Wood Duck (Aix sponsa)
The wood duck is a commonly encountered cavity-nesting waterfowl species that breeds along the Tittabawassee River and can often be seen foraging in the shallow waters along the riverbank or within the floodplain forests. Our research aimed to determine the potential exposure of the wood duck populations residing within the Tittabawassee River floodplain to site-specific contaminants, in particular, dioxins and furans.
Wood ducks were chosen as a representative species of both the aquatic and terrestrial food webs because they forage in both habitats. Wood ducks are obligate cavity-nesters (i.e., they don’t excavate their own cavities and are dependent on natural cavities or, for this study, artificial nest boxes) and have a restricted foraging range while nesting.
Contaminant concentrations in the tissues of wood ducks were analyzed to determine their exposure to site-specific compounds. For the wood duck, collected tissues included fresh and addled eggs.
Productivity data collected on wood duck populations were limited mostly to box occupancy and clutch size.
Wood duck data have been collected from reference areas in Sanford, Michigan, and the Pine and Chippewa rivers in and around the Chippewa Nature Center, and study areas downstream of Midland, Michigan, ranging to the Shiawassee National Wildlife Refuge.
Integrating the findings from these studies provided us with the information necessary to estimate the exposure of wood ducks residing within the Tittabawassee River floodplain to site-specific contaminants.