The Illinois River Valley (IRV) provides critical stopover habitat for migrating waterfowl during spring and autumn. Because spring migration is an important time for waterfowl as they enhance body condition in preparation for the breeding grounds, the UMRGLR Joint Venture relies on the IRV and other migratory focal areas in Illinois to protect, maintain, enhance, and restore more than 80,000 ha of wetland habitats for waterfowl. Green-winged teal (GWTE; Anas crecca) usually rank in the top 4 species in the Illinois duck harvest, and primarily consume natural foods during migration, often selecting for seeds and invertebrates over agricultural grains. In order to provide current information on wetland habitat needs for GWTE to wetland and natural resource managers, we experimentally collected foraging GWTE during the spring in the IRV from the confluence of the Illinois and Mississippi rivers extending north to Hennepin, Illinois, during springs 2016–2018. We removed upper digestive tracts and estimated food availability (benthic and nektonic samples) at foraging sites to evaluate food use and 4$^th$ order selection. We analyzed diets from the upper gastrointestinal (GI) tract (proventriculus and esophagus), as well as gizzards. Further, we performed proximate analysis on the teal carcasses to analyze body condition in relation to diet. We will discuss overall food use and selection by GWTE, as well as preferences of plant and invertebrate taxa in comparison with food availability.
|Original language||English (US)|
|Title of host publication||Midwest Fish and Wildlife Conference 2019|
|State||Published - 2019|