Current status and future management directions of the Devils Hole pupfish

Authors: Michael Schwemm, Kevin Wilson, Jeffrey Goldstein, Ambre Chaudoin, John Wullschleger, Corey Lee, Olin Feuerbacher, Javier Linares, Brandon Senger

Year: 2017 (xlix)

Abstract

The Devils Hole pupfish (Cyprinodon diabolis) of southern Nevada occurs in likely the smallest habitat of a vertebrate taxon, and as such exhibits a precarious and complex history of conservation management This report updates the Desert Fishes Council on the current status and future management of the species The most recent census at Devils Hole (a semi-annual estimate by direct count) was 115 fish on September 16 and 17, 2017 This count was lower than fall counts of immediately prior years 2016 or 2015 (144 and 131 fish, respectively) Nonetheless, because life-history attributes, seasonality and stochastic impacts on habitat strongly influence short-term demography, 2017 results are not extraordinary in this system over the past three years Instead, the relative stability at a population size far below historic levels represents an ongoing management concern The sole refuge population outside of Devils Hole at the Ash Meadows Fish Conservation Facility houses approximately 60 additional animals in the refuge tank, and 25 animals collected as eggs from Devils Hole over the preceding fall (2016) and spring (2017) Animals housed in the refuge tank consists of all life-stages, indicating natural recruitment Similar to the Devils Hole population, the level of recruitment and population size in the refuge tank is lower than expected given habitat size and productivity Potential explanations for observed population sizes and ongoing research objectives will be discussed