In this case they may eat anytime of the day or night. Ducks do feed every day. Just because you don't see any where you are, don't assume there are none in the area. Move and keep moving until you find them Ducks fly lower and move around more on cloudy, windy days. Warm, still sunny days are usually poor days for hunting, except during peak periods of migration.
Ducks migrate by the calendar as much as by the weather.
Early to late freeze-ups may affect the migration, but the major movement of each species will usually come within the same week or ten day period. Some ducks are smarter than others. Teal and wood ducks are considered among the less wary. Of the diving ducks, greater scaup, canvassbacks, ringbills, and goldeneyes are harder to deceive, while redheads and lesser scaup decoy more easily. In 1990, overshooting by market hunters had reduced the continental population of greater snow geese to fewer than 3,000 birds.