Ecological Complexity of Non-Native Species Impacts In

ECOLOGICAL COMPLEXITY OF NON-NATIVE SPECIES IMPACTS

IN DESERT AQUATIC SYSTEMS

A Dissertation Submitted to the Graduate Faculty of the North Dakota State University of Agriculture and Applied Science

Sujan Maduranga Henkanaththegedara

In Partial Fulfillment for the Degree of DOCTOR OF PHILOSOPHY

Major Program: Environmental and Conservation Sciences

March 2012

Fargo, North Dakota

North Dakota State University Graduate School

Title

ECOLOGICAL COMPLEXITY OF NON-NATIVE SPECIES IMPACTS

IN DESERT AQUATIC SYSTEMS

Sujan Maduranga Henkanaththegedara

The Supervisory Committee certifies that this disquisition complies with North Dakota State University’s regulations and meets the accepted standards for the degree of

DOCTOR OF PHILOSOPHY

SUPERVISORY COMMITTEE:

Dr. Craig Stockwell Chair

Dr. Mark Clark

Dr. Malcolm Butler

Dr. Bernhardt Saini-Eidukat

Approved by Department Chair:

03.02.12 Craig Stockwell

Date Signature

ABSTRACT

Without an adequate understanding of complex interactions between native and non- native species, management of invasive species can result in unforeseen detrimental impacts. I used both field and laboratory experiments to study reciprocal species interactions between the endangered Mohave tui chub (Siphateles bicolor mohavensis) and invasive western mosquitofish

(Gambusia affinis). I also examined the impacts of both fish species on the aquatic invertebrate communities in desert springs.

I demonstrate a case of intraguild predation (IGP) as a mechanism facilitating co- persistence of the endangered Mohave tui chub with invasive mosquitofish using field mesocosm experiments. In this case of IGP, adult tui chub prey on adult and juvenile mosquitofish, while adult mosquitofish prey on tui chub eggs and/or larvae.

I conducted laboratory predation trials to assess if IGP was size-structured due to predator gape-limitation. I explored sex specific differences in gape-size limitation in mosquitofish, because mosquitofish are sexually dimorphic. Larval tui chubs had lower survival in the presence of female mosquitofish than in the presence of males. Reciprocally, male mosquitofish had lower survival than the females in the presence of Mohave tui chub. These results combined with vulnerability modeling supported that IGP in this system is size structured based on gape-size limitation.

These results collectively suggest size-structured IGP may facilitate the co-persistence of these two fish species. My findings also suggest that mosquitofish may not be a limiting factor for the persistence of the endangered Mohave tui chub. Further, habitats currently harboring mosquitofish were considered as future refuge habitats for Mohave tui chub, a management option previously un-available.

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In addition to such reciprocal interactions between fish species, recently established fish populations may impact unique invertebrate communities. Mesocosm experiments with sympatric and allopatric populations of tui chub and mosquitofish showed negative impacts of both fish species on changes of invertebrate community structure. Specifically, fish caused population declines and, in some cases, extirpations of various invertebrate taxa. These results suggest important conservation implications of invasive fish as well as protected fish transplants into fishless desert springs.

Overall my research emphasizes the complexity of ecological interactions between native and non-native fish species in desert aquatic systems.

ACKNOWLEDGEMENTS

This dissertation would not have been possible without the assistance, encouragement and blessings of many individuals and institutes. First of all, I thank my major advisor, Dr. Craig

Stockwell, for accepting me as his first international student into his lab and guiding me not only through all the steps of my dissertation research and academic achievements, but also my

“American life.” In addition, my dissertation committee members, Dr. Mark Clark, Dr. Malcolm

Butler and Dr. Bernhardt Saini-Eidukat, supported this work in many ways including, encouragement, advice and critiques of my work as it has progressed through its various stages. I thank Dr. Mangala Ganehiarachchi who made the initial bridge between me and Dr. Stockwell;

Dr. David Wittrock, Dean of the NDSU Graduate School and Dr. William Bleier, former Chair of the NDSU Department of Biological Sciences for their support for my graduate work.

Administrative assistants of the Department of Biological Sciences, Suzy Schmoll, Rita Slator,

Valerie Kleppen and Phyllis Murray, deserve a special thank.

I am indebted to many of my colleagues for their support for my work over the last six years. I owe sincere and earnest thanks to Stockwell Lab members, Dr. David Mushet, Dr.

Yongjiu Chen, Dr. Kevin Purcell, Ali Tacket, Justin Fisher, Shawn Goodchild, and Brandon

Kowalski; faculty and staff of the NDSU Department of Biological Sciences, and colleagues of the Biological Sciences, Dr. William Clark, Dr. Daniel McEwen, Joe Allen, Allison Hagemiester and Emily Berg for their intellectual stimulation through friendship, discussions, critiques as well as assistance with some field and laboratory experiments.

I thank my field assistants, Eric Hanson, Nathan Stroh, Justin Fisher and Brandon

Kowalski. I want to extend my special thanks to Justin Fisher and Brandon Kowalski for their dedication to my field experiments in 2009. Additional research and logistical assistance in the

v field were provided by Dr. William Presch, Rob Fulton, and Jason Wallace (Desert Studies

Center); Dr. Debra Hughson, Jason Dungan, and Neal Darby (Mojave National

Preserve/National Park Service); Steve Parmenter, Kim Milliron, and Jane Lester (California

Department of Fish and Game); Susan Williams, Steve Pennix and Anna-Marie Easley (China

Lake NAWS); Matthew Huffine (Lewis Center for Academic Excellence) and his family, Bruce

Kenyon, Jeff Siegel, and Samson Lamech. William Clark and Benjamin Nelson assisted with aging fish. Additional assistance for my research was provided by undergrad research volunteer mentees at NDSU, Steven Burdick, Benjamin Nelson, Natalie Verworn, Joshua Melhorn, and

Sayuri Yang. I thank Curt C. Doetkott (NDSU Statistical Consulting Service) and Dr. Dan

McEwen for support with statistical analysis of my data. I thank Justin Fisher for the Mohave tui chub distribution map he created with short notice.

I like to pass my extreme gratitude to Steve Parmenter, California Department of Fish and Game and Dr. Debra Hughson, Mojave National Preserve/National Park Service, not only for their roles in instigating this research and their assistance in the process of both federal and state permits, but also for their information, advise, and encouragement. Also I thank John

Wullschleger for his support and contributions in review the original research proposals, and

Judy Hohman and Michael Glenn (U.S. Fish and Wildlife Service) for their assistance with federal permits. Steve Pennix, Susan Williams and Anna-Marie Easley deserve my gratitude for their help with obtaining proper permission to work in China Lake Naval Air Weapons Station, assisting with fish collections, mark-recapture studies, and sharing unpublished census reports.

This work was supported, in part, by a National Park Service Grant (Grant # 43500-2715-

FAR0012031) to Dr. Craig Stockwell, two Western National Parks Association’s Grants (Grant

#s 43500-2715-FAR0016170 and 18484-2715) to Dr. Craig Stockwell and Sujan

Henkanaththegedara. All these grants were administered by Dr. Debra Hughson, Mojave

National Preserve. I also acknowledge ND EPSCoR SEED Grant (Grant # 43700-2715-

FAR0017552) to Dr. Craig Stockwell. In addition, I was able to secure funding through NDSU

Environmental and Conservation Sciences Graduate Program for a start-up fellowship (2006) and a research associate position during the completion of my dissertation writing (2011-2012),

NDSU Department of Biological Sciences for a teaching assistantship (2007), NDSU Graduate

School for the Dissertation Fellowship (2010-2011), and Desert Legacy Fund-California Desert

Research Program at the Community Foundation for field work. This work has been conducted under National Park Service permit # MOJA-2006-SCI-0014, U.S. Fish and Wildlife Service permit # TE126141-0.22 and NDSU Institutional Animal Care and Use Committee (IACUC) protocol # A0902.

Last, but by no means least, I like to offer appreciation and heartiest gratitude to my friends, parents, in-laws and family. My parents, Walter and Thilaka Henkanaththegedara, secured the best education for me with their love and guidance. My in-laws, Kiri Banda and

Chandra Herath, have been strength to our lives in many ways. Our good family friends, De

Saram family, Fernando family, Wijetunga family, Samaraweera family and Dr. Asoka

Marasinghe proved that they are “friends-in-deed” by shadowing us in both good times and bad.

Over the course of six years of my journey, my wife, Bodini Herath, together with our children

Mihin and Sanuthi Henkanaththegedara have been my enduring source of love, strength, and encouragement. They have always provided a “good reason” to continue my research and other academic achievements.

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DEDICATION

This Dissertation is Dedicated to

My parents, Walter and Thilaka Henkanaththegedara

My in-laws, Kiri Banda and Chandra Herath

My wife, Bodini Herath

And

Our children, Mihin and Sanuthi Henkanaththegedara

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TABLE OF CONTENTS

ABSTRACT……………………………………………………………………………………...iii

ACKNOWLEDGEMENTS…………..………………………………………………………...... v

DEDICATION...………………………………………………………………………………...viii

LIST OF TABLES.………………………………………….………………………………….xiii

LIST OF FIGURES.…………………………………………..………………………………...xiv

LIST OF APPENDIX TABLES …………………………………………………….…………xvii

LIST OF APPENDIX FIGURES ……………………………………………………..………..xix

CHAPTER 1. GENERAL INTRODUCTION.…………………………………………………...1

Ecological Complexity of Non-native Species Impacts…………………….…………….3

Natural History of Mohave Tui Chub……….…………………………………...……….6

Life History of Mohave Tui Chub………………………………………………..8

Population Dynamics of Mohave Tui Chub…………………………….……….11

Habitat Ecology of Mohave Tui Chub…………………………………………...11

Organization of Dissertation……………..……………….…………………………...…12

Literature Cited...………………………………………………………………………...13

CHAPTER 2. BEYOND THE DOGMA OF NON-NATIVE SPECIES: RECIPROCAL PREDATION MEDIATES CO-EXISTENCE OF NATIVE AND NON-NATIVE FISH……..21

Abstract……………………………………………..……………………………………21

Introduction………………………………………………………………………………22

Methods…………………………………..………………………………………………25

Experimental Setup……………………...……………………………………….25

Mesocosm Sampling……………………...……………………………………...27

Fish Measurements………...…………………………………………………….27

TABLE OF CONTENTS (continued)

Data Analysis……...……………………………………………………………..28

Results..…………….………………………………………………………………….…30

Mesocosm Conditions……………..……………………………….…………….30

Fish Survival…………………...………………………………………………...30

Mosquitofish Size……………………………………...………………………...32

Discussion………………………………………………………………………………..36

Literature Cited………………………………...………………………………………...39

CHAPTER 3. THE ROLE OF GAPE-LIMITATION IN INTRAGUILD PREDATION BETWEEN NATIVE AND NON-NATIVE FISH………………………………………….…..46

Abstract……………………………………………..……………………………………46

Introduction………………………………………………………………………………47

Methods…………………………………..………………………………………………49

Laboratory Predation Experiments………………...…….………..………….….49

Statistical Analysis...……………………………………………………...……...53

Vulnerability Modeling…………………………………………………………..54

Results..…………….………………………………………………………………….…56

Laboratory Predation Experiments...……………………...……….…………….56

Vulnerability Modeling...………………………………………………………...57

Discussion………………………………………………………………………………..60

Literature Cited……………………………..…………………………………………....65

CHAPTER 4. CONSERVATION TRANSLOCATIONS BENEFIT PROTECTED FISH, BUT MAY IMPACT ENDEMIC INVERTEBRATES..…………………………..……….…...70

Abstract……………………………………………..……………………………………70

TABLE OF CONTENTS (continued)

Introduction………………………………………………………………………………71

Methods…………………………………..………………………………………………74

Study System……………...…….…………………………………………...... 74

Experimental Setup..…………………………………...………………………...76

Sampling and Diversity Analysis…...………………………………………..…..78

Fish Diet Analysis……………………………..…………………………………79

Statistical Analysis…………………………………………...…………………..79

Results..…………….………………………………………………………………….…81

Discussion………………………………………………………………………………..88

Literature Cited…………………………………………………………………………..92

CHAPTER 5. GENERAL CONCLUSIONS...…………………………….…………………..100

Literature Cited…………………………………………………………………..……..102

APPENDIX A. LIFE HISTORY OF ENDANGERED MOHAVE TUI CHUB ……...………104

Background……………………………………………………………………………..104

Fish Sampling………………………...………………………………………………...104

Fish Age Structure………………………………………………………..…………….105

Reproductive Biology……………………………………………………………...…...109

Fish Diet………………………………………………………………………………...113

Literature Cited……………………………………………………...……………….. ..119

APPENDIX B. MONITORING THE CONSERVATION STATUS OF ENDANGERED MOHAVE TUI CHUB ……………………………………………………..122

Background……………………………………………………………………………..122

Methods………………………………………………………………………………...123

TABLE OF CONTENTS (continued)

Mark-recapture Methods………………………………………………………..123

Depletion Method.……………………………………………………………...124

Population Density and Structure………………………………...…………….126

Fish Condition………………………………………………………………….126

Results and Discussion……………...………………………………………………….127

MC Spring………………………………………………………………………127

Lake Tuendae…………………………………………………………………...134

Camp Cady……………………………………………………………………..135

China Lake……………………………………………………………………...140

Management Implications………………………………………………………………141

Literature Cited………………………………………………………………...……... .142

APPENDIX C.WATER QUALITY DATA…………..………………………………………..147

APPENDIX D. AQUATIC INVERTEBRATE DATA…………….…………………………..184

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LIST OF TABLES

Table Page

2.1 ANOVA summary table for water quality variations in mesocosms……………………31

3.1 Size of Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) utilized for predation experiments…………………………….……52

3.2 Size of Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) utilized for vulnerability modeling………………………..………..55

3.3 Size-dependent impacts of western mosquitofish, Gambusia affinis and eastern mosquitofish, G. holbrooki (indicated with †) on native fish species. Approach code: ME = mesocosm experiments, FO = field observations, LE = laboratory experiments, FE = field experiments, FS = field surveys……………………….………63

4.1 The final invertebrate densities in small (volume ~ 1.2 m3) and large (volume ~ 2.6 m3) tanks used for fishless control treatment. The averages were tested with Wilcoxon rank sum test for any significant differences.…………………………….…77

4.2 Akaikie Information Criteria with the small sample size correction on six candidate models used to model scores from a two-dimensional NMDS ordination. Abbreviations are MF = mosquitofish, MTC = Mohave tui chub, Fish/No Fish = presence or absence of fish, Total Fish = counts of fish present in experimental tanks, and Age Structure = a four parameter model where MF and MTC are further divided into adults and larval fish with counts used as predictors……………………………….83

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LIST OF FIGURES

Figure Page

1.1 Fish species introductions to the United States (Sources: Lachner et al. 1970; Courtenay et al. 1984; Benson 2000 and USGS-NAS 2009). Grey bars represent the exotic fish species which were introduced from the areas beyond geographical boundaries of the United States and the black bars represent the non-native species introduced within the geographic boundaries of the United States.…………………………….……………...... 2

1.2 Mohave tui chub (Siphateles bicolor mohavensis); an adult male from Lake Tuendae (Illustrated by Sujan Henkanaththegedara). ………………………………………………7

1.3 Current distribution of Mohave tui chub (Siphateles bicolor mohavensis) within San Bernardino County, California (Map by Justin Fisher)…………………………………...9

1.4 Extant populations of Mohave tui chub (Siphateles bicolor mohavensis) and its translocation history (Photos: Sujan Henkanaththegedara)……………………………...10

2.1 Components of 320 gallon tank set up used for mesocosm experiment; (A) a schematic cross section of a tank; (B) the tank set up in the field (Photo: Sujan Henkanaththegedara)……………………….……………………………………..29

2.2 Mohave tui chub total (a) and per capita (b) recruitment in the presence (sympatric; MTC + WMF) and absence (allopatric; MTC) of mosquitofish is shown. Error bars represent 1+/- SE………………………………….……………………………………..33

2.3 Average mosquitofish survival for adult male (a), adult female (b), juveniles (c), and per capita mosquitofish recruitment (d) in the presence (sympatric; MTC + WMF) and absence (allopatric; WMF) of Mohave tui chubs. Error bars represent 1+/- SE…………………………………………………………………………………...34

2.4 The size of surviving female mosquitofish in the presence (sympatric; MTC + WMF) and absence (allopatric; WMF) of Mohave tui chubs in terms of (a) body mass, and (b) total length), and (c) body depth. Error bars represent 1+/- SE……………….…....35

3.1 Body depth measurements of a Mohave tui chub larvae (Siphateles bicolor mohavensis) (A), a mature male (B) and a pregnant female (C) of western mosquitofish (Gambusia affinis)………………………………………………………...51

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LIST OF FIGURES (continued)

3.2 Kaplan-Meier estimates of proportional survival of prey during predation trials for (A) adult western mosquitofish (Gambusia affinis) prey with adult Mohave tui chub (Siphateles bicolor mohavensis) as predators and (B) Mohave tui chub larval prey with adult western mosquitofish as predator. Solid lines indicate Kaplan-Meier proportional survival function and dashed lines indicate 95% confidence intervals. Black and grey lines indicate the treatments with male and female mosquitofish respectively……………...…………………………………………………………….…58

3.3 Relative vulnerability (lines) of (A) mosquitofish (Gambusia affinis) prey under adult Mohave tui chub (Siphateles bicolor mohavensis) predation and (B) Mohave tui chub larval prey under adult mosquitofish predation. Frequency distribution of body depths of mosquitofish (A) are indicated with vertical bars and were constructed based on both male (n = 79) and female (n = 90) mosquitofish collected from Lake Tuendae in March-May 2009. The dark gray bars represent the portion of female mosquitofish size distribution overlapped with male mosquitofish size distribution……………………………………………….…………..59

4.1 The mean heterogeneity (Shannon-Wiener Index, H’) of aquatic invertebrate 2 diversity was significantly differed among treatments (X 3=25.56; p < 0.001). Treatment codes: MTC+MF = sympatric fish, MF only = allopatric mosquitofish, MTC only = allopatric tui chubs, and NONE = fishless control. Error bars are one standard error. Bars with different letters are significantly different at p = 0.05………………………………………………………………………………….84

4.2 Differences in mean density of major invertebrate taxa among treatments. 2 Significant differences of mean densities were observed for Nauplii (X 3 = 14.75; 2 2 p < 0.01), Cladocera (X 3 = 31.93; p < 0.05), Calanoid copepods (X 3 = 12.75; 2 p < 0.01), Cyclopid copepods (X 3 = 10.61; p < 0.05), and Chironomid larvae 2 (X 3 = 7.83; p < 0.05). Treatment codes: MTC+MF = sympatric fish, MF only = allopatric mosquitofish, MTC only = allopatric tui chubs, and NONE = fishless control. Error bars are one standard error. Bars with different letters are significantly different at p = 0.05. A* indicates marginal significance at p = 0.055...... ….…85

4.3 Nonmetric multidimensional scaling plot where points represent experimental units from treatments: Mohave tui chub only (■), mosquito fish only (○), both Mohave tui chub and mosquite fish (×), and no fish ( ). Site scores were relativized by the maximum and vectors represent the Pearson Correlation Coefficients for each taxa included in the ordination. The goodness of fit measure (R2) is for the relationship between the modeled distance matrix and the actual distance matrix. The NMDS was performed on maximum relativized taxa counts and used the Bray Curtis distance measure…………………………………………………………………………….…….86

LIST OF FIGURES (continued)

4.4 The distribution of various invertebrate food items in the guts of tui chub and mosquitofish (n = 30 each). Percentage occurrence (A), average number of invertebrates (B), and average number of invertebrates adjusted for fish biomass (C). Dark grey and black represent Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis), respectively. Error bars are one standard error. Significance level: * p < 0.05, ** p <0.01, *** p < 0.001………………….……………………………………………………...….87

4.5 Percentage composition of various invertebrate food items in the guts of Mohave tui chub (A) and mosquitofish (B)……………………………..……………………………88

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LIST OF APPENDIX TABLES

Table Page

A.1 Size of Mohave tui chubs (Siphateles bicolor mohavensis) used for life history descriptions in 2008. SE represents one standard error. …………………….……...….105

A.2 Heterogeneity and evenness of food items of Mohave tui chubs (Siphateles bicolor mohavensis) from four populations. Total N indicates the total number of individual food items in pooled gut samples (24 for MC Spring and 30 each for the rest) excluding unidentifiable insect parts and plant matter. Heterogeneity was measured in terms of Shannon-Weiner index (H’) and number of equally common species (N1) while evenness was measured using Simpson’s measure of evenness (E1/D)…….118

A.3 Food niche overlap between Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) at Lake Tuendae……………………………119

B.1 Details of the Mohave tui chub sampling (Siphateles bicolor mohavensis): dates, methods, traps used and trapping sessions……………………………………………...125

B.2 Details of the traps used to sample Mohave tui chub (Siphateles bicolor mohavensis)……………………………………………………………………………..125

B.3 Estimated total population size of Mohave tui chubs (Siphateles bicolor mohavensis) for MC Spring (Leslie regression model: Leslie and Davis 1939) and breeding population sizes for Lake Tuendae, Camp Cady-Bud’s Pond and China Lake-North Channel (Schumacher-Eschmeyer method; Schumacher and Eschmeyer 1943). The number of Lake Tuendae fish removed from the population for field experiments is shown in the last column…………………………………………………………….….128

B.4 TL (mm) of Mohave tui chub (Siphateles bicolor mohavensis) sampled across 4 habitats and 5 years. Sample size depicts total population size for MC Spring and number of fish handled during mark-recapture sessions for other habitats………...…..129

B.5 Population density of Mohave tui chub (Siphateles bicolor mohavensis) for MC Spring, Lake Tuendae, Camp Cady-Bud’s Pond, and China Lake-North Channel. Density and confidence intervals C.I. were estimated by dividing the total/estimated population size by the approximate volume of the habitat…………….……………….131

B.6 Fulton’s condition factor (C) of Mohave tui chub (Siphateles bicolor mohavensis) sampled across 4 habitats and 4 years. MC Spring values are based on the data collected from the total population while values for other populations are based on the data collected for “breeding” population (fish > 70 mm TL)………………………132

B.7 A comparison of population estimates of Mohave tui chub (Siphateles bicolor mohavensis) conducted at Lake Tuendae………………………………………………137

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LIST OF APPENDIX TABLES (continued)

C.1 MC Spring water quality data for 2007………………………………………………...147

C.2 Lake Tuendae water quality data for 2007……………………………………………..150

C.3 MC Spring water quality data for 2008………………………………………………...165

C.4 Lake Tuendae water quality data for 2008……………………………………………..167

C.5 MC Spring water quality data for 2009………………………………………………...177

C.6 Lake Tuendae water quality data for 2009……………………………………………..178

D.1. MC Spring aquatic invertebrate data for 2007 (number/L)….…………………………184

D.2. Lake Tuendae aquatic invertebrate data for 2007 (number/L)…………………………187

D.3. MC Spring aquatic invertebrate data for 2008 (number/L)….…………………………197

D.4. Lake Tuendae aquatic invertebrate data for 2008 (number/L)…………………………199

D.5. MC Spring aquatic invertebrate data for 2009 (number/L).……………………………206

D.6. Lake Tuendae aquatic invertebrate data for 2009 (number/L)…………………………207

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LIST OF APPENDIX FIGURES

Figure Page

A.1 Annual growth rings visible on an operculum of Mohave tui chub (Siphateles bicolor mohavensis). Insert shows the full operculum with the magnified area highlighted (Photo: Sujan Henkanaththegedara)……………………………………………………106

A.2 Age bias plot of Mohave tui chub (Siphateles bicolor mohavensis) for ages determined from scales (A) and opercula (B) compared to otolith ages. Dotted line indicates the theoretical 1:1 agreement line of age estimates………………………………………...107

A.3 Frequency of Mohave tui chub (Siphateles bicolor mohavensis) age based on opercula from Lake Tuendae (N = 29), MC Spring (N = 24) and Camp Cady (N = 30)………...108

A.4 Tubercle formation on an adult male Mohave tui chub (Siphateles bicolor mohavensis) from Lake Tuendae. Also note the dorsal hump (Photo: Sujan Henkanaththegedara)…………………………………………………………………...110

A.5 Variations of Gonado-somatic Index (GSI) of Mohave tui chubs (Siphateles bicolor mohavensis) across sex and habitats. Error bars represent ± 1 SE Numbers above bars represent the sample size for each category……………………………………….111

A.6 Correlations of fecundity with body size (A) and typical egg mass (B) of female Mohave tui chub (Siphateles bicolor mohavensis). Different symbols represent different populations of tui chub………………………………………………………..112

A.7 Percentage occurrence of major food items in Mohave tui chub (Siphateles bicolor mohavensis) guts among four populations……………………………………………...116

A.8 Percentage composition of major food items in Mohave tui chub (Siphateles bicolor mohavensis) guts among four populations……………………………………………...117

B.1 Percentage length frequency distribution of MC Spring Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2005-2009. Arrows indicate 2005 YOY cohort. MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game……………………………………………….…………130

B.2 Fluctuations of Young-Adult Ratio (YAR) of Mohave tui chub (Siphateles bicolor mohavensis) at MC Spring from 2005-2009. MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game………………………...131

B.3 Artificial cover suspended along the periphery of MC Spring (A) may have helped the survival of developing Mohave tui chub (Siphateles bicolor mohavensis) larvae and subsequent recruitment (B). Arrows indicate developing chub larvae (Photos: Sujan Henkanaththegedara)…………………………………………………………….133

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LIST OF APPENDIX FIGURES (continued)

B.4 Percentage length frequency distribution of Lake Tuendae Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2007-2009………………138

B.5 Percentage length frequency distribution of Camp Cady Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2007-2009…………………………..139

B.6 Percentage length frequency distribution of China Lake-North Channel Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2008………………141

CHAPTER 1. GENERAL INTRODUCTION

Introduced species, together with habitat loss, play a major role in population declines and biodiversity loss (Diamond 1989; Wilcove et al. 1998; Mack et al. 2000). For example, the establishment of non-native fish species has been associated with population declines in a variety of native aquatic organisms (Deacon et al. 1964; Courtenay and Meffe 1989; Kats and Ferrer

2003; Stockwell and Henkanaththegedara 2011). Hundreds of exotic fish species have been introduced to the United States from various countries since early European colonization

(Courtenay and Stauffer 1984; Moyle 1986; Gido and Brown 1999; Figure 1.1). A majority of these fish introductions were deliberate introductions for reasons such as sport fishing, farming for food, aquarium trade, and bio-control programs (Courtenay and Stauffer 1984; Fuller et al.

