Waterfowl hunters began buying them nearly a century ago. Just after that, collectors joined the fun.
Since its inception in 1934 when Franklin D. Roosevelt signed the Migratory Bird Hunting and Conservation Stamp Act into law, the duck stamp (as it’s commonly known) has garnered more than $1 billion for habitat conservation in the national wildlife refuge system.
Great Lakes Now
https://www.greatlakesnow.org/2021/04/duck-stamp-impacts-great-lakes-nationwide-refuge/