
Sonar signals make dolphins mistake submarines for other marine species.
(States Chronicle) – After repeated activists’ campaigns, US Navy will limit sonar signals to protect marine species, a recent press release wrote. This is the first measure that the US government is making to protect mammals, but activists think there is more that could be done.
Environmental groups have been stating for years that the military trainings that the US Navy is conducting jeopardize the life of marine species, particularly dolphins and whales. The latter get confused when hearing the sonar signals of the submarines and they get severely injured in contact with unidentified objects in the water.
Dolphins and whales use sonar signals to position themselves in the water in respect to other species or objects. This system of communication allows them to locate ships or submarines and thus, avoid incidents.
Confusions arise when marine species mistake their own signals with the sonar signals of US Navy submarines. Marine mammals mistake these for other underwater species and they swim towards them instead of avoiding them; thus, getting injured or even killed.
The most dangerous signals were the mid-frequency ones between 3 and 4 KHz, which are said to interfere with dolphins’ own signals. Unfortunately, the US Navy has to use them because the higher frequencies (7 KHz or more) they once used did not allow army officials to detect submarines. These new signals have a wider range, but they are much more harmful for the underwater environment.
Due to the new legal settlement, the US Navy will no longer be allowed to conduct sonar-based exercises along the Californian and Hawaiian coasts. These regions are highly populated by underwater species and many mammals got injured during military trainings, environmental groups have explained.
US Navy representatives have agreed with the new legal settlement, but they claim the new measure could have repercussions on the national security. Some of these training programs represent highly important procedures that cannot be in any way neglected. By preventing the US Navy to carry out these exercises, the country may become vulnerable to underwater attacks, officials have concluded.
The legal settlement, which was approved by a Hawaii-based U.S. court, became effective on Monday. Greenpeace, the National Resources Defense Council and Earthjustice are some of the environmental group that have taken part in the legal action.
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