1999). In addition, non-native species were unintentionally introduced via the release of ship ballast water (Ricciardi and Maclsaac 2000) and accidental escapes from aquaculture facilities

(Courtenay and Stauffer 1984). Furthermore, many protected fish species have been introduced beyond their native historic range (Benson 2000) and these non-native species also pose threats to native aquatic species (Figure 1.1).

Although native to the United States, mosquitofish (Gambusia affinis and G. holbrooki) have been widely introduced to other parts of the United States and and many other countries to control mosquito-borne diseases (Krumholz 1948; Pyke 2008). Despite its presumed mosquito control ability, detrimental impacts of mosquitofish on other aquatic organisms are well documented (Courtenay and Meffe 1989; Pyke 2008; Stockwell and Henkanaththegedara 2011).

Unfortunately, both species have become invasive, and western mosquitofish (G. affinis) was recently listed among the “worst 100 invasive species” posing significant threats to native aquatic organisms (Lowe et al. 2000) typically via competition and/or predation (Hurlbert et al.

1972; Courtenay and Meffe 1989). For example, mosquitofish preyed on zooplankton and aquatic macro-invertebrates reducing their densities (Hurlbert et al. 1972; Angeler et al. 2002).

Mosquitofish also caused reduced growth and survival of fish species (Meffe 1985; Mills et al.

2004; Rogowski and Stockwell 2006) and amphibians (Kats and Ferrer 2003).

450

400 exotic non-native 350

300

250

200

150 Number of species Number 100 50

1970 1984 2000 2009 Time (year)

Figure 1.1. Fish species introductions to the United States (Sources: Lachner et al. 1970; Courtenay et al. 1984; Benson 2000 and USGS-NAS 2009). Grey bars represent the exotic fish species which were introduced from the areas beyond geographical boundaries of the United States and the black bars represent the non-native species introduced within the geographic boundaries of the United States.

Western mosquitofish were first noted in Lake Tuendae, California, habitat for one of the five populations of endangered Mohave tui chub (Siphateles bicolor mohavensis), in 2001 as a result of an unknown, illegal introduction (Steve Parmenter personal communication). These

2 observations coincided with Lake Tuendae shifting to a turbid state in the fall of 2002 (Hughson and Woo 2004; Rob Fulton Personal Communication). This led managers to hold a workshop to revisit the Mohave tui chub recovery plan (U.S. Fish and Wildlife Service 1984) and to develop recommendations for future management actions (Hughson and Woo 2004). Two important research needs resulted from this workshop are;

1. Identification and reduction of threats to extant and future populations of Mohave tui

chub

2. Research to understand Mohave tui chub ecology and habitat requirements

Towards these goals, I evaluated the potential impacts of western mosquitofish on both the Mohave tui chub and associated invertebrate communities using field mesocosm experiments and laboratory predation trials. In addition, I studied the life history and population dynamics of four Mohave tui chub populations.

Ecological Complexity of Non-native Species Impacts

The negative impacts of non-native species on native species and ecosystems have been a major focus of contemporary ecology, ever since the publication of “The Ecology of Invasions by Animals and Plants” by Charles Elton (Elton 1958). Accelerated human-mediated dispersion of organisms beyond natural background levels has led to the homogenization of biota throughout the world (Elton 1958; Lodge 1993a; McKinney and Lockwood 2001). The emerging sub-discipline of invasion biology has focused on documenting the negative impacts of invaders on native species or ecosystems evaluating and determining biotic characteristics that facilitate invasion of new habitats, as well as the characteristics that pre-dispose certain

3 ecosystems to invasions (Elton 1958; Baker and Stebbins 1965; Lodge 1993b; Sax et al. 2005;

Davis 2009).

Invaded ecosystems with multiple, established, non-native organisms have become the norm rather than the exception (Bull and Courchamp 2009). In most ecosystems, invasive species often assume the ecological role of some native species, which in turn creates complex interactions among native and invading species (Zavaleta et al. 2001). Therefore, control or eradication of invasive species can result in unforeseen detrimental impacts (Zavaleta et al. 2001;

Bull and Courchamp 2009). For example, removal of an invasive predator which co-occurs with invasive and native prey could result in mesopredator release, potentially increasing predation both on native species of conservation priority (Karl and Best 1982; Fitzgerald 1988). Similarly, eradication of invasive herbivores in order to restore native flora could promote the spread of an invasive plant (Kessler 2001). Therefore it is critical to understand the complex ecological interactions between native and invasive organisms before management actions are taken which may inadvertently harm native species (Courchamp et al. 2003; Bull and Courchamp 2009).

Managers are particularly focused on containing the invasion of particular species that have been reputed to negatively impact native species. Such is the case with mosquitofish (G. affinis and G. holbrooki) which have negatively impacted native aquatic invertebrates, fish and amphibians mainly by predation and competition (Courtenay and Meffe 1989; Pyke 2008;

Stockwell and Henkanaththegedara 2011). Although mosquitofish predation on various developmental stages of native fish is well established (Meffe 1985; Belk and Lydeard 1994;

Mills et al. 2004; Rogowski and Stockwell 2006), little work has been conducted to evaluate any potential impacts by native species on invasive mosquitofish, which could potentially lead to co- persistence of native species with non-natives. I used both field mesocosm experiments and

4 laboratory predation trials to study reciprocal species interactions between endangered desert fish, Mohave tui chub and invasive western mosquitofish, and impacts of recently established fish populations on aquatic invertebrates (see Chapters 2, 3 and 4).

The initial research focused only on the impacts of western mosquitofish on Mohave tui chub, ignoring the possible effects of tui chub on mosquitofish (Stockwell and

Henkanaththegedara 2011). That work produced an unexpected observation that tui chubs apparently prey on adult mosquitofish, leading to the work reported in Chapter 2. Chapter 2 reports the results of a mesocosm experiment designed to evaluate intraguild predation (IGP) between native Mohave tui chub and non-native western mosquitofish.

In order to further explore IGP between tui chubs and mosquitofish, laboratory experiments were designed with predation trials using various developmental stages of Mohave tui chub and western mosquitofish. Because mosquitofish are sexually dimorphic, sex specific differences in gape-size limitation in mosquitofish were tested. The results of these experiments, together with vulnerability modeling, allowed me to evaluate the role of predator gape-limitation in IGP, which is reported in Chapter 3.

Additionally, I explored the impacts of recently established fish populations on aquatic invertebrates in desert springs, which is another aspect of the complex interactions between native and non-native species in desert ecosystems. Both Mohave tui chubs and western mosquitofish are non-native to desert springs, which harbor unique and endemic invertebrate communities. Using filed mesocosm experiments, I explored the potential impacts of native fish transplants and introduction of invasive fish on aquatic invertebrate community structure in fishless desert water bodies. This work is reported in Chapter 4.

Concurrent with this experimental work, my research also involved considerable descriptive work to better characterize life history and population dynamics of the four Mohave tui chub populations at Lake Tuendae, MC Spring, Camp Cady and China Lake. I have summarized these results in subsequent appendices together with additional descriptive work on habitat characteristics of Lake Tuendae and MC Spring.

Natural History of Mohave Tui Chub

Almost every isolated or partially isolated drainage system in California, Nevada and

Oregon supports at least one distinctive form of tui chub (Moyle 2002). These populations are classified as sub-species of the Siphateles bicolor species complex, as is the case with the

Mohave tui chub (S. b. mohavensis; Figure 1.2). However, others have suggested that Mohave tui chub is sufficiently distinct to warrant specific status (Moyle 2002; Harris 1991). Although

Snyder (1918) originally described Mohave tui chub from the Mojave River as a valid species,

Miller (1973) placed it within the Siphateles bicolor species complex and downgraded its taxonomic status to a subspecies. However, there are multiple lines of morphological and molecular evidence to support the uniqueness of Mohave tui chub as a valid species (Uyeno

1966; Harris 1994; May et al. 1997; Figure 1.2). Uyeno (1966) found two osteological characters that distinguish Mohave tui chub from S. b. obesus. In addition, May et al. (1997) reported a fixed differences between Mohave tui chub compared to other tui chubs (Lahontan and Owens basins) at one allozyme locus (Galactosaminidase) and an AFLP allele were reported (May et al.

1997). Furthermore, Harris (1994) found that six nucleotide positions of mt-DNA (cytochrome b) were autapomorphies for Mohave tui chub and phylogenetic analysis revealed Mohave tui chub to be the sister species to all remaining tui chub taxa.

10 mm

Figure 1.2. Mohave tui chub (Siphateles bicolor mohavensis); an adult male from Lake Tuendae (Illustrated by Sujan Henkanaththegedara).

The Mohave tui chub is a California state, and federally, protected endangered minnow

(Family Cyprinidae) endemic to the Mojave River drainage in southern California (U.S. Fish and

Wildlife Service 1984). Mohave tui chubs once occurred in the deep pools and slow moving areas of the main-stream Mojave River (Snyder 1918). However, river populations were extirpated by late the 1960s (Miller 1969) due to a combination of threats, including presumed hybridization with introduced arroyo chub (Gila orcutti), a severe flash flood in 1938 (Hubbs and Miller 1943), impacts of introduced brown bullhead (Ameiurus nebulosus), and habitat modification and degradation (Thompson 1929). A relict population was discovered near Soda

Dry Lake (Miller 1938), a water body that approximates historic descriptions of the original spring-fed pool located at the site of Lake Tuendae (Thompson 1929; Miller 1938) before the basin was expanded to create the current lake in early 1940s (Turner and Liu 1976).

Mohave tui chub populations were subsequently established by extensive translocation efforts in the 1960s and 1970s (Miller 1968; St. Amant and Sasaki 1971). Fish were introduced from Lake Tuendae to a variety of sites, but only three populations persisted at the following habitats: (1) Bud’s Pond at Camp Cady State Wildlife Area, (2) Seep system in China Lake

Naval Air Weapons Station, Ridgecrest, and (3) Deppe Pond/Tui Slough system at Lewis Center for Academic Excellence, Victorville established in October, 2008 (Figure 1.3 and 1.4).

Life History of Mohave Tui Chub

The ecology and life history characteristics of Mohave tui chub are poorly documented.

Vicker (1973) studied some aspects of life history of Mohave tui chub (S. b. mohavensis) focusing on age and growth, diet, and reproductive biology of Lake Tuendae population. In addition, Taylor and McGriff (1985) reported age and growth of tui chubs inhabiting Lake

Tuendae and Three-bats pond (extirpated) and Feldmeth et al. (1985) reported some preliminary studies on reproduction, diet, parasites and environmental tolerance of tui chubs from China

Lake. However, none of these studies compared the life history variation within and among the various Mohave tui chub populations. Therefore, I conducted a comparative assessment of the four extant populations of Mohave tui chubs focusing on age structure, reproductive biology, population dynamics and diet (see Appendix A).

Figure 1.3. Current distribution of Mohave tui chub les bicolor mohavensis) within San Bernardino County, California (Map by Justin Fisher).

Figure 1.4. Extant populations of Mohave tui chub (Siphateles bicolor mohavensis) and its translocation history (Photos: Sujan Henkanaththegedara).

Population Dynamics of Mohave Tui Chub

Although the Mohave tui chub recovery plan (U.S. Fish and Wildlife Service 1984) warrants annual population census, there is no active, continuous, long-term population monitoring program. Sporadic work suggests that there is a considerable seasonal variation in

Mohave tui chub population size (Vicker 1973; Taylor 1982; Garron 2006). A lack of methodological consistency among these studies prohibits direct comparison of population size or drawing useful conclusions about population dynamic with confidence. In conjunction with the California Department of Fish and Game, I have developed protocols to conduct annual population estimates of Mohave tui chub for Lake Tuandae and MC Spring. Population estimates were conducted at Lake Tuendae and Camp Cady using mark-recapture methods from 2007-

2009 and at MC Spring using the depletion method from 2006-2009. Additional sampling was conducted on the North Channel segment of the China Lake population in 2008 (see Appendix

B).

Habitat Ecology of Mohave Tui Chub

A sound understanding of habitat quality and requirements is an essential component of the management of endangered species (Noss et al. 1997). In fact, all existing Mohave tui chub populations occupy highly altered habitats and one historic population (i.e. Three-bats pond) was extirpated, presumably due to poor water quality (U.S. Fish and Wildlife service 1984; Hughson and Woo 2004). Therefore, the Mohave tui chub recovery plan (U.S. Fish and Wildlife service

1984) and management action plan (Hughson and Woo 2004) both call for frequent water quality analysis in all Mohave tui chub habitats. Archbold (1994) developed a habitat evaluation scheme for Mohave tui chubs focusing on water quality parameters to evaluate existing habitat quality and to assess the habitat suitability for future refugia. However, this study did not include

11 zooplankton community structure, which is very important in understanding trophic relationships and nutrient cycling in the system (Carpenter et al. 1985, 1987). I studied physico-chemical characteristics of water and zooplankton communities in Mohave tui chub habitats, focusing on

Lake Tuendae and MC Spring (see Appendix C).

Organization of Dissertation

My dissertation is intended provide experimental evidence on ecological complexity of non-native species impacts on native species using western mosquitofish and Mohave tui chub as model organisms. It also provides key information components and guidelines required for the recovery and down-listing of endangered Mohave tui chub. Information and guidelines provided on two major aspects of Mohave tui chub recovery plan and management action plan; 1) assessment of potential impacts of western mosquitofish on Mohave tui chub, and 2) Mohave tui chub life history descriptions and ecology (U.S. Fish and Wildlife Service 1984; Hughson and

Woo 2004).

The dissertation is composed of five chapters including this general introduction and last chapter on general conclusions. The Chapter 2 was formatted for submission to the journal

Conservation Biology and focuses on reciprocal predation between invasive western mosquitofish (G. affinis) and endangered Mohave tui chub (S. b. mohavensis) based on field mesocosm experiments. Chapter 3 which was written for submission to the journal Oecologia, examines the role of predator gape-limitation in intraguild predation between these two fish species. Chapter 4 was written for submission to the journal Diversity and Distributions and focuses on the impacts of recently established fish populations on endemic spring invertebrates. I conclude my dissertation with Chapter 5, discussing the implications of my research findings on

12 complex ecological interactions between non-native and native organisms, in broader sense, and the conservation management of endangered Mohave tui chub, in a narrow sense. In addition, I included four appendices on life history, population monitoring and habitat monitoring of endangered Mohave tui chub. This novel information may fill gaps in these particular areas and may help in planning conservation actions aimed at the down-listing and delisting of this endangered fish species.

Literature Cited

Angeler, D.G., M. Álvarez-Cobelas, S. Sánchez-Carrillo and M.A. Rodrigo. 2002. Assessment of

exotic fish impacts on water quality and zooplankton in a degraded semi-arid floodplain

wetland. Aquatic Sciences-research Across Boundaries 64:76-86.

Archbold, C. A. 1994. Habitat evaluation for the Mohave tui chub (Gila bicolor mohavensis).

Master’s thesis. California State University Fullerton.

Baker, H.G. and G.L Stebbins (editors). 1965. The genetics of colonizing species. Academic

Press, New York.

Belk, M.C. and C. Lydeard. 1994. Effect of Gambusia holbrooki on a Similar-Sized, Syntopic

Poeciliid, Heterandria formosa: Competitor or Predator? Copeia 1994:296-302.

Benson, A.J. 2000. Documenting over a century of aquatic introductions in the United States.

Pp.1-31. In. Claudi, R. and J.H. Leach (editors). Nonindigenous freshwater organisms:

vectors, biology, biology and impacts. Lewis Publishers, CRC Press LLC, Florida.

Bull, L.S. and F. Courchamp. 2009. Management of interacting invasives: ecosystem

approaches. Pp. 232-247. In. Clout, M.N. and P.A. Williams (editors) Invasive species

management: A handbook of principles and techniques. Oxford University Press, New

York.

Carpenter, S. R., J. F. Kitchell, J.R. Hodgson. 1985. Cascading trophic interactions and lake

productivity: fish predation and herbivory can regulate lake ecosystems. Bioscience. 35:

643-639.

Carpenter, S. R., J. F. Kitchell, J.R. Hodgson, P.A. Cochran, J.J. Elser, M.M. Elser, D.M. Lodge,

D. Kretchmer, X. He and C.N. von Ende. 1987. Regulation of lake primary productivity

by food web structure. Ecology. 68:1863-1876.

Courchamp, F., J. Chapuis, and M. Pascal. 2003. Mammal invaders on islands: impact, control

and control impact. Biological Reviews 78:347–383.

Courtenay, W.R. Jr., D.A. Hensley, J.N. Taylor, and J.A. McCann. 1984. Distribution of exotic

fishes in the continental United States. Pp. 41-77. In. Courtenay, W.R. Jr. and J.R.

Stauffer (editors). Distribution, biology, and management of exotic fishes. The John

Hopkins University Press, Baltimore.

Courtenay, W.R. Jr. and G. K. Meffe. 1998. Small fishes in strange places: A Review of

introduced Poecillids. Pp. 319-333. In. G. K. Meffe and F. F. Snelson, Jr. (eds.), Ecology

and Evolution of livebearing fishes (Poecillidae). Prentice Hall, New Jersey, NJ, USA.

Courtenay, W.R. Jr. and J.R. Stauffer (editors). 1984. Distribution, biology, and management of

exotic fishes. The John Hopkins University Press, Baltimore.

Davis, M.A. 2009, Invasion Biology. Oxford University Press, Oxford.

Deacon, J.E., C. Hubbs and B.J. Zahuranec. 1964. Some effects of introduced fishes on the

native fish fauna of southern Nevada. Copeia 1964:384-388.

Diamond, J.M. 1989. The present, past and future of human-caused extinctions. Philosophical

Transactions of the Royal Society of London. Series B325:469-477.

Elton, C.S. 1958. The ecology of invasions by animals and plants. Methuen & Co., London.

Feldmeth, R., D. Soltz, L. McClanahan, J. Jones, and J. Irwin. 1985. Natural resources of the

Lark Seep system (china Lake, CA) with special emphasis on the Mohave chub (Gila

bicolor mohavensis). Proceedings of the Desert Fishes Council XIII-XV-B:356-358.

Fitzgerald, B.M. 1988. Diet of domestic cats and their impact on prey populations. Pp. 123-146.

In. Turner, D.C. (editor) The Domestic Cat: The biology of its behavior. Cambridge

University Press.

Fuller, P.L., L.G. Nico, and J.D. Williams. 1999. Non-indigenous fishes introduced into inland

waters of the United States. American Fisheries Society.

Garron, K.A. 2006. Population status of the endangered Mohave tui chub (Siphateles bicolor

mohavensis) at Lake Tuendae, Zzyzx, California. Masters Thesis, California State

University, Fullerton.

Gido, K.B. and J.H. Brown. 1999. Invasion of North American drainages by alien fish species.

Freshwater Biology 42:387-399.

Harris, P.M. 2001. Systematic studies on the genus Siphateles (Ostariophysi: Cyprinidae) from

western North America. Ph.D. Dissertation, Oregon State University.

Hubbs, C. L. and R. R. Miller. 1943. Mass hybridization between two genera of cyprinid fishes

in the Mohave Desert, California. Papers of the Michigan Academy of Science, Arts and

Letters. 28:343-378.

Hughson, D. and D. Woo. 2004. Report on a workshop to revisit the Mohave tui chub recovery

plan and a management action plan. National Park Service.

Hurlbert, S. H., J. Zedler and D. Fairbanks. 1972. Ecosystem alteration by mosquitofish

(Gambusia affinis) predation. Science. 175:639-641.

Karl, B.J., and H.A. Best. 1982. Feral cats on Stewart Island; their foods and their effects on

kakapo. New Zealand Journal of Zoology 9:287-294.

Kats, L.B. and R.P. Ferrer. 2003. Alien predators and amphibian declines: review of two decades

of science and the transition to conservation. Diversity & Distributions 9:99-110.

Kessler, C.C. 2001. Eradication of feral goats and pigs from Sarigan Island, Commonwealth of

the Northern Mariana Islands; methods and results. In. Clout, M. (editor). Eradication of

Islands Invasives: Practical Actions and Results Achieved, University of Auckland, New

Zealand.

Krumholz, L.A. 1948. Reproduction in the Western Mosquitofish, Gambusia affinis affinis

(Baird & Girard), and Its Use in Mosquito Control. Ecological Monographs 18:1-43.

Lachner, E.A., C.R. Robins, and W.R. Courtenay. 1970. Exotic fishes and other aquatic

organisms introduced into North America. Smithsonian Contributions to Zoology 59:1-

29.

Lodge, D.M. 1993a. Biological invasions: Lessons for ecology. Trends in Ecology and Evolution

8:133-137.

Lodge, D.M. 1993b. Species invasions and deletions: community effects and responses to

climate and habitat change. Pp.367-387. In. Kareiva, P.M., J.G. Kingsolver and R.B.

Huey (editors). Biotic interactions and global change. Sinauer Associates, Inc.,

Sunderland.

Lowe S., M. Browne, S. Boudjelas, M. De Poorter. 2000. 100 of the World’s Worst Invasive

Alien Species A selection from the Global Invasive Species Database. The Invasive

species Specialist Group (ISSG) a specialist group of the Species Survival Commission

(SSC) of the World Conservation Union (IUCN), Gland, Switzerland.

Mack, R.N., D. Simberloff, W. M. Lonsdale, H. Evans, M. Clout, and F. Bazzaz. 2000. Biotic

Invasions: Causes, Epidemiology, Global Consequences and Control. Ecological

Applications 10:689–710.

McKinney, M.L. and J.L. Lockwood. 2001. Biotic homogenization: a sequential and selective

process. Pp. 1-19. In. Lockwood, J.L. and M.L. McKinney (editors). Biotic

Homoginization. Springer.

May, B, J. Rodzen, and J. Agresti. 1997. Genetic purity and sub-specific status of the Mohave tui

chub. Final Report.

Meffe, G. K. 1985. Predation and species replacement in American southwestern fishes: a case

study. Southwest. Nature. 30:173-187.

Miller, R.R. 1938. Description of an isolated population of the freshwater minnow Siphateles

mohavensis from the Mohave River basin, California. Pomona College Journal of

Entomology and Zoology 30:65-67.

Miller, R.R. 1968. Records of some native freshwater fishes transplanted in to various waters of

California, Baja California and Nevada. Calif. Fish and Game. 54:170-179.

Miller, R.R. 1969. Conservation of fishes in the Death Valley system in California and Nevada.

Cal-Nevada Wildlife Transactions 1969:107-122.

Miller, R.R. 1973. Two new fishes, Gila bicolor snyderi and Catostomus fumeiventris, from the

Owens River basin, California. Occ. Pap. Mus. Zool. Univ. Michigan. 667:1-19.

Mills, D., R.B. Rader, M.C. Belk. 2004 Complex interactions between native and invasive fish:

the simultaneous effects of multiple negative interactions. Oecologia 141:713-721.

Moyle, P.B. 1986. Fish introductions into North America: patterns and ecological impacts. Pp.

27-43. In. Mooney, H.A. and J.A. Drake (editors). Ecology of biological invasions of

North America and Hawaii. Ecological studies 58. Springer-Verlag New York Inc.

Moyle, P.B. 2002. Inland fishes of California (revised and expanded), University of California

Press. Berkeley, California.

Noss, R.E., M.A. O’Connell and D.D. Murphy. 1997. The Science of Conservation Planning:

Habitat Conservation under the Endangered Species Act. World Wildlife Fund/Island

Press, Washington D.C.

Pyke, G.H. 2008. Plague Minnow or Mosquito Fish? A Review of the Biology and Impacts of

Introduced Gambusia Species. Annual Review of Ecology, Evolution, and Systematics

39:171-191.

Ricciardi, A. and H.J. Maclsaac. 2000. Recent mass invasion of the North American Great Lakes

by Ponto-Caspian species. Trends in Ecology and Evolution 15:62-65.

Rogowski D.L., C.A. Stockwell. 2006. Assessment of Potential Impacts of Exotic Species on

Populations of a Threatened Species, White Sands Pupfish, Cyprinodon tularosa.

Biological Invasions. 8:79-87.

Sax, D.F., J.J. Stachowicz and S.D. Gaines (editors). 2005. Species Invasions: Insights in to

ecology, evolution, and biogeography. Sinauer Associates, Inc. Publishers,

Massachusetts.

Snyder, J. 1918 The fishes of Mohave river, California. Proc. U.S. Nat. History Museum.

54:297-299.

St. Amant, J. A. & S. Sasaki. 1971. Progress report on reestablishment of the Mohave tui chub,

Gila bicolor mohavensis (Snyder), an endangered species. California Fish & Game.

57:307-308.

Stockwell, C.A. and S.M. Henkanaththegedara. 2011. Evolutionary Conservation Biology of

Poeciliids. In. Evan, J., A. Pilastro and I. Schlupp (editors). Ecology and Evolution of

Poeciliid Fishes. University of Chicago Press. Chicago.

Taylor, T. L. 1982. Population size and age and growth of Mohave tui chub at Fort Soda,

California. Draft final report to the Bureau of Land management in fulfillment letter

contract # CA-930-CTI-4.

