At least one and maybe two pairs of whooping cranes are now spending the winters in South Carolina's ACE Basin. The whoopers are part of a reintroduced flock that migrates between Wisconsin and the Southeast. The flock was raised in captivity and taught to migrate by following ultralight planes. They seem to be developing minds of their own now. This past year the southbound group following the ultralight to Florida refused to go beyond Alabama. And the SC birds have been coming here on their own for several years now. The highly endangered birds are North America's rarest and largest, standing 5 feet tall.