WASHINGTON — The Senate unanimously approved a bill to revamp management of the nation's marine fisheries and strengthen protections against overfishing of dwindling stocks.

The bill requires the use of annual catch limits and enhances the authority of eight regional fishery-management councils, as Congress struggles to protect vulnerable fish stocks while keeping struggling fishing industries afloat.

The bill reauthorizes the Magnuson-Stevens Fishery Conservation and Management Act, the 30-year-old law that oversees fishery management in waters between three miles and 200 miles offshore. The House is considering a different version of the bill.

Sen. Ted Stevens, R-Alaska, who led efforts to update the bill that bears his name, called it critical legislation that should "ensure the productivity and sustainability of our nation's fishery resources."

The bill also would bolster the role of scientific advisory committees and incorporate several recommendations from the U.S. Commission on Ocean Policy, which has called for an overhaul of U.S. ocean policies and laws.

Lee Crockett, executive director of the Marine Fish Conservation Network, an advocacy group, called the bill a step forward.

"Most importantly, this bill does not roll back existing conservation measures already in place, unlike its counterpart in the House which almost ensures that fish populations will continue to decline," Crockett said.

The House Resources Committee approved a bill last month with language that critics say could allow continued overfishing of depleted stocks.

Passage of the Senate bill was delayed for nearly two weeks by West Coast senators seeking financial assistance for salmon fishermen hurt by a sharply curtailed season.

Democratic Sens. Ron Wyden of Oregon and Barbara Boxer of California dropped their opposition after Senate leaders agreed to make West Coast salmon fishermen eligible for disaster assistance.