617 Texas horned lizards were released into the wild at Mason Mountain Wildlife Management Area. The Fort Worth Zoo has just released hundreds of Texas horned lizards back into the wild. This successful breeding program is aimed at seeing the indigenous lizard rebound ― bringing it back from the brink. This collaboration with partner institutions including Dallas Zoo, Caldwell Zoo, Fossil Rim Wildlife Center, and Pearland Nature Center, is yet another major conservation success for Fort Worth’s crown jewel, and one of the top zoos in the nation.