More mallards, fewer northern pintail and northern shovelers

We completed the aerial waterfowl inventory of both rivers on Wednesday, October 28th. It seems like it has been a while since the weather has cooperated with us. I need to send out a Big Thanks again this week to Josh Osborn for taking my seat in the airplane. Today is my last day in Covid-19 quarantine, so hopefully, I will be back in the air next week. Josh estimated over 271,000 ducks in the Illinois River Valley (IRV). This estimate is about 3% below the 10-yr average, but up 32% from last week. We lost some of the early season migrants, like northern pintail and northern shoveler, but picked up some mallards, which were 26% above average and nearly double what we had last week in the IRV. The central Mississippi River Valley (CMRV) had over 252,000 ducks about 35% above average for the last week of October. It was hard to make comparisons between weeks because we missed the lower portion of the CMRV due to low clouds last week. However, I think we had a push of new birds into the central Mississippi River because a few diving ducks trickled in on Pool 19 and Port Louisa and Henderson Creek duck numbers jumped substantially. I have heard many reports of quality duck hunting over the past week, including Granite City, Nutwood, Pleasant Hill, Beardstown, Havana, Manito, Chillicothe, and Hennepin. Let’s hope the trend continues!

I decided to post some graphs representing the weekly averages (2010–2019) of duck species along the two rivers. The averages are one way to gauge how the migration is progressing each week. By looking at the graphs, one can see how migration chronology varies by species. Several species, like pintail and gadwall, have reached their peak numbers in central Illinois by early November; however, the coveted mallards and canvasbacks peak much later and maintain those numbers for multiple weeks during fall. If you are chasing pintails, you better get after them because by Thanksgiving many will be gone.

Good luck and stay safe!

Illinois River Waterfowl Aerial Inventory – 10/28/2020

Central Mississippi Waterfowl Aerial Inventory – 10/28/2020

Photo credit: Ryan Askren
Average duck abundance in Illinois River, 2020

Wind, Rain, & Fog

It has been a rough two weeks trying to get the waterfowl surveys completed. If you remember, the week of October 12th, the wind blew with gusts to 45 MPH all week, and this week (October 19th) we had wind, rain, fog, and low ceilings. Those weather conditions aren’t conducive to flying VFR (visual flight rules) surveys. To add to the frustration, I was out of commission this week and my colleague, Josh Osborn, had to step in and fly the surveys. Josh and Mike were able to complete the Illinois River Valley (IRV) and partially finished the central Mississippi River Valley (CMRV) flight on Wednesday, October 21st, 2020. We failed to obtain waterfowl abundance on the lower CMRV from Clarence Cannon refuge to the confluence with the Illinois River. I did speak with some duck club managers in the confluence region, and they indicated good numbers of ducks down there with recent arrivals. With that, total duck numbers (205,140) were up 24% in the IRV from last week and were very close to the 10-yr average of 215,777 ducks. Josh noted that nearly every surveyed location had increased duck numbers this week, compared to last week. A random assortment of nearly all the monitored species of ducks and geese were present this week, including a smattering of diving ducks in a few locations.

I wanted to plug our research project on wood ducks again this year. The Forbes Biological Station has ~100 wood ducks marked this fall. This study is part of a 3-yr project to evaluate postbreeding wood ducks in the IRV. We captured wood ducks near Banner, Havana, and Chandlerville this year and deployed 33 GSM cellular transmitters and 70 VHF transmitters. The birds are currently scattered between Pekin and Beardstown along the Illinois River and in streams, ditches, and ponds several miles from the river floodplain. I would expect a few of the birds to depart central Illinois with the cooler weather that is arriving and the start of the Illinois central zone ducks season opener on October 24th. If you happen to harvest one of these ducks, please give us a call so we can add the information to our database. Our office number is 217-332-3825(DUCK); however, most of our staff are working remotely from home due to Covid-19. You can also email me at with your harvest, and we will do our best to give you a brief history of the birds movements since August. The harvested transmitter is yours to keep, we just want the information about the bird. Of course, PLEASE report your leg bands to

Good Luck to those of you heading to the duck blind this weekend for the central zone waterfowl opener!

