October 29th aerial survey

As usual, the refuges along the rivers fill up with ducks the week after the central zone duck season opens. Duck season began on October 25th for most of the Illinois River valley, and duck abundance increased 55% on the refuges from the previous week. We flew the waterfowl survey on October 29th and estimated 210,315 ducks in the Illinois River valley (IRV) which was only 11.5% below the 10-yr average for late October. Similarly, the Mississippi River had 130,890 ducks which was only 12.5 % below the 10-yr average on the Mississippi (www.bellrose.org ). If you recall, duck numbers on the Mississippi have been running more than 50% below average for the last several surveys. Mallards appear to be the reason for the below average duck numbers. We are short about 50,000 mallards in the IRV when compared to the 10-yr average. The cold weather and northwest winds pushing through the central United States on Halloween may just bring the mallards we are looking for. A duck hunter can only hope!

Hunter success appeared to be about average for many areas along the Illinois River despite below average number of ducks. Hunting reports from site managers at state fish and wildlife areas in Marshall, Woodford, and Fulton counties were slightly higher than average harvest for opening weekend. However, duck harvest was 5-47% below average for the Mississippi River Area near the confluence of the Illinois and Mississippi rivers on opening weekend.

Pintail numbers have been running well above average along both rivers; however, recent pintail numbers dropped 40% in the IRV from the previous week. Weather radar documented this movement of birds out of central Illinois on the evening of October 28th. This exodus of waterbirds can be seen leaving the refuges from Chillicothe to Beardstown at sunset on the 28th.

Be safe and happy hunting! Stay tuned for more updates next week…

October 20th aerial survey

What a difference a year makes! On 23 October 2013, we had 361,000 total ducks in the Illinois River valley (IRV) which was 167% above average for this time of year. However on Monday, 20 October 2014, we had 135,060 ducks in the IRV which was 16% below the 10-yr average (www.bellrose.org ). Pintail and green-winged teal again comprised the majority (63%) of ducks in the IRV. Duck numbers were even lower along the Mississippi River where I estimated 46,625 ducks; 53% below the 10-yr average. Like the Illinois River, northern pintail and green-winged teal comprised 86% of the ducks observed. Several refuges along both rivers have unfavorable habitat conditions, and without food, duck numbers will likely be low throughout fall migration. Only time will tell I guess. October 25th marks the duck season opener in the central zone of Illinois so good luck and be safe out there.

This fall the Illinois Natural History Survey and Illinois Department of Natural Resources are conducting an experimental waterfowl “grid” survey (1-mi2 plots) along the Illinois River from Hennepin to Meredosia. The new grid survey will allow us to determine the detection probability of observing ducks from the airplane; which in turn will allow us to determine confidence intervals about our estimates of waterfowl in the IRV. For this reason, you may see us flying waterfowl surveys multiple days each week and in locations outside the 23 refuges on the traditional waterfowl survey. Please be patient with us as we embark on this new survey design. We will have more information on the project posted on www.bellrose.org in the near future.

Stay tuned for more updates next week…

October 16th aerial survey

Saturday, October 18th , marks opening day of duck season in the north zone of Illinois, and due to the abundant rains over the last several weeks, most of the waterfowl areas are full of water along the Illinois and Mississippi rivers. The Emiquon Complex and Chautauqua National Wildlife Refuge are the standouts along the Illinois River this week. Nearly 52% of the ducks I observed along the Illinois River were found at these areas. Meanwhile, Hennepin & Hopper lakes harbor the largest concentration of ducks along the upper Illinois River.

I estimated 112,585 ducks on the Illinois River on October 16th which was 11% above the 10-yr average; however, we have 33% fewer ducks than last year at this time. Duck numbers along the Mississippi River fared worse than the Illinois River and were only 50% of the 10-yr average. Northern pintail and American green-winged teal comprised nearly 63% of total ducks along the Illinois River and 88% of ducks encountered along the Mississippi River.