Taylor, T.L. and D. McGriff. 1985. Age and growth of Mohave tui chub Gila bicolor mohavensis

from two ponds at Ft. Soda. Proceedings of the Desert Fishes Council XIII-XV-B:299-

302.

Thompson, D.G. 1929. The Mohave Desert region, California. Water-supply paper 578.

Geological Survey, U.S. Department of the Interior.

Turner, B.J. and R. K. Liu. 1976. The specific identity of the introduced pupfish at Zzyzx Spring,

California. Copeia 1976:211-212.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. U.S. Fish and Wildlife Service, Portland, OR.

U. S. Geological Survey (USGS). 2009. Non-indigenous Aquatic Species (USGS-NAS).

http://nas.er.usgs.gov/. Accessed April 2009.

Uyeno, T. 1966. Osteology and phylogeny of the American cyprinid fishes, allied to the genus

Gila. Ph.D. Dissertation, University of Michigan, Ann Arbor.

Vicker, C. E. 1973, Aspects of the life history of the Mohave tui chub Gila bicolor mohavensis

(Snyder) from Soda Lake California. Master’s Thesis, California State University

Fullerton.

Wilcove, D.S., D. Rothstein, J. Dubow, A. Phillips and E. Losos. 1998. Quantifying threats to

imperiled species in the United States: Assessing the relative importance of habitat

destruction, alien species, pollution, overexploitation, and diseases. Bioscience 48:607-

615.

Zavaleta, E.S., R.J. Hobbs, and H.A. Mooney. 2001. Viewing invasive species removal in a

whole-ecosystem context. Trends in Ecology and Evolution 16:454-459.

CHAPTER 2. BEYOND THE DOGMA OF NON-NATIVE SPECIES:

RECIPROCAL PREDATION MEDIATES CO-EXISTENCE OF NATIVE

AND NON-NATIVE FISH*

Submitted to Conservation Biology as: Sujan Henkanaththegedara1 and Craig Stockwell1.

Beyond the dogma of non-native species: reciprocal predation mediates co-existence of native and non-native fish.

1 Environmental and Conservation Sciences Graduate Program, Department of Biological

Sciences, North Dakota State University Dept. 2715, P.O. Box 6050, Fargo ND 58108-6050.

Abstract

Dogmatic views of non-native species as universally “bad” can constrain research objectives and options available to conservation practitioners. However, challenging such dogma can be important for understanding the circumstances under which native species may co- persist with non-native species which in turn can provide important insights on how best to manage altered systems. Here, we report a case of intraguild predation (IGP) as a mechanism facilitating co-persistence of an endangered species (Mohave tui chub, Siphateles bicolor mohavensis) with a non-native invasive species (western mosquitofish, Gambusia affinis). We established experimental sympatric and allopatric populations of Mohave tui chub and western mosquitofish to evaluate reciprocal trophic interactions between these two fish species.

* The material in this chapter was co-authored by Sujan Henkanaththegedara and Craig Stockwell. Henkanaththegedara and Stockwell conceived and designed the experiments. Henkanaththegedara performed the experiments and analyzed the data. Stockwell served as proofreader and checked the statistical analysis conducted by Henkanaththegedara.

Mosquitofish had a significant negative effect on Mohave tui chub recruitment (W = 142; P <

0.01). Reciprocally, tui chubs had a significant negative effect on survival of adult mosquitofish

(W=155.0; P<0.001) and juvenile production (W = 48.5; P < 0.001). Both male mosquitofish and small female mosquitofish had reduced survival in sympatry with tui chubs. Additionally, sympatric female mosquitofish survivors were significantly larger than female mosquitofish survivors in the allopatric populations, suggesting that large females were less vulnerable to predation by Mohave tui chub. These results collectively show size-structured IGP between these two fish species, probably due to gape-size limitation. Thus, IGP is an apparent mechanism facilitating co-persistence of these species. These findings provide more management options allowing managers to allocate resources to other threats and also will allow managers to consider habitats currently harboring mosquitofish as possible refuge sites for

Mohave tui chub, an option previously un-available. Our findings also provide a cautionary tale on how negative perceptions of non-native species can constrain research and management options.

Introduction

Conservation biology is inherently a normative science whereby human values can and should affect scientific process (Soule 1991; Lindenmayer and Hunter 2010). However, perceptions may constrain the questions conservation biologists ask as well as approaches taken to answer those questions. For example, dogmatic views of non-native species as universally

“bad” may constrain research objectives, interpretation of scientific experiments, and most importantly constrain options available to conservation practitioners. Unfortunately, such constraints may be very costly given the clear reality that most ecosystems already harbor or will

22 eventually harbor non-native species (Zavaleta et al. 2001; Sax et al. 2005; Bull and Courchamp

2009).

A recent debate has challenged the conventional dogmatic view of non-native species as universally “bad” (Davis et al. 2011; Lerdau and Wickham 2011; Lockwood et al. 2011;

Schlaepfer et al. 2011; Simberloff 2011) and has created an opportunity to re-evaluate how conservation biologists study and manage non-native species. One area of fruitful exploration is for scientists to study the interactions among native and non-native species (Courchamp and

Caut 2006; Roemer et al. 2002). Because ecological interactions among native and non-native species are often complex (Karl and Best 1982; Fitzgerald 1988; Bull and Courchamp 2009;

Ehrenfeld 2010), control or eradication of invasive species can have unexpected impacts on conservation target species (Courchamp and Caut 2006; Bull and Courchamp 2009). For example, removal of feral cats (Felis catus) released non-native rats (Rattus spp.) from cat predation, and thus increased rat predation on native bird species (Karl and Best 1982; Fitzgerald

1988). Similarly, Roemer et al. (2002) showed that removal of non-native pigs could indirectly increase predation pressure on the endangered Channel Island fox (Urocyon littoralis) by golden eagles (Aquila chrysaetos).

A mechanism that may facilitate co-persistence of native and non-native species is intraguild predation (IGP), whereby individuals of a single species act as prey, competitors, and/or predators, depending on their age and size (Polis et al. 1989; Polis and Holt 1992).

Intraguild predation has been reported in a variety of systems (Polis et al. 1989; Arim and

Marquet 2004) and IGP is likely to occur in systems involving native and non-native species, which interact via reciprocal predation (Bampfylde and Lewis 2007). For instance, introduced

23 alewives (Alosa pseudoharengus) preyed on the larvae of native walleye (Sander vitreus;

Brooking et al. 1998), and adult walleyes preyed on alewives (Schneider and Leach 1977).

This theoretical framework is likely to be important in cases where non-native species play key roles as predators and/or competitors. Such is the case for invasive western mosquitofish (Gambusia affinis), which has been labeled as one of the world’s “worst 100 invasive species” (Lowe et al. 2000) due to its impacts on native fishes, amphibians and invertebrates via predation and competition (Pyke 2008). Two pioneering papers (Deacon et al.

1964; Minckley and Deacon 1968) identified western mosquitofish as one of the major threats imperiling native desert fish of the south-western United States. A series of subsequent publications presented experimental data (Hurlbert et al. 1972; Meffe 1985; Mills et al. 2004;

Rogowski and Stockwell 2006) and anecdotal evidence (Arthington 1984; Galat and Robertson

1992) further cementing a negative perception of mosquitofish as reflected in their numerous derogatory monikers; “the fish destroyer”, “damnbusia” and “plague-minnow” (Myers 1965;

McCullough 1998; Pyke 2008).

Notably, this perception has affected the motivation for previous research and management actions including work conducted by our own research group (Rogowski and

Stockwell 2006; Stockwell and Henkanaththegedara 2011). The motivation for the current study was to evaluate the impacts of non-native western mosquitofish on the federally listed

Endangered Mohave tui chub (Siphateles bicolor mohavensis). The Mohave tui chub recovery plan lists mosquitofish presence as a threat to recovery, but little data were available to support this claim.

Our initial approach to this problem was to design a “removal” experiment to simulate how Mohave tui chub would perform if mosquitofish were eradicated. Thus, we consciously employed an explicit one-tailed design that included Mohave tui chub both in allopatry and sympatry with western mosquitofish. We reasoned that an additional treatment including mosquitofish in allopatry would have been a misallocation of critical experimental resources.

This dogmatically influenced design did not allow us to test the effects of Mohave tui chub on mosquitofish (Stockwell and Henkanaththegedara 2011). Much to our surprise, we found un- controlled evidence of such an effect at the conclusion of the experiment when we observed very low survivorship of mosquitofish adults – effectively our treatment died! Here, we report the results of a subsequent mesocosm experiment designed to evaluate IGP between invasive western mosquitofish and Endangered Mohave tui chub. We also discuss the importance of this experiment in understanding complex interactions between native and non-native taxa.

Methods

Experimental Setup

Thirty large circular mesocosms with a diameter of 1.8 m were employed to host experimental sympatric and allopatric populations of Mohave tui chub and western mosquitofish

(Figure 2.1). Mesocosms have been effectively used to evaluate the interactions between native and invasive species under semi-natural conditions (Belk and Lydeard 1994; Rincon et al. 2002;

Rogowski and Stockwell 2006). Mesocosms were deployed adjacent to Lake Tuendae (Desert

Studies Center, Zzyzx, CA) and filled with lake water filtered through 1.18 mm mesh to exclude larval fish. Mesocosms were filled to a depth of 55 cm (volume ~1.20 m3) to mimic the typical depth of habitats where mosquitofish co-occur with Mohave tui chub. Each tank was provided

25 with a constant aeration system, 3 linear meters of plastic “plants” to provide cover for fish larvae/juveniles and poultry fence to exclude avian predators.

The thirty mesocosms were randomly assigned to one of three treatments each with 10 replicates: allopatric Mohave tui chubs (MTC); allopatric western mosquitofish (WMF); and

Mohave tui chubs sympatric with western mosquitofish (MTC + WMF). Tanks were stocked with adult Mohave tui chubs and mosquitofish captured from Lake Tuendae using minnow traps and hand nets. Prior to stocking, tui chubs were anesthetized (MS-222 100 mg/L) and measured for total length (nearest 1 mm) and mass (nearest 0.1 g). Mosquitofish were not measured due to initial mortality associated with handling stress. Mesocosms receiving Mohave tui chubs (MTC and MTC+WMF) were each stocked with 8 adult Mohave tui chubs of typical size (80-120 mm).

Mesocosms receiving mosquitofish (WMF and MTC+WMF) were each stocked with 25 male and 50 female mosquitofish. Relative densities of the two species and the sex ratio of mosquitofish were chosen to reflect relative densities and sex ratios in Lake Tuendae. An introduced population of the Saratoga Springs pupfish (Cyprinodon nevadensis nevadensis) inhabits Lake Tuendae, but this species has at exceptionally low densities, not affording us the opportunity to evaluate its role in the fish community.

Mohave tui chub and western mosquitofish at Lake Tuendae are members of the same feeding guild (88% food niche overlap, Morisita’s index; Morisita 1959; Appendix A). Thus to limit competition, fish were fed ground pelleted fish food at a ration of 4% of stocked fish biomass per day. This feeding ration was based on our experience from laboratory rearing of both species and our previous mesocosm experiments (Stockwell and Henkanaththegedara

2011). The biomass of mosquitofish was determined based on a weight of 75 randomly picked

(25 males and 50 females) Lake Tuendae mosquitofish.

Mesocosm Sampling

The mesocosm experiment was initiated 8 March 2009, prior to the active breeding season of both fish species, and continued until 12 May 2009 when mesocosm temperatures reached 32 oC (upper thermal tolerance for Mohave tui chubs is 33.5-36.2 oC; McClanahan et al.

1986). All mesocosms were inspected daily for water level, fish mortality, and aeration. Water level in each mesocosm was maintained by adding well water every 2-3 days. Physico-chemical parameters of all mesocosms were tested biweekly. Water temperature, salinity, and dissolved oxygen were tested using a YSI 85 meter. Turbidity was measured with a Micro TPI portable turbidimeter and pH was measured using a Hanna pH-EC-TDS meter. Ammonia contents were tested once in each tank during the first 2 weeks using Jungle Quick Dip ammonia test kits and subsequently tested in 10 randomly selected tanks biweekly.

At the conclusion of the experiment, all surviving fish including larval stages, were collected and enumerated by seining each tank 5 times (Rogowski and Stockwell 2006) and then filtering all tank water through a fine mesh net. All mosquitofish were counted, euthanized with a lethal dose of MS-222 (500 mg/L) and preserved in 10% formalin. All Mohave tui chub adults and larvae were counted. A sub-sample of Mohave tui chub larvae (up to 30 from each tank) were retained as vouchers and remaining larvae and all adult tui chubs were released to Lake

Tuendae.

Fish Measurements

To evaluate size selective predation, the size of mosquitofish which survived to the end of the experiment was measured. Wet mass of formalin fixed individual mosquitofish were measured (nearest 0.1 mg; Denver Instrument Company; model A-250), as well as total length, and body depth (at the base of pelvic fins) (nearest 0.01 mm).

Data Analysis

There were no significant differences of tui chub size between the MTC and MTC+WMF treatments in terms of initial wet biomass (F1,159 = 0.00; P > 0.05), initial average total length

(F1,159 = 0.08; P > 0.05) and average gape size (F1,159 = 0.08; P > 0.05). Thus, those parameters were not utilized as covariates for subsequent analysis.

To evaluate population level treatment effects, we considered mesocosms as the unit of replication for fish population sizes. To characterize population level responses, we examined the following response variables: (1) Mohave tui chub larvae, (2) male mosquitofish, (3) female mosquitofish, (4) juvenile mosquitofish, (5) per capita production of mosquitofish juveniles

(juveniles/adult female) and (6) per capita production of tui chub larvae (larvae/adults). Because the western mosquitofish is sexually dimorphic, male and female population sizes were examined separately for this species. The treatment effects on population sizes were tested using the 2-tail, 2-sample Wilcoxon test (NPAR1WAY Procedure) with a normal approximation for both mosquitofish and Mohave tui chub responses (SAS v. 9.2; SAS Institute 2009).

Individual mosquitofish were treated as replicates when analyzing mean treatment differences of mosquitofish body size. Hence, tanks were nested within treatments to capture tank effects. Separate ANOVA mixed effects models (GLIMMIX Procedure) were ran for each morphometric trait considering treatments as a fixed factor and tanks as a random factor (SAS v.

9.2; SAS Institute 2009). Because, unbalanced designs can result in unreliable p-values for nested ANOVA (Hurlbert 1984; Quinn and Keough 2002), we also used 2-sample Wilcoxon test on the replicate means (mesocosm means) to test for treatment effects on mosquitofish total length, body depth and body mass (SAS v. 9.2; SAS Institute 2009).

(A) (B)

2 9

Figure 2.1. Components of 320 gallon tank set up used for mesocosm experiment; (A) a schematic cross section of a tank; (B) the tank set up in the field (Photo: Sujan Henkanaththegedara).

Results

Mesocosm Conditions

Most physico-chemical characteristics of mesocosms did not significantly vary among treatments but all varied across time (Table 2.1). Dissolved oxygen varied significantly among treatments but, continuous aeration of mesocosms kept the oxygen levels above the desired minimum levels for fish (5 mg/L; Davis 1975). In addition, the significant variations of pH among treatments and significant interactions with time were well within the recorded variation of pH in tui chub habitats (Henkanaththegedara and Stockwell Personnel Observations).

Mesocosm water temperature gradually increased from 17.85 oC (SE ± 0.18) in mid-March to

30.55 oC (SE ± 0.03) in early May. Salinity increased from 2.39 ppt (SE ± 0.01) to 4.24 ppt (SE

± 0.02) and turbidity of the mesocosms also increased due to growth of algae from 4.31 NTU

(SE ± 0.18) to 11.83 NTU (SE ± 0.40). Water pH slightly increased towards the end of the experiment, but remained within the acceptable range for these fish species.

Fish Survival

Mosquitofish population size was significantly lower (W = 155.0; P < 0.001) in the presence of tui chubs (22.1 ± 4.0 mosquitofish/mesocosm) compared to allopatric mosquitofish populations (157.2 ± 26.9 mosquitofish/mesocosm). Notably, mosquitofish were extirpated from one of the sympatric tanks. Male mosquitofish survival was significantly lower (W = 155.0;

P < 0.001; Figure 2.3-a) in the presence of tui chubs (0.8 ± 0.5) compared to male survival in allopatric mosquitofish populations (22.5 ± 1.3). Female mosquitofish survival was also significantly reduced in the presence of Mohave tui chubs (17.2 ± 3.6), compared to female mosquitofish survival from allopatric populations (52.5 ± 0.9; W = 155.0; P < 0.001; Figure 2.3-

30 b). In addition, the survival of sympatric mosquitofish was sex-biased, with exceptionally low male survival (3%) relative to female survival (34%).

Table 2.1. ANOVA summary table for water quality variations in mesocosms.

Source df MS F-value p-value Temperature Treatment 2 0.43 0.62 0.36 Time 4 745.24 1068.30 <0.0001 Treatment*Time 8 0.18 0.26 0.90 Error 135 0.70 Dissolved Oxygen Treatment 2 3.98 9.73 <0.001 Time 4 16.62 40.65 <0.0001 Treatment*Time 8 0.30 0.73 0.19 Error 135 0.41 Salinity Treatment 2 0.00 0.03 0.93 Time 4 14.84 1618.10 <0.0001 Treatment*Time 8 0.01 0.83 0.09 Error 135 0.01 Turbidity Treatment 2 2.20 0.49 0.38 Time 4 400.85 89.79 <0.0001 Treatment*Time 8 1.69 0.38 0.65 Error 135 4.46 pH Treatment 2 0.05 3.89 <0.05 Time 4 0.83 66.42 <0.0001 Treatment*Time 8 0.02 1.55 <0.05 Error 135 0.01

Tui chub presence had a significant effect on mosquitofish juvenile production. Notably, juveniles were not produced in 6 of the 10 sympatric tanks, but one of these 6 tanks also experienced loss of adults as well. Excluding this latter tank, mosquitofish productivity was

31 significantly lower for the sympatric tanks (4.6 ± 2.9 juveniles/mesocosm) compared to the allopatric tanks (82.2 ± 26.4 juveniles/mesocosm; W = 48.5, P < 0.001; Figure 2.3-c). After controlling for adult survival, sympatric mosquitofish populations had significantly lower per capita larval production (0.8 ± 0.5 juveniles/female/mesocosm) compared to allopatric mosquitofish populations (1.5 ± 0.5 juveniles/female/mesocosm; W = 63.0; P < 0.05; Figure 2.3- d).

Mosquitofish Size

Tui chubs apparently preyed on small adult mosquitofish in sympatry. Male mosquitofish, which are notably smaller than female mosquitofish, had high survival in allopatry

(90% survival), but extremely low survival when sympatric with Mohave tui chub (3% survival;

Figure 2.3-a). Furthermore, female mosquitofish from sympatric populations had significantly larger body mass (0.97 g ± 0.02) than female mosquitofish from allopatric mosquitofish populations (0.80 g ± 0.01; F1,17 = 10.18; P < 0.01; Figure 2.4-a), suggesting that larger females were less vulnerable to Mohave tui chub predation.

Female mosquitofish from sympatric populations were significantly longer (40.45 mm ±

0.32) compared to females from allopatric populations (36.82 mm ± 0.18; F1,17 = 26.59 ;

P < 0.0001; Figure 2.4-b). However, female mosquitofish body depth did not significantly differ between two groups (F1,17 = 2.00; P > 0.05) (Figure 2.4-c). Non-parametric analyses also showed that sympatric female mosquitofish were significantly larger than allopatric females in terms of total length (W = 133, P < 0.001) and body mass (W = 120.5, P < 0.05), but not body depth (W = 105, P > 0.05).

Figure 2.2. Mohave tui chub (Siphateles bicolor mohanvensis) total (a) and per capita (b) recruitment in the presence (sympatric; MTC + WMF) and absence (allopatric; MTC) of mosquitofish (Gambusia affinis) is shown. Error bars represent 1 ± SE.

3 4

Figure 2.3. Average mosquitofish (Siphateles bicolor mohanvensis) survival for adult male (a), adult female (b), juveniles (c), and per capita mosquitofish (Gambusia affinis) recruitment (d) in the presence (sympatric; MTC + WMF) and absence (allopatric; WMF) of Mohave tui chubs. Error bars represent 1 ± SE.

Figure 2.4. The size of surviving female mosquitofish (Gambusia affinis) in the presence (sympatric; MTC + WMF) and absence (allopatric; WMF) of Mohave tui chubs (Siphateles bicolor mohanvensis) in terms of (a) body mass, and (b) total length), and (c) body depth. Error bars represent 1 ± SE.

Discussion

This study provides experimental evidence for IGP between non-native western mosquitofish and the protected Mohave tui chub. As expected, mosquitofish had significant impacts on Mohave tui chub recruitment by reducing the larval survival in sympatric mesocosms. Reduced recruitment was probably due to mosquitofish predation on tui chub eggs and/or larvae, rather than competition, because food was provided. Further, it is noteworthy that mosquitofish preyed on tui chub larvae during laboratory trials (Henkanaththegedara and

Stockwell Unpublished Data). Other workers have reported mosquitofish predation as the primary mechanism of mosquitofish impact on native fishes (Belk and Lydeard 1994; Rincon et al. 2002; Mills et al. 2004). Therefore, we suspect mosquitofish predation on tui chub eggs and/or larvae as the primary cause for the reduction of tui chub recruitment in sympatric tanks.

Surprisingly, tui chub presence also significantly impacted mosquitofish populations. As expected, allopatric mosquitofish populations increased rapidly with a two-fold increase in total population size in less than 10 weeks. By contrast, tui chubs caused mosquitofish populations to decrease by approximately 70%, with complete extirpation in one mesocosm. These population effects were due to reduced adult survival and reduced larval production. In fact, sympatric mosquitofish did not produce offspring in 60% of the tanks, and overall mosquitofish juvenile production was substantially reduced in the presence of tui chubs. Decreased mosquitofish juvenile production may be partly due to fewer females contributing juveniles; however, after controlling for adult female survival, the per capita mosquitofish recruitment was still reduced by

50% for sympatric populations.

Collectively, our results provide evidence for IGP between endangered Mohave tui chub and non-native western mosquitofish. This case of IGP appears to be size structured with adult

Mohave tui chub preying on adult (and juvenile) mosquitofish, and adult mosquitofish preying on tui chub eggs and/or larvae. Mohave tui chub predation on adult mosquitofish is apparently gape-limited, as has been reported for other systems with piscivorous fish species (Hambright et al. 1991; Nilsson and Bronmark 2000). Larger mosquitofish females apparently avoided predation by Mohave tui chub, which is consistent with gape-size limited tui chub predation.

Low male survival is also consistent with the gape size limitation hypothesis as male mosquitofish are much smaller than females. Overall, size-structured IGP may facilitate co- existence of native and non-native species. In fact, IGP has been shown to be very important in determining structure and stability for a variety of communities (Arim and Marquet 2004). We suggest that IGP plays a role in co-persistence of Mohave tui chub and western mosquitofish. In fact, mosquitofish and tui chubs have co-existed for at least 27 years in China Lake (U.S. Fish and Wildlife Service 1984) and 9 years in Lake Tuendae (Steve Parmenter Personnel

Communication).

In addition to IGP, other mechanisms such as niche partitioning may play an important role in promoting co-persistence of Mohave tui chub with mosquitofish in the wild. For instance, spatial and temporal habitat partitioning may limit impacts of western mosquitofish on native fishes (Barrier and Hicks 1994; Ling 2000; Ayala et al. 2007). Spatial and temporal niche partitioning between adult mosquitofish and tui chubs in Lake Tuendae has yet to be quantified.

Exploring the mechanisms that may permit co-persistence was not an original objective for this project. In fact, our initial work (Stockwell and Henkanaththegedara 2011) was influenced by the prevailing dogma that mosquitofish constitute an important threat to many native aquatic species (Courtenay and Meffe 1989; Pyke 2008). In a more general sense, this dogmatic view has influenced conservation planning with mosquitofish identified as a threat for

37 the recovery of a variety of listed fish and amphibian species. We searched the Endangered

Species Recovery Plans Database (U.S. Fish and Wildlife Service 2011) and found that western mosquitofish (G. affinis) was identified as a limiting factor for 18% of amphibian (n=17) and

25% of fish (n=110) species and populations. For example, western mosquitofish (G. affinis) have been identified as a limiting factor in recovery plans for 6 of 7 Cyprinodontids (pupfish), 3 of 4 Goodeids (poolfish and springfish), all 6 species of Poeciliids (mosquitofish and topminnows) and both Ranid frogs (U.S. Fish and Wildlife Service 2011). However, evidence demonstrating that mosquitofish limit recovery has been largely anecdotal with very limited experimental work. Therefore we argue that additional work is warranted to verify if mosquitofish presence truly constrains recovery of such protected species.

The dogmatic views of mosquitofish as a universally “bad” further constrain available management options. The Mohave tui chub recovery plan calls for establishing 6 geographically isolated, self-sustaining populations for down-listing the status of this species from Endangered to Threatened (U.S. Fish and Wildlife Service 1984). When this work started, there were 4 populations that counted as 3 geographically isolated populations toward the down- listing goal of 6 established populations, thus seeking suitable refuge sites has been a high priority for tui chub recovery. It is noteworthy that this research suggests mosquitofish presence may not necessarily limit the suitability of a site for colonization by Mohave tui chub. Indeed, a forth population of Mohave tui chub was recently established at a site inhabited by mosquitofish

(i.e. Deppe Pond/tui slough system; M. Huffine, Personnel Communication).

These findings support an emerging view calling for a more nuanced and sophisticated evaluation of non-native species (Davis et al. 2011; Prévot-Julliard et al. 2011; Schlaepfer et al.

2011). Understanding the complex interactions among native and non-native species in the

38 whole-ecosystem context may help conservation practitioners identify novel management options.

