"Late season is a little easier to understand because you're dealing with frozen conditions, snow cover and loss of food resources," says Humburg. "Earlier in the year it's not always quite as clear because habitat
and food are still quite good, but these birds are migrating on an initial, near-term cue from weather conditions."
Humburg says that an initial dip in temperatures at Ducks Unlimited's Goebel Ranch in north-central South Dakota
will send many of the blue-winged teal that nested or were hatched amid that sea of grass and wetlands south toward the Gulf of Mexico or to points even further south. Another cold snap will bring spur the migration of pintails, wood ducks, gadwall and widgeon.
For those hunters waiting on the arrival of these early migrants, Humburg says that the ducks' needs to replace fat reserves that were lost on migration should help pinpoint where to look for hunting opportunities.
"Early season migrants search out food resources like natural seeds, smart weed, and millet," says Humburg. "Teal will also move in to shallow, flooded agricultural fields looking for waste grain, second-crop rice, moist-soil seeds and certainly some invertebrates. Gadwall, widgeon, and pintails are going to be more in the open water, looking for submergent food sources more so than teal in the shallows."