A New Las Vegas Home for the Pahrump Poolfish, Empetrichthys latos

Authors: Aaron Ambos, Raymond Saumure, Thomas O’Toole, Zane Marshall

Year: 2018

Abstract

In May 2018, two-hundred and fifty adult Pahrump Poolfish, Empetrichthys latos, were released into two constructed ponds at the Las Vegas Springs Preserve in Las Vegas, Nevada. This introduction marks the first time in over fifty years that a Nevada endemic fish swims at the site of the historic Las Vegas springs. Once a lush oasis within an arid Mojave Desert landscape, the Las Vegas spring complex ceased flowing prior to 1962 due to increasing groundwater usage. Endemic to the spring complex, the Las Vegas Dace, Rhinichthys deaconi, disappeared from the system around 1957, but was not officially declared extinct until after its formal description by Miller in 1984. In the following decades, the site existed solely as a well field, providing water for the growing Las Vegas community. In 1997, however, the Las Vegas Valley Water District Board of Directors approved a plan to develop a 180-acre preserve to protect and manage the natural, cultural, and water resources of the site. The Springs Preserve opened in June 2007, and by 2010 plans were made to restore some surface water habitat within the original creek channels. The federally endangered Pahrump Poolfish was identified as a possible candidate to inhabit these ponds as it is a Nevada native species, tolerant of a broad range of water conditions, and in need of an additional refuge population. Permits for the Pahrump Poolfish were obtained in 2017 and included a Nevada Department of Wildlife Scientific Collection Permit, a U.S. Fish and Wildlife Enhancement of Survival permit, and a U.S. Fish and Wildlife Safe Harbor Agreement. The initial two ponds were completed in early 2018 and Pahrump Poolfish from an existing refuge population were introduced on May 29. By June 18, dozens of ~5-mm long larval poolfish were observed in the shallows, and by August multiple age-classes were observed throughout the ponds. Pahrump Poolfish may eventually be introduced to an additional eight ponds on the Springs Preserve property.