Illinois River Waterfowl Aerial Inventory – 10/21/2020

Central Mississippi Waterfowl Aerial Inventory – 10/21/2020

Drake wood duck with bib-mounted VHF transmitter.
Hen wood duck with a GSM cellular transmitter. Photo credit to Ryan Askren.
Hen wood duck with a GSM cellular transmitter. Photo credit to Ryan Askren.

Teal numbers lower this week

After the rain and weather kept us grounded last week, we got back at it on Wednesday, September 16th. Blue-winged teal (Spatula discors) numbers dropped this week from what we witnessed on September 2nd; however, this wasn’t a big surprise. The teal migration was a little early this year with the weather patterns we have been witnessing. BWTE usually start with a bang in early September and decline rapidly from there. Green-winged teal (GWTE; Anas crecca) start slow and peak in late October/early November (Fig. 1). I expect the BWTE numbers to be even lower next week as the temperatures are forecast to dip into the lower 40’s over the weekend. Teal abundance this week was 30,895 and was down 32% from the September 2nd numbers along the Illinois River. This week we were closer (+9%) to the 10-yr average of 28,417 for teal. We also estimated 7,685 teal along the central Mississippi River, which was up 24% from the 10-yr average but down 23% from earlier in the month. Water was scarce at several of the top refuges of the lower Mississippi this week from Quincy to Grafton. This water management practice is usual as they gear up for October arrivals.

I saw a Facebook post from a friend today that caught my eye. Pat Gregory hunts near the Forbes Biological Station and is usually successful at harvesting a few of the “blue rockets” storm trooping his decoys. Pat loves to hunt over wooden decoys, as he is a passionate decoy carver himself. A tradition that was handed down from his grandfather I believe. Anyway, Pat snapped this photo of the morning’s bounty. He informs me the decoys were carved by Tyler Wood, and they were obviously good enough to lure this individual within range. Thanks for sharing Pat!

Be safe out there and enjoy the last weekend of teal season.

Illinois River Waterfowl Aerial Inventory – 9/16/2020

Central Mississippi Waterfowl Aerial Inventory – 9/16/2020

blue winged teal with 2 wooden decoys
Successful harvest of a blue-winged teal (Spatula discors) using handmade wooden decoys along the mudflats of the Illinois River. Photo by Pat Gregory and decoys carved by Tyler Wood.
Migration chronology of teal along the Illinois river. Weekly numbers represent the 10-year average (2010–2019).
Migration chronology of teal along the central Mississippi river. Weekly numbers represent the 10-year average (2010–2019).

Back in the air

We’re back in the air again. Actually, we’ve been at it for a month now counting shorebirds, but we completed the 1st teal flight of the year on Wednesday, September 2nd. There was an abundance of blue-winged teal (Spatula discors) along both rivers for the first week of September. We estimated 45,240 blue-wings along the Illinois River Valley (IRV), coming in at 139% above the 10-yr average. The central Mississippi River also had good numbers of blue-wings totaling 9,910 birds, 127% above average for the first week of September. Blue-wing numbers in the IRV were actually quite staggering. The 45,000+ birds witnessed this week was the 9th highest total in 72 years of surveys and will be the 5th highest peak count of blue-winged teal since 1948. Hopefully we will enjoy a great opening day of teal season beginning Saturday, September 5th.

Illinois River Waterfowl Aerial Inventory – 9/2/2020

Central Mississippi Waterfowl Aerial Inventory – 9/2/2020

scattered blue-winged teal in wetlands
Blue-winged teal (Spatula discors) prefer the very shallow water and sloppy mud usually found along the perimeter of wetlands.
Southwesterly view of Chautauqua NWR on September 2, 2020.
Northerly view of the Cuba Island complex at the Sanganois State Fish and Wildlife Area near Chandlerville, Illinois. The Cuba Island complex is a mix of public and private wetlands. The bottom portion of the photo is known as the Barkhausen Refuge. The central portion is called Otter Lake, while the northern end is Mound Lake. In the distance, you can see Crane Lake in the top left portion of the photo.