Literature Cited

Arim, M., and P. A. Marquet. 2004. Intraguild predation: a widespread interaction related to

species biology. Ecology Letters 7:557-564.

Arthington, A.H. 1984. Freshwater fishes of Stradbroke, Moreton and Fraser Islands, Pages 279-

282. In Covacevich, J. and J. Davie, editors. Focus on Stradbroke. Boolarong Press,

Brisbane. Australia.

Ayala, J. R., R. B. Rader, M. C. Belk, and G. B. Schaalje. 2007. Ground-truthing the impact of

invasive species: spatio-temporal overlap between native least chub and introduced

western mosquitofish. Biological Invasions 9:857-869.

Bampfylde, C. J. and M. A. Lewis. 2007. Biological control through intraguild predation: case

studies in pest control, invasive species and range expansion. Bulletin of Mathematical

Biology 69:1031-1066.

Barrier, R. F. G., and B. J. Hicks. 1994. Behavioral interactions between back mudfish

(Neochanna diversus Stokell, 1949: Galaxiidae) and mosquitofish (Gambusia affinis

Baird and Girard, 1845). Ecology of Freshwater Fish 3:93-99.

Belk, M. C., and C. Lydeard.1994. Effects of Gambusia holbrooki on a similar-sized, syntopic

poeciliid, Heterandria formosa: competitor or predator? Copeia 1994:296-302.

Brooking, T. E., L. G. Rudstam, M. H. Olson, and A. J. VanDeValik. 1998. Size-dependent

alewife predation on larval walleyes in laboratory experiments. North American Journal

of Fisheries Management 18:960-965.

Bull, L. S. and F. Courchamp. 2009. Management of interacting invasives: ecosystem

approaches. Pages 232-247. In M. N. Clout, and P. A. Williams, editors. Invasive species

management: A handbook of principles and techniques. Oxford University Press, New

York.

Courchamp, F. and S. Caut. 2006. Use of biological invasions and their control to study the

dynamics of interacting populations. Pages 253-279. In M. W. Cadotte, S. M. McMahon,

and T. Fukami, editors. Conceptual ecology and invasions biology. Kluwer Academic,

New York.

Courtenay, W. R. Jr. and G. K. Meffe. 1989. Small fishes in strange places: A Review of

introduced Poecillids. Pages 319-333. In G. K. Meffe and F. F. Snelson, Jr., editors.

Ecology and Evolution of live-bearing fishes (Poecillidae). Prentice Hall, New Jersey.

Davis, M.A., et al. 2011. Don't judge species on their origins. Nature 474:153–154

Davis, J. C. 1975. Minimal dissolved oxygen requirements of aquatic life with emphasis on

Canadian species: a review. Journal of the Fisheries Research Board of Canada 32:2295-

2332.

Deacon, J.E., C. Hubbs and B.J. Zahuranec. 1964. Some effects of introduced fishes on the

native fish fauna of southern Nevada. Copeia 1964: 384-388.

Fitzgerald, B. M. 1988. Diet of domestic cats and their impact on prey populations. Pages 123-

146. In D. C. Turner, editor. The Domestic Cat: The biology of its behavior. Cambridge

University Press. Cambridge, U.K.

Galat, D.L. and B. Robertson. 1992. Response of endangered Poeciliopsis occidentalis

sonoriensis in the Rio Yaqui drainage, Arizona, to introduced Gambusia affinis.

Environmental Biology of Fishes 33: 249-264.

Hambright, K. D., R. W. Drenner, S. R. McComas, and N. G. Hairstone. 1991. Gape-limited

piscivores, planktivore size refuges, and the trophic cascade hypothesis. Archiv fur

Hydrobiologie 121:389-404.

Hurlbert, S. H. 1984. Pseudoreplication and the design of ecological experiments. Ecological

Monographs 54:187-211.

Hurlbert, S. H., J. Zedler and D. Fairbanks. 1972. Ecosystem alteration by mosquitofish

(Gambusia affinis) predation. Science 175:639-641.

Karl, B. J., and H. A. Best. 1982. Feral cats on Stewart Island; their foods and their effects on

kakapo. New Zealand Journal of Zoology 9:287-294.

Lerdaue, M. and J.D. Wickham. 2011. Non-natives: four risk factors. Nature 475:36-37.

Lindenmayer, D. and M. Hunter. 2010. Some guiding concepts for conservation biology.

Conservation Biology 24:1459-1468.

Ling, N. 2004. Gambusia in New Zealand: really bad or just misunderstood? New Zealand

Journal of Marine and Freshwater Research 38:473-480.

Lookwood, J.L., M.F. Hoopes, and M.P. Marchetti. 2011. Non-natives: plusses of invasion

ecology. Nature 475: 36.

Lowe, S., M. Browne, S. Boudjelas, M. De Poorter. 2000. 100 of the World’s Worst Invasive

Alien Species A selection from the Global Invasive Species Database. The Invasive

Species Specialist Group (ISSG), the World Conservation Union (IUCN). Auckland,

New Zealand.

McClanahan, L. L., C. R. Feldmeth, J. Jones, and D. L. Soltz. 1986. Energetics, salinity and

temperature tolerance in the Mohave tui chub, Gila bicolor mohavensis. Copeia 1986:45-

52.

McCullough, C. 1998: The voracious mosquitofish: Gambusia or Damnbusia? Forest and Bird

November 1998:20–21.

Meffe, G. K. 1985. Factors resulting in decline of the endangered Sonoran topminnow

Poeciliopsis occidentalis (Atheriniformes: Poeciliidae) in the United States. Biological

Conservation 25:135-159.

Mills, M. D., R. B. Rader and M.C. Belk. 2004. Complex interactions between native and

invasive fish: the simultaneous effects of multiple negative interactions. Oecologia

141:713-721.

Minckley, W. L. and J.E. Deacon. 1968. Southwestern fishes and the enigma of “endangered

species”. Science 159:1424-1432.

Morisita, M. 1959. Measuring of interspecific association and similarity between communities.

Memoirs of the Faculty of Science Kyushu University Series E3: 65-80.

Myers, G. S. 1965: Gambusia, the fish destroyer. Australian Zoologist 13:102.

Nilsson, P. A. and C. Bronmark. 2000. Prey vulnerability to a gape-size limited predator:

behavioural and morphological impacts on northern pike piscivory. Oikos 88:539-546.

Prévot-Julliard, A. J. Clavel, P. Teillac-Deschamps and R. Julliard. 2011. The need for flexibility

in conservation practice: exotic species as an example. Environmental Management

47:315-321.

Polis, G. A. and R. D. Holt. 1992. Intraguild predation: The dynamics of complex trophic

interactions. Trends in Ecology and Evolution 7:151-154.

Polis, G. A., C. A. Myers, and R. D. Holt. 1989. The ecology and evolution of intraguild

predation: potential competitors that eat each other. Annual reviews of Ecology and

Systematics 20:297-330.

Pyke, G. H. 2008. Plague minnow or mosquitofish? A review of the biology and impacts of

introduced Gambusia species. Annual review of Ecology, Evolution and Systematics.

39:171-191.

Quinn, G. P. and M. J. Keough. 2002. Experimental design and data analysis for biologists.

Cambridge University Press, Cambridge, U.K.

Rincon, P. A., A. M. Correas, F. Morcillo, P. Risueno and J. Lobon-Cervia. 2002. Interaction

between the introduced eastern mosquitofish and two autochthonous Spanish toothcarps.

Journal of fish biology 6:1560-1585.

Roemer, G. W., C. J. Donlan, F. Courchamp. 2002. Golden eagles, feral pigs, and insular

carnivores: how exotic species turn native predators in to prey. Proceedings of the

National Academy of Science 99:791-796.

Rogowski, D. L. and C. A. Stockwell. 2006. Assessment of potential impacts of exotic species

on populations of a threatened species, White Sands pupfish, Cyprinodon tularosa.

Biological Invasion 8:79-87.

SAS Institute. 2009. SAS/STAT (r) 9.2 User's Guide (2nd Edition). Cary, North Carolina.

Sax, D. F., S. D. Gaines, and J. J. Stachowicz. 2005. Species invasions: Insights in to Ecology,

Evolution and Biogeography. Sinauer Associates, Inc., Sunderland, Massachusetts.

Schlaepfer, M.A., D. F. Sax, and J. D. Olden. 2011. The potential conservation value of non-

native species. Conservation Biology 25:428-437.

Schneider, J. C., and J. H. Leach. 1977. Walleye fluctuations in the Great Lakes and possible

causes, 1800-1975. Journal of the Fisheries Research Board of Canada 34:1878-1889.

Simberloff, D. 2011. Non-natives: 141 scientists object. Nature 475:36.

Soule, M. 1991. Conservation: tactics for a constant crisis. Science 253:744-750.

Stockwell, C. A. and S. M. Henkanaththegedara. 2011. Evolutionary conservation biology of

Poeciliids. Pages 128-141. In J. Evan, A. Pilastro and I. Schlupp, editors. Ecology and

Evolution of Poeciliid Fishes. University of Chicago Press. Chicago, Illinois.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. United States Fish and Wildlife Service, Portland, Oregon.

U.S. Fish and Wildlife Service. 2011. Endangered species program: recovery plans search.

Available from http://www.fws.gov/endangered/species/recovery-plans.html (accessed

December 2011)

Zavaleta, E. S., R. J. Hobbs, and H. A. Mooney. 2001. Viewing invasive species removal in a

whole-ecosystem context. Trends in Ecology and Evolution 16:454-459.

CHAPTER 3. THE ROLE OF GAPE-LIMITATION IN INTRAGUILD

PREDATION BETWEEN NATIVE AND NON-NATIVE FISH*

Submitted to Canadian Journal of Fisheries and Aquatic Sciences as: Sujan

Henkanaththegedara1 and Craig Stockwell1. The role of gape-limitation in intraguild predation between native and non-native fish

1 Environmental and Conservation Sciences Graduate Program, Department of Biological

Sciences, North Dakota State University Dept. 2715, P.O. Box 6050, Fargo ND 58108-6050.

Abstract

Intraguild predation (IGP) is a mechanism that may facilitate the co-persistence of native species with non-native invasive species. We conducted laboratory predation trials to assess the role of predator gape-limitation in the context of IGP between the endangered Mohave tui chubs

(Siphateles bicolor mohavensis) and invasive western mosquitofish (Gambusia affinis). We explored sex specific differences in gape-size limitation in mosquitofish, because female mosquitofish have notably larger body depths and gape-sizes than male mosquitofish. Larval tui chubs had significantly lower (χ2 = 74.74; P < 0.001) survival in the presence of female mosquitofish (10.0%) than in the presence of male mosquitofish (73.3%). Reciprocally, adult tui chubs preyed upon adult mosquitofish causing a significantly lower (χ2 = 11.33; P < 0.001) survival for male mosquitofish (60%) compared to female mosquitofish survival (96.7%). The average depth/gape ratios for consumed fish were 0.91 (± 0.03; N = 12) and 0.72 (± 0.04; N =

27), for tui chub and mosquitofish predators, respectively. Vulnerability modeling revealed that mosquitofish with a body depth less than 4.4 mm and a larval tui chub with a body depth less than 1.8 mm were completely vulnerable to predation by Mohave tui chub and mosquitofish, respectively. My results suggest that IGP in this study system is size structured based on gape- size limitation and may have some conservation implications for the recovery of endangered

Mohave tui chub.

Introduction

Predation has widespread ecological effects both on community structure (Sih et al. 1985;

Diehl 1992; Post et al. 2008) and life history evolution of interacting organisms (Reznick et al.

1990; Stibor 1992; Ingram et al. In Press). However, the relative roles of predator and prey are not static, and individuals of a single species may act as both predator and/or prey, depending on their age and size (Polis et al. 1989; Polis and Holt 1992). Such intraguild predation (IGP) is a widespread phenomenon in nature (Polis and Holt 1992; Arim and Marquet 2004); yet, few studies have evaluated how IGP may affect the co-persistence of native and non-native species

(Taniguchi et al. 2002; Arim and Marquet 2004).

In theory, IGP may facilitate invasion dynamics, but IGP may also facilitate the co- persistence of native species with non-natives. Taniguchi et al. (2002) showed how IGP provided a competitive advantage for non-native, stream-dwelling rainbow trout (Oncorhynchus mykiss) over native, anadromous Masu salmon (O. masou), facilitating rainbow trout invasion in

Japanese streams. By contrast, size structured IGP may facilitate co-persistence of endangered

Mohave tui chub (Siphateles bicolor mohavensis) with non-native western mosquitofish

(Gambusia affinis; Stockwell and Henkanaththegedara 2011; Henkanaththegedara and Stockwell

47 unpublished data). In both case studies, IGP appeared to be size-structured based on predator gape-size limitation.

The vulnerability of prey to potential predation is often limited by the gape-size of predators relative to the size of their prey (Hambright 1991; Nilsson and Bronmark 2000;

Magnhagen and Heibo 2001; Webb and Shine 1993). For example, Magnhagen and Heibo

(2001) reported a positive correlation between gape-size of northern pike (Exos lucius) and body depth of its piscine prey. When gape-size is a limiting factor, predation risk is reduced as the prey grows and body depth approaches and ultimately exceeds the predator’s maximum gape- size (Hambright et al. 1991; Nilsson et al. 1995). Therefore, predator gape-size and prey body depth may have important implications in a system where predation is structured based on relative body sizes of predator and prey.

We report a case of IGP between endangered Mohave tui chub and non-native western mosquitofish, where tui chubs preyed on adult and juvenile mosquitofish while mosquitofish preyed on eggs and larvae of tui chubs (Henkanaththegedara and Stockwell unpublished data).

Two lines of evidence suggest that IGP between these two species is structured by gape-size limitation. First, male mosquitofish, which is the smaller sex of this dimorphic species, had very low survival (3%) compared to female mosquitofish (34%) in the presence of Mohave tui chub.

Second, female mosquitofish that survived in the presence of adult tui chubs were relatively large. Reciprocally, mosquitofish preyed upon Mohave tui chub larvae, which is also likely to be gape-limited (Henkanaththegedara and Stockwell Unpublished Data; also see Mills et al. 2004).

Here, we report the results of a series of laboratory predation trials designed explicitly to assess gape-limitation in the context of IGP between Mohave tui chub and western mosquitofish.

We also present a prey vulnerability model (Hambright et al. 1991) which allows us evaluate how gape-size limited predation affects each fish population.

Methods

Laboratory Predation Experiments

Predation on adult western mosquitofish was assessed by using adult Mohave tui chubs

(sexually monomorphic) as candidate predators. We tested both adult male and female mosquitofish as candidate prey because mosquitofish are sexually dimorphic. Mohave tui chubs were collected from Lake Tuendae, MC Spring, and Camp Cady (all in southern California) in

November 2009 and transported to North Dakota State University (NDSU). Western mosquitofish were collected from Deppe Pond/Tui slough system at the Lewis Center for

Academic Excellence in Apple Valley, CA and transported to NDSU.

Sixty 37.8 L glass aquaria were used as experimental chambers. Three vertical sides of each aquarium were covered with black plastic sheets to avoid any visual interference among tanks. Aquaria were continuously aerated by a centrally suspended aerator in each tank. A full spectrum light source was placed 35 cm above each tank and a light cycle of 16 hrs light / 8 hrs dark was used.

This experimental design provided 30 replicates, using either male mosquitofish or female mosquitofish allowing an assessment of tui chub predation on mosquitofish by sex.

Mohave tui chub predators were measured for total length (nearest 1 mm) and gape-size (nearest

0.01 mm). Tui chub gape-size was measured from the ventral side (tui chubs have a sub-terminal mouth) as the linear distance between posterior limit of maxilla with mouth fully closed.

Mosquitofish were measured for total length and body depth (nearest 0.01 mm). Female

49 mosquitofish body depths were measured at the base of pelvic fins while male mosquitofish body depths were measured at the deepest point of the gonopodial base (Figure 3.1). Measured mosquitofish were kept in individual containers prior to introduction into aquaria. Mohave tui chubs assigned between the two treatments did not significantly differ in total length (t = - 1.05;

P > 0.05) and gape-size (t = -1.06; P > 0.05). As expected, female mosquitofish were significantly larger in total length (t = -12.74; P < 0.001) and gape-size (t = -11.40; P < 0.001) compared to male mosquitofish (Table 3.1).

For each predation trial, an adult tui chub was deprived of food for 24h prior to being placed in a randomly selected aquarium. After a 4hr acclimation period, a single mosquitofish was introduced into each aquarium. Survival was monitored every 3h over the 72h test period and time to death (TTD) was recorded for each mosquitofish.

Mosquitofish predation on larval tui chubs was assessed by using either adult male or adult female mosquitofish as candidate predators and Mohave tui chub larvae as candidate prey

(Table 3.1). For these trials, mosquitofish were obtained from a commercial stock from Arizona

(Arizona Aquatic Gardens; www.azgardens.com). Mohave tui chub larvae were provided by

Mojave National Preserve, California (Debra Hughson Personnel Communication).

Small 4.7 L opaque plastic containers were used as experimental chambers. Chambers were not aerated due to the short experimental time period and low fish density. This experiment consisted of two predator treatments, male and female mosquitofish, with 30 replicates each. In addition, we included a control of Mohave tui chub larvae maintained in the absence of mosquitofish (n = 28), to account for any mortality of tui chub larvae due to handling stress.

Figure 3.1. Body depth measurements of a Mohave tui chub larvae (Siphateles bicolor mohavensis) (A), a mature male (B) and a pregnant female (C) of western mosquitofish (Gambusia affinis; Illustrated by Sujan Henkanaththegedara).

Table 3.1. Size of Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) utilized for predation experiments.

Experiment / Measurement Prey Treatment N t-value p-value ♂ mosquitofish ♀ mosquitofish Mohave tui chubs as predators Adult Mohave tui chub Total length (mm) 101.70 (± 2.68) 105.50 (± 2.43) 30 -1.049 > 0.05 Gape-size (mm) 6.24 (± 0.20) 6.54 (± 0.20) 30 -1.057 > 0.05

Total length (mm) 30.00 (± 0.29) 40.72 (± 0.79) 30 -12.742 < 0.001

Body depth (mm) 6.22 (± 0.06) 8.31 (± 0.17) 30 -11.404 < 0.001

2 2 2 2 2 52

7 7 7 7 7

Mosquitofish as predators Adult western mosquitofish Total length (mm) 26.02 (± 0.66) 38.12 (± 0.88) 30 -11.013 < 0.001 Gape-size (mm) 2.00 (± 0.04) 3.43 (± 0.09) 30 -14.590 < 0.001

Larval Mohave tui chub Total length (mm) 13.78 (± 0.48) 14.67 (± 0.54) 30 -1.243 > 0.05 Estimated body depth (mm) 2.30 (± 0.09) 2.47 (± 0.10) 30 -1.243 > 0.05

Mosquitofish predators were measured for total length and gape-size (nearest 0.01 mm).

Mosquitofish gape-size was measured dorsally due to superior nature of their mouths. Again, male mosquitofish were significantly smaller in total length (t = -11.01; P < 0.001) and gape-size

(t = -14.59; P < 0.001) compared to female mosquitofish (Table 3.1).

Tui chub larvae were measured for total length (nearest 0.01mm) using digital calipers, while resting on a watch glass filled with a small amount of water. Subsequently, tui chub larvae were monitored for at least 3h following measurements to assess any handling associated mortality. Body depths were difficult to measure on live tui chub larvae. Therefore, we measured a sample of Mohave tui chub larvae voucher specimens to derive a regression formula of body depth on total length (body depth = 0.1986 x (total length) – 0.4251; r2 = 0.96; N = 148). Mohave tui chub larval body depth was measured at the middle of the head (Figure 3.1). The average total length of Mohave tui chub larvae exposed to mosquitofish predation did not significantly differ between male and female mosquitofish treatments (t = -1.24; P > 0.05; Table 3.1).

Adult mosquitofish were deprived of food for 24h prior to being placed in a randomly selected experimental chamber. After the 4h acclimatization period, a single tui chub larva was introduced into each experimental chamber and its survival was monitored every 15 minutes over a 4h test period and TTD was recorded for each tui chub larva.

Statistical Analysis

We conducted all statistical analyses using R statistical software program Version 2.11.0

(R Development Core Team 2010). Package survival was utilized to analyze prey survival

(Therneau and Lumley 2009). This package uses the Surv( ) function to simultaneously evaluate

TTD and the censoring information (0=live; 1=dead; Maindonald and Braun 2010). Survival functions were estimated with Kaplan-Meier survival estimate (survfit function) using TTD data.

Hazard functions for treatment groups were tested using Cox proportional hazards model (coxph function).

The ratio between prey body depth and predator gape width (here after depth/gape ratio) was utilized to assess gape-size limitation. In theory, predators could not consume prey larger than their gape-size (Hambright et al. 1991); hence the depth/gape ratio should be ≤ 1.0 for prey consumed and > 1.0 for survivors. We ran separate one-sample, 2-tail t-tests (t.test function) with depth/gape ratios using a null hypothesis of µ = 1 to detect any significant deviations from 1

(when prey body depth = predator gape-size) after testing data for normality with a Shapiro-Wilk normality test (shapiro.test function). Prey which were presumably killed by the predator but not consumed were excluded from these analyses (mosquitofish as predator, N = 5; tui chubs as predator, N = 1).

Vulnerability Modeling

Hambright et al.’s (1991) vulnerability model assumes that predator gape-size and prey body depth are the critical factors which determine the prey size ingested by a predator. Relative vulnerability of prey (V) to predation was estimated as a function of prey body depth (d) and the frequency of predators’ gape-size (W) in the predator population.

∑

Prey with body depths larger than the gape-size of the largest individual of predator population were considered to be unavailable for predation (i.e., V = 0). However, prey with body depths smaller or equal to the gape-size of the smallest individual of the predator population were considered to be completely vulnerable to all the predators in the community

(i.e., V = 1). The prey with intermediate body depths are vulnerable to a proportion of the predator population depending on the body depth (0 < V < 1).

Relative vulnerabilities of adult mosquitofish and larval tui chubs were estimated using the cumulative gape-size frequency distributions for the Lake Tuendae populations of adult

Mohave tui chub and adult mosquitofish respectively (Table 3.2). Corresponding total lengths of mosquitofish were estimated using two regression formulas relating body depth to total length based on fish collected from Lake Tuendae in March-May 2009 (females: total length = (body depth + 3.0746) / 0.3017; r2 = 0.85; N = 90, males: total length = (body depth + 0.2775) / 0.2123; r2 = 0.76; N = 79). Adult chubs were collected in 2008 from Lake Tuendae, Camp Cady, China

Lake (N = 30 each) and MC Spring (N = 24). Mosquitofish were collected from Lake Tuendae in

2009 (N = 149). The gape-size of tui chubs and mosquitofish were measured as previously described.

Table 3.2. Size of Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) utilized for vulnerability modeling.

Species/measurement (mm) N Average (±SE) Range Mohave tui chub Adults TL 114 107.19 (± 2.11) 62.71 - 150.85 Gape 114 7.92 (± 0.17) 4.34 - 12.62

Larvae TL 178 15.77 (± 0.52) 6.19 - 44.67 Depth 178 2.70 (± 0.10) 3.59 - 10.30

Western mosquitofish Females TL 90 32.30 (± 0.56) 21.63 - 45.38 Gape 90 2.76 (± 0.05) 1.74 - 4.16 Depth 90 6.67 (± 0.18) 3.59 - 10.30

Males TL 59 25.30 (± 0.25) 20.54 - 29.20 Gape 59 1.83 (± 0.03) 1.19 - 2.46 Depth 59 5.06 (± 0.07) 3.77 - 6.01

Results

Laboratory Predation Experiments

Survival in the presence of tui chubs was significantly lower (χ2 = 11.33; d.f. = 1; p <

0.001) for male mosquitofish (60.0%; 95% CI: 44.8 - 80.4%) than for female mosquitofish

(96.7%; 95% CI: 90.4 - 100.0%; Figure 3.2-A) The average depth/gape ratio for male mosquitofish consumed by tui chub predators (0.91 ± 0.03; N = 12) was significantly lower than

1.0 (t = -3.13; d.f. = 11; p < 0.01), whereas the depth/gape ratio for male mosquitofish survivors

(1.11 ± 0.05; N = 18) was significantly greater than 1.0 (t = 2.22; d.f. = 17; p = 0.0406).

Furthermore, 29 out of 30 female mosquitofish survived the experiment (1 killed but not consumed) and their average depth/gape ratio (1.31 ± 0.06) was significantly higher than 1.0 (t =

5.14; d.f. = 28; p < ).0001). Because of small sample size, we did not test the depth/gape ratio for the single non-surviving female mosquitofish.

Tui chub larval survival in the absence of mosquitofish was 100%, suggesting that handling stress was limited. Mohave tui chub larval survival was significantly lower (χ2 = 74.74; d.f. = 1; p < 0.001; Figure 3.2-B) in the presence of female mosquitofish (10.0%; 95% CI: 3.4 -

29.3%), than in the presence of male mosquitofish (73.3%; 95% CI: 59.1 - 91.0%). The average depth/gape ratio for tui chub larval prey consumed by female mosquitofish (0.72 ± 0.04; N = 27) was significantly less than 1.0 (t = -6.5; d.f. = 26; p < 0.0001). The depth/gape ratio was not tested for the small sample of tui chub larvae that survived in the presence of female mosquitofish. The average depth/gape ration for the tui chub larvae survived with male mosquitofish predators (1.22 ± 0.06; N = 22) was significantly higher than 1.0 (t = 3.58; d.f. =

21; p < 0.01). The depth/gape ratio was not tested for the small sample of tui chub larvae that were consumed by male mosquitofish.

