Dec. 29 (Bloomberg) -- The U.S. Navy settled a lawsuit brought by environmentalists and agreed to continue research on how the Navy’s use of sonar affects whales and other marine mammals, the Associated Press reported.

Sailors would not be required to adopt extra measures to protect the animals when sonar is used, according to the settlement, AP said.

Plaintiffs including the Natural Resources Defense Council had asked the judge to dismiss the case Dec. 26, AP reported. The lawsuit sought restrictions on mid-frequency sonar the Navy uses to detect enemy submarines, charging that it disturbs and sometimes kills whales and dolphins, according to AP.

To contact the reporter on this story: Nadine Elsibai in Washington at nelsibai@bloomberg.net

Last Updated: December 29, 2008 07:51 EST