March 4th aerial survey

Upper Illinois River

Turner Lake 1009000000000000000000010000000000
Depue, Spring 1009000000000000000030030000000300
Coleman Lake 100900000000000000004004012000002000
Bureau Ponds 100100000000000000000000000000000
Goose Lake 100900000000000000100030004000500020010
Senachwine Lake 100700000000010010000300100150000000000
Hennepin/Hopper 100905000000000000010015002102035000000010
Swan Lake 1001000000000000000000001000001000
Sawmill Lake 1009000000000100500000015000003700
Billsbach Lake 10070000000001000200000000300000000000
Weis Lake 100100000000000000000000000000000
Sparland 1009000000000001000000100110000001000
Wightman Lake 1008000000000000000015015000000000
Sawyer Slough 100901300000000001000100100025060010000000100
Hitchcock Slough 10090100000000000000010001106000000000
Babbs Slough 100900000000030020000100002401000000000
Meadow Lake 100900000000000000002000200000001000
Douglas Lake 1009025000000000510013000010002000461030015000000100
Goose Lake 1009020000000030001600000010502025000000000
Upper Peoria 1007020000000031200110001008100320054703000003300
Lower Peoria 100900000000010000000001019000000100
Total Upper Illinois273000000004090046150100107001580014185144028550001316020

Lower Illinois River

Pekin Lake 100100000000000000000000000000100
Powerton Lake 10001000000010000000000405060551000001000
Spring Lake 1009020000000000000100019301020604604000500000325
Spring Lake Bottoms 100100100000045000000000055000000000
Goose Lake 1008050000000360001650000013005385000000000
Rice Lake 10090000000000000000100010010000000000
Big Lake 1009000000000200200020025085302000001000
Banner Marsh 9090000000000000010015051654052000000000105
Duck Creek 1003048100000030001000001000510057301550232002030000000135
Clear Lake 100900000000010001002000000040041000000000
Chautauqua 100805000000002000001002200110068031020005001100
Quiver Creek 1009014000000030005002000000001950780101005002000
Quiver Lake 1008000000000000000000010050000100
Emiquon/Spoon Btm 70908600000000250001000250031502250515074026001400000018190510
Matanza Lake 1009000000000000002000200220110500000000100
Bath Lake 100900000000000000100100011025100000000
Moscow Lake 1009010000000001000000200000400000000000
Jack Lake 10090000000000000000000000000100
Grass Lake 1009000000000300003000020000035002002000000000
Anderson Lake 100900000000000000001000100200720026000000000
Snicarte Slough 10090000000000030000150000450000000000
Ingram Lake 10090000000000000000000000000000
Chain Lake 1008000000000130020080000100010024101000000000
Stewart Lake 1009000000000100000015000115000000000
Crane Lake 100501000000003002000032001600720000000000
Cuba Island 1009030000000000500500100010000000510080043001000200950
Sanganois 100902000000000500010500000300020502000000220115
Treadway Lake 1009000000000100120080000001000220010000000000
Muscooten Bay 100100000000000000000000000000000
Big Lake 100900000002000500010001000000900000000000
Meredosia Lake 100705300000000020000265000300011100113602002003100001100
Smith Lake 10090500000000050010000002056754402000000000
Spunky Bottoms 100905000000000000001000006007201000200007105
Total Lower Illinois 1686500000945014660190010270550200236005505205327578955781518962500352702245

Upper Mississippi River

Muscatine - Moline 10090000000000000025500300028501005000010200
Andalusia Refuge 100100000000000000000000000000000
Louisa - Muscatine 100500000000000000149009350242522503000006400
Louisa Refuge 100100000000000000000000000000000
New Boston 10090000000000000000200020060015000001200
Keithsburg Refuge 100100000000000000000000000501000
Oquawka - Keithsburg 100700000000000000500145019521000005000
Henderson Creek 100900000000000000003200320000002100
Oquawka Refuge 100100000000000000000000000000000
Crystal Lake 10090000000000000000000502500000005
Burlington - Oquawka 10040100000000000000900025001250900450010002205
Dallas City - Burlington 1006010000000000011000305035008652102005010000911015
Turkey Slough 100100000000000000000000000000000
Fort Madison - Dallas City 10090000000002000100005002000550070403000000000
Nauvoo - Ft. Madison 100900000000017000600010019000400047004802200003000
Arthur Refuge 100100000000000000000000000000000
Keokuk - Nauvoo 1009000000000230001500085002000350021000000000
Total Upper Mississippi 20000000004200096001008095033000168555915338603110503922025

