From the Pheasants Forever member magazine
Duck Stamps are the primary funding source for the purchase of smaller natural wetlands and uplands which comprise Wildlife Protection Areas. There are over 26,000 WPAs in the U.S., located mostly in the prairie pothole regions of the Minnesota, the Dakotas, Montane, Michigan, Nebraska, Iowa, and Wisconsin. Learn more about the duck stamp at www.fws.gov/birds/get-involved/duck-stamp/php
The funded land, as you surely know, benefits are more non-game birds than those species hunted for sport.