Wetland restoration efforts along the Illinois River face challenging questions regarding river connectivity and water management. To improve understanding of the functional relationship among river connectivity, wetland hydrology, and use by migratory shorebirds, we surveyed a wetland complex along the Illinois River during the spring and summer/fall migrations of 2003 and spring migration of 2004. Twenty-four species of shorebirds and over 150,000 shorebird use-days were recorded. Migration chronologies varied significantly among sites, with time lags ranging from 0 to 52 days during a single spring or summer/fall migration. Wetland impoundments with greater connectivity to the Illinois River were vulnerable to flood events, resulting in sporadic use by shorebirds. Management at impoundments with more protection from flood events provided more consistent shorebird habitat. The Illinois River is designated as a stopover region of international importance for shorebird conservation due to its extensive use by shorebirds during the summer/fall migration. However, the density of shorebird use during the spring migration was also high in the second year of our study, demonstrating that shorebird counts at single stopover locations or for a single year can lead to incorrect conclusions about migration chronology and provide misleading directions for management. To improve stopover habitat for migrating shorebirds, we recommend a balance among strategies for managing hydrology and cooperation among landowners to provide diverse habitat with available alternative sites in case traditional habitat is lost during floods or droughts.
|Original language||English (US)|
|Journal||Transactions of the Illinois State Academy of Science|
|State||Published - 2008|