Stay tuned for more updates next week…

September 16th aerial survey

We flew the 3rd teal flight on Tuesday, September 16 th . Wetland habitats in the Illinois Valley are flooded extensively, yet duck abundance continues to increase despite flooding. This weekend marks the last days of the early hunting season, and Teal numbers are 24% above the 10-yr average (www.bellrose.org); however, species composition is beginning to change. Last week blue-winged teal were dominant, but now green-wings outnumber blue-wings nearly 3:1. Additionally, American coots are up threefold from last week. The cooler temperatures over the last several days likely pushed the blue-wings further south.

The last couple weeks I have discussed wetland habitat conditions and the availability of duck foods during fall; however, I haven’t explained what it takes to provide a smorgasbord for waterfowl. Ideally, we would like to see water levels drop during mid-June to early-July along the rivers. As floodplain waters recede, mudflats are exposed allowing seeds to germinate. Our studies at Chautauqua National Wildlife Refuge found that 1,800 pounds/acre of moist-soil seeds were produced with a late June/early-July drawdown, whereas, only 500 pounds/acre were produced when the drawdown was delayed a month (i.e., early-August). Obviously, the more food we have available during fall, the more duck use days we can support, which ultimately provides more recreational opportunity for our waterfowl hunters.

Stay tuned for more updates next week…

graph
Figure 1. Estimates of stopover duration (days) for ducks and an annual index of foraging habitat quality (1 = poor, 2 = fair, 3 = good, 4 = very good, 5 = excellent) in the Illinois River valley during falls 1996, 1997, 2003, and 2005–2009.

September 11th aerial survey

flooded wetlands
Many wetlands along the Illinois and Mississippi rivers were deeply flooded following rainstorms on September 9th and 10th. Illinois River water was rapidly filling Spunky Bottoms south of Beardstown, IL, on September 11th.

The rain finally stopped and we were able to get in the air for the 2nd teal flight on Thursday, September 11th . A major rain event like this week (4–8 inches over the Illinois River watershed) makes our rivers jump drastically. Water levels at Havana jumped 6 feet in two days and the water is still rising. Certainly this flooding will destroy most of the duck food remaining in the Illinois Valley. Only wetlands protected behind major levee systems will be spared from flooding (i.e., Chautauqua NWR, Emiquon Preserve, and Hennepin & Hopper Lakes). On a brighter note, many duck clubs and public waterfowl areas along the river will save on pumping costs this year.

There were only minor changes in waterfowl abundance this week. Teal numbers in the Illinois River valley were up by 4,800 birds, and both blue-winged and American green-winged teal were near their 10-year averages (www.bellrose.org). Most of the increase was due to a small advance in the green-winged teal numbers in the Illinois Valley. Teal numbers on the Mississippi River were again low this week and only totaled 1,820 birds at census locations; 70% below 10-yr averages. Hopefully, cooler weather will increase duck numbers along both rivers before the last week of teal season. Teal season is scheduled to close at sunset on September 21st.

Stay tuned for more updates next week…

September 3rd aerial survey

The first teal flight for fall 2014 is in the books. Duck numbers for the Illinois River exceeded the 10-yr weekly average by 21% and totaled 32,910 total ducks. Blue-winged and American green-winged teal abundance (21,540) was similar to the 10-yr average (21,975). Total ducks on the Mississippi River were well below the 10-yr average and totaled 6,109 ducks. The September 4th weather forecast in North Dakota predicts strong northwest winds at sunset; maybe we will get a big push of teal out of the prairies before this weekend’s teal season opener.

