Standard Fish Sampling Techniques and Environmental DNA (eDNA) As Tools to Characterize Fish Presence and Relative Abundance in Arizona Standing Waters

Recently, examination of deoxyribiose nucleic acids in water samples (environmental DNA or eDNA) has shown promise for identifying fish species present in water bodies. In water, eDNA is the result of bodily secretions such as mucus, gametes, and feces. We are investigating whether eDNA can be effective for estimating fish species biomass and relative abundance in waterbodies. Our primary objectives are to relate data on fish species presence, relative abundance, and biomass collected by traditional methods, such as electrofishing and gill netting, to data from eDNA in water collected concomitantly at the same sites. Study sites include a large reservoir (Theodore Roosevelt Lake, Arizona) and ~20 small (< 200 ha) Arizona lakes. The analysis for the large reservoir study site was a within impoundment comparison of sites in Lake Roosevelt. The analysis for the small lakes will include an across impoundment comparison of the ~20 lakes. Further evaluation of environmental DNA is necessary to identify its utility in standard fish monitoring. If proven a reliant technique the use of eDNA can be a cost effective and time saving tool for mangers to obtain fisheries information from small or remote sites and large waterbodies.