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Beachings linked to military low-mid frequency active sonar

Mass beachings have been associated with active sonar have occurred in Madeira (2000), Greece (1996), the U.S. Virgin Islands (1998, 1999), the Canary Islands (1985, 1988, 1989, 2002), and, northwest coast of the United States (2003).update: court blocks sonar 7/6/06

Reference: http://www.nrdc.org/wildlife/marine/nlfa.asp

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LFA is low frequency active sonar

LFA stands for Low Frequency Active sonar, a technology used by submarines to "see." Unfortunately even one hundred miles from the source of a LFA source animals experience the equivalent of decompression sickness, killing every dolphin, porpoise, orca, and whale within 100-300 miles, depending on the decibal. It's no good for humans either.

Reference: http://www.nrdc.org/wildlife/marine/nlfa.asp

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Animal sonar, echolocation, and noise pollution

Whales and dolphins have a tool called echolocation, a sonar which allows them to "see" their prey, even it's internal workings! Noise pollution in the water has a significant effect on whales ability to navigate, hunt, locate their pods, and reproduce.

Echolocating animals have two ears positioned slightly apart. The echoes returning to the two ears arrive at different times and at different loudness levels, depending on the position of the object generating the echoes. The time and loudness differences are used by the animals to perceive direction. With echolocation the bat or other animal can see not only where it's going but can also see how big another animal is, what kind of animal it is, and other features as well.
- wikipedia

Many modern submarines use their own sonar a low and mid-frequency sonar is so deafening the pressure waves affect animals on the cellular level, causing the equivalent of "the bends" or decompression sickness. For animals with echolocation this causes sonar function to fail and leaves these animals blind, if they're lucky. What often results is massive beachings (update: court blocks sonar 7/6/06)


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