A federal judge yesterday ordered the U.S. Navy to adopt specific restrictions on its use of sonar in order to protect whales and other marine mammals off the California coast. Mid-frequency sonar has been accused of causing a wide range of problems when it’s used within proximity of marine mammals, such as temporary deafness, beachings, and various other injuries, including death. Among the restrictions the judge imposed are a 12-mile no-sonar buffer zone off the California coast, a prohibition on mid-frequency sonar use when marine mammals are within 2,200 yards, and stipulations that the Navy must train and post people to look for the animals before and during sonar exercises. The judge also said the Navy must look for marine mammals for one hour before commencing mid-frequency sonar use. The ruling called the Navy’s proposed plan of shutting off the sonar when marine mammals come within 200 yards, “grossly inadequate to protect marine mammals from debilitation levels of sonar exposure.”