Vulnerability Modeling

Vulnerability modeling revealed that mosquitofish with a body depth less than 4.4 mm

(total length, female: 24.8 mm, male: 22.0 mm) were completely vulnerable to tui chub predation. However, with increasing size, vulnerability of mosquitofish to tui chub predation decreased to zero with a body depth greater than 12.8 mm (total length, female: 52.6). The body depth of male mosquitofish never reaches 12.8 mm, indicating that the entire Lake Tuendae male mosquitofish population is vulnerable to tui chub predation. Furthermore, the size distribution for the Lake Tuendae mosquitofish population shows that male mosquitofish have a higher vulnerability to tui chub predation compared to female mosquitofish. The size frequency distribution of mosquitofish from Lake Tuendae suggests that all mosquitofish have some vulnerability to tui chub predation. However, female mosquitofish population has comparatively lower vulnerability to tui chub predation compared to male mosquitofish, due to relatively large body size (Figure 3.3-A).

Tui chub larvae with body depths less than 1.8 mm (total length: 11.2 mm) were fully vulnerable to predation by all size classes of adult female mosquitofish. With tui chub larval growth, their vulnerability to female mosquitofish predation decreases. The vulnerability to predation reaches zero when tui chub larvae reach a body depth greater than 4.2 mm (total length: 23.3 mm) providing a complete size-refuge from female mosquitofish predation. Tui chub larvae with body depths less than 1.2 mm (total length = 8.2 mm) were fully vulnerable to male mosquitofish predation; however vulnerability of tui chub larvae to predation by adult male mosquitofish reached zero at a body depth of 2.6 mm (total length = 15.2 mm; Figure 3.3-B).

Figure 3.2. Kaplan-Meier estimates of proportional survival of prey during predation trials for (A) adult western mosquitofish (Gambusia affinis) prey with adult Mohave tui chub (Siphateles bicolor mohavensis) as predators and (B) Mohave tui chub larval prey with adult western mosquitofish as predator. Solid lines indicate Kaplan-Meier proportional survival function and dashed lines indicate 95% confidence intervals. Black and grey lines indicate the treatments with male and female mosquitofish respectively.

Figure 3.3. Relative vulnerability (lines) of (A) mosquitofish (Gambusia affinis) prey under adult Mohave tui chub (Siphateles bicolor mohavensis) predation and (B) Mohave tui chub larval prey under adult mosquitofish predation. Frequency distribution of body depths of mosquitofish (A) are indicated with vertical bars and were constructed based on both male (n = 79) and female (n = 90) mosquitofish collected from Lake Tuendae in March-May 2009. The dark gray bars represent the portion of female mosquitofish size distribution overlapped with male mosquitofish size distribution.

Discussion

This study provided experimental evidence that IGP between invasive western mosquitofish and native Mohave tui chub is gape-size limited. Correlated with their smaller size, male mosquitofish had higher vulnerability to tui chub predation than female mosquitofish.

Similar results were obtained from two mesocosm experiments, where tui chubs caused low survival rates for male mosquitofish compared to female mosquitofish (Stockwell and

Henkanaththegedara 2011; Henkanaththegedara and Stockwell Unpublished Data). Furthermore, gape-size limitation is indicated by the larger depth/gape ratio of surviving male mosquitofish compared to non-survivors.

The differential predation by male and female mosquitofish on tui chub larvae was also consistent with the gape-size limitation hypothesis. Adult female mosquitofish reduced tui chub larval survival to 10% whereas male mosquitofish only reduced tui chub larval survival to 73%.

Two lines of evidence suggest that mosquitofish predation on tui chub larvae was gape-limited.

First, tui chub larval survival was notably lower in the presence of female mosquitofish (larger gapes) than in the presence of male mosquitofish (smaller gapes). Second, the depth/gape ratio was significantly smaller than 1.0 for tui chub larvae consumed by female mosquitofish, whereas the few survivors all had relatively larger body depths. The gape-size limitation of mosquitofish predation on larvae of native minnows was also reported where mosquitofish co-occur with native least chub (Iotichthys phlegethontis). The survival of large young-of-the year (YOY) least chub was greater than that of smaller YOY least chub (Mills et al. 2004).

Vulnerability modeling showed that gape-size limitation is likely to have important differential effects on survival of male mosquitofish at Lake Tuendae. Male mosquitofish are more vulnerable to predation due to their relatively smaller body sizes compared to females.

Because male mosquitofish growth after sexual maturation is exceptionally slow (Hughes 1986), they are vulnerable to predation throughout their entire lifespan. By contrast, female mosquitofish have indeterminate growth (Hughes 1986), and thus can escape predation risk as they grow. These differential effects may have important implications for life history evolution of mosquitofish. For example, relatively higher predation pressure on adult male mosquitofish may lead to maturation at smaller sizes (Reznick et al. 1990).

All newly hatched tui chub larvae (total length = 6.56 ± 0.04 mm; N = 30) are completely vulnerable to both adult male and female mosquitofish predation. Tui chub larvae may reach a complete size refuge from male and female mosquitofish when they reach a total length of 14.2 mm and 21.3 mm, respectively. However, the vulnerability model proposed by Hambright et al.

(1991) is exceptionally liberal, because it assumes complete vulnerability to predation, if prey body depth is less that predator gape-size, i.e. depth/gape ratios ≤1.0. Additionally, depth/gape ratio for consumed prey ranged from 0.7 (mosquitofish predators) to 0.9 (tui chub predators) in our experiments, which would reduce proportion of population vulnerable to predation (also see

Truemper and Lauer 2005).

These findings provide an important caveat to the dogmatic view of mosquitofish as a threat whenever they invade. Mosquitofish predation on eggs and/or larvae of native fish has been widely reported as a major threat to the existence of native fish (Meffe 1985; Mills et al.

2004; Rogowski and Stockwell 2006; Pyke 2008). However, it is important to note that many previous studies involved native species with relatively small body sizes, compared to the size of mosquitofish. To further evaluate if mosquitofish impacts are limited to fishes with relatively smaller body sizes, we conducted a literature review. We searched Google scholar using the following keywords; mosquitofish, Gambusia, impacts, native fish.

In 13 of 17 case studies, mosquitofish had negative impacts on small bodied native fish species (generally less than 65 mm; Table 3.3). By contrast, the remaining four studies included larger bodied fish species and showed co-existence of both species presumably due to reciprocal predation (Blaustein 1991; this study) or habitat partitioning (Barrier and Hicks 1994) despite mosquitofish predation on larval/egg of the native species. For example, mosquitofish co-existed with black mudfish Neochanna diversus (grows up to 110 mm), despite mosquitofish predation on their larvae (Barrier and Hicks 1994; Ling 2004).

Size structured IGP has been suggested as an important mechanism allowing co-existence of various interacting predatory communities (Polis et al 1989; Holt and Polis 1997). In this case,

IGP interactions may explain the continued, long-term persistence of native Mohave tui chub with invasive mosquitofish (Henkanaththegedara and Stockwell unpublished data). In fact,

Mohave tui chub has co-persisted with western mosquitofish up to 9 years at Lake Tuendae

(Steve Parmenter Personal Communication) and up to 27 years at China Lake (U.S. Fish and

Wildlife Service 1984). Our results suggest that a better understanding of trophic interactions may shed light on the mechanism(s) that facilitate the persistence of native species in the presence of invasive species.

Table 3.3. Size-dependent impacts of western mosquitofish, Gambusia affinis and eastern mosquitofish, G. holbrooki (indicated with †) on native fish species. Approach code: ME = mesocosm experiments, FO = field observations, LE = laboratory experiments, FE = field experiments, FS = field surveys.

Species impacted Mosquitofish interaction(s) Negative Maximum Approach Reference with native fish species Impact Body size (mm) 1 Dwarf livebearer† Significant negative effect of Yes 36 ME Lydeard & Belk 1993 Heterandria formosa population growth 2 Dwarf livebearer† Size selective predation on small Yes 36 ME Belk & Lydeard 1994 H. formosa individuals 3 White Sands pupfish Significant impact on population size Yes 50 ME Rogowski & Cyprinodon tularosa and biomass Stockwell 2006 4

63 Spanish toothcarps† Heavy predation on juveniles Yes 52* ME Rincon et al. 2002

Aphanius iberus and

Valencia hispanica 5 Big Bend gambusia Endangerment of local populations Yes 54 FO Minkley & Deacon 1968 Gambusia gagei 6 Pacific blue-eye† Lack of recruitment and reduced growth Yes 56** ME Howe et al. 1997 Pseudomugil signifer of adults 7 Gila topminnow Rapid replacement from most of its Yes 60 FO Minkley & Deacon 1968 Poeciliopsis occidentalis native range 8 Sonoran topminnow Replacement in native range possibly by Yes 60 LE & FE Meffe 1985 P. occidentalis Predation on of juveniles 9 Sonoran topminnow Population decline by presumed Yes 60 FO & FS Galat & Robertson 1992 P. o. sonorensis mosquitofish predation 10 Least chub Reduction of survival and growth rate of Yes 64 FE Mills et al. 2004 Iotichthys phlegethontis larva/juveniles by predation. 11 Rainbowfish Apparent displacement from native habitat Yes 65** FO Arthington 1984 Rhadinocentris ornatus * Specific maximum body size was extracted from the reference cited; **Pusey et al. 2004, other values according to Page and Burr 1991.

Table 3.3. (continued)

Species impacted Mosquitofish interaction(s) Negative Maximum Approach Reference with native fish species Impact body size (mm) 12 White River springfish Population decline by presumed Yes 90 FB & FS Deacon et al. 1964 Crenichthys baileyi mosquitofish predation Laha and Mattingly 13 Barrens topminnow Reduced survival of larva/juveniles by Yes 94 LE 2007 Fundulus julisia. predation , Injury risk to adults 14 Black mudfish Predation of mudfish larvae Yes 106* LE & FO Barrier and Hicks 1994 Neochanna diversus Overall coexistence may be due to No spatial / temporal habitat partitioning 15 Mohave tui chub Predation of tui chub larvae Yes 300* ME & LE Henkanaththegdara and Siphateles bicolor Predation of mosquitofish by adult tui chubs No Stockwell unpublished mohavensis

64 16 Green sunfish Predation of sunfish larvae Yes 310 FE Blaustein 1991 Lepomis cyanellus Predation of mosquitofish by adult sunfish No 17 Largemouth bass Population reduction of mosquitofish due No 970 FE Nowlin et al. 2006 Micropterus salmoides to predation

Literature Cited

Arim, M. and P.A. Marquet. 2004. Intraguild predation: a widespread interaction related to

species biology. Ecology Letters 7: 557-564.

Bampfylde, C.J. and M.A. Lewis. 2007. Biological control through intraguild predation: case

studies in pest control, invasive species and range expansions. Bulletin of Mathematical

Biology 69: 1031-1066.

Barrier, R.F.G. and B.J. Hicks. 1994. Behavioral interactions between back mudfish (Neochanna

diversus Stokell, 1949: Galaxiidae) and mosquitofish (Gambusia affinis Baird and Girard,

1845). Ecology of Freshwater Fish 3: 93-99.

Belk, M.C. and C. Lydeard.1994. Effects of Gambusia hobrooki on a similar-sized, syntopic

poeciliid, Heterandria formosa: competitor or predator? Copeia 1994: 296-302.

Courtenay, W.R. Jr. and G. K. Meffe. 1989. Small fishes in strange places: A Review of

introduced Poecillids. Pp. 319-333. In. G. K. Meffe and F. F. Snelson, Jr. (editors),

Ecology and Evolution of live-bearing fishes (Poecillidae). Prentice Hall, New Jersey,

NJ, USA.

Diehl, S. 1992. Fish Predation and Benthic Community Structure: The Role of Omnivory and

Habitat Complexity. Ecology 73: 1646-1661.

Hambright, K.D. 1991. Morphological constraints in the piscivore-planktivore interactions:

Implications for the trophic cascade hypothesis. Limnology and Oceanography 39: 897-

912.

Hambright, K.D., R.W. Drenner, S.R. McComas, and N.G. Hairstone. 1991. Gape-limited

piscivores, planktivore size refuges, and the trophic cascade hypothesis. Archiv fur

Hydrobiologie 121: 389-404.

Henkanaththegedara, S.M. and C.A. Stockwell. In review. Reciprocal Predation Mediates Co-

existence of Native and Non-native Fish. Conservation Biology.

Holt, R.D. and G.A. Polis. 1997. A Theoretical Framework for Intraguild Predation. The

American Naturalist 149:745-764.

Hughes, A. L. 1986. Growth of adult mosquitofish Gambusia affinis in the laboratory. Copeia

1986: 534-536.

Ling, N. 2004. Gambusia in New Zealand: really bad or just misunderstood? New Zealand

Journal of Marine and Freshwater Research 38: 473-480.Magnhagen, C. and E. Heibo.

2001. Gape size allometry in pike reflects variation between lakes in prey availability and

relative body depth. Functional Ecology 15: 754-762.

Maindonald, J. and W.J. Braun. 2010. Data analysis and graphics using R: An example-based

approach (3rd edition). Cambridge University Press.

Meffe, G. K. 1985. Predation and species replacement in American southwestern fishes: a case

study. Southwestern Naturalist 30: 173-187.

Mills, M. D., R. B. Rader and M.C. Belk. 2004. Complex interactions between native and

invasive fish: the simultaneous effects of multiple negative interactions. Oecologia 141:

713-721.

Nilsson, P.A. and C. Bronmark. 2000. Prey vulnerability to a gape-size limited predator:

behavioural and morphological impacts on northern pike piscivory. Oikos 88: 539-546.

Nilsson, P.A., C. Bronmark, and L.B. Pettersson. 1995. Benefits of predator induced morphology

in crucian carp. Oecologia 104: 291-296.

Nowlin, W. H., R. W. Drenner, K.R. Guckenberger, M.A. Lauden, G.T. Alonso, et al. 2006.

Gape limitation, prey size refuges and the top-down impacts of piscivorous largemouth

bass in shallow pond ecosystems. Hydrobiologia 563:357–69

Page, L.M. and B.M. Burr. 1991. A Field Guide to Freshwater Fishes: North America North of

Mexico. Houghton Mifflin Company, Boston.

Phillips, B. L. and R. Shine. 2004. Adapting to an invasive species: Toxic cane toads induce

morphological change in Australian snakes. Proceedings of National Academy of Science

101: 17150–17155

Polis, G.A. and R.D. Holt. 1992. Intraguild predation: The dynamics of complex trophic

interactions. Trends in Ecology and Evolution 7: 151-154.

Polis, G.A., C.A. Myers, and R.D. Holt. 1989. The ecology and evolution of intraguild predation:

potential competitors that eat each other. Annual reviews of Ecology and Systematics 20:

297-330.

Post, D.M., E.P. Palkovacs, E.G. Schielke, and S.I. Dodson. 2008. Intraspecific variation in a

predator affects community structure and cascading trophic interactions. Ecology 89:

2019-2032.

R Development Core Team (2010). R: A language and environment for statistical computing. R

Foundation for Statistical Computing, Vienna, Austria. http://www.R-project.org.

Reznick, D. A., H. Bryga and J. A. Endler. 1990. Experimentally induced life-history evolution

in a natural population. Nature 346:357 – 359.

Rincon, P.A., A.M. Correas, F. Morcillo, P. Risueno and J. Lobon-Cervia. 2002. Interaction

between the introduced eastern mosquitofish and two autochthonous Spanish toothcarps.

Journal of fish biology 6: 1560-1585.

Rogowski, D.L. and C.A. Stockwell. 2006. Assessment of Potential Impacts of Exotic Species

on Populations of a Threatened Species, White Sands Pupfish, Cyprinodon tularosa.

Biological Invasions. 8: 79-87.

Sih, A., P. Crowley, M. McPeek, J. Petranka, and K. Dtrohmeier. 1985. Predation, Competition,

and Prey Communities: A Review of Field Experiments. Annual Reviews of Ecology and

Systematics 16: 269-311.

Stibor, H. 1992. Predator induced life-history shifts in a freshwater cladoceran. Oecologia

92: 162-165, DOI: 10.1007/BF00317358

Stockwell, C.A. and S.M. Henkanaththegedara. 2011. Evolutionary Conservation Biology of

Poeciliids. In. Evan, J., A. Pilastro and I. Schlupp (editors). Ecology and Evolution of

Poeciliid Fishes. University of Chicago Press. Chicago.

Taniguchi, Y., K.D. Fausch, and S. Nakano. 2002. Size-structured interactions between native

and introduced species: can intraguild predation facilitate invasion by stream salmonids?

Biological Invasions 4:223–233.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. United States Fish and Wildlife Service, Portland, Oregon.

Therneau, T and T. Lumley. 2009. survival: Survival analysis, including penalised likelihood. R

package version. 2.35-8. http://CRAN.R-project.org/package=survival

Warren, P.H. and J.H. Lawton. 1987. Invertebrate predator-prey body size relationships: an

explanation for upper triangular food webs and patterns in food web structure? Oecologia

74 231-235.

Webb, J.K. and R. Shine. 1993. Prey-size selection, gape limitation and predator vulnerability in

Australian blindsnakes (Typhlopidae). Animal Behaviour 45: 1117-1126.

CHAPTER 4. CONSERVATION TRANSLOCATIONS BENEFIT

PROTECTED FISH, BUT MAY IMPACT ENDEMIC INVERTEBRATES*

To be submitted to Diversity and Distributions as: Sujan Henkanaththegedara1, Justin Fisher1,

Daniel McEwen2, and Craig Stockwell1. Conservation translocations benefit protected fish, but may impact endemic invertebrates.

1 Environmental and Conservation Sciences Graduate Program, Department of Biological

Sciences, North Dakota State University Dept. 2715, P.O. Box 6050, Fargo ND 58108-6050.

2 Biosciences Department, Minnesota State University Moorhead, 1104 7th Avenue South,

Moorhead MN, 56563.

Abstract

Desert springs, which harbor diverse and endemic invertebrate assemblages, are often used as refuge habitats for protected fish species. Additionally, non-native fish species often invade desert springs. The impact of recently established fish populations on the unique invertebrate communities has not received much attention. We conducted a mesocosm experiment to assess the impact of both protected and invasive fish species on community structure of spring-dwelling invertebrates. Invertebrate communities were established in large mesocosms with one of four treatments: 1) fishless, 2) invasive western mosquitofish, Gambusia affinis 3) endangered Mohave tui chub, Siphateles bicolor mohavensis and 4) both fish species in

* The material in this chapter was co-authored by Sujan Henkanaththegedara, Justin Fisher, Daniel McEwen, and Craig Stockwell. Henkanaththegedara and Stockwell conceived and designed the experiments. Henkanaththegedara and Fisher performed the experiments. Henkanaththegedara analyzed the data with assistance from McEwen. Stockwell served as proofreader and checked the statistical analysis conducted by Henkanaththegedara.

70 sympatry. Final populations of invertebrates and fish were sampled, sorted, identified and counted after 67 days. Heterogeneity of the invertebrate communities and densities of major invertebrate taxa were compared among the four treatments. The diversity of invertebrate communities in experimental mesocosms was negatively impacted by the presence of fish.

Further, model selection also showed a negative association between fish and invertebrates.

Invertebrate community structure changed mainly due to population declines and local extirpations of invertebrates, presumably due to fish predation. In fish treatments, densities of crustaceans and chironomid larvae dropped and cladocerans were virtually eliminated. An

NMDS analysis showed a strong disassociation of the majority of invertebrate taxa among the different fish treatments. Native protected fish transplanted to fishless desert springs may also have negative impacts on unique spring-dwelling invertebrate communities, in addition to widespread invasive fish species. Therefore, invertebrate communities should be surveyed when desert springs are evaluated as potential refuge habitats for protected fish species translocations.

Introduction

Desert springs function as “keystone” ecosystems playing a major role in evolutionary process and regional biodiversity (Stevens and Meretsky 2008). In arid regions of the southwestern United States, these patchily distributed springs harbor highly diverse faunal assemblages, especially fish, mollusks and aquatic insects (Soltz and Naiman 1978, Shepard

1993, Sada and Vinyard. 2002). Furthermore, desert springs host the highest number of endemic taxa in North America (Stevens and Meretsky 2008) making them one of the conservation priorities of the region (Williams et al. 1985; Shepard 1993).

Recent studies have uncovered unique, highly diverse and endemic macro-invertebrate assemblages from these desert springs (Hershler and Sada 1987, 2002; Shepard 1990; Polhemus and Polhemus 2002). Despite their ecological and evolutionary importance, most of these invertebrate taxa are poorly studied (Williams et al. 1985; Sada and Vinyard. 2002) and threatened with extinction risk due to anthropogenic impacts (Shepard 1993; Unmack and

Minckley 2008). For an example, 13 new Cochliopid spring snails have been recently discovered from Chihuahua Desert; however, two of these species were extinct prior to formal description (Hershler et al. 2011). Major threats for desert springs and their fauna include water mining, habitat alterations, and introduction of non-native species (Williams et al. 1985; Shepard

1993; Unmack and Minckley 2008).

Many desert springs have been stocked with non-native fish (Pister 1974; Unmack and

Minckley 2008) to control mosquito-borne diseases (western mosquitofish Gambusia affinis;

Meffe 1985), promote sport fishing (large-mouth bass Micropterus salmoides; Soltz and Naiman

1978), as breeding ponds for aquarium fish (sailfin molly Poecilia latipinna; Deacon and

Williams 1991) and more recently as refuge habitats for protected fish species (Hendrickson and

Brooks 1991; Minckley 1995; Hendrickson and Minckley 1985). Collectively, many non-native fish introductions to desert springs have negatively impacted native fish populations, sometimes leading to their extirpations (Pister 1974; Moyle 1976; Soltz and Naiman 1978).

Virtually all work concerning fish impacts on invertebrate communities has focused on the effects of invasive mosquitofish (Gambusia affinis and G. holbrooki). The impact of invasive mosquitofish on invertebrate communities has been documented from many aquatic systems (Hurlbert et al. 1972; Englund 1999; Angeler et al. 2002; Pyke 2008; Stockwell and

Henkanaththegedara 2011). Hurlbert et al. (1972) reported elimination of cladocera and

72 significantly reduced densities of rotifers, crustaceans and aquatic insects in experimental mesocosms as a result of predation by western mosquitofish (G. affinis). Further, Linderiella occidentalis, a fairy shrimp species, endemic to California vernal pools, had lower survival in experimental ponds sympatric with western mosquitofish compared to control ponds (Leyse et al. 2004). However, very little work has been conducted on the impacts of fish introductions on aquatic invertebrate communities in desert spring systems (Pister 1974; Moyle 1976; Soltz and

Naiman 1978).

In addition to non-native fish, protected native fish species have also been transplanted to desert springs as a widely practiced conservation management strategy (Hendrickson and Brooks

1991; Minckley 1995; Hendrickson and Minckley 1985). Twenty four endemic fish species in the Great Basin have been transplanted to aquatic systems within and outside of their historic range (Sada and Vinyard 2002). In fact, managers actively transplanted endangered Gila topminnow (Poeciliopsis occidentalis occidentalis) in to natural springs and ciénegas during vigorous reintroductions in the 1960s and 1970s (Hendrickson and Minckley 1985; Hendrickson and Brooks 1991). Likewise, endangered Mohave tui chub (S. b. mohavensis; Miller 1968;

Hoover and St. Amant 1983) and Pahrump poolfish (Empetrichthys latos latos; Shawn

Goodchild Personal Communication) were transplanted to fishless springs as a strategy to increase the security of these fish species. Such conservation transplants have successfully reduced extinction probability for many protected fish species (Minckley 1995; Johnson and

Hubbs 1989; Hendrickson and Brooks 1991), but these activities may have unexpected negative impacts on spring-dwelling native invertebrates. In addition to spring habitat modifications (e.g. damming to create pools) to create secure refuges for protected native fish (Shepard 1993;

Hershler 1989), direct predation by newly established fish populations may have negative impacts on spring-dwelling invertebrate communities.

To our knowledge, the potential impact of fish on spring-dwelling invertebrate communities has never been quantified with controlled experiments. Previously, we used mesocosm experiments (Stockwell and Henkanaththegedara 2011, Henkanaththegedara and

Stockwell unpublished data) to evaluate the interactions between the protected Mohave tui chub

(S. b. mohavensis) and invasive western mosquitofish (G. affinis). Here we take advantage of this experiment to contrast the invertebrate communities of mesocosms with experimental fish populations to a series of fishless control mesocosms, established simultaneously. This experimental approach allowed us to gain valuable insights to the potential impacts of fish introductions on spring-dwelling invertebrate assemblages.

Methods

Study System

The Mohave tui chub is endemic to the Mojave River Drainage (Hubbs and Miller 1943) and it was restricted to deep pools of the main stream Mojave River and at least one land locked refuge population close to Soda Dry Lake (i.e. Zzyzx), the terminal sink of the Mojave River

(Miller 1938). However, the river populations have extirpated by late 1960’s (Miller 1969). A series of transplant attempts was initiated in early 1950’s to reduce the extinction risk of the

Mohave tui chub (Miller 1968; Hoover and St. Amant 1983). Nevertheless, only China Lake and

Camp Cady populations survived to-date. As a result of its very restricted range and potential impacts of non-native species, the Mohave tui chub was listed as a federally endangered species

(U.S. Fish and Wildlife Service 1984).

Zzyzx has several desert springs of which, two harbor populations of the endangered

Mohave tui chub (Siphateles bicolor mohavensis). The larger tui chub population co-habits Lake

Tuendae with the invasive western mosquitofish (Gambusia affinis) and a small population of

Saratoga Springs pupfish (Cyprinodon nevadensis nevadensis). Lake Tuendae is a highly modified desert spring (Turner and Liu 1976) approximately 140 × 40 m in size with a maximum depth reaching about 2 m. The other Zzyzx tui chub population inhabits a relatively small spring called MC Spring (4 × 5 m and approximately 1 m deep), approximately 300 m south of Lake

Tuendae.

