Underwater, no-one can hear you scream...
Almost ten years ago I wrote the introduction to a small educational foundation my colleagues and I were going to set up.
According to the noted American Marine Biologist, Roger Payne, the great whales of the world have 'enjoyed' a global communication network for tens of thousand of years, gaining the benfit of a "deep sound channel in the ocean", a combination of thermal layers and currents that allowed these whales to transmit their 'songs' at a wavelength of 20hz over incredible distances to communicate with whales in other oceans.Today however, the "noise" created by human movement and activity above,below,through and with the ocean, occurs almost primarily at the same wavelength of 20hz; effectively severing what has been the worlds first truly 'global' communications network !!
As you may realise, this became the basis of the work of the Whalesong Foundation and its subsequent iterations. Yes some may say obtuse, but there is a little method in the madness!
To view how far we have come, or perhaps to measure the lack of distance covered in our journey so far, follow some of the links below. I have also included an outstanding piece from
If you want to Listen to LFAS, follow this link :
http://darwin.bio.uci.edu/~sustain/issueguides/LFA/navylfs.ra
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Feb 28th 2002 | NEW YORK
From The Economist print edition
The American navy may soon have a whale of a problem
IT MIGHT offer a plot for a Hollywood blockbuster. The usual suspects are present: evil military types, a plucky band of environmentalists and a cast of loveable animals fighting for their survival. The story is spoilt, though, by the fact that the would-be heroes of the dramaearnest biologists trying to make the truth heard over the political frayare still off in a corner arguing with each other over the scientific evidence.
The loveable animals in question are the world's whales. At stake is the American navy's use of a new form of sonar. For the past two years, it has been trying to get permission to deploy low-frequency active sonar (LFAS), a system designed to hunt for very quiet submarines. But the frequency range of LFAS (100-500Hz) is the same as that used by baleen whales (blue, grey, fin and humpbackthe most charismatic species) in their songs. Biologists worry that LFAS might thus damage these whales in some way. That would make its use illegal under an American law from which not even the navy is exempt. In the next couple of months, the National Marine Fisheries Service (NMFS), the agency responsible for protecting the welfare of marine mammals, is due to announce whether it will let the navy deploy the new device. It's decision, one way or the other, is sure to infuriate somebody.
Sounding the depths
The reach of the proposed system is remarkable. Because of the distance that low-frequency sound waves can travel under water, a set of four ships emitting sound at 235 decibels could monitor 80% of the world's oceans for submarines. But it is precisely that reach which, from the whales' point of view, might be worrying. So, in 1997 and 1998, the navy gathered data on the response of whales to an LFAS test array. Kurt Fristrup, a marine biologist at Cornell University who helped to conduct this study, says humpback whales exposed to LFAS altered the lengths of their songs slightly, but resumed normal calling a few hours afterwards. Grey whales exposed to a test source in the middle of their migration path altered their routes to avoid it, but once the source was moved out of the migration corridor and further into the ocean, they appeared to ignore it.
That does not sound much to worry about, and in any case, the navy says the system can be made safe. It has been designed to switch off as soon as a broadcasting ship comes within 1km of a whale. At this distance the animal would hear the sonar at a volume of 180 decibels, which the navy says will cause no harm.
Some whale experts, however, disagree with the navy's boffins. Lack of alteration does not imply lack of injury, according to Naomi Rose, a marine biologist at the Humane Society, an American animal-welfare charity. The animals could have been disturbed or even partially deafened, but their mating and migrating activities may have been too important for them to change their patterns of behaviour. More pertinently, the navy's test array broadcast at a maximum level of 155 decibels. That is roughly 0.3% of the power of the 180-decibel cut-off point that the operational system would have.
Meanwhile, greens are fretting not only about the whales, but also about the vigour of the agency appointed to protect them, which they fear is the victim of regulatory capture. According to Michael Jasny of the National Resources Defence Council, an environmental lobby group, the best available science has shown that LFAS causes severely adverse effects in marine mammals. The NMFS would have to tie itself in knots to come up with a determination supporting the navy.
Dr Fristrup, though, doubts if more studies and more tests could assuage the fears of whale-lovers. Certain groups, he says, oppose LFAS deployment on principle: their positions are clearly not susceptible to change based on any scientific evidence that can be developed.
Feb 28th 2002 | NEW YORK
From The Economist print edition
Last update:
23/7/04; 9:43:33 AM
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