To evaluate the possible effects of dioxins and furans from the environment on the Tittabawassee River floodplain’s wildlife community, specific wildlife species (typically a top predator of a particular food web), were selected as receptors to represent the species of the floodplain with similar feeding and nesting habits.
American robins, eastern bluebirds, house wrens and tree swallows were selected to represent the songbird (passerine) species of the Tittabawassee River floodplain. Although each species is a representative of the same taxonomic order, the dietary preference and nesting habitat selection vary significantly, which was ideal for evaluating the potential effects on the songbird community as a whole.
Wood ducks and hooded mergansers were selected to represent the cavity-nesting waterfowl. These waterfowl have similar nesting habitat preferences but differ in dietary needs; wood ducks dabble on surface vegetation and invertebrates, while hooded mergansers dive for fish.
Great blue herons and belted kingfishers were selected to represent the fish-eating (piscivorous) birds of the floodplain. Nesting habitat varies significantly between these two species. Great blue herons nest communally in rookeries located high in trees while belted kingfishers prefer to nest in subterranean burrows dug in the bank away from other breeding pairs in distinct foraging territories.
The great horned owl was selected to represent the carnivorous raptors of the Tittabawassee floodplain. The great horned owl diet consists of mammals of various sizes, usually no larger than a cottontail rabbit and birds typically no larger than a duck.
The American mink was selected to represent the carnivorous mammals of the floodplain. The American mink forages in the river for fish and muskrat as well as along the riverbank and the emergent forest for small mammals, such as mice.