Hooded Merganser

The hooded merganser is a commonly encountered species that breeds along the Tittabawassee River and can often be seen foraging along the river. Our research aims to determine the exposure of the hooded merganser population that resides within the Tittabawassee River floodplain to site-specific contaminants, specifically dioxins and furans.

Hooded mergansers were chosen as a representative species of the aquatic food chains because they forage primarily on fish. Hooded mergansers are obligate cavity nesters (i.e., they don’t excavate their own cavities and are dependent on natural cavities or, more importantly, nest boxes), have a restricted foraging range while nesting, and are located near the top of the aquatic food chain.

Contaminant concentrations in the tissues of hooded mergansers are analyzed to determine their exposure to site-specific compounds. Specifically for the hooded merganser, tissues collected include fresh and addled eggs.

Productivity data collected on hooded merganser populations are limited mostly to box occupancy and clutch size.

Hooded merganser data have been collected from reference areas in Sanford, Michigan, and the Pine and Chippewa rivers in and around the Chippewa Nature Center to downstream of Midland, Michigan, ranging to the Shiawassee National Wildlife Refuge.

Integrating the findings from these studies will provide us with the information necessary to estimate the exposure of hooded mergansers residing within the Tittabawassee River floodplain to site-specific contaminants.