Cold-weather ducks

We waited until Wednesday of this week (December 2nd) to fly the waterfowl survey. The weather looked good so we decided to see what the cold snap would do to duck numbers. I feared most of the ducks would get out of here with the 20ºF low temps on Monday and Tuesday. Boy was I wrong! We had lots of ice on Wednesday morning, but the ducks stayed. In fact, we saw more ducks than before Thanksgiving along both rivers. I am sure we had some new ducks arrive with the cold weather and north winds, as evidenced by the increasing number of mallards and common goldeneye (commonly known as whistlers or ice ducks). And we had some other divers (primarily lesser scaup) take off for warmer climates. The departure of scaup was also apparent in our band return data from ducks that we leg band during spring around Havana, IL and Pool 19 of the Mississippi River. Our weekly band return report from the Bird Banding Lab indicated the lesser scaup are definitely in Louisiana and Texas with several bands being reported from the deep south.

This week we observed ~423,000 ducks along the Illinois River and ~830,000 ducks on the central Mississippi River. These numbers are well above average for the first week of December and 7% greater than last week along the Illinois River and 25% more than last week on the central Mississippi. Once again mallards were the most numerous species with almost a half a million mallards along the central Mississippi River and well over a quarter million on the Illinois River. I know many duck hunters in Illinois are going to doubt those numbers because hunting success has been poor for the most part, but we took several photos to show how they hunkered down and kept pockets of water from freezing in the cool temps. I guess we will see next week when we warm up and thaw if the ducks continued to stick around.

Be careful in the cold and ice!

Ducks using an open water area on one of the frozen refuges on December 2nd, 2020.
A dense flock of mallards.
More mallards from the central Mississippi River.
Can you pick out the northern pintail and green-winged teal among these mallards?

Illinois River Waterfowl Aerial Inventory – 12/2/2020

Central Mississippi Waterfowl Aerial Inventory – 12/2/2020