NOFOLK, Va. — The Navy says its preferred location for a proposed sonar range to train submarine hunters is in Florida waters instead of off Virginia or the Carolinas.

The Navy says the 625-square-mile site off Jacksonville, Fla., is outside an area of the Atlantic frequented by endangered right whales, The Virginian-Pilot of Norfolk reported Monday. But environmental groups contend the sonar still can harm the whales, which use sounds to communicate and are sensitive to sonar.

Hearings on the plan are scheduled to start this week. The first hearing is Monday at Chincoteague, near the Virginia proposed site.

A North Carolina hearing is scheduled Wednesday at Morehead City, N.C., and two more hearings are scheduled early next week in South Carolina and Florida.

More than 40,000 pages of comment from the public already have been filed with the Navy on its plan and much of the comment is critical.

Duke University environmental law professor Michelle Nowlin said the Navy could be in conflict with state and federal government work to protect the whales.

The newspaper said experts think less than 400 right whales still live in the north Atlantic. Pregnant females migrate in winter to warm waters off Florida and Georgia to have their calves.

A Navy official said the habitat for the whales extends about 20 miles off the north Florida coast while the closest boundary for the sonar range is 50 miles offshore.

"We believe we're far enough off that we're not going to have an adverse effect on right whales," said Jene Nissen, environmental acoustics manager for the Navy's Fleet Forces Command.

Nissen said any effects from sonar pulses on whales would be low level and not permanent.

The Navy has said it needs the range, which is an array of underwater microphones to detect sonar, so sailors can train on detecting quiet diesel subs in noisy nearshore waters.

Navy officials said the range would cost about $100 million and be used for periods up to six hours about 480 times a year.

One favorable point for the Navy's plan is that its fleet of sub-detecting planes and helicopters are being based in Jacksonville.

Spokeswoman Marguerite Jordan of Florida's Department of Environmental Protection said her agency is reviewing the Navy's analysis. The state's Fish & Wildlife Conservation Commission already has told the Navy it shouldn't consider locating the range offshore or not use it between mid-October and mid-April when the whales are giving birth to their young.

North Carolina officials aren't sure the state is out of consideration. It is the third alternative, behind the waters off Charleston, S.C.