Why are the geese on the move so early?

This movie was taken at 8 pm and every night around this time the geese are on the move from the fields back to their night camp. During this time of year the many fields of peas and beans are being harvested by the mechanical harvesters. These machines leave or spill a fair amount of peas etc on the ground. It seems these geese know all about it and are happy to clean up the residue. They come from all around to enjoy the feast.

In the morning they fly back to their favourite field for more goodies......getting a good fat build up for the winter.