They eat a lot. The migration process is slow, and often takes several months for geese, so they need to eat about the same as they normally would. They can dig through snow covered fields to get to grass, corn, and quite possibly their favorite – winter wheat. If snow is too deep to get through, they may keep flying in search of more accessible food. If they do find a good area with easily accessible food, they may stay there for a few days to load up before making the next leg of their trip.