The state of Devils Hole and the Devils Hole pupfish in 2008

Authors: Paul J. Barrett, Mike Bower, Kevin P. Wilson, John Wullschleger, Jon C. Sjoberg, Sean Harris

Year: 2008 (xl)

Abstract

At the 2007 Desert Fishes Council Symposium in Ventura California, representatives from the U.S. Fish and Wildlife Service, National Park Service and Nevada Department of Wildlife held an open discussion with the membership. Following this discussion and subsequent internal discussions within the three agencies as well as recommendations of the Recovery Team, several changes were made in the focus of the recovery program for the Devils Hole pupfish Cyprinodon diabolis. Past efforts focused on genetic analyses, disease identification, and captive propagation all of which were conducted away from Devils Hole. Although these disciplines remain important, we have shifted to understanding and manipulating the environment of Devils Hole itself. The captive propagation program has been relocated to the University of Arizona under the direction of Dr. Scott Bonar with the Cooperative Fish and Wildlife Research Unit. Until pure Devils Hole pupfish are available, the Unit will work with hybrid C. diaboli x C. mionectes fishes. Included in this work will be the culture of ostracods native to Devils Hole as a potential food for larval and juvenile growth. In addition to supplemental feeding of the pupfish in Devils Hole, we have or are in the process of, issuing contracts for a series of investigations into the biological and physical nature of Devils Hole including, a model of the physical mechanisms at work in Devils Hole, such as water temperature andturnover, examination of the physical tolerance and temperature acclimation of pupfish, quantitative habitat description of spawning locations on the shelf at Devils Hole, the isolation of eggs and larvae in floating live cars to avoid cannibalism and other predation, reevaluation of pupfish demographic data to develop more accurate methods, continued examination of the water quality parameters, research into the bacteria and other microfauna of Devils Hole and investigation of the N:P ratio and it’s effect on algae and cyanobacteria growth and competition. Bi-weekly larval surveys of Devils Hole continue as does work toward the construction of a new refuge and propagation facility near School Springs on Ash Meadows National Wildlife Refuge.