Comparisons of Banded Killifish Condition Among Wastewater Impacted and Control Sites

Abstract

Banded Killifish, Fundulus diaphanus, are temperate freshwater fish that are native to the Potomac River. They are an indicator species since they adapt a stationary lifestyle playing a key role in the aquatic food chains. For this study, killifish were collected at Hunting Creek and Gunston Cove, which receive treated wastewater. Additional killifish were collected from a control waterbody, Kanes Creek, without wastewater input. Killifish were collected with a seine, measured (Standard Length [SL] mm), and weighed (g). Relative condition, Fulton’s condition factor, and SL were compared among waterbodies using a linear mixed effect model with a unique c0llection date as a random effect to protect against pseudoreplication. No significant differences were detected among any variables. However, when mean (∓ SE) is plotted across individuals, a trend is present where Kanes Creek has the largest fish in the best condition, followed by Gunston Cove, and Hunting Creek. These results indicate that wastewater effluent or some other environmental factor (e.g. loss of aquatic plants) may adversely affect Banded Killifish condition; however, more sampling events are needed to statistically elucidate these potential impacts.