Ducks know they have to migrate because ice in more northern climes will eventually cover and kill all food sources. But it s not the cold itself that forces the ducks to leave. In fact, there s no ice anywhere to be found when several species, like blue-winged teal, pintail and gadwall, leave the northland. They re migrating early to sort of beat the rush to the food. Ducks migrate back north in the spring because they don t like the heat of Southern summers.
Ducks are quite content in Louisiana s balmy heat.
There are at least two reasons ducks head back north after winter. There are hardly any birds that are ground-nesters in the South. The second reason ducks nest in the northland is that the sun is shining for a much larger percentage of the day in the North during the summer than it is in the South. Ducks use this daylight to feed almost around the clock. Up in the Arctic, where the sun shines 24 hours a day, geese feed continuously, he said.