In the late season, duck hunters should tailor their calling to specific scenarios, such as large flocks, pairs, or singles. Large flocks signal a mass movement of "new ducks" up or down the flyway, and this is when hunters should call persuasively in terms of volume and frequency. This is a good time for two callers to work together to draw big flocks to the spread. Aggressive calling can also be effective on single birds late in the season.
In shrub/scrub habitat, however, paired ducks are not really focused on other birds, and as a result, they are not very vocal. It's usually better to tone down your calling in these areas, relying heavily on chatter and single-hen quacks rather than more aggressive calls.
Set a realistic decoy spread
Like calling, late-season decoy spreads should be tailored to different hunting situations. In fields and open areas, hunters should set large spreads with more drakes than hens. This provides a natural look for both migratory flocks and unpaired males.
In thick cover, spreads should be small, and hen-and-drake pairs should be scattered broadly with plenty of room between the pairs. A wide landing area should be left in front of the blind, since ducks may be reluctant to land close to other decoys. And in this situation especially, decoys should be clean with bright colors to show mating plumage of the drakes.
Also, in the shrub/scrub environment, hunters should employ some means for decoy movement—a jerk string, a swimming decoy, kicking water, etc. Agitating the water's surface can be crucial to convincing wary ducks to come in.