Recently the interest in Mohave tui chub was sparked by the discovery of western mosquitofish at Lake Tuendae in 2001 (Steve Parmenter personal communication), leading managers to recommend research concerning the effects of mosquitofish on Mohave tui chub and to more aggressively pursue recovery of the Mohave tui chub (U.S. Fish and Wildlife

Service 1984; Hughson and Woo 2004). The down-listing of the Mohave tui chub requires the establishment of additional populations, making an overall of 6 geographically isolated self- sustaining populations with 500 breeding fish for 5 years (U.S. Fish and Wildlife Service 1984).

Nevertheless, potential aquatic habitats as refuges are limited in desert ecosystems and some have previously been invaded by mosquitofish. Recent findings that Mohave tui chub may be able to co-persist with mosquitofish (Stockwell and Henkanaththegedara 2011;

Henkanaththegedara and Stockwell unpublished data), led managers to introduce tui chubs to

Deppe Pond in 2008, a site inhabited by western mosquitofish (Matt Huffine and Steve

Parmenter personal communications). With this recent transplant, Mohave tui chub currently occupies five habitats, and co-occurs with western mosquitofish in three of these habitats.

However, two additional populations of Mohave tui chub need to be successfully established for the recovery.

Experimental Setup

We conducted a mesocosm experiment mimicking the spring environment in large mesocosms. Mesocosms were deployed at the Desert Studies Center at Zzyzx, California from 8

March 2009 to 12 May 2009. Thirty five large circular mesocosms were employed to host experimental populations of aquatic invertebrates in the absence and presence of Mohave tui chub and/or western mosquitofish. At the onset of experiment, mesocosms were filled with water from Lake Tuendae to introduce invertebrate communities, but filtered through 1.18 mm mesh to exclude larval fish (may have excluded some macro-invertebrates too). Each tank was provided with a constant aeration system, equal amounts of plastic “plants” to provide cover and substrate, and poultry fence to exclude avian predators.

The mesocosms were randomly assigned to one of three fish treatments each with 10 replicates: allopatric Mohave tui chubs (MTC); allopatric western mosquitofish (WMF); and

Mohave tui chubs sympatric with western mosquitofish (MTC + WMF). Lastly, the remaining five mesocosms were left fishless as controls. The thirty mesocosms hosting fish populations and two of the fishless mesocosms were established in tanks with a diameter of 1.8 m (volume ~

1.2 m3), but the three other fishless mesocosms were hosted in larger tanks with diameter of 2.5 m (volume ~ 2.6 m3). Because this work focuses on invertebrate densities, the difference in volume was not expected to generate substantive effects. The final invertebrate densities between the large and small tanks, were not significantly different (Wilcoxon rank sum test;

Table 1) indicating the lack of tank size effects on invertebrate densities.

Table 4.1. The final invertebrate densities in small (volume ~ 1.2 m3) and large (volume ~ 2.6 m3) tanks used for fishless control treatment. The averages were tested with Wilcoxon rank sum test for any significant differences.

Invertebrate Average density (per L ± SE) W p-value Group Small tank (n=2) Large tank (n=3) Rotifers 39682.0 (± 20918.0) 63033.3 (± 5068.9) 1.0 0.40 Crustacean nauplii 79.5 (± 2.5) 66.3 (± 3.8) 6.0 0.20 Cladocera 554 (± 58.0) 528.0 (± 42.4) 4.0 0.76 Ostracods 3.5 (± 3.5) 4.0 (± 0.58) 3.0 1.00 Calanoid copepods 41.0 (± 18.0) 50.3 (± 14.2) 2.0 0.80 Cyclopoid copepods 210.0 (± 102.0) 134.3 (± 56.3) 5.0 0.37 Chironomid larvae 6.0 (± 2.0) 3.0 (± 1.5) 4.5 0.55 Water mites 24.0 (± 4.0) 9.0 (± 3.1) 6.0 0.20

This design allowed us to evaluate the impacts of the invasive western mosquitofish

(mimicking fish invasion) as well as endangered Mohave tui chub (mimicking fish transplants) on spring-dwelling invertebrate communities. In addition, the sympatric treatments allowed us to understand the combined effect of both invasive and native fish species on invertebrates, which represents the contemporary conditions of many desert springs.

Tanks were stocked with adult Mohave tui chubs and mosquitofish captured from Lake

Tuendae using minnow traps and hand nets. Mesocosms receiving Mohave tui chubs (MTC and

MTC+WMF) were each stocked with 8 adult Mohave tui chubs of typical size range (80-120 mm). Mesocosms receiving mosquitofish (WMF and MTC+WMF) were each stocked with 25 male and 50 female mosquitofish. Relative densities of the two species and the sex ratio of mosquitofish were chosen to reflect relative densities and sex ratios in Lake Tuendae. We did not include Saratoga Springs pupfish, because this species was at very low density when our experiments were conducted. Fish were fed ground pelleted fish food at a ration of 4% of stocked fish biomass per day.

Sampling and Diversity Analysis

Upon conclusion of the experiment, aquatic invertebrates were collected using a 2.0 L

Van Dorn type horizontal water sampler. Two water samples, one close to the surface and the other close to the bottom, were collected from each mesocosm and filtered through a 65 μm mesh net funnel to recover invertebrates. The recovered material was fixed in 10% sugar- formalin (Lind 1985) and a drop of Rose-Bengal stain (stains animal proteins in red) was added to each vial before laboratory analysis to enhance the visibility. All surviving fish including larval stages were collected and enumerated by seining each tank 5 times and then filtering all tank water through a fine mesh net.

In the laboratory, samples were filtered through a 65 μm mesh net funnel again and the materials were suspended in 50 ml of water. Suspended invertebrates were sub-sampled (5.0 ml) five times and counted using a counting wheel under a stereo-microscope. Invertebrates were identified to major taxonomic levels using identification keys provided by Pennak (1989). We restricted our analysis only to the invertebrate taxa which had a cumulative sum of more than 2 individuals (i.e. rotifera, cladocera, ostracoda, calanoid copepods, cyclopoid copepods, chironomid larvae, hydracarina and crustacean nauplii) due to extreme rarity of such taxa and to avoid associated zero truncation problem where absence of a particular taxa (zeros) may constrain the analysis (Beals 1984).

Invertebrate densities were converted to number per liter before analyses. The diversity of invertebrate communities of different treatments was estimated with Shannon-Weiner

Diversity Index (H’; Krebs 1999). Where, pi = Proportion of species i in the community.

s H'  - p log p  ii 2  i 1

Fish Diet Analysis

We examined diet for 30 adult Mohave tui chubs and 30 adult western mosquitofish which were collected simultaneously from Lake Tuendae in February 2008. The biomass of tui chub (nearest 0.1 g) and mosquitofish (nearest 0.0001 g) were obtained using digital scales and the entire gastrointestinal tract was extracted. Contents from the first 1/3 of the gut was removed, sorted, identified to the lowest possible taxa using standard keys and counted

(Numerical Method; Windell 1968). This analysis was restricted to the same invertebrate taxa considered for the mesocosm experiments for comparative purposes and due to comparative rarity of other taxa in fish guts. However, amphipods were included for this analysis due to its high abundance in fish guts. Also calanoid and cyclopoid copepods were lumped together (as copepods). The percentage occurrence was estimated by estimating the percentage of all stomachs containing food in which each food category occurred (Wallace 1981). Percentage composition was estimated as the percentage of each food category contributed to the total number of food items in all stomachs by pooling data for all fish (Wallace 1981).

Statistical Analysis

All statistical analyses were conducted using R statistical software program (Version

2.11.0; R Development Core Team 2010). For invertebrate densities and Shannon-Weiner diversity (H’), data were tested for normality with a Shapiro-Wilk normality test (shapiro.test function). Because data were not normally distributed, a Kruskal-Wallis rank sum test

(kruskal.test function) was used to test for treatment effects. Separate tests were run for each invertebrate group using population density as the response variable and treatment as the

79 explanatory variable. Post-hoc analyses were conducted by performing a Tukey HSD test

(TukeyHSD function) on ranked data while maintaining a 0.05 experimental-wise error rate (Zar

2010).

Both number of invertebrates in each gut as well as weighted number of invertebrates were used for the analysis of fish diet. Weighted numbers were estimated to standardize the data by dividing number of invertebrates with fish biomass due to prominent size differences between these fish species. Number of invertebrates and weighted number of invertebrates in guts of tui chub and mosquitofish were compared non-parametrically using Wilcoxon rank sum test

(Wilcox.test function) due to highly skewed nature of these data.

Nonmetric multidimensional scaling (NMDS) was performed to reduce the taxa matrix of eight to two dimensions. The best two-dimensional solution of 10,000 random starts was chosen and we generated the coefficient of determination (R2) of the final simulated distance matrix which was regressed against the actual distance matrix to assess how much of the original distances were preserved in our solution. Stress ~ 0.20 was considered an adequate solution

(McCune and Grace 2002). Because the difference between the most abundant taxa and least abundant taxa was a magnitude of four, the taxa abundances were relativized by the maximum to equalize the impact of individual taxa on the ordination. Final ordination was performed based upon a Bray Curtis distance measure. To show taxa relationships to modeled axes, Pearson

Correlation Coefficients for each taxa against the NMDS axes were generated and showed these as directional vectors on the ordination plot with site scores relativized by their maximum.

The two NMDS axes scores were separately used in a multiple regression along with model selection using the small sample size corrected Akaikie Information Criteria (AICc;

Burnham and Anderson 2002) to determine the best suite of treatment variables influencing the

80 invertebrate community. Six models were determined a priori as follows: (1) null model featuring the simple average as the best predictor, (2) additive factorial model with levels including Mohave tui chubs and mosquitofish, (3) multiplicative factorial model as above but including an interaction between Mohave tui chubs and mosquitofish, (4) factorial design with

“fish” or “no fish” as levels, (5) covariate model with total number of fish as a predictor without respect to species, and (6) a covariate model including numbers of Mohave tui chubs and mosquitofish further delimited into age categories: adult and larvae. The coefficient of determination was generated to determine goodness of fit for the best model on each axis.

Statistical analyses were conducted in R using packages “vegan” and “labdsv”.

Results

The diversity of invertebrate communities in experimental mesocosms was impacted by the presence of fish. The mean heterogeneity (H’) of invertebrate taxa showed significant

2 differences among treatments (X 3=25.56; p < 0.001). Post-hoc pairwise comparisons showed significantly low invertebrate diversity in sympatric fish treatment and allopatric mosquitofish treatment compared to both allopatric tui chub treatment and fishless control. This indicates a clear reduction of invertebrates in the treatments with mosquitofish compared to both treatments with tui chubs and fishless control (Figure 4.1).

Invertebrate community structures also changed mainly due to population declines and local extirpations of invertebrates, presumably due to fish predation. Treatments with fish had lower densities of invertebrates compared to fishless treatment except for rotifers and water mites (Figure 4.2). The density of mature forms and nauplii of crustaceans (except ostracods) and chironomid larvae showed significant differences among treatments (Figure 4.2). For example,

81 smaller bodied-mobile crustaceans (cladocera and crustacean nauplii) had low densities within mosquitofish treatments. Larger bodies-mobile crustaceans (calanoid and cyclopoid copepods) had lower densities in the presence of fish, but the density of these invertebrates did not differ among the three fish treatments. The lowest density of chironomid larvae was reported with allopatric tui chub treatment which is marginally significant (p = 0.060) compared to fishless control (Figure 4.2). The densities of rotifers, ostracods and hydracarina water mites had no significant differences among treatments (Figure 4.2).

NMDS achieved a two-dimensional solution for invertebrate community assemblages with a stress = 0.21 (Figure 4.3). We identify 3 distinct clusters for the allopatric tui chub, allopatric mosquitofish and fishless treatments. The sympatric fish mesocoms containing both tui chubs and mosquitofish are mostly in the upper quadrants but overlap considerably between the allopatric fish treatments as expected (Figure 4.3). All correlation vectors for invertebrate taxa with the exception of rotifers pointed into the lower two quadrants and were strongly associated with experimental units with no fish.

Model selection indicated that the best predictors for the second axis was “fish/no fish” model (Multiple Regression R2adj = 0.75) such that there were more invertebrates where fish did not occur (Table 4.2). The best model selected for the first axis was the multiplicative model that

2 included an interaction between Mohave tui chub and mosquitofish (Multiple Regression R adj =

0.57; Table 4.2). Thus, there were fewer invertebrates overall (i.e., second axis result) in experimental units containing fish, but the invertebrates that were found in these samples tended to clump into two major groups. Benthic invertebrates, including chironomid larvae and water mites were negatively associated with the allopatric tui chub treatments. Crustaceans in the left lower corner of the plot were negatively associated with mosquitofish treatments. Plots with both

82 fish were harder to distinguish based on invertebrate community, suggesting that when both fish species are present they have an effect of increasing diversity; given any measure of diversity that includes evenness.

Table 4.2. Akaikie Information Criteria with the small sample size correction on six candidate models used to model scores from a two-dimensional NMDS ordination. Abbreviations are MF = mosquitofish, MTC = Mohave tui chub, Fish/No Fish = presence or absence of fish, Total Fish = counts of fish present in experimental tanks, and Age Structure = a four parameter model where MF and MTC are further divided into adults and larval fish with counts used as predictors.

Axis 1 Axis 2

Model K ΔAICc wc ΔAICc wc

MF*MTC 5 0.00 0.97 2.42 0.23

MF+MTC 4 12.23 0.00 8.69 0.01

Fish/No Fish 3 21.41 0.00 0.00 0.76

Total Fish 3 26.45 0.00 18.69 0.00

Age Structure 6 7.13 0.03 9.07 0.01

Null 2 39.27 0.00 16.35 0.00

Fish diet analysis provided additional information to understand fish impacts on invertebrates. We did not find any completely empty guts in any of the fish examined. The percentage occurrence of invertebrates differed among invertebrate taxa (Figure 4.4-A). For example, crustacean nauplii were the least commonly observed taxa in both mosquitofish and tui chubs. By contrast, chironomid larvae occurred in 90% of tui chubs and 83% of mosquitofish making it the most common food item in the guts of both fish species (Figure 4.4-A). We found significantly higher numbers of ostracods (w = 589; p = 0.016), chironomid larvae (w = 638.5; p

0.005) and amphipods (w = 693; p < 0.001; Figure 4.4-B) in tui chubs compared to mosquitofish.

By contrast, mosquitofish had significantly higher number of cladocerans (w = 328; p = 0.04),

83 chironomid larvae (w = 163.5; p < 0.001) and amphipods (w = 637; p < 0.01) after adjusting the numbers for fish biomass, indicating unparalleled impact of mosquitofish on invertebrates regardless of its smaller body size (Figure 4.4-C). Furthermore, percentage composition showed the importance of different invertebrate taxa as major food items. Collectively, chironomid larvae represented more than 50% of the food items in both tui chubs and mosquitofish.

Furthermore, mosquitofish had a higher affinity for cladocera (18%) and tui chub for copepods

(34%) followed by chironomid larvae (Figure 4.5).

Figure 4.1. The mean heterogeneity (Shannon-Wiener Index, H’) of aquatic invertebrate 2 diversity was significantly differed among treatments (X 3=25.56; p < 0.001). Treatment codes: MTC+MF = sympatric fish, MF only = allopatric mosquitofish, MTC only = allopatric tui chubs, and NONE = fishless control. Error bars are one standard error. Bars with different letters are significantly different at p = 0.05.

Figure 4.2. Differences in mean density of major invertebrate taxa among treatments. Significant 2 2 differences of mean densities were observed for Nauplii (X 3 = 14.75; p < 0.01), Cladocera (X 3 = 2 2 31.93; p < 0.05), Calanoid copepods (X 3 = 12.75; p < 0.01), Cyclopid copepods (X 3 = 10.61; p 2 < 0.05), and Chironomid larvae (X 3 = 7.83; p < 0.05). Treatment codes: MTC+MF = sympatric fish, MF only = allopatric mosquitofish, MTC only = allopatric tui chubs, and NONE = fishless control. Error bars are one standard error. Bars with different letters are significantly different at p = 0.05. A* indicates marginal significance at p = 0.055.

Figure 4.3. Nonmetric multidimensional scaling plot where points represent experimental units from treatments: Mohave tui chub only (■), mosquito fish only (○), both Mohave tui chub and mosquite fish (×), and no fish ( ). Site scores were relativized by the maximum and vectors represent the Pearson Correlation Coefficients for each taxa included in the ordination. The goodness of fit measure (R2) is for the relationship between the modeled distance matrix and the actual distance matrix. The NMDS was performed on maximum relativized taxa counts and used the Bray Curtis distance measure.

Figure 4.4. The distribution of various invertebrate food items in the guts of tui chubs and mosquitofish (n = 30 each). Percentage occurrence (A), average number of invertebrates (B), and average number of invertebrates adjusted for fish biomass (C). Dark grey and black represent Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis), respectively. Error bars are one standard error. Significance level: * p < 0.05, ** p <0.01, *** p < 0.001.

Figure 4.5. Percentage composition of various invertebrate food items in the guts of Mohave tui chub (A) and mosquitofish (B).

Discussion

This study provided experimental evidence for impacts of fish on spring-dwelling aquatic invertebrate communities, presumably due to predation. Specifically, both fish species reduced the diversity as well as the density of invertebrates, but mosquitofish impacts were more severe.

The substantial impact of mosquitofish on invertebrate communities is consistent with reports from other systems (Hurlbert et al.1972; Englund 1999; Angeler et al. 2002; Leyse et al. 2004).

In fact, diversity as a whole and density of some invertebrates (crustacean nauplii and cladocera) were very low in both allopatric and sympatric mosquitofish treatments (WMF and MTC +

WMF) compared to allopatric tui chub treatment (MTC).

Multivariate community analysis and model-selection also indicated the negative impacts of fish on invertebrate community composition. Fishless mesocosms were positively associated with the majority of invertebrate taxa, while mesocosms with fish were negatively associated

88 with invertebrate density, indicating the negative impacts of fish on invertebrates. The scattered nature of sympatric treatments on the ordination plot may be explained by the varying number of surviving mosquitofish within the sympatric mesocosms (range; 0-39; Henkanaththegedara and

Stockwell unpublished data). Model-selection also produced evidence for fish impacts on invertebrates indicating multiplicative factorial model (MTC*WMF) as the best suite of treatment variables influencing the invertebrate community. Overall, both univariate and multivariate tests supported the negative impacts of fish on aquatic invertebrates.

These results suggest the impacts of invasive mosquitofish as a very effective predator on aquatic invertebrates. The densities of copepods, crustacean nauplii and chironomid larvae were greatly reduced in our experimental mesocosms by the presence of mosquitofish. Further, cladocerans were extirpated in 80% of allopatric mosquitofish mesocosms, while they were not extirpated from any tanks in the other treatments. Fish diet analysis also showed the significant impact of mosquitofish on cladocera, chironomid larvae and amphipods after adjusting for mosquitofish biomass. In fact, mosquitofish is a voracious carnivore fish (Pyke 2005, 2008) and similar impacts on invertebrate communities have been widely reported (Hurlbert et al. 1972;

Hurlbert and Mulla 1981; Bence 1988; Angeler et al. 2002). Elimination of cladocerns from mosquitofish treatments have previously been reported for many other systems (Hurlbert et al.

1972; Hurlbert and Mulla 1981; Angeler et al. 2002). For example, enclosure experiments by

Angeler et al. (2002) reported absence of cladocera in treatments with eastern mosquitofish (G. holbrooki) compared to controls. In addition, western mosquitofish eliminated Daphnia pulex and Ceriodaphnia sp. (cladocera) populations and reduced Diaptomus pallidus (calanoid copepod) and Keratella quadrata (rotifera) populations in experimental ponds (Hurlbert and

Mulla 1981).

This experiment also shows that Mohave tui chub can impact invertebrate communities.

Tui chub presence reduced the densities of cladocera, copepods, crustacean naulpii, and chironomid larvae. The lowest chironomid larval density was reported by allopatric Mohave tui chub treatment and extirpations of chironomids occurred in 60% of allopatric Mohave tui chub mesocosms. This may reflect the selectivity in tui chub predation on chironomids. In fact, diet analysis revealed that 90% of tui chubs in Lake Tuendae contained chironomid larvae as a food item and chironomids represented 52% of food composition (n = 30) , making it a major food item of tui chub diet. Overall, this suggests that native fish transplanted to fishless desert springs have a potential to harm its invertebrate communities.

Some invertebrate taxa such as rotifers, ostracods and hydracarina water mites were not affected by the presence of fish. Previous studies have shown that rotifers can easily escape fish predation as a result of comparatively very small body size (Brooks and Dodson 1965). In fact, we did not observe rotifers in the gut contents of any fish we examined. Additionally, controlled experiments have shown that hydracarina water mites with a red body color were rejected by fish predators presumably due to distastefulness (Kerfoot 1982). In fact, majority of the water bugs recovered had red pigmentation. In the case of ostracods, their densities were low in all treatments.

Regardless of the significant results of this experiment, we acknowledge three limitations of experimental setup. First, as previously mentioned, this experiment was originally designed to evaluate the interactions between protected and invasive fish species. The fishless tanks were not randomly assigned, but represented 5 available tanks that were maintained and monitored in the same fashion as the other tanks. However, it provided a unique opportunity for us to understand fish impacts on aquatic invertebrates. Although we used tanks with two sizes for

90 fishless control treatment, the invertebrate densities did not differ between two tank sizes providing an adequate number of replicates for the fishless control treatment. Second, the spring source for invertebrates (i.e. Lake Tuendae) is not a fishless desert spring. Therefore, the fishless treatments actually provide insights to how invertebrate communities respond to removal of fish.

Third, filtering of water to exclude fish larvae during the establishment of mesocosms may have limited the introduction of larger macro-invertebrates (e.g. odonate nymphs, amphipods) into the mesocosms. However, the water was similarly filtered for the fishless mesocosms and the invertebrate community at Lake Tuendae is dominated by smaller bodied taxa (~98%; Appendix

C). Therefore, filtering of water may have not excluded any abundant invertebrate taxa from the mesocosms. Despite these limitations, our experiment clearly shows how fish presence may affect invertebrate community structure and that these effects may differ based on the particular fish species introduced.

Federal and state agencies focusing on public health (e.g. Vector Control Districts) as well as wildlife conservation (e.g. U.S. Fish and Wildlife Service) identify the fishless water bodies as prime locations for fish introductions due to utterly different reasons. Vector Control

Districts actively spread mosquitofish to fishless water bodies as a biocontrol agent of mosquitoes hoping to control dangerous mosquito-borne diseases such as Malaria and West Nile

(Downs 1991; Duryea et al. 1996; Ghosh and Dash 2007). On the other hand, conservation practitioners promote transplants as a very effective management strategy for the recovery of protected fish species (Williams et al. 1988; Hendrickson and Brooks 1991; Minckley 1995).

The vulnerability of fishless desert springs to fish introductions effectively ignores the inherent ecological and evolutionary value of the unique invertebrate assemblages in these habitats.

Our results take on more importance, when one considers that desert springs often harbor endemic species. Many such endemics have only recently been described (Hershler and Sada

1987, 2002; Shepard 1990; Polhemus and Polhemus 2002) and some were lost prior to formal description (Hershler et al. 2011). Thus, it is quite possible that fish introductions may impact endemic invertebrate species. Thus, fish transplants which are pursued to reduce extinction risk for the targeted fish taxon, may actually reduce global diversity. Therefore a precautionary approach would be to conduct invertebrate surveys before any fish introductions (see Leyse et al.

2004). This may allow managers to identify potential refuge habitats for protected fish transplants as well as appreciate the inherent biodiversity of fishless desert springs.

Literature Cited

Angeler, D.G., M. Álvarez-Cobelas, S. Sánchez-Carrillo and M.A. Rodrigo. 2002. Assessment of

exotic fish impacts on water quality and zooplankton in a degraded semi-arid floodplain

wetland. Aquatic Sciences-research Across Boundaries 64:76-86.

Beals, E.W. 1984. Bray-Curtis ordination: an effective strategy for analysis of multivariate

ecological data. Advances in Ecological Research 14:1-55.

Bence, J.R. 1988. Indirect effects and biological control of mosquitoes by mosquitofish. The

Journal of Applied Ecology 25: 505-521.

Brooks, J.L. and S.I. Dodson. 1965. Body Size, and Composition of Plankton. Science 150:28-

35.

Burnham, K. P. and D. R. Anderson. 2002. Model selection and multimodel inference: a

practical information-theoretic approach. 2nd edition. Springer-Verlag, New York, New

York.

Deacon, J.E. and C.D. Williams.1991. Ash Meadows and the legacy of the Devils Hole pupfish.

Pp. 69-87. In. Minckley, W.L. and J.E. Deacon (editors). Battle against extinction: native

fish management in the American west. The University of Arizona Press, Tucson.

Downs, C.W. 1991. Fishes in California Mosquito Control. California Mosquito and Vector

Control Association, Inc., Sacramento, California.

Duryea, R., J. Donnelly, D. Guthrie, C. O’Malley, M. Romanowski, and R. Schmidt. 1996.

Gambusia affinis effectiveness in New Jersey mosquito control. pp. 95–102. In:

Proceedings of the 83rd Meeting of the New Jersey Mosquito Control Association, Inc.

Englund, R.A. 1999. The impacts of introduced poeciliid fish and Odonata on the endemic

Megalagrion (Odonata) damselflies of Oahu Island, Hawaii. Journal of Insect

Conservation 3:225-243.

Ghosh, S.K. and A.P. Dash. 2007. Larvivorous fish against malaria vectors: a new outlook.

Transactions of the Royal Society of Tropical Medicine and Hygiene 101: 1063–1064.

Hendrickson, D.A. and J.E. Brooks.1991. Transplanting short-lived fishes in North American

deserts: review, assessment, and recommendations. Pp. 283-298. In. Minckley, W.L. and

J.E. Deacon (editors). Battle against extinction: native fish management in the American

west. The University of Arizona Press, Tucson.

