Trans-Pecos Copperhead At Rattlers & Reptiles, A Small Museum In Fort Davis, Texas, Owned By Buzz Ross. Pictured Is A Trans-Pecos Copperhead At Rattlers & Reptiles, A Small Museum In Fort Davis Owned By Buzz Ross. The Trans-Pecos Copperhead, Agkistrodon Contortrix Pictigaster, Feeds On A Variety Of Small Rodents, Reptiles, Amphibians And Insects. It Reaches A Length Of Twenty To Thirty Inches.