Reduced nest predation of cavity-nesting Wood Ducks during flooding in a bottomland hardwood forest

The importance of flooding to birds that nest in bottomland hardwood forests is poorly understood, in part because floods are difficult to predict. A large flood occurred in 2002, during Our study of cavity-nesting Wood Ducks (Aix sponsa) in the Mississippi River floodplain. Nests were depredated prior to and after, but not during, the four-week flood. This observation prompted a retrospective analysis of flooding, nest predation, and nest success for our three-year study period of 2000-2002 and with a dataset extending back to 1995. Nest predation was lower and nest success was higher in the floodplain during floods. Flood conditions did not significantly affect nest success or nest predation rates in the adjacent upland, but nest success in upland forest was higher than in the floodplain during dry periods. Historically, spring flooding of riparian areas may to some extent have mitigated nest predation in bottomland forests.