't used in SOP because it gives away the location of battle group pickets. They prefer to prosecute possible subsurface contacts with dipping listening sonars deployed by thier helicopters or aircraft dropped sonobouys with that data uplinked to the rest of the battle group.
megamania500
New member
redguru said:
Washington Post article on research brought on by Canary Islands whale beaching incident in September of the previous year:
Navy Sonar Affecting Whales
By Marc Kaufman
Washington Post
Wednesday 08 October 2003
High-powered sonar from Navy ships appears to be giving whales and other marine mammals a version of the bends, causing them to develop dangerous gas bubbles in some tissues and blood vessels and to beach themselves and die, according to a study published yesterday in the journal Nature.
Reporting on beaked whales that were stranded in the Canary Islands soon after an international naval exercise last year, researchers for the first time found a condition similar to decompression sickness in 10 of 14 dead animals.
The new data begin to explain how and why high-decibel mid-frequency sonar used by the U.S. Navy and other military fleets appears to cause some deep-diving marine mammals to die. Although the bends was previously unheard of in whales, dolphins and porpoises, the British and Spanish researchers concluded that a marine mammal version of decompression sickness was "the most likely cause" of the Canary Island strandings.
"This is the best data we've ever seen from a sonar-related stranding," said Roger Gentry, coordinator of the National Oceanic and Atmospheric Administration Fisheries Acoustics Team. He said NOAA will hold a workshop this year with the authors and others in the field to assess the new information and try to reach scientific conclusions.
The new research from the Canary Islands suggests two possible explanations for how the gas bubbles harm the whales. One is similar to the way humans get the bends: The whales panic at the sound of the loud sonar noises and rise too quickly from deep water. As they rise, nitrogen bubbles can be formed from the rapid change in pressure and cause the bends. The other hypothesis involves bubble formation caused directly by the sonar on gas nuclei, or bubble "precursors," in whale tissues that are already highly saturated with nitrogen.
Gentry said the scientific community remains skeptical that rapid ascents are causing the bubbles to form. "From an evolutionary point of view, it does not seem likely," he said. "Whales have been diving like this forever, and should have evolved mechanisms so they wouldn't succumb to decompression."
The Canary Island strandings and research involve mid-frequency (or pitch) sonar coming from Spanish-led, international naval maneuvers that included only one American destroyer. But they could affect a contentious debate over the U.S. Navy's desire to deploy very loud low-frequency sonar around the world to detect "quiet" submarines. That effort was stopped in August in California by a federal magistrate who said the government had violated environmental laws in giving the Navy permission to deploy the new sonar globally.
"We know there is a connection between military sonar and strandings, and now we're making progress on the physical mechanism causing them," said Joel R. Reynolds, an attorney with the National Resources Defense Council, which sued the government over the low-frequency sonar. "This is very compelling scientific evidence."
Lt. Cmdr. Joseph A. "Cappy" Surette, a Navy spokesman, said officials are still studying the Nature article. But he said the Navy takes many steps to avoid harming sea creatures and that the new sonar technology is necessary.
"Submarines are becoming an increasingly serious threat to the U.S. Navy," he said. "Diesel submarines have become increasingly difficult to detect and are proliferating around the world."
He also said that "there is no evidence of any negative impact on marine mammals" in areas where the new low-frequency sonar has been tested.
The legal problems faced by the new Navy sonar system, called the Surveillance Towed Array Sensor System -- Low Frequency Active (SURTASS-LFA), have upset some in Congress and helped spur successful efforts to pass legislation to limit the reach of environmental laws that affect the Defense Department. The legislation, part of the Defense Department appropriations bill, is in conference. The House language broadly exempts the Defense Department from provisions of the Endangered Species Act and the Marine Mammal Protection Act, while the Senate language is considerably less limiting.
Several mass beachings of whales and dolphins have been tied to high-decibel sonar since the phenomenon was first identified in 1996, and Navy researchers are going back to see whether other strandings can be connected with nearby Navy sonar use.
Whales and other marine mammals are highly sensitive to sound and use it to communicate. Different species hear at different frequencies, and so are affected by various kinds of sonar. The low-frequency sonar that the Navy wants to use around the globe operates at the sound level used by the largest, and some of the most endangered, whales.
The whales stranded in the Canary Islands are beaked whales, the same kind killed in a similar stranding involving sonar in the Bahamas in 2000. Beaked whales are relatively small and dive deeper than most to feed on squid.
The Navy initially said that its sonar had no connection with the 2000 stranding, but a later inquiry ruled out all other possibilities and concluded the sonar most likely caused the deaths.
The research published yesterday in Nature was conducted by scientists at the Zoological Society of London and the University of Las Palmas de Gran Canaria in Spain. The English researchers also reported that six dolphins and one beaked whale that had stranded along British shores between 1992 and 2003 had gas bubbles in their blood vessels.
I know that naval ships and planes don't go around blasting their active sonar 24//7, and a sub will use active sonar maybe only after they know they've been found. There's alot of groups on the 'net declaring that the military stop using sonar because its killing and damaging sea life. I would see those as biased, so I try to find unbiased journalism regarding this topic. On the other hand, I think that if everytime the military used active sonar and it killed whales dolphins and porpoises, there would be dead sea animals all over the place.
Now, if someone wants to refute these articles that I've copied and pasted, don't expect a response from me. All I did is say is that I heard that sonar afftect sea animals on the learning channel. Now, because of that, I've found myself looking for crap regarding this topic on the net, and I never had much interest on the subject in the first place. So instead of wasting more time on the subject, and surfing around at stuff i really want to look at and read, here's my response beforehand:
OK, I believe you. You won. case closed.
Creepusmaximus
New member
redguru said:
They have new rules about using sonar coming into harbors because of killers whales being killed and jumping out of the water up in Alaska. At least that's the story I got. They use the sonar more than you think.
redguru
New member
AAP said:
You could damage his inner ear. He's normally working within feet of the hull. Look, I know that sonar can hurt marine life, but the Navy is extremely sensitive to this. The sonar crew on board both surface combatants and submarines is always listening for the presence of "biologics". The only sonars I know of that are damaging out further than a nautical mile would be mine detection arrays.
As far as the repid decompression damage to the whales, that can also be caused by a very normal phenomenom, known as outgassing methane from the sea floor. When the school swims over the vent, they lose bouyancy and sink to depths they normally couldn't swim at. Then they rise too rapidly to get air causing "the bends" or nitrogen bubbles in thier blood.
redguru
New member
gotmilk said:
Our ears can't pick up the high higher frequency sonars used in depth-finding and proximity alarms, but those are normally much lower power and directional anyway. You can hear sonar in use by a destroyer below decks on a neighboring ship. Also the ELF communications used in 3-30 HZ range and the lower end of the LFAS sonars band is outside our hearing as well.
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