1. US Fish and Wildlife Service – Division of Migratory Birds, Albuquerque, NM 87103 USA
2. Eagle Environmental, Inc., Santa Fe, NM 87508 USA
3. US Geological Survey Texas Cooperative Wildlife Research Unit, Texas Tech University, Lubbock, TX 79409 USA
4. US Fish and Wildlife Service – Division of Migratory Bird Management, Mountain Prairie Region, Denver, CO 80225 USA
5. Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409 USA