Hendrickson, D.A. and W.L. Minckley. 1985. Ciénegas: vanishing aquatic climax communities

of the American Southwest. Desert plants 6:131-175.

Hershler, R. 1989. Springsnails (Gastropoda: Hydrobiidae) of Owens and Amargosa River

(Exclusive of Ash Meadows) Drainages, Death Valley System, California-Nevada.

Proceedings of the Biological Society of Washington 102:176-248.

Hershler, R. and D.W. Sada. 1987. Springsnails (Gastropoda: Hydrobiidae) of Ash Meadows,

Amargosa Basin, California-Nevada. Proceedings of the Biological Society of

Washington 100:776-843.

Hershler, R. and D.W. Sada. 2002. Biogeography of Great Basin aquatic snails of the genus

Pyrgulopsis. Pp. 255-276. In. Heshler, R. et al. (editors). Great Basin Aquatic Systems

History. Smithsonian contributions to the earth science: No. 33.

Hershler, R., H. Liu, and J.J. Landye. 2011. New species and records of springsnails

(Caenogastropoda: Cochliopidae: Tryonia) from the Chihuahuan Desert (Mexico and

United States), an imperiled biodiversity hotspot. Zootaxa, 3001: 1-32.

Hoover, F. and J.A. St. Amant. 1983. Results of Mohave tui chub (Gila bicolor mohavensis) relocations in California and Nevada. California Fish and Game 69:54-56.

Hubbs, C. L. and R. R. Miller. 1943. Mass hybridization between two genera of cyprinid fishes

in the Mohave Desert, California. Papers of the Michigan Academy of Science, Arts and

Letters. 28:343-378.

Hughson, D. and D. Woo. 2004. Report on a workshop to revisit the Mohave tui chub recovery

plan and a management action plan. National Park Service.Hurlbert, S. H., J. Zedler and

D. Fairbanks. 1972. Ecosystem alteration by mosquitofish (Gambusia affinis) predation.

Science 175:639-641.

Hurlbert, S. H., J. Zedler and D. Fairbanks. 1972. Ecosystem alteration by mosquitofish

(Gambusia affinis) predation. Science 175:639-641.

Hurlbert, S.H. and M.S. Mulla. 1981. Impacts of mosquitofish (Gambusia affinis) predation on

plankton communities. Hydrobiologia 83:125-151.

Johnson, J.E. and C. Hubbs.1989. Status and Conservation of Poeciliid Fishes. Pp. 301-317. In:

Meffe G.K. and F.F. Snelson, Jr. (editors) Ecology and Evolution of Livebearing Fishes

(Poeciliidae). Prentice Hall Advanced Reference Series, Prentice Hall Inc., New Jersey.

Kerfoot, W.C. 1982. A question of taste: crypsis and warning coloration in freshwater

zooplankton communities. Ecology 63:538-554.

Krebs, C. 1998. Ecological Methodology. 2nd edition. Addison-Welsey Educational Publishers,

Inc. Melno Park, California.

Leyse, K.E., S.P. Lawler, and T. Strange. 2004. Effects of and alien fish, Gambusia affinis, on an

endemic California fairy shrimp, Linderiella occidentalis: implications for conservation

of diversity in fishless waters. Biological Conservation 118:57-65.

Lind, O. 1985. Handbook of common methods in limnology. 2nd Edition. Kendall/Hunt

Publishing Company, Dubuque, Iowa.

McCune, B. and J.B. Grace. 2002. Analysis of Ecological Communities. MjM Software Design,

Gleneden Beach, Oregon.

Meffe, G. K. 1985. Factors resulting in decline of the endangered Sonoran topminnow

Poeciliopsis occidentalis (Atheriniformes: Poeciliidae) in the United States. Biological

Conservation 25:135-159.

Miller, R.R. 1938. Description of an isolated population of the freshwater minnow Siphateles

mohavensis from the Mohave River basin, California. Pomona College Journal of

Entomology and Zoology 30:65-67.

Miller, R.R. 1968. Records of some native freshwater fishes transplanted in to various waters of

California, Baja California and Nevada. Calif. Fish and Game. 54:170-179.

Miller, R.R. 1969. Conservation of fishes in the Death Valley system in California and Nevada.

Cal-Nevada Wildlife Transactions 1969:107-122.

Minckley, W.L. 1995. Translocation as a tool for conserving imperiled fishes: experiences in

western United States. Biological Conservation 72: 297-309.

Moyle, P.B. 1976. Fish introductions in California: history and impact on native fishes.

Biological Conservation 9:101-118.

Pennak, R.W. 1989. Fresh-Water Invertebrates of the United States: Protozoa to Mollusca, 3rd

Edition. Wiley-Interscience.

Pister, E.P. 1974. Desert fishes and their habitats. Transactions of American Fisheries Society 3:

531-540.

Polhemus, D.A. and J.T. Polhemus. 2002. Basin and ranges: the biogeography of aquatic true

bugs (Insecta: Heteroptera) in the Great Basin. Pp. 235-254. In. Heshler, R. et al.

(editors). Great Basin Aquatic Systems History. Smithsonian contributions to the earth

science: No. 33.

Pyke, G. H. 2008. Plague minnow or mosquitofish? A review of the biology and impacts of

introduced Gambusia species. Annual review of Ecology, Evolution and Systematics.

39:171-191.

R Development Core Team (2010). R: A language and environment for statistical computing. R

Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL

http://www.R-project.org.

Sada, D.W. and G.L. Vinyard. 2002. Anthropogenic changes in biogeography of Great Basin

aquatic biota. Pp. 277-293. In. Heshler, R. et al. (editors). Great Basin Aquatic Systems

History. Smithsonian contributions to the earth science: No. 33.

Shepard, W.D. 1990. Microcylloepus formicoideus (Coleoptera: Elmidae), A new riffle beetle

from Death Valley National Monument, California. Entomological News 101:147-153.

Shepard, W.D. 1993. Desert springs-both rare and endangered. Aquatic Conservation: Marine

and Freshwater Ecosystems 3:351-359.

Soltz, D.L. and R.J. Naiman. 1978. The natural history of native fishes in the Death Valley

System. Natural History Museum of Los Angeles County, Science series 30:1-76.

Stevens, L.E. and V.J. Meretsky. 2008. Springs ecosystem ecology and conservation. Pp. 3-10.

In. Stevens, L.E. and V.J. Meretsky (editors). Aridland springs of North America:

ecology and conservation. Arizona-Sonora Desert Museum Studies in Natural History,

The University of Arizona Press, Tucson.

Stockwell, C. A. and S. M. Henkanaththegedara. 2011. Evolutionary conservation biology of

Poeciliids. Pages 128-141 in J. Evan, A. Pilastro and I. Schlupp, editors. Ecology and

Evolution of Poeciliid Fishes. University of Chicago Press. Chicago.

Turner, B.J. and R. K. Liu. 1976. The specific identity of the introduced pupfish at Zzyzx Spring,

California. Copeia 1976:211-212.

Unmack, P.J. and W.L. Minckley. 2008. The demise of desert springs. Pp. 11-34. In. Stevens,

L.E. and V.J. Meretsky (editors). Aridland springs of North America: ecology and

conservation. Arizona-Sonora Desert Museum Studies in Natural History, The University

of Arizona Press, Tucson.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. U.S. Fish and Wildlife Service, Portland, Oregon.

Wallace, R.K. 1981. An assessment of diet overlap indexes. Transactions of the American

Fisheries Society 110:72-76.

Williams, J.E., D.B. Bowmen, J.E. Brooks, A.A. Echelle, R.J. Edwards, D.A. Hendrickson, and

J.J. Landye. 1985. Endangered aquatic ecosystems in North American deserts with a list

of vanishing fishes of the region. Journal of the Arizona-Nevada Academy of Science

20:1-61.

Williams, J.E., D.W. Sada, and C.D. Williams et al. 1988. American Fisheries Society guidelines

for introduction of threatened and endangered fish. Fisheries 13:5-11.

Windell, J.T. 1968. Food analysis and rate of digestion, In. Ricker, W.E. (editor). Methods for

assessment of fish production in freshwaters. IBP handbook No. 3. International

Biological Program/ Blackwell Scientific Publications.

Zar, J.H. 2010. Biostatistical Analysis (5th edition). Prentice Hall Inc., Upper Saddle River, New

Jersey.

CHAPTER 5. GENERAL CONCLUSIONS

Non-native species invasion is an unavoidable global crisis (Elton 1958; Sax et al. 2005;

Davis 2011). In fact, invaded ecosystems are the norm rather than the exception in our contemporary world (Bull and Courchamp 2009; Davis 2011). In most invaded systems, invasive species taken the ecological roles of some native species, establishing complex interactions between native and non-native species (Zavaleta et al. 2001; Bull and Courchamp 2009). One of the main reasons for the failure of invasive species management programs is lack of understanding of complex ecological interactions between native and non-native species in invaded systems (Bull and Courchamp 2009). Therefore it is worth exploring ecological interactions between native and non-native species as it may provide novel insights to invasive species management.

Impacts of invasive mosquitofish (Gambusia affinis and G. holbrooki) on native aquatic organisms and ecosystems are widely reported and often detrimental (Pyke 2008; Stockwell and

Henkanaththegedara 2011). However, in some instances, non-native mosquitofish co-persist with native fish species’ providing opportunities to explore underlying mechanisms. Such is the case with endangered desert fish, Mohave tui chub (Siphateles bicolor mohavensis), where this native minnow co-persists with western mosquitofish (G. affinis) in three of the five refuge populations of tui chubs. Mesocosm experiments reported in Chapter 2 revealed tui chub predation on adult and juvenile mosquitofish, while mosquitofish preyed on eggs and larvae of tui chubs. This case of intraguild predation between tui chubs and mosquitofish appeared size- structured, because male mosquitofish, the smaller sex of this dimorphic species, had very low survival compared to female mosquitofish. This experimental work provided experimental evidence for intraguild predation between native and non-native fish species. Thus, intraguild

100 predation may be an important mechanism facilitating the co-persistence of these two fish species. Furthermore, these findings have led managers to consider habitats currently harboring mosquitofish as possible refuge sites for Mohave tui chub, an option previously un-available.

Previous mesocosm experiments provided some evidence for size-structured intraguild predation between tui chubs and mosquitofish. In Chapter 3, I explored the role of predator gape-limitation in intraguild predation between tui chubs and mosquitofish. The differential predation by male and female mosquitofish on tui chub larvae, and tui chub male-biased predation on mosquitofish, were consistent with the gape-size limitation hypothesis. Further, a literature review showed mosquitofish impacts have been limited to fishes with relatively smaller body sizes. My results suggest that a better understanding of trophic interactions may shed light on the mechanism(s) that facilitate the persistence of native species in the presence of invasive species.

Another important aspect of ecological complexity of non-native species is the impacts of recently established fish populations on unique aquatic invertebrate assemblages in fishless desert water bodies. Recent surveys were shown extremely high diversity and endemism of desert spring invertebrate communities (Hershler and Sada 2002; Polhemus and Polhemus 2002).

These fishless water bodies are often used as refuge habitats for protected fish species, but the impact of such management actions has not received much attention. In Chapter 3, I explored the potential impacts of both protected (Mohave tui chub) and invasive fish (western mosquitofish) species on aquatic invertebrate community structure. The diversity of invertebrate communities in experimental mesocosms was negatively impacted by the presence of fish, presumably due to fish predation. My results suggested that both invasive fish species and protected fish species can

101 impact the structure of invertebrate communities in desert springs. Therefore a precautionary approach would be to conduct invertebrate surveys before any fish introductions.

In summary, my research explored ecological complexity of non-native species impacts on native species. These findings provide some novel insights to the management of desert aquatic ecosystem. Better understanding of complex ecological interactions between native and non-native species may provide alternative management options (e.g. consider habitats with invasive species as refuges for protected species) allowing managers to allocate resources to other threats. Furthermore, managers can maximize overall biodiversity of a managed system by taking a more cautionary, whole ecosystem approach to managing desert springs.

Literature cited

Bull, L.S. and F. Courchamp. 2009. Management of interacting invasives: ecosystem

approaches. Pp. 232-247. In. Clout, M.N. and P.A. Williams (editors) Invasive species

management: A handbook of principles and techniques. Oxford University Press, New

York.

Courchamp, F., J. Chapuis, and M. Pascal. 2003. Mammal invaders on islands: impact, control

and control impact. Biological Reviews 78:347–383.

Davis, M.A., et al. 2011. Don't judge species on their origins. Nature 474:153–154.

Elton, C.S. 1958. The ecology of invasions by animals and plants. Methuen & Co., London.

Hershler, R. and D.W. Sada. 2002. Biogeography of Great Basin aquatic snails of the genus

Pyrgulopsis. Pp. 255-276. In. Heshler, R. et al. (editors). Great Basin Aquatic Systems

History. Smithsonian contributions to the earth science: No. 33.

102

Polhemus, D.A. and J.T. Polhemus. 2002. Basin and ranges: the biogeography of aquatic true

bugs (Insecta: Heteroptera) in the Great Basin. Pp. 235-254. In. Heshler, R. et al.

(editors). Great Basin Aquatic Systems History. Smithsonian contributions to the earth

science: No. 33.

Pyke, G.H. 2008. Plague Minnow or Mosquito Fish? A Review of the Biology and Impacts of

Introduced Gambusia Species. Annual Review of Ecology, Evolution, and Systematics

39:171-191.

Sax, D.F., J.J. Stachowicz and S.D. Gaines (editors). 2005. Species Invasions: Insights in to

ecology, evolution, and biogeography. Sinauer Associates, Inc. Publishers,

Massachusetts.

Stockwell, C.A. and S.M. Henkanaththegedara. 2011. Evolutionary Conservation Biology of

Poeciliids. In. Evan, J., A. Pilastro and I. Schlupp (editors). Ecology and Evolution of

Poeciliid Fishes. University of Chicago Press. Chicago.

103

APPENDIX A. LIFE HISTORY OF ENDANGERED MOHAVE TUI CHUB

Background

Life history and demographic data are very important in conservation management of endangered species. Nevertheless, these data are lacking or poorly documented for majority of protected taxa (Heppell 1998). Life history theory predicts trade-offs in energy allocation

(growth, reproduction, maintenance) based on the differential survival of various developmental stages (Roff 1992). For example, the differences of life history traits such as offspring size and number, size and age at maturity, and reproductive allotment may vary depending on factors such as resource availability and/or predation pressure (Reznick et al. 1990; Roff 1992). The

Mohave tui chub recovery plan (U.S. Fish and Wildlife Service 1984) and management action plan (Hughson and Woo 2002) accentuate the importance of obtaining demographic and life history information for all Mohave tui chub populations to better inform conservation management of this endangered species. However, the life history of endangered Mohave tui chub (Siphateles bicolor mohavensis) has been poorly studied with most previous work limited to only the Lake Tuendae population (Vicker 1973). I studied life history of this endangered fish species and here provide data on age structure, reproductive biology and the diet of four of five extant populations of Mohave tui chub.

Fish Sampling

Mohave tui chubs were sampled from Lake Tuendae, MC Spring, Camp Cady, and China

Lake in 2008 for life history descriptions (age structure, reproductive biology and fish diet). Up to 30 Mohave tui chubs from each population were collected using baited minnow traps (Table

104

A.1). At China Lake, 10 individuals each from G1 Channel, North Channel and George Channel were collected. Furthermore, 30 additional fish were collected from Camp Cady in 2007 for preliminary work on fish aging. All fish were sacrificed using a lethal dosage of MS-222

(500mg/L) and fixed in 10% formalin. Mohave tui chubs were measured for total length (to the nearest 0.01 mm) and wet mass (to the nearest 0.1 g).

Table A.1. Size of Mohave tui chubs (Siphateles bicolor mohavensis) used for life history descriptions in 2008. SE represents one standard error.

Population N Date Total length (mm) Wet mass (g) collected Mean (± SE) Range Mean (± SE) Range MC Spring 25 4/25-26/08 78.90 (± 2.64) 62.71 - 111.05 6.45 (± 0.86) 2.5 - 20.9

Lake Tuendae 30 2/13/2008 124.20 (± 2.33) 95.00 - 143.00 25.18 (± 1.38) 9.7 - 37.9

Camp Cady 30 4/3/2008 109.19 (± 3.84) 68.39 - 150.85 17.06 (± 2.04) 4.6 - 46.9

China Lake 30 4/22-24/08 110.80 (± 2.97) 83.87 - 142.09 19.51 (± 1.54) 7.4 - 38.2

Fish Age Structure

Scales, vertebrae, otoliths, and opercula from 30 Mohave tui chubs collected in 2007 from Camp Cady (TL: 89-130 mm) were extracted for preliminary examination. Scale impressions were prepared on acetate slides using an Ann Arbor Roller Press. Vertebrae were air dried and connective tissues were removed as much as possible. Otoliths were mounted on glass slides and prepared for inspection using 320 and 600 grit sand paper to obtain a smooth cross section through the focus. Opercula were boiled for 1 minute and connective tissues were removed (Crain and Corcoran 2000). For 2008 samples, only opercula (Figure A.1) were used

105 for aging tui chubs (Table A.1). Two independent readers read all structures and any discrepancies were resolved by joint examination.

Figure A.1. Annual growth rings visible on an operculum of Mohave tui chub (Siphateles bicolor mohavensis). Insert shows the full operculum with the magnified area highlighted (Photo: Sujan Henkanaththegedara).

We assumed that otoliths would provide more accurate age estimates because they have been previously validated for other fish species (Beamish and McFarlane 1987; Quist et al.

2007). For Camp Cady fish (collected in 2007), otolith age estimates varied from 5-16 years, where scale age estimates varied only from 1-4 years for the same fish. Therefore, scale age underestimates the fish age by 2-14 years, compared to otolith age. Additionally, Vertebrae age over- or underestimates the age by 4-8 years compared to otolith age. However, opercula age closely matched with the otolith age (Figure A.2). Other workers have also reported scales to underestimate fish ages (Beamish and McFarlane 1987; Scoppettone 1988). Furthermore, Eagle

Lake tui chub (Siphateles bicolor spp.), a closely related subspecies to Mohave tui chub, was

106 aged up to 35 years by opercula readings while maximum age determined by scales was only 8 years (Crain and Corcoran 2000).

Figure A.2. Age bias plot of Mohave tui chub (Siphateles bicolor mohavensis) for ages determined from scales (A) and opercula (B) compared to otolith ages. Dotted line indicates the theoretical 1:1 agreement line of age estimates.

Based on the 2007 Camp Cady analysis, I examined fish age using opercula for four populations of Mohave tui chub collected in 2008. China Lake fish lack or had only poorly

107 defined annual rings on opercula suggesting a stable environment. Therefore, we could not age

China Lake fish. The age distribution varied among MC Spring, Lake Tuendae and Camp Cady, collectively representing age classes from 1 – 18 years. MC Spring fish appear to be short-lived

(1-8 years) compared to Lake Tuendae and Camp Cady fish. Camp Cady fish ages varied from

3-13 years, while Lake Tuendae fish ages varied from 8-14 years (Figure A.3).

Previous work on Lake Tuendae tui chubs based on fish scales reported fish age classes only up to 4 years (Vicker 1973; Taylor and McGriff 1985). However, my results suggest that

Mohave tui chub is a long-lived desert fish species and question the validity of the ages derived from scales (Vicker 1973; Taylor and McGriff 1985).

0.35 Tuendae 0.30 MC Spring

0.25 Camp Cady 0.20

0.15

Frequency 0.10

0.05

0.00 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Opercula age (years)

Figure A.3. Frequency of Mohave tui chub (Siphateles bicolor mohavensis) age based on opercula from Lake Tuendae (N = 29), MC Spring (N = 24) and Camp Cady (N = 30).

108

Reproductive Biology

Preserved tui chub specimens (Table A.1) were carefully inspected for secondary sexual characteristics to establish any sexual dimorphism before dissections. The gonads were extracted and excess moisture was removed using paper towels and weighed to the nearest 0.0001 g

(Denver Instrument Company; model A-250). The gonado-somatic index (GSI) was estimated using following formula for each fish in order to assess variation in reproductive allotment within and among populations (Cailliet et al. 1986).

Gonado-somatic index (GSI) = (gonad weight/ body weight) x 100

Fecundity of mature females was estimated by gravimetric method (Cailliet et al. 1986). A subsample of up to 100 eggs was separated and weighed to the nearest 0.0001 g (Denver

Instrument Company; model A-250). The fecundity was estimated using the following formula.

Fecundity = weight of the subsample x total gonad weight number of eggs in the subsample

Ten separate mature eggs from each mature female were randomly selected and measured for the egg diameter to the nearest 0.01 mm under a 10X dissection microscope. The same 10 eggs were placed on a paper towel to remove excess moisture and weighed to the nearest 0.0001 g (Denver

Instrument Company; model A-250) and the typical egg mass was estimated by calculating the average of ten eggs.

Differences of GSI of Mohave tui chubs were non-parametrically compared between habitats using Kruskal-Wallis rank sum test (function kruskal.test), using GSI as the response variable and habitat as the predictor variable. The fecundity was regressed against the total length of females and typical egg mass to understand the relationship between these factors (R version 2.11.0; R Development Core Team 2010).

109

The sex ratio of Mohave tui chub populations represented approximately 1 female: 2 males except for Lake Tuendae where the sex ratio was 2 females: 1 male. Sexually mature males possessed small, light-colored tubercles mainly on head, dorsum and pectoral fins (Figure

A.4). In addition, some large males (approximately > 200 mm) possessed tubercles all over the body including pelvic and anal fins. A distinct hump was developed in sexually mature males, separating the head from the rest of the body. Rarely, I observed very large females

(approximately > 200 mm) with faint tubercles on the head. Therefore tubercle production may suggest the individual is a male, unless the fish is very large.

Figure A.4. Tubercle formation on an adult male Mohave tui chub (Siphateles bicolor mohavensis) from Lake Tuendae. Also note the dorsal hump (Photo: Sujan Henkanaththegedara).

110

2 The average GSI did not vary significantly across habitats (X 3 = 5.5759; p = 0.1342;

Figure A.5). The fecundity of female tui chubs exponentially increased (y = 27.5e0.0437x; R² =

0.68) with the total length (Figure A.6-A) and exponentially decreased (y = 11325e-2716x; R² =

0.65) with typical egg mass (Figure A.6-B). The lowest average fecundity was reported from MC

Spring (1161 ± 748), while the highest average fecundity was reported from Lake Tuendae (8200

± 1064). However, the largest eggs were produced by MC Spring fish and the smallest by Lake

Tuendae fish (Figure A.6-B). The fecundity of fish sampled by Vicker (1973) from Lake

Tuendae ranged from 3393 – 8964 with an average of 5255. In addition, he reported a larger female tui chub (standard length: 215 mm) with an estimated fecundity of about 50,000 eggs

(Vicker 1973).

Figure A.5. Variations of Gonado-somatic Index (GSI) of Mohave tui chubs (Siphateles bicolor mohavensis) across sex and habitats. Error bars represent ± 1 SE Numbers above bars represent the sample size for each category.

111

Figure A.6. Correlations of fecundity with body size (A) and typical egg mass (B) of female Mohave tui chub (Siphateles bicolor mohavensis). Different symbols represent different populations of tui chub.

112

Fish Diet

The same tui chub specimens dissected for age structures were used for diet analysis

(Table A.1). Additionally, at Lake Tuendae western mosquitofish (Gambusia affinis) and tui chubs were collected at the same time allowing me to evaluate diet overlap. Gut contents from the first 1/3 of the gut was removed, sorted, identified to the lowest possible taxa using standard keys and counted (Numerical Method; Windell 1968). Mohave tui chub diet was described using several standard indices. Percentage occurrence of different food items was described as the percentage of all stomachs containing food in which each food category occurred (Wallace

1981). Percentage composition was estimated as the percentage of each food category contributed to the total number of food items in pool stomachs across all individuals (Wallace

1981).

In addition, the heterogeneity of food items consumed was estimated with Shannon-

Weiner Diversity Index (H’) (Krebs 1999) and the number of equally common species in the diet

(N1) was estimated using H’ (McArther 1965). This measure is recognized as the best heterogeneity measure due to its sensitivity to the abundance of rare species in the community

(Peet 1974). I excluded insect parts and plant matter because they were hard to quantify.

s H'  - p log p  ii 2  i 1

H Ne1 

Where,

Pi = proportion of individuals using resource i e = 2.71828 (base of natural logs)

Evenness of the food items consumed was estimated using Simpson’s index of evenness

113

(E1/D). First it is required to estimate Simpson’s diversity index (D) in order to estimate E1/D.

Dp  2  i

1 Dˆ E 1  D S

Where,

Pi = Proportion of species I in the community s = Number of species in the sample

Food niche overlap between Mohave tui chub and mosquitofish at Lake Tuendae was estimated using 5 different niche overlap indices with 16 resource states assuming equal abundance of all resource states (Krebs 1999). Use of multiple niche overlap indices is recommended, because different indices can result in different values for food niche overlap for the same data set (Wallace 1981). A software program accompanied by Krebs (version 7.1;

1999) was employed for estimates of heterogeneity, evenness and food niche overlap indices.

In general, Mohave tui chubs fed on invertebrates such as cladocerans, copepods, ostracods, chironomid larvae and amphipods. However, only a few recognizable food items were reported from Camp Cady compared to other sites. In addition, I found considerable amounts of unidentifiable insect parts and plant matter in tui chub guts from all four populations. Overall 15 identifiable food items were reported from all tui chub populations excluding unidentifiable insect parts and plant matter. Fourteen food items were reported for Lake Tuendae Mohave tui chubs followed by 8, 7 and 4 food items for tui chubs from MC Spring, China Lake and Camp

Cady respectively. Percentage occurrence of various food items in tui chub guts was different between habitats (Figure A.7). Some invertebrate taxa were represented in all tui chub populations and some were restricted to one or a few populations. For example, cladocerans and

114 chironomid larvae were present in tui chub guts from all four tui chub populations, while copepods and water mites were absent in Camp Cady tui chub guts (Figure A.7). Previous work on Lake Tuendae tui chub diet reported gyrinid larvae, chironomid larvae, and small tui chubs

(Vicker 1973). In addition, tui chub diet studies from China Lake reported cladocerans, chironomids, amphipods, trichopterans, small tui chubs, and filamentous green algae (Feldmeth et al. 1985).

