Two species of sawfish which were once widespread in U.S. waters could be wiped out completely if the BP oil blowout reaches the Gulf loop current, warn scientists. Proposals are in place to make both species the only two marine fish in U.S. waters to receive federal protection as endangered species, reports ScienceDaily.

While the smalltooth sawfish has already enjoyed such protections since 2003, its close relative, the largetooth sawfish, has remained unprotected by the Endangered Species Act, despite not being seen in U.S. waters since 1961. If any largetooth populations still exist along the Gulf Coast, scientists fear that the oil spill will wipe them out.

Meanwhile, the only remaining smalltooth sawfish populations are found along the lower peninsula of Florida. Many of those animals have their nurseries confined to a region now threatened by the oil spill.

"As oil gets caught up in the Loop Current, it will be pulled down into the Gulf Stream, which goes right by Key West on its way up the U.S. East Coast," said George Burgess, a University of Florida sawfish expert. "The opportunities for serious ecological problems are mind-boggling, with dire implications for what's left of that species in the northwest Atlantic Ocean if the oil reaches critical mangrove habitat."

Sawfish are unusual fish with some of nature's most intimidating snouts. As their namesake suggests, the snout, or rostrum, is shaped like a saw and lined with sharp teeth, which the animal will slash ferociously at prey that swims by. Although they look like sharks, they are actually in a family all their own and are most closely related to rays.

One reason sawfish are particularly vulnerable is that they have a relatively slow growth rate and a delayed onset of sexual maturity. "Our recovery plan [for the sawfish] covers 100 years, which should give a pretty good indication of how much trouble the animal is in," noted Burgess. That was the recovery plan before the oil spill.

"If important underwater habitat is destroyed, neither species will have a place to return to," he said. "They can't come back to an underwater desert."

Bryan Nelson ( @@brynelson ) writes about everything from environmental problems here on Earth to big questions in space.

Sawfish may go extinct in U.S. due to Gulf oil spill
These iconic fish with toothy, saw-like snouts are likely to have their remaining habitat within U.S. waters engulfed by oil.