Lower Mississippi River

Meyer - Keokuk 1007020200000000000000511002135325000013400
Gardner Refuge 100100000000000000000000000003205
Quincy - Meyer 100404500000000000000050050070064005050018190200
Hannibal - Quincy 100700000000000000100021003101037004000003200
Saverton - Hannibal 1006010000000000000040010015003100003300
Gardner Club 100100000000000000000000005000000000
Louisiana - Saverton 100800000000000000100000100010005000001000
Shanks Refuge 10090495000660000010010010005000000500062305100330015010000510235
Delair Refuge 100901500000000000000000015002004001000000250
Sny Slough 1009030000300000500000000000335010050000000035
Twin Ponds 10010000000000000000000010000000000
Cannon Refuge 10090850001100000000000000009600100430080000033025
Batchtown Refuge 100902500050000000100150000000004600000000000
Batchtown Pool 1007030000200000010000000100010034105000000000
Cuivre Club 100908500020000002000100000000009900500100030000005
Dardenne Club 70908000015000000200000000000970010000000300
Marais Temps Clair 10090160005000000000000000165030400500003015
Grafton - Alton 1005020000000000000110030004305020000100
Long Lake 100901000000000000000000100000000000
Gilbert Lake 10090100000000001000100000003000240010000000100
Swan Lake 1009030000000000200660017000800200010001260020021003100000400
Stump Lake 100904210000000000000000042102501000105000400
Michael Godar Hurricane Diamond 10090400000000002000500600001000700079004001100100000035
Total Lower Mississippi 10791001065000015060033001560033100900860518001014509535303051017594000495601170

September 21st aerial survey

ducks from the sky

We managed to get the Illinois River flight in on Friday, September 21st. The airplane was down for maintenance early in the week and winds were excessive late in the week. The wind was gusting to 29 mph on Friday along the central Mississippi River, which prevented our flight.

We had a push of ducks into the Illinois Valley this week. Teal numbers (21,945 teal) were up 144% from last week, but down nearly 20% from the 10-yr average for the 3rd week in September. I noticed a few gadwall and American wigeon on this week’s count and northern shoveler and northern pintail numbers continue to increase. Some of our ducks may depart central Illinois this weekend as the temperatures drop into the low 50s and upper 40s. However, there is a northwest coming out of the prairies on Friday afternoon and evening, which could bring a few more teal to Illinois this weekend.

A friend and colleague of mind sent me this link the other day. The link gives a visual of real time wind movements across the country. It is a pretty unique tool to help us predict migration events. Check it out! Thanks Jeff Levengood!

How many teal and pintail do you see in the attached photo? Check out our Facebook page for the number… Good luck teal hunting on this last couple days of the season.

Stay tuned for more updates next week…

September 12th aerial survey

Those fickle blue-winged teal! They left us for the most part along the Illinois River. The remnants of Tropical Storm Gordon on September 7th and 8th increased water levels along the Illinois River. All that water coupled with the cool north winds and rain forced out our bluewinged teal on opening weekend of teal season. Similarly, recent rains across the upper Midwest have the central Mississippi River above flood stage or higher. Blue-winged teal numbers (7,715 ducks) this week were down 62% from the 10-yr average and decreased 60% from last week along the Illinois River. Blue-winged teal (8,565) on the central Mississippi River were up 95% from the 10-yr and 108% from last week; however, the majority of the teal were using the shallow waters of Swan Lake at Two Rivers NWR near the confluence of the Illinois and Mississippi rivers. Many of our refuges along the Illinois River held out the devastating flooding and the duck food plants were spared; but the Mississippi River was not so fortunate. Many of the refuges along the Mississippi lost their moist-soil plants from New Boston to Grafton and only the areas behind major levees remain intact.

