That's a shame you were treated so poorly but maybe its this guys normal demeanour and nothing you did wrong.
The Crown Land Atlas is pretty good and much more up to date than some of the old paper editions of the Crown lands that used to be available. Hopefully some of the other members who do duck hunt in your area will help out. Don't get discouraged, geese do a fair amount of damage to land owners properties so hopefully you will meet someone that wants a few taken out.
If your door knocking at farms just be aware of the times you knock and the days. These folks are pretty busy so just bear that in mind and I would not show up dressed as a hunter for the initial door knocks.