Virgin River Chub Gila seminuda apparent response to high flows in the

Authors: lower Virgin River

Year: 2016 (xlviii)

Abstract

Rogers, Ronald *1, Albrecht, Brandon1, Ambos, Aaron2, Kegerries, Ronald1. (1-BIO-WEST , 2-Southern Nevada Water Authority).

BIO-WEST Inc., in cooperation with the Southern Nevada Water Authority (SNWA), the U.S. Bureau of Reclamation, and members of the Lower Virgin River Recovery and Implementation Team, have been monitoring the native fish community, more specifically the endangered Virgin River Chub Gila seminuda, in the lower Virgin River (river kilometer 140–104) since 2009. Following several high flow events, increased catch rates, a decrease in mean total length, and elevated numbers of small, wild G . seminuda were observed during long-term monitoring from 2009–2015. Additionally, multiple size classes were detected during this same time period, suggesting that recent recruitment of this species has occurred in the Virgin River. While the impact of high flow events on the G . seminuda population is not fully understood, it is evident that they are a benefit to the species. Long-term monitoring provides valuable information about the G . seminuda population and will potentially answer some of the persistent questions about how high flow events impact this species and the habitat in which it lives. Future studies will continue to enhance our knowledge of this species and aid management and conservation decisions.