1. Department of Range, Wildlife and Fisheries Management and Texas Cooperative Fish and Wildlife Research UnitTexas Tech UniversityLubbockTexas79409‐2125USA
2. Department of Physiology, Faculty of Veterinary MedicineMenofyia UniversitySadat City MenofyiaEgypt
3. Texas Parks and Wildlife Inland FisheriesHeart of the Hills Research StationIngramTexas78025USA
4. U.S. Geological Survey, Texas Cooperative Fish and Wildlife Research Unit, and Departments of Biological Sciences and of Range, Wildlife and Fisheries ManagementTexas Tech UniversityLubbockTexas79409‐2120USA