The famous King Ranch down here in south Texas first releashed Nailgi along its coastal praires back in the 30's I believe. From what I understand the King Ranch got some of its original animals from the San Diego zoo many years ago. The ranch started off with 11 animals, the population is now estimated at well over 10,000 animals that have spread their ranges over 5 different counties (although the king ranch has land in each of these counties).