This 5-cent U.S. postage stamp commemorates the 50th anniversary of the 1916 Migratory Bird Treaty between the United States and Canada. Issued in 1966, the stamp features stylized outlines of two birds in flight, one over a red field symbolizing Canada and the other over blue for the U.S., with a central map design illustrating cross-border migration. The treaty marked a landmark conservation effort to protect migratory birds from overhunting and habitat destruction. Its legacy continues to influence wildlife laws today.