My early September estimate of wetland habitat conditions for waterfowl this fall ranks well below average for both the Illinois and Mississippi rivers. It has been a rainy summer and consequently the Illinois River has been elevated for most of the growing season. The last rise in water levels on August 23rd destroyed much of the waterfowl foods in the unprotected wetlands of the Illinois Valley. Most of the refuges and duck clubs along the Mississippi River had below average moist-soil plant growth as well. Some notable exceptions include Dardenne, Cuivre, and Port Louisa on the Mississippi River and Hennepin & Hopper, Douglas Lake, Banner Marsh, Emiquon, Cuba Island, Big Prairie, and Spunky Bottoms along the Illinois River. Other refuges, like Chautauqua NWR, were able to achieve a late-season drawdown so they will have some duck food; however, plant growth at many wetlands along both rivers was a bust this summer.

Stay tuned for more updates next week…

December 13th aerial inventory

We flew the Illinois and Mississippi river waterfowl survey on Thursday, December 12th. There wasn’t much open water anymore. The old saying, “Stick a fork in it, I think we are done” comes to mind! A colleague of mine said, “you can tell the haves from the have nots”. He was referring to hunters that have the ability to maintain open water and those that can’t. Almost all of the Illinois River was frozen with the ducks piled into a few open water spots. This week was one of a few times since I began doing the survey in 2005 that Dardenne and Cuivre in St. Charles County, Missouri were frozen. These refuges generally hold 30,000 to 50,000 ducks each in December. The Illinois River had 108,665 total ducks which was nearly 40% below the 10-yr average for this week of December. The Mississippi River faired a little better than the Illinois, but it was still 22% below average. Pool 19 was almost completely frozen and most of the divers had departed. I guess we will have to hunt geese for the rest of the season. Good Luck and stay warm… Stay tuned for more updates next week…

December 6th aerial inventory

I flew the Illinois River waterfowl survey on Friday. We had about 125,000 ducks which was down about 40% from last week and about 50% below the 10-yr average; see www.bellrose.org for more details. Many of the refuges had significant ice coverage on Friday, and with the low temperatures and projected forecast, I anticipate many areas are completely iced up by Sunday morning. This doesn’t mean that all the ducks have left the Illinois River. Mallards are keen at finding open water and keeping it open. Those duck hunters that have the ability to maintain open water will continue to harvest mallards, but the rest of us will have to hit the corn fields to duck hunt.

Good Luck and stay warm….it’s cold out there! Stay tuned for more updates next week…

November 29th aerial inventory

Ice ducks! I flew the Mississippi River on Friday November 29th. It appears there was a major migration into the region. Nearly 3/4 of a million birds on the Mississippi. Canvasbacks arrived in big numbers on Pool 19, and mallards are holding on in small pockets of open water at many refuges. However, we lost the majority of the non-mallard dabblers. The following is a photo of what mallards look like from the air when the wetlands start icing up. Numbers are posted at www.bellrose.org.

Stay tuned for more updates next week.

November 20th aerial inventory

There are still a bunch of ducks along both the Illinois and Mississippi rivers with 600,330 and 597,335 total ducks, respectively. These numbers are very similar to what was here last week. Actually, I think these ducks have been here for a couple weeks now. Many duck clubs and public land hunters are telling me that the harvest has dropped off over the last several days. Hunters like to call these birds “stale”. In other words, they have been in the area for too long and have figured out where the refuges are. They are duck blind, decoy, and call shy. Duck hunting is best when we have many smaller duck migrations into Illinois. These new influxes of ducks every 4 or 5 days create a situation where new birds are mingling around the various wetlands trying to find food and refuge. Therefore, they are more naïve and huntable than ducks that have been around for a while.

Speaking of harvest, where do you think our mallards come from? The accompanying slide shows where mallards harvested in Illinois breed. Band recovery data from the 1990’s shows that while we still get a lot of our birds from the prairies, the percentage of mallards coming from the Great Lakes states has increased substantially since the 1960’s. Over 28% of our mallard harvest comes from ducks reproducing in Minnesota, Wisconsin, Michigan, Indiana, Iowa, and yes, right here in Illinois. Let’s hear it for the Conservation Reserve Program for putting grasslands back on the landscape!

Good luck in the deer stand this weekend and stay tuned for more updates next week…