1. U.S. Geological Survey Patuxent Wildlife Research Center 12100 Beech Forest Road Laurel Maryland 20708 USA
2. U.S. Fish and Wildlife Service 1201 Oakridge Drive Fort Collins Colorado 80525 USA
3. U.S. Fish and Wildlife Service 5275 Leesburg Pike Falls Church Virginia 22041 USA
4. U.S. Fish and Wildlife Service 2651 Coolidge Road East Lansing Michigan 48823 USA
5. Ducks Unlimited, Inc. 1 Waterfowl Way Memphis Tennessee 38120 USA
6. Ducks Unlimited, Inc. 363 NW 52 Road Clinton Missouri 64735 USA
7. Ducks Unlimited, Inc. 7322 Newman Boulevard Dexter Michigan 48130 USA