http://ndow.org/hunt/seasons/upland/2011_12/2011_12_Upland_web.pdf
"Hunting on Wildlife Management Areas
Non-toxic shot must be used for all species
when hunting on Wildlife Management Areas (NAC
503.183).
The use or possession of shells for a shotgun
containing shot that is toxic, or larger than
standard-sized T is prohibited on the Overton,
Key Pittman, W.E. Kirch, Scripps, Mason Valley,
Fernley, Alkali Lake, Humboldt, Steptoe Valley and
Franklin Lake Wildlife Management Areas (NAC
504.135).
The use of shotguns capable of holding
more than three shells is prohibited on all wildlife
management areas unless it has been plugged
with a one-piece filler, incapable of removal without
disassembling the gun, so its total capacity does
not exceed three shells. (NAC 504.135)"
This is a really strange law, as you can make custom short loads of say 2" and load up with 4 shots.