Waterbird response indicates floodplain wetland restoration

Despite extensive anthropogenic degradation of most wetlands and other aquatic habitats associated with large rivers in the Midwest, the region still supports continentally important numbers of waterbirds during autumn and spring migration; however, few data exist to evaluate wetland restoration success and identify thresholds where changes in management may be necessary to meet conservation targets. We tracked waterbird response to restoration of a historical floodplain wetland complex along the Illinois River during 2007–2013 relative to waterbird use of other wetlands and floodplain lakes in the region. Dabbling ducks and other waterbirds showed dramatic responses to restoration, each accumulating more than 3 million use-days/year and comprising more than 30% of the total waterbird use-days in the Illinois River Valley during autumn and spring migrations. We identified use that was strongly disproportionate to availability within the region for several waterbird taxa and documented nesting by several species of conservation concern. Many species and foraging guilds of waterbirds [e.g., American coot (Fulica americana), dabbling ducks (Anatini)] responded rapidly to wetland restoration, continued to use Emiquon Preserve regardless of changing conditions at reference sites, and showed relatively limited temporal variation, thereby demonstrating their utility as indicators of habitat conditions and restoration trajectory.