They do not stay in MN over winter A small amount of hardy mallards, Golden eye and Canada’s brave the winters in n MN. Some necks bread here but most use it as a stop on their migration. They fatten up on the wild rice crops and fresh water shrimp. Rice lake national wild life refuge holds 100’s of thousands to over a million each fall and a majority are ringers although I think the refuge counts are a bit inflated. I’ve been fortunate to see a few massive migrations of 50k+ birds that staged up and left all at once. Two of those were neck migrations. The roar of wings could be heard from a couple miles away. The sounds of jets when they’re bombing in out of the heavens will never get old. When you get in to the right spot they can put on the show.