Duck Migration Powers Up

Cold temperatures, snow and wind this week across the Dakotas and Minnesota are being watched closely by Iowa waterfowlers. Migrating duck numbers have gradually been increasing in Iowa. This week’s weather will push lot of those northern birds south. That is good news here for hunters, birdwatchers and other outdoor enthusiasts IF the ducks and geese stick around.

It’s important to look at the whole weather system, not just which way the wind is blowing, where--and on the days--you hunt.

“A lot of ducks are moving south, but how the weather system tracks is important,” reminds DNR waterfowl technician Al Hancock. “If we are sitting with west winds blowing out of the Dakotas and through Iowa, that’s optimal.”

However, he reminds hunters that it is important to look at the rotation of that storm cell; to track wind direction on the backside. If prevailing winds turn out of the southeast or south, it could set migrating ducks down for a couple days. If the north or westerly push continues, they could fly straight through. Most internet weather sites now have wind maps available. 

“We had a gradual increase in numbers through the third week of October; no major movements,” said Hancock. “However in the last two weeks, we have seen bigger migration.” 

He charts weekly counts, reported from refuges, hunting areas and other wetland locations across Iowa. The weekly statewide waterfowl report is at www.iowadnr.gov. Click on Hunting, then Migratory Birds, to find your way to the reports…filed each Friday.

From his vantage point last week, in the center of the Hawkeye Wildlife Area refuge, on the Iowa River corridor, one of those reporting DNR workers--wildlife biologist Tim Thompson--could see the number had climbed. 

“I’m seeing more ducks coming in than going out. Our count is over 14,000 total; up from about 5,500 the week prior,” noted Thompson. “We have more mallards and green-winged teal; not as many pintail as earlier. We are picking up a few of the later migrants; a handful of common mergansers, some bufflehead. There is still plenty of season remaining, though.”

On the Hawkeye area, Japanese millet and winter wheat, seeded in late summer, provide better fuel for their trip south than the smartweed, aptly named duckweed and other natural vegetation. That can hold waterfowl longer; so long as the weather is not warning them to keep pushing south.

Last week’s counts tallied at 72 statewide refuges and other wetlands went from 62,800 to 119,000, just days before strong north and west winds were expected to blow four to six inches of snow into the Dakotas and Minnesota. The counts can change dramatically from day to day; depending on how many arrive and how many ‘short timers’ are pushed out.

Statewide, the counts—over the long term--provide a look at migration patterns; basically what comes through, when and for how long. That helps with season setting and better management of wildlife areas for the waterfowl.

“For the short term, they offer an impression of what was using the area during the week,” says Hancock. “When ducks decide to leave an area; that is the Great Unknown.”

He emphasizes that studying the weather charts, helps provide better decisions.

Iowa’s duck season, north of Highway 30, extends through December 7. South of 30, it continues through December 11. In the Missouri River zone, closing day is December 18.