Figure 1.

Sampling locations at an established tree swallow colony approximately 250 m from the effluent outflow of a major urban wastewater treatment plant (WWTP, Hamilton) that used secondary treatment processes at the time of the study. Sediment (green circles) and aquatic invertebrate (orange circles) sampling collections occurred 250 m downstream from the tree swallow colony. Air samplers were deployed within the active tree swallow colony (marked by X). Terrestrial invertebrate sampling occurred in the area that tree swallow adults were observed feeding within and surrounding the colony.