With time running out in this year's state legislative session, environmental lobbyists were nervously watching a proposal Wednesday they said invites challenges to Florida's manatee protection laws.

The plan would compel the Florida Fish and Wildlife Conservation Commission to maximize both manatee protection and recreational use of the state's waterways -- goals the environmentalists find contradictory.

The Senate version (SB 540) passed 32-7 Tuesday, while a nearly identical House version (HB 633) awaited a vote Wednesday night.

Environmentalists said the bills would set the stage for challenges by boaters to protections for the endangered sea cows.

"Say I was going 25 or 35 miles per hour in a manatee zone, and got a ticket. I can protest to the judge that the ticket is unlawful because it infringes on my ability to have maximum use of the state's waterways," said Pat Rose, a biologist and lobbyist with the Save the Manatee Club.

Rose said environmentalists would push for a veto from the governor if the bill passes the House.

Gov. Jeb Bush's staff, Rose said, has already indicated to him they had "problems" with the legislation. But a governor's spokeswoman said Wednesday no decision had been made.

Proponents say the bills merely seek a balance between manatee protections and boaters' rights.

But environmentalists have long viewed the bill, which was written in part by boating industry lobbyists, as a laundry list of threats to existing manatee protections.

The original version called for definite figures for ideal manatee populations by region, and made it harder to enact new boating restrictions in regions meeting those goals. As amended in the Senate, the bill allows the government more discretion in creating restrictions.

The bill also calls for studies into the effectiveness of boat speed signs and to determine whether manatees are subject to disease when congregated around power plants, and whether they destroy submerged seagrasses.

Critics say the agenda behind the seagrass and disease studies is to show Florida's manatee population as too large for its food source, prone to disease, and ultimately in need of management.

It's essentially a game approach, said Florida Audubon's Eric Draper. "With game animals, you look for target reproductive populations and allow anything above that to be killed -- that's OK for deer but not a good endangered species management policy. We want an abundance of manatees."

But Wade Hopping, a lobbyist for the National Marine Manufacturers' Association, argued there was no hidden agenda behind the studies.

The scientists commissioned "will do the study any way they damn well please," he said, and won't be influenced by politics.