1. The Wildlife Toxicology Laboratory, The Institute of Environmental and Human Health, Texas Tech University, Box 41163, Lubbock, Texas 79409, USA
2. Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, 700 University Blvd., Kingsville, Texas 78363, USA
3. Texas AgriLife Research, Texas A&M University System, San Angelo, Texas 76901, USA