With Florida's manatees dying in record numbers, groups are trying to save them

Nearly every morning at Florida's Blue Spring State Park, Cora Berchem hand counts the manatees that flock there in the winter for the warm water.

"We've had days in here where we had over 600 manatees," Berchem, who works for the nonprofit Save the Manatee, told CBS News environmental correspondent Ben Tracy.

She knows most by name because of their distinctive scars from being hit by boat propellers.