The amount of money raised by the federal duck stamp program since its introduction in 1934. That money has been used to protect more than 6 million acres of waterfowl habitat. Congress this month approved raising the cost of a federal duck stamp from $15 to $25. The last time the price of the duck stamp was raised was in 1991. A statement from the U.S. Fish and Wildlife Service said the increase will enable the agency to protect some 17,000 additional acres of waterfowl habitat every year.