When you have millions of birds it's not that hard to follow them. Most years they have the exact same flight path. Example: Northwest Missouri (staging area) to the rainwater basin of Nebraska (water and food), to the Yankton area (food and water), to Aberdeen and on up north. How fast they move depends on the "snowline". They follow the melting snow and they must have open water. The old birds know the flight path and lead, juveniles follow later. Snow or storms will push them back south as happened this year. The guy I went with this year had 12 guides with numerous fields. We were locate in South Dakota. I think that he was there for 3 weeks before the birds slowed to nothing. 3-4 guys that follow birds

.. there are so many outfitters that it aint funny
If you want to make it even easier.... the are snow goose facebook pages. People tell you everyday where the geese are and how many are to bee seen. Technology
good luck to all
the dog