I found this on the ND fish and game website:
"19. Nontoxic Shot Regulations
The possession or use of shot other than federally approved nontoxic shot is prohibited while hunting ducks, geese, sandhill cranes, tundra swans, mergansers, snipe and coot statewide. For a list of approved nontoxic shot, visit
http://www.fws.gov/hunting/whatres.html.
Nontoxic shot is required for all hunting on all U.S. Fish and Wildlife Service lands, including federal refuges and waterfowl production areas. This regulation applies to all hunters using shotguns, except while hunting turkeys and big game. These shot requirements are in addition to current statewide nontoxic shot requirements for migratory birds as listed above."
So, Yes...you need to use nontoxic shot. I would also make sure that your guns are plugged as well.
Good luck!