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…