Florida wildlife officials say they\'re about to outlaw the killing of tiger sharks and three kinds of hammerheads that prowl the state\'s waters. The new rule, to be voted on by the Florida Fish and Wildlife Conservation Commission, would add four new species -- tiger sharks as well as scalloped, smooth and great hammerheads -- to 23 sharks already protected from harvest in Florida waters, which extend three miles off the Atlantic coast and nine miles off the Gulf coast, the South Florida Sun Sentinel reported Tuesday. Catch-and-release fishing would still be allowed. Shark experts and environmentalists have lauded the Florida proposal, noting populations of all four species have declined by more than half in recent decades. The hope, they say, is Florida\'s action, the first in the nation, will clear the way for extending protections in both federal and international waters. \"It\'s a big step but we\'re going to need the federal government to step up and do their part as well,\" said Neil Hammerschlag, a professor and shark expert at the University of Miami.