Conservation of Cyprinodon nevadensis pectoralis and three endemic aquatic invertebrates in an artificial desert spring refuge located in Ash Meadows National Wildlife Refuge, Nevada by Darrick S. Weissenfluh, B.S. A Thesis In BIOLOGY Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCES Approved Dr. Gene R. Wilde Chair Dr. Nancy E. McIntyre Dr. Richard E. Strauss Ralph Ferguson Dean of the Graduate School December, 2010 Copyright 2010, Darrick S. Weissenfluh Texas Tech University, Darrick S. Weissenfluh, December 2010 ACKNOWLEDGEMENTS I would like to thank my advisor, Dr. Gene R. Wilde, for accepting me as a graduate student and for working with me remotely. I also wish to thank him for challenging me to communicate more effectively through writing. Dr. Nancy E. McIntyre and Dr. Richard E. Strauss also provided recommendations and critiques of my work and were valuable committee members. Many people unselfishly assisted me with collecting data in what seemed to be the most extreme Mojave Desert field conditions: Jeff Goldstein, Sam Skalak, Erin Bradshaw, April Bradshaw, Cristi Baldino, Mark James, Carl Lundblad, and Paula Booth. Sam Skalak and Cristi Baldino also provided valuable comments and suggestions concerning my paper and my study. Additionally, Paula Booth and Marie Weissenfluh interpreted poor writing on numerous data sheets while assisting with data entry. Kathie Taylor spent countless hours assisting me with GIS maps and database development, for which I am indebted. The design of my research site, School Springs, was largely the creation of Rob Andress and the Ash Meadows Recovery Implementation Team (AMRIT). On numerous occasions Rob and the AMRIT went out of their way to assist with questions and data needs related to my research. Sharon McKelvey, Cristi Baldino, and Heather Hundt worked with Cynthia Martinez to make my position at Ash Meadows National Wildlife Refuge possible and supported me throughout my collateral duty as a U.S. Fish and Wildlife Service Student Career Employment Program biologist and graduate student. ii Texas Tech University, Darrick S. Weissenfluh, December 2010 Thanks to their support and encouragement I have had the opportunity to assist the Refuge in obtaining important scientific information while continuing to pursue my career. Finally, I am indebted to my wife Marie Weissenfluh who unselfishly allowed me to pursue this degree and dealt with all my stress and distraction during the process. My daughter, Kaitlyn, is owed countless hours for allowing “Daddy” to spend too much time away from her. I look forward to spending more time with both of them. My parents Steve and Diana, brother Shawn, and sister Holly also supported and encouraged me to continue my education and for that I am grateful. iii Texas Tech University, Darrick S. Weissenfluh, December 2010 TABLE OF CONTENTS ACKNOWLEDGEMENTS .............................................................................................. ii ABSTRACT……………………………………………………………………………..vi LIST OF TABLES ......................................................................................................... viii LIST OF FIGURES ........................................................................................................... x I. INTRODUCTION ......................................................................................................... 1 Literature Cited ....................................................................................................... 6 II. HABITAT ASSOCIATION AND DISTRIBUTION OF ENDANGERED WARM SPRINGS PUPFISH, CYPRINODON NEVADENSIS PECTORALIS, IN SCHOOL SPRINGS REFUGE ................................ 9 Introduction ............................................................................................................. 9 Study Area ............................................................................................................ 12 Methods................................................................................................................. 16 Study Design ............................................................................................. 16 Determination of Life Stages Using Digital Images ................................. 18 C. n. pectoralis Habitat Association ......................................................... 20 Physical and Chemical Stream Variables in School Springs Refuge ....... 21 Results ................................................................................................................... 22 Non-native Aquatic Fish and Crayfish Eradication Results ..................... 22 Status of C. n. pectoralis in School Springs Refuge ................................. 22 C. n. pectoralis Habitat Association in School Springs Refuge ............... 24 Discussion ............................................................................................................. 24 School Springs Refuge Renovation: Was it a Success? ............................ 24 Does School Springs Refuge Reduce the Threats to C. n. pectoralis Conservation? ........................................................................................... 28 Determining C. n. pectoralis Length from Digital Images ....................... 30 Recommendations for the Management of School Springs Refuge ......... 31 Literature Cited ..................................................................................................... 34 iv Texas Tech University, Darrick S. Weissenfluh, December 2010 III. ENDEMIC AQUATIC INVERTEBRATE DISTRIBUTION AND ASSOCIATION WITH PHYSICAL AND CHEMICAL STREAM PROPERTIES IN SCHOOL SPRINGS REFUGE ............................... 51 Introduction ........................................................................................................... 51 Study Area ............................................................................................................ 54 Methods................................................................................................................. 55 Aquatic Invertebrate Distribution in School Springs Refuge ................... 55 Endemic Aquatic Invertebrate Association with Physical and Chemical Stream Properties in School Springs Refuge ............................................ 57 Results ................................................................................................................... 58 Non-native Aquatic Invertebrate Eradication in School Springs Refuge ....................................................................................................... 58 Endemic Aquatic Invertebrate Translocation ........................................... 59 Persistence of Endemic Aquatic Invertebrates in School Springs Refuge ....................................................................................................... 59 Distribution and Dispersal of Endemic Aquatic Invertebrates in School Springs Refuge .......................................................................................... 61 Endemic Aquatic Invertebrate Distribution and Their Association with Chemical and Physical Stream Properties in School Springs Refuge ...... 63 Discussion ............................................................................................................. 64 Evaluating the Translocation Success of Endemic Aquatic Invertebrates in School Springs Refuge .................................................... 64 Evaluating the Success and Design of School Springs Refuge ................ 68 Management Recommendations ............................................................... 71 Literature Cited ..................................................................................................... 74 A. SCHOOL SPRINGS REFUGE CHANNEL CHARACTERISTICS FOR EACH REACH ........................................................................... 100 B. SUMMARY STATISTICS FOR PHYSICAL AND CHEMICAL STREAM CHARACTERISTICS IN EACH REACH FROM SCHOOL SPRINGS REFUGE. ALL SAMPLES FROM 6 MARCH 2009 TO 3 MARCH 2010 WERE COMBINED .............. 101 v Texas Tech University, Darrick S. Weissenfluh, December 2010 ABSTRACT The Warm Springs Complex (WSC) is one of four management units within Ash Meadows National Wildlife Refuge. It contains six low-discharge warm spring systems with individual flows ranging from 1.13 x 10-4 to 1.98 x 10-4 cubic meters per second and spring-source water temperatures ranging from 28o to 33.5oC year round. School Springs is one component of the WSC and its spring source is the warmest. This spring has undergone dramatic anthropogenic transformation since at least the 1930s. In 1969 the Bureau of Land Management (BLM) increased pool habitat in School Springs in an effort to preserve the endangered Warm Springs pupfish, Cyprinodon nevadensis pectoralis. Four concrete ponds were constructed at School Springs in 1983 to further increase available habitat to C. n. pectoralis. During the summer of 2008, the School Springs refuge was completely renovated: the large concrete ponds were removed and a “naturalized” channel consisting of pools, runs, riffles, and a wash was created. There were three primary objectives of this renovation: (1) eradicate three aquatic non-native species including western mosquitofish Gambusia affinis, red swamp crayfish Procambarus clarkii, and red-rimmed melania Melanoides tuberculatus; (2) improve amount of suitable habitat for the endangered Warm Springs pupfish and three