The Federal Duck Stamp, aka the Migratory Bird Hunting and Conservation Stamp, program is recognized as a good investment in the effort to conserve wildlife habitat.
Ninety-eight cents of every duck stamp dollar goes directly into the Migratory Bird Conservation Fund to purchase or lease wetlands and wildlife habitat for inclusion in the National Wildlife Refuge System. This ensures there will be land for wildlife and humans that will be protected for generations to come.
These stamps are required purchase for waterfowl hunters, but this program is also supported by other people who recognize the value in protecting wetlands. There are several ways to purchase these stamps. Using this link, also supports Partners in Flight.