We got up in the air for the 3rd waterfowl flight of 2024 on Monday, September 16. The rain from the Hurricane never quite made it here, so we’re still drying out mudflats and exposing more along the backwaters. We lost some blue wings since last week, especially in the Illinois River Valley (-26%), but seemed to have gained some green wings behind them. Regardless, blue-winged teal abundance remained above LTA (+43%) for the IRV (20,280), but 11% below LTA for the CMRV (3,395) this week. Total duck abundance (36,320) was 5% below the LTA for the Illinois River, and 37% below the LTA for the CMRV (5,460). It’s typical for total duck abundances to drop slightly this week as blue-winged teal migrate out of our area at a faster rate than other early migrators make their way here. However, the abundances of ducks not named BWTE are below LTA across all species for this week. And we seem to be holding “near-peak” numbers of BWTE a little longer than usual. This may be an artifact of the unseasonably warm weather the prairies and upper Midwest are experiencing right now. The 10-day forecast predicts a little temperature relief early next week. We’ll see if that holds true.
I wanted to switch gears and highlight some past research that I’ve been asked about by hunters. Forbes staff, led by Andrew Gilbert, recently published the wood duck work conducted during 2018-2020 in the Journal of Wildlife Management. We marked wood ducks with transmitters during late summer and tracked their movements to determine home range, departures, and survival. Wood ducks in our study area had greater daily movement distances in October and November as compared to August
and September, potentially due to hunting disturbance, increased food-searching, or general restlessness prior to migration. They predominantly used wooded and emergent wetlands during their stay here… wood ducks use the woods, no kidding?… (but also, cattail and lotus beds). The average departure date from our area was Oct 27, but adult males tended to leave 11-16 days before other sex/age cohorts. Our latest observed departure was December 15th. Survival? Not bad, coming in at ~80% across all age/sex cohorts. Interestingly, survival was positively related to increasing river levels.
Seemingly as the river put more water on the landscape, wood ducks could spread out to avoid hunters. An alternative way to view this result is that less water-concentrated wood ducks are in or near hunted areas.
Thanks to everyone who made this research possible. Too many to list, but you know who you are.
This week’s numbers and more info about us are on our Aerial Inventories page.
