This is the VOA SpecialEnglish Environment Report.
American officials have approved a plan for the United StatesNavy to use loud, low-frequency sound wave devices on two ships inthe world's oceans. The new sonar system will be used to search forespecially quiet submarines. The device works by sending sound wavesthrough the water. When the sound waves hit an object, its presenceis confirmed.
The new sonar system can find objects ten times farther away thanthe sonar used now. The Navy plans to use the new system in eightypercent of the world's oceans. The noise from the sonar device isabout as loud as a large airplane leaving the ground.
The Navy has permission to use the new sonar system for fiveyears. Officials say the Navy will have to follow rules on when andwhere to use the sonar devices.
They say the Navy will not be permitted to use the sonar ifwhales are seen within two kilometers of the ships. The sonar alsowill be banned within nineteen kilometers of any coast.
The Navy also is required toinvestigate the possible effects of the sound waves on oceananimals. This includes the ability of whales to communicate witheach other. The officials say these measures will protect theanimals from any serious harm.
However, environmental activists do not agree. One group, theNational Resources Defense Council, may take legal action to try tostop the Navy's plans. The group criticizes putting the system intooperation before knowing its possible effects.
The National Resources Defense Council also notes that pastmilitary sonar has killed whales. Two years ago, the Navy used veryloud sonar devices in deep waters around the Bahama Islands. Morethan fifteen whales and a dolphin later were found trapped on landalong several coasts. At least six of the whales and the dolphindied.
The National Marine Fisheries Service and the Navy investigatedthe incident. Investigators said the noise from the sonar led to thedeaths of the ocean animals. They also found that all but one of thedead whales had bled around the brain and ear bones.
The Navy says the new sonar system is necessary because othernations are developing quiet submarines. It says the effect on sealife will be minor.
This VOA Special English Environment Report was written by CatyWeaver.