The bioconcentration factor (BCF) of per- and polyfluoroalkyl substances (PFASs) was determined in residential Black Swans (Cygnus atratus) from an urban lake (Melbourne, Australia). The concentrations of 46 PFASs were determined by HPLC-MS/MS in serum and excrement from swans, and water, sediment, aquatic macrophytes, soil and grass samples in and around the lake. Concentrations detected in the water, sediment and swans was consistent with a highly impacted ecosystem. The BCF of PFOS was measured at 1.12 mL/L, while the BCF of perfluorocarboxylic acids (PFCAs) increased with CF2 moiety from PFOA (0.0156 mL/L) to PFDoDA (3.61 mL/L), indicating that further research is warranted for long-chain PFASs, especially in underrepresented lower trophic avian species. PFHxS was detected in the serum of 100% of swans (n = 22) and was negatively correlated with body condition (Spearman’s R = -0.53, p = 0.012). This is the first study to determine: (1) the concentrations of PFASs in Australian swans and, (2) the potential for a non-invasive technique for PFASs body burden in birds using excrement.