Blue-winged teal (Spatula discors) prefer to feed on the sloppy mudded areas along our rivers and wetlands. Water more than a couple inches deep sends them packing for shallower foraging sites. This is why the recent rains have caused our picky bluewings to head further south. The cooler weather did bring in a few more of the early migrants like northern pintail, northern shoveler, and green-winged teal. See if you can identify them in the photo below. Good luck hunting out there!

blue-winged teal
Blue-winged teal in breeding plumage taken last spring by Ryan Askren. Note the beautiful plumage of the males while adorning their nuptial plumage. During summer/autumn migration, the plumage of males resembles that of the cryptically colored females.
blue-winged teal
Blue-winged teal in breeding plumage. Photo by Ryan Askren.
blue-winged teal
A photo of blue-winged teal from the plane with a few intermixed northern pintail and northern shoveler.
flooded Mississippi river
Mississippi River flood waters ravaging a duck blind just south of Oquawka, Illinois on September 12, 2018. Hopefully, these hunters will have time to rebuild the blind before duck season begins in late October!

Stay tuned for more updates next week…

September 7th aerial survey

We’re back at it again! We flew the first teal flight of 2018 on Tuesday, September 4th. Blue-winged teal abundance was above average (22%) along the Illinois River for the first week of September and totaled 20,340 teal. We saw average numbers of teal along the central Mississippi River (4,120 birds). The larger concentrations of teal occurred near Chillicothe, the Rice Lake Complex, Clear Lake, Chautauqua NWR, and Emiquon Preserve on the Illinois River and in the Grafton area of the central Mississippi River. Actually, I started seeing appreciable numbers of blue-wings on August 22nd while doing some shorebird flights of the Illinois River, and teal abundance has been slowly increasing every week. Wetland habitats and moist-soil vegetation (waterfowl food) along both river systems looked phenomenal this week. Let’s hope the remnants of Tropical Storm Gordon don’t ruin the bountiful crop of duck groceries out there.

Good luck with the early teal season opener on September 8th!

Stay tuned for more updates next week…

The Rice Lake Complex and Woodyard Duck Club.
Moscow Bay.
Sanganois State Fish and Wildlife Area.
Ted Shanks Conservation Area.

December 26th aerial survey

winter ducks

winter ducks

winter ducks

We flew the waterfowl survey on December 26th 2017 and the air temperature was 3 degrees. Almost everything was iced up, and when we found ducks, they were tightly packed into a little bit of open water. I have included a couple of photos to illustrate my point. Duck numbers were down considerably along both rivers, but a few of those die hard mallards and canvasbacks were holding on. For those of you still hunting ducks out there; be careful, it’s COLD! Thanks for following my blog…


December 20th aerial survey

We flew the waterfowl inventory on Tuesday, December 19th . Nearly all of the ice that formed over the last couple of weeks was gone, and we still had a bunch of ducks around for the 3rd week in December. We estimated 184,710 total ducks in the Illinois River valley, which was 31% down from last week but 30% above the 10-yr average. Similarly, mallards (153,935) were down 22% from last week but still 35% above the 10-yr average. Total ducks (796,480) on the Mississippi River dropped 8% from last week but were 142% above average. Likewise, mallards were abundant (417,185), especially in St. Charles County, MO, and were nearly double (96%) the 10-yr average.

However, the real story this week was the huge number of canvasbacks observed on Pool 19 of the Mississippi River. We estimated 246,125 canvasbacks between Nauvoo, IL and Fort Madison, IA. This raft of ducks stretched 5 miles in length and in spots approached a mile wide. This was a phenomenal number of canvasbacks when you consider this year’s breeding population of canvasbacks from the U.S. and Canada was estimated at 732,500 ducks. Even when we consider this year’s recruitment of ducklings, we very likely have less than 1 million birds in the population. So, this impressive raft of canvasbacks likely exceeded 25% of our continental population of canvasbacks. Now that’s a bunch of divers!

We tried to capture a video of the canvasbacks with a cell phone (What would we do without cell phones?). I will post the video on the Forbes Biological Station Facebook page for your viewing. Sorry for the bouncing video but that’s what it is like in the plane! Enjoy! Thanks to Joe Lancaster for the video!

Stay tuned for more updates next week…