Polychlorinated dibenzofuran (PCDF) and polychlorinated dibenzo-p-dioxin (PCDD) concentrations in floodplain soils and biota downstream of Midland, MI, USA are greater than regional background concentrations. A multiple lines of evidence approach was utilized to evaluate the potential for effects of PCDD/DFs to American robins (Turdus migratorius ; AR) breeding in the floodplains from 2005–2008. A dietary-based hazard assessment indicated there was potential for adverse effects for ARs that were predicted to have the greatest exposures; conversely, a tissue-based exposure assessment based on on-site eggs indicated minimal potential. A reproductive endpoints assessment indicated measures of hatch success for the study areas (SA) were significantly less than those of reference areas (RA), however there was no contaminant dose-response relationship. Given the dietary-based exposure and reproductive endpoint assessments were in accordance, the present study suggests potential for adverse effects to resident ARs exists and effects were observed. However, the tissue-based assessment suggests no potential for adverse effects and is reinforced by the fact the response was not dose-related. It is likely the dietary assessment is overly conservative based on the inherent uncertainties of estimating dietary exposure relative to the direct measure of the tissue-based assessment. As such, ARs are not expected to be at risk to potential adverse effects of exposure to PCDD/DFs.