The waterfowl (geese and ducks) are hearty species, however many have traveled long distances and are stressed, hungry and weakened from the long flight some thousands of miles. They are programmed to migrate south just below the ice line in the winter months, for thousands of years. Maybe tens of thousands. In recent years, the winters are getting more intense over the past years. Even record breaking, despite the general belief of climate warming. Looks more like significant climate change.