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Underwater Sonar Linked To Whale Deaths
An anonymous reader writes "A group of scientists have confirmed a link between the sonar used by Exxon Mobil to map the ocean floor for oil and the death of melon-headed whales. From the article: 'A spokesman for ExxonMobil said the company disagrees with the findings. "ExxonMobil believes the panel's finding about the multi-beam echo sounder is unjustified due to the lack of certainty of information and observations recorded during the response efforts in 2008," spokesman Patrick McGinn told AFP in an email. He added that observers employed by the Madagascar government and the oil giant "were on board the vessel and did not observe any whales in the area."'"
We can only use overwater sonar from now on.
"ExxonMobil believes the panel's finding about the multi-beam echo sounder is unjustified due to the lack of certainty of information and observations recorded during the response efforts in 2008," spokesman Patrick McGinn told AFP in an email. He added that observers employed by the Madagascar government and the oil giant "were on board the vessel and did not observe any whales in the area."'"
Certainty of information: Nobody requires absolute certainty in science. In fact, even the court system, sad as it is, needs it -- it requires "beyond reasonable doubt", whereas science is similarily situated at "best model that fits the facts". Type of cognitive distortion ExxonMobile uses here: All-or-nothing thinking.
Out of date observations: It's 2013 now. By carefully hand picking your data set to be only, say, 2008, or pre-2008, you are discounting everything that came after. One supposes that an extra five years' worth of observations, we'd be able to narrow in on a cause. But let's humor them and take just 2008. In February of that year, before the incident in question, the US courts found there was enough evidence that high energy sonar was killing whales to ask the military to reduce its use in naval operations.
Impartial observers: Let me sum this one up real easy -- "Managment finds no problem with the management." The government was paid a lot of money to go along with Exxon, and employees of Exxon I think we can safely say aren't impartial observers. So one of the most basic things required for proper fact gathering went right out the window. This is, in effect, an admission that ExxonMobile has no valid data points from which to draw any conclusions whatsoever. It is, from a scientific perspective, pure speculation. "We're not wrong because, er, we saw ourselves doing nothing wrong." Okay... what about everyone else? "We didn't ask them."
#fuckbeta #iamslashdot #dicemustdie
"We're no worse than anyone else and you can't prove otherwise"
If you read the actual report, you'll see these statements:
"There is no uneqiovocal and easily identifiable single cause of this event,"
"This is the first known such marine mammal mass stranding event closely associated with relatively high-frequency mapping sonar systems,"
"MBES systems (similar) to the 12 kHz source used in this case are in fact commonly used in hydrographic surveys around the world over large areas without such events being previously documented."
"There may well be a very low probability that the operation of such sources will induce marine mammal strandings,"
Except there's a solid causal mechanism in play here. Whales are known to have particularly sensitive sound-receiving organs that also also known to be sensitive to extremely loud sounds like explosions and sonar. And it just so happens that someone was using a highly focused sonar in the time and space these whales turned up dead.
By your logic, a guy going into an auditorium and shooting a bunch of bullets isn't necessarily the cause of all the people found dead there with bullet-holes in them. There's just not a cause and effect relationship... sure, it's a plausible explanation, but that's far from being 'cause and effect'.
I spent three years sailing on the Scripps Institution of Oceanography research vessels, mostly the Revelle, and the Melville. One of my primary responsibilities was operating the multibeam sonar and other acoustic instruments. Working on ship is interesting, it's sort of like college, where you live in one small floating building housing the dorms, labs, cafeteria, and plant, with 40 people, except you cannot leave the building for 50 days at a stretch. It's like being on a reality show living and working with scientists of all types, and some other colorful characters.
None of the 50 or so marine biologists that I ever sailed with ever had the slightest concern about the multibeam's impact on marine life. And belive me they were very interested in sonar's effects on marine mammals. Anytime we would perform SEISMIC survey ops we were required by law to have a marine mammal observer on watch. If they sighted any whales in the area, we shut down the air guns. In the old days they used sticks of dynamite, now they use 3000psi air guns. Loud.
Bear in mind our ship cost up to $50,000 per DAY to operate. And that's just for the ship, crew, and technicians, not the scientists and who or what ever they bring. Commercial vessels probably cost much more to operate; the greatest cost is diesel; ships burn thousands of gallons per day; we bought ours from the Navy. But the MMO's were professional scientists and took their jobs seriously and we respected them and I would call them my friends. The idea that any of the other acoustic instruments could harm marine mammels was never broached. Another time I sailed with a large group of marine biologists who were basically pinging whales with high powered sonar to see what would happen because they were concerned with high powered sonars effects on whales. They never brought up any of the ships other acoustic instruments.
It's possible that MB has an effect. You could hear our MB all over the ship. We ran a Simrad EM-120 at 12khz, which I can hear pretty well. It sounded like a really loud bird chirping. And sometimes you could even hear the tinkling echos off the seabed. I can see how it MIGHT annoy whales. And I bet the commercial ships run a much higher-power sonar. They drag like 12 airguns when we drag one or two. I think a lot of it also depends on where you're operating. Most of the ocean is surprisingly empty and devoid of higher life forms. Perhaps greater percautions are needed close to whale populations. It's just surprising because as a member of the oceanographic community I for one was not aware that this issue was even on the radar (no pun intended).
MB sonar is generally a "good thing". We can only get very coarse bathymetry via satellite. MB is necessary to map the seabed in any detail and seabed maps are critical to earth science. I just hope this doesn't turn into some sort of sonar hysteria where we are unecessarily restricting good scence based on bad science.
-73, de n1ywb
www.n1ywb.com