Also there were apparent differences of percentage composition of food items between habitats (Figure A.8). For example, cladocerans represented 92%, 34%, 3% and 1% in China

Lake, MC Spring, Camp Cady and Lake Tuendae respectively. Fish eggs contributed 50% of the food items in Camp Cady, 0.2% in Lake Tuendae and absent in two other populations. It is important to note that guts from Camp Cady tui chubs were 50% full of fish eggs. There are no other fish species in this habitat and this may reflect poor food availability for this dense population (Figure A.8).

Heterogeneity and evenness indices indicated the highest heterogeneity of food items at

MC Spring. This may reflect the fair distribution of various food items in the diet of MC Spring tui chubs compared to dominance of other habitats by one food item. However, it accounts for comparatively higher number of equally common species and higher evenness, probably due to large amounts of cladocerans in the diet. The estimates for Lake Tuendae, Camp Cady and China

Lake indicated a balance between heterogeneity and evenness, and China Lake indicated the least heterogeneity probably due to dominance of cladocerans in tui chub diet. Lake Tuendae and

Camp Cady heterogeneity estimates (H’) indicate intermediate values probably due to dominance of the diet by chironomids and fish eggs respectively (Table A.2).

115

Figure A.7. Percentage occurrence of major food items in Mohave tui chub (Siphateles bicolor mohavensis) guts among four populations.

116

117

Figure A.8. Percentage composition of major food items in Mohave tui chub (Siphateles bicolor mohavensis) guts among four populations.

117

Table A.2. Heterogeneity and evenness of food items of Mohave tui chubs (Siphateles bicolor mohavensis) from four populations. Total N indicates the total number of individual food items in pooled gut samples (24 for MC Spring and 30 each for the rest) excluding unidentifiable insect parts and plant matter. Heterogeneity was measured in terms of Shannon-Weiner index (H’) and number of equally common species (N1) while evenness was measured using Simpson’s measure of evenness (E1/D).

Population Number of Total N Heterogeneity Evenness

food items H' N1 E1/D MC Spring 8 96 2.423 5.36 0.559

Lake Tuendae 14 1578 1.727 3.31 0.184

Camp Cady 4 32 1.434 2.7 0.595

China Lake 7 4183 0.51 1.42 0.168

Five different indices estimated the food niche overlap between Mohave tui chub and western mosquitofish at Lake Tuendae in the range of 0.690 – 0.891. However, four of five indices estimated fairly close values except percent overlap measure (Table A.3). In general,

Morisita's Index has been accepted as the best measure of niche overlap, due to zero bias at all sample sizes and when there are a large number of resources (Smith and Zaret 1982).

Furthermore, food niche overlap over 0.6 (in 0-1 scale) is considered to be biologically significant and can provide circumstances for inter-specific competition for food (Zaret and Rand

1971; Mathur 1977).

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Table A.3. Food niche overlap between Mohave tui chub (Siphateles bicolor mohavensis) and western mosquitofish (Gambusia affinis) at Lake Tuendae.

Food niche overlap index Possible range Niche overlap

Pianka’s measure of overlap (Pianka 1973) 0 – 1 0.891

Percent overlap measure (Renkonen 1938) 0 – 100 68.999

Morisita’s original index of overlap (Morisita 1959) 0 – 1 0.884

Simplified Morisita’s index of overlap (Horn 1966) 0 – 1 0.880

Horn’s index of overlap (Horn 1966) 0 – 1 0.823

Literature Cited

Beamish, R.J. and G.A. McFarlane. 1987. Current trends in age determination methods. Pp 15-

42, In. R.C. Summerfelt and G.E. Hall, editors. Age and growth of fish. Iowa State

University Press, Ames.

Cailliet, G.M., M.S. Love, and A.W. Ebeling. 1986. Fishes: A Field and Laboratory Manual on

Their Structure, Identification and Natural History. Waveland Press, Inc. Long Grove, IL.

Crain, P.K. and D.M. Corcoran. 2000. Age and growth of tui chub in Eagle Lake, California.

California Fish and Game 86(2): 149-155.

Feldmeth, R., D. Soltz, L. McClanahan, J. Jones, and J. Irwin. 1985. Natural resources of the

Lark Seep system (china Lake, CA) with special emphasis on the Mohave chub (Gila

bicolor mohavensis). Proceedings of the Desert Fishes Council XIII-XV-B:356-358.

Heppell, S.S. 1998. Application of Life-History Theory and Population Model Analysis to Turtle

Conservation, Copeia 1998:367-375.

119

Hughson, D. and D. Woo. 2004. Report on a workshop to revisit the Mohave tui chub recovery

plan and a management action plan. National Park Service.

Horn, H.S. 1966. Measurement of “overlap” in comparative ecological studies. American

Naturalist 100:419-424.

Krebs, C. 1998. Ecological Methodology. 2nd edition. Addison-Welsey Educational Publishers,

Inc. California.

MacArther, R.H. 1965. Patterns of species diversity. Biological reviews 40:510-533.

Mathur, D. 1977. Food habits and competitive relationships of the bandfin shiner in Halawakee

Creek, Alabama. The American Midland Naturalist 97: 89-100.

Morisita, M. 1959. Measuring of interspecific association and similarity between communities.

Memoirs of the Faculty of Science of Kyushu University Series E Biology 3: 65-80.

Peet, R.K. 1974. The measurement of species diversity. Annual Review of ecology and

Systematics 5:285-307.

Pianka, E.R. 1973. The structure of lizard communities. Annual Reviews of Ecology and

Systematics 4:53-74.

Quist, M.C., Z.J. Jackson, M.R. Bower and W.A. Hubert. 2007. Precision of hard structures used

to estimate age of riverine catostomids and cyprinids in the upper Colorado River basin.

North American Journal of Fisheries Management. 27: 643-649.

R Development Core Team (2010). R: A language and environment for statistical computing. R

Foundation for Statistical Computing, Vienna, Austria. http://www.R-project.org.

Renkonen, O. 1938. Statisch-okologische Untersuchungen uber die terrestiche kaferwelt der

finnischen bruchmoore. Ann. Zool. Soc. Bot. Fenn. 6:1-231.

120

Reznick DA, Bryga H, Endler JA (1990) Experimentally induced life-history evolution in a

natural population. Nature 346:357–359.

Roff, D.A. 1992. The evolution of life histories: theory and analysis, Chapman and Hall, Inc.

New York.

Scoppettone, G.G. 1988. Growth and longevity of Cui-ui and longevity of other catostomids and

cyprinids in Western North America. Transactions of American Fisheries Society. 117:

301-307.

Smith, E.P. and T.M. Zaret. 1982. Bias in estimating niche overlap. Ecology 63: 1248-1253.

Taylor, T.L. and D. McGriff. 1985. Age and growth of Mohave tui chub Gila bicolor

mohavensis from two ponds at Ft. Soda. Proceedings of the Desert Fishes Council 13-15-

B:299-302.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. U.S. Fish and Wildlife Service, Portland, Oregon.

Vicker, C. E. 1973. Aspects of the life history of the Mohave chub Gila bicolor mohavensis

(Snyder) from Soda Lake, California. Masters Thesis, California State University,

Fullerton.

Wallace, R.K. 1981. An assessment of diet overlap indexes. Transactions of the American

Fisheries Society 110: 72-76.

Windell, J.T. 1968. Food analysis and rate of digestion, In. Ricker, W.E. (editor). Methods for

assessment of fish production in freshwaters. IBP Handbook No. 3. International

Biological Program/ Blackwell Scientific Publications.

Zaret, T.M. and A.S. Rand. 1971. Competition in tropical stream fishes: support for the

competitive exclusion principle. Ecology 52: 336-342.

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APPENDIX B. MONITORING THE CONSERVATION STATUS OF

ENDANGERED MOHAVE TUI CHUB

Background

()The recovery plans for many endangered fishes, including Mohave tui chub (Siphateles bicolor mohavensis; U.S. Fish and Wildlife Service 1984), typically call for long-term population monitoring to provide critical biological data need to assess the effectiveness of management activities (Williams 1981;Minckley and Douglas 1989; Yoccoz et al. 2001;

Campbell et al. 2002). However, in most cases rich data are unavailable, leaving managers to take a “best current data approach” (Johnson 1999), which utilizes existing data and uses the latest techniques to evaluate the efficiency of current management practices. However, management success is best achieved when a proper sampling design which targets specific management questions is used (Noble et al. 2010).

I have developed protocols for monitoring of extant Mohave tui chub populations, in collaboration with California Department of Fish and Game (Steve Parmenter Personal

Communication), in order to understand population dynamics, population structure, and fish condition. These data can be used with existing molecular data (Chen 2006) to identify source populations for future transplants. Here I report the results of monitoring efforts of Mohave tui chub populations for past 5 years (2005-2009). Further, I attempted to place these results in the context of sparse historic information, future recovery goals and adaptive management strategies.

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Methods

Mark-recapture Methods

We estimated the size of breeding populations for Mohave tui chub in Lake Tuendae

(2007-2009), Camp Cady (2007-2009) and the North Channel of China Lake (2008). We used multiple mark-multiple recapture methods, and marked only fish which were larger than 70 mm in total length (TL here after) and fish less than 70 mm in TL were excluded from population estimates allowing us to estimate the “breeding population” of Mohave tui chub. Fish were captured using either one or a combination of three types of traps, baited with bread (Table B.1 and B.2). Permanent trap stations were set along the banks of the habitat, and traps were deployed randomly at one of three distances from the bank (0 m, 10 m or 20 m from the bank) for each sampling session. In Camp Cady, traps were suspended just beneath the water surface using plastic buoyants to avoid possible lethal oxygen levels previously observed in deeper areas.

Such lethal oxygen levels were only an issue at Camp Cady. The type and the number of traps were determined based on the habitat type and the availability of traps (Table B.1).

Traps were deployed approximately 3 hours after which they were recovered. The catch was removed from traps and placed in to an aerated live car. Subsequently fish were anesthetized using 50 mg/L of MS-222 before handling. Every unmarked fish was measured for TL (to the nearest 1 mm) and a subsample of fish up to 10 fish in each 10 mm size classes were measured for wet mass (to the nearest 0.1 g). All fish above 70 mm in TL were marked by clipping a small portion of one pelvic fin. Marked fish were returned to a well aerated live car until all fish were processed. Subsequently, marked fish were returned to the habitat at several random locations to maximize mixing of the population (Schnabel 1938). We repeated recapturing and marking new fish up to 8 times and recorded the numbers of marked fish, and unmarked fish. The time

123 duration between two marking sessions varied from 12-24hrs depending on the habitat, available labor, and number of fish caught in the previous session (Tables B.1 and B.2).

Schumacher-Eschmeyer method (Schumacher and Eschmeyer 1943) was utilized to estimate the population size of Mohave tui chubs at Lake Tuendae, Camp Cady and China Lake.

These populations met the spatially closed population criterion under the assumptions of

Schumacher-Eschmeyer method. Additionally, we assumed that the population was demographically closed (zero births and deaths during the sampling period) and each sample was assumed to represent a random sample (Young and Young 1998). A software program by Krebs

(version 7.1; 1999) was employed for all estimates. We accounted for an unexpected fish mortality event which occurred at Camp Cady in 2007 by adjusting the values accordingly.

Depletion Method

Due to small size of MC Spring (Volume ~20 m3), I employed a depletion method (2007-

2009) to estimate population size, consistent with previous censuses in 2005 and 2006 by

California Department of Fish and Game (Steve Parmenter Personal Communication). Fish were captured using either one or a combination of two types of traps baited with bread (Tables B.1 and B.2). Every unmarked fish was anesthetized using 50 mg/L of MS-222 and measured for TL

(to the nearest 1 mm) and wet mass (to the nearest 0.1 g). Processed fish were held in a 55 x 55 x

155 cm3 live car, suspended in the habitat for up to three days. However, the effort was kept constant by deploying the same type and number of traps between sessions. We used absolute accumulated count of captured fish as the total population size, since regression models based on catch-per-unit-effort and accumulated catch (Leslie regression model; Leslie and Davis 1939) underestimated the population size in most cases (Table B.3).

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Table B.1. Details of the Mohave tui chub sampling (Siphateles bicolor mohavensis): dates, methods, traps used and trapping sessions.

Population Year Dates Method Traps used No. of Inter-session Promar 16.5’ Minnow 24’ “Susan” sessions time interval MC Spring 2007 1/22-24/2007 Depletion 0 25 1 2 ~24 hrs 2008 3/9/08-3/11/08 method 0 25 1 6 ~12 hrs 2009 3/07/09-3/09/09 0 25 1 6 ~12 hrs Lake Tuendae 2007 4/26/07-5/7/07 Mark-recapture 0 7 7 7 ~24 hrs 2008 3/12/08-3/27/08 method 0 0 18 6 ~12 hrs 2009 3/10/09-3/12/09 0 0 16 5 ~12 hrs Camp Cady 2007 5/10/07-5/12/07 Mark-recapture 20 0 0 3 ~24 hrs 2008 3/31/08-4/02/08 method 0 0 10 6 ~12 hrs 2009 4/30/09-5/05/09 0 0 16 5 ~24 hrs China Lake 2008 4/21/08-4/24/08 Mark-recapture 0 0 18 8 ~12 hrs

125 (North Channel) method

Table B.2. Details of the traps used to sample Mohave tui chub (Siphateles bicolor mohavensis).

Trap type Shape Length Mesh Mesh size Number of Entrance (cm) type (mm) entrances diameter (cm) Promar TR-501 Cuboid 45.72 polyethylene netting 1.2 2 6.35

16.5” standard Torpedo shaped 41.91 Steel mesh 6.35 2 2.54-5.08 Minnow 24” custom-made Cylindrical 60.96 Steel mesh 6.35 2 5.08 (“Susan”)

125

Population Density and Structure

The population density of each population was estimated by dividing the estimated population size by the approximate volume of the habitat. Approximate volumes of habitats were estimated with surface dimensions and depth profile data collected using a 10 m x 20 m grid.

North Channel information was provided by California Department of Fish and Game (Steve

Parmenter Personal Communication). For Lake Tuendae, Camp Cady and China Lake, the population density estimates are limited to adult “breeding” population (fish > 70 mm in TL).

For MC Spring, we estimated total population size and density using all fish caught during depletion sampling (above and below 70 mm). In addition, we included the tui chubs temporarily removed from Lake Tuendae for field experiments when estimating the population density for Lake Tuendae (Table B.3).

Fish TL data collected during population were used to analyze length frequency distributions. Length frequency histograms were visually examined for characteristics for a stable population (Neumann and Allen 2010). Young-Adult Ratio, the number of young per adult, was used to compare the relative reproductive success of MC Spring population (Reynolds and Babb 1978). We defined all tui chubs less than 50 mm in TL as young-of-the year (YOY) and all fish above 70 mm in TL as adult (Vicker 1973). Fish between 50 mm and 70 mm in TL were excluded to minimize any discrepancies of the developmental stage.

Fish Condition

Fish condition, an estimate of individual fish health (Blackwell et al. 2000), was assessed using length-weight data collected during population estimates. Fulton’s condition factor (K) was utilized as an index to compare the fish condition of Mohave tui chubs (Pope and Kruse 2010).

This index may provide a relative measurement of fish health (Anderson and Neumann 1996).

126

K = (weight/ length3) x10,000

Assuming isometric growth of tui chubs, K = 1.0 indicates an average health while deviations indicate either poor health (K < 1.0) or good health (K > 1.0; Anderson and Neumann

1996).

Results and Discussion

MC Spring

MC Spring is a small spring-like habitat (volume ~20 m3) located near the shore line of

Soda Dry Lake. Some researchers and managers argue that MC Spring is the presumptive stock for all existing Mohave tui chubs (Hughson and Woo 2004; Chen 2006; Steve Parmenter

Personal Communication). However, the first report of Mohave tui chub in MC Spring was reported by Vicker (1973) and further mentioned that fish was introduced from Lake Tuendae by the tenants of the property.

The depletion sampling method allowed us to census the MC Spring population. Total population size of Mohave tui chubs declined from 618 in 2005 to 255 in 2008, and “recovered” to 495 in 2009 (Table B.3). Length frequency distribution of a fish population reflects interactions of reproduction rate, recruitment, growth and mortality (Neumann and Allen 2010).

In this case, the histograms revealed that the extreme fluctuations of the population size were due to fluctuations of recruitment success. MC Spring population had extremely low recruitment success from 2006-2008. However, fish in 20-40 mm size class were abundant in 2005 and 2009

(Figure B.1). Young-Adult Ratio of the MC Spring population also reflects the limited recruitment from 2006 to 2008 compared to 2005 and 2009 (Figure B.2).

127

The MC Spring supports a relatively high density of fish (6.17 – 14.95 individuals/m3) compared to historic data. In contrast to my sampling, Soltz (1978) trapped only 3 individuals in

August 1977 with 3 minnow traps submerged for 11 hours. The historic highest population of 58 fish (95% confidence intervals: 42-102) was reported in April 1981 from a yearlong mark- recapture study (Taylor 1982).

Table B.3. Estimated total population size of Mohave tui chubs (Siphateles bicolor mohavensis) for MC Spring (Leslie regression model: Leslie and Davis 1939) and breeding population sizes for Lake Tuendae, Camp Cady-Bud’s Pond and China Lake-North Channel (Schumacher- Eschmeyer method; Schumacher and Eschmeyer 1943). The number of Lake Tuendae fish removed from the population for field experiments is shown in the last column.

Population Year Number Estimated Lower Upper Fish in marked/ population 95% 95% Mesocosms captured size C.I. C.I. MC Spring 2005† 618 591.2 537.7 664.4 - 2006† 357 424.1 ** ** - 2007 369 345.5 ** ** - 2008 255 269.8 183.3 1134.5 - 2009 496 482.6 463.8 503.3 - Lake Tuendae 2007 1049 1233.7 1119.8 1373.5 200 2008 2568 3201 2887.3 3591.2 160 2009 2741 4277.9 3581.6 5310.3 160 Camp Cady 2007 1488 3409.7 2813.7 4326.1 - 2008 3897 5095.3 4813.5 5412.2 - 2009 4273 5782.4 5420.7 6195.7 - China Lake 2008 504 1687.9 1055.4 4213.1 - (North Channel)

** Sample size is too small to calculate the confidence intervals. † MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game.

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Table B.4. TL (mm) of Mohave tui chub (Siphateles bicolor mohavensis) sampled across 4 habitats and 5 years. Sample size depicts total population size for MC Spring and number of fish handled during mark-recapture sessions for other habitats.

Population Year Sample size Mean (+/-SE) Median Range MC Spring 2005† 618 52.45 (+/-0.74) 48 20 - 170 2006† 356 56.76 (+/-0.70) 53 38 - 156 2007 369 62.61 (+/-0.75) 59 29 - 175 2008 255 70.34 (+/-0.62) 69 47 - 148 2009 495 57.84 (+/-0.68) 53 40 - 156 Lake Tuendae 2007 821 110.43 (+/-0.96) 104 53 - 292 2008 3033 101.05 (+/-0.46) 96 46 - 272 2009 3651 88.78 (+/-0.34) 83 55 - 309 Camp Cady 2007 1099 106.37 (+/-0.34) 106 61 - 202 2008 4515 93.89 (+/-0.24) 95 95 - 161 2009 4589 95.23 (+/-0.20) 95 57 - 230 China Lake 2008 755 139.07 (+/-1.83) 138 44 - 258 (North Channel)

† MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game.

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Figure B.1. Percentage length frequency distribution of MC Spring Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2005-2009. Arrows indicate 2005 YOY cohort. MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game.

130

4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 Young Adult Ratio Adult Young 0.0 2005 2006 2007 2008 2009 Year

Figure B.2. Fluctuations of Young-Adult Ratio (YAR) of Mohave tui chub (Siphateles bicolor mohavensis) at MC Spring from 2005-2009. MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game.

Table B.5. Population density of Mohave tui chub (Siphateles bicolor mohavensis) for MC Spring, Lake Tuendae, Camp Cady-Bud’s Pond, and China Lake-North Channel. Density and confidence intervals C.I. were estimated by dividing the total/estimated population size by the approximate volume of the habitat.

Population Year Estimated Lower 95% C.I. Upper 95% C.I. population density (individuals/m3) (individuals/m3) (individuals/m3) MC Spring 2005† 14.95 - - 2006† 8.64 - - 2007 8.93 - - 2008 6.17 - - 2009 12.00 - - Lake Tuendae 2007 0.24 0.22 0.26 2008 0.56 0.51 0.62 2009 0.74 0.62 0.91 Camp Cady 2007 1.43 1.18 1.81 2008 2.14 2.02 2.27 2009 2.43 2.27 2.60 China Lake 2008 0.88 0.55 2.19 (North Channel)

† MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game. 131

Fish condition was negatively correlated with MC Spring population density. The lowest average Fulton’s condition factor was recorded for 2006 fish (0.896 ± 0.007) indicating “poor” fish condition. However, with decreasing population size, it increased to 1.013 (± 0.007) in 2008 suggesting “average” condition and dropped back to 0.915 (± 0.009) with increased population in 2009 (Table B.6).

Table B.6. Fulton’s condition factor (C) of Mohave tui chub (Siphateles bicolor mohavensis) sampled across 4 habitats and 4 years. MC Spring values are based on the data collected from the total population while values for other populations are based on the data collected for “breeding” population (fish > 70 mm TL).

Population Year Sample size Mean (+/-SE) Median Range

MC Spring 2006† 355 0.896 (+/-0.007) 0.886 0.359-1.469 2007 369 0.922 (+/-0.006) 0.911 0.540-1.429 2008 255 1.013 (+/-0.007) 1.004 0.669-1.391 2009 495 0.915 (+/-0.009) 0.904 0.235-2.113 Lake Tuendae 2007 151 1.183 (+/-0.008) 1.176 0.922-1.634 2008 172 1.107 (+/-0.013) 1.139 0.482-1.565 2009 142 1.186 (+/-0.013) 1.160 0.810-2.101 Camp Cady 2007 92 0.949 (+/-0.011) 0.941 0.718-1.282 2008 114 1.091 (+/-0.013) 1.139 0.482-1.565 2009 94 1.186 (+/-0.013) 1.160 0.714-1.762 China Lake 2008 192 1.240 (+/-0.017) 1.220 0.797-2.890 (North Channel)

† MC Spring 2005 and 2006 data courtesy of Steve Parmenter, California Department of Fish and Game.

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MC Spring population recovery in 2009 after a steady decline since 2005 may be due to several management actions conducted in collaboration with California Department of Fish and

Game. From 2007 to 2009, managers removed the largest individuals from the population in order to reduce variance in reproductive success and any cannibalistic impacts. Additionally, more than 8 large individuals of predaceous diving beetles (family Dytiscidae) were removed from the MC Spring during the 2008 population census. Artificial cover material was also deployed along the periphery of the habitat in April 2008 (Figure B.3) to provide cover for developing larvae. These management actions appear to have reduced predation pressure and increased larval survival by providing protective cover during the early developmental stages

(Figure B.1).

(A) (B)

Figure B.3. Artificial cover suspended along the periphery of MC Spring (A) may have helped the survival of developing Mohave tui chub (Siphateles bicolor mohavensis) larvae and subsequent recruitment (B). Arrows indicate developing chub larvae (Photos: Sujan Henkanaththegedara).

133

Lake Tuendae

Historic reports (Thompson 1929; Miller 1938) discuss a large spring-fed pool located at the approximate location of present-day Lake Tuendae. Furthermore, some early works on the fish in Lake Tuendae describe the occurrence of “minnows” in the original spring-fed pool in as early as 1907 (Miller 1938) and enlargement of the original spring pool to create Lake Tuendae in early 1940s (Vicker 1973; Turner and Liu 1976). Lake Tuendae tui chubs have been used as the source population for new refuge populations since early 1950s (Miller 1968; Hoover and

St.Amant 1983).

The estimated population of “breeding” tui chubs (fish > 70 mm in TL) at Lake Tuendae varied from 1434 fish in 2007 to 4438 fish in 2009 (Table B.3). The initial low population size may reflect the natural variation of the population size. However, these values are well within the previous population estimates for this population. The earliest estimate of 5500-6000 total population size in March-October in 1973 was an estimate based on visual observations and collections (Vicker 1973). Soltz (1978) reported a “breeding” population size of 2744 fish in July

1977. A yearlong study conducted by Taylor (1982) reported a lowest total population size of

1450 fish in February 1982 and a highest of 5678 fish in August 1981, providing clues for seasonal fluctuations of population size. Garron (2006) reported an April breeding population size of 2241 and 3354 in 2004 and 2005, respectively (Table B.7 for more details).

Length frequency histograms suggested a consistent recruitment for tui chubs in Lake

Tuendae (Figure B.4). The average fish size in 2007 (TL = 110.43 ± 0.96 mm) dropped with increasing population size in 2009 (88.78 ± 0.34 mm) (Table B.4). Fulton’s condition factor for

Lake Tuendae stood above 1.1 for the entire sampling period of this study, indicating “good” fish condition (Table B.6). Overall this information on Lake Tuendae tui chub population suggests a

134 relatively robust population despite of the occurrence of invasive western mosquitofish

(Gambusia affinis). Recent population genetic work also confirmed Lake Tuendae population to have relatively higher genetic variability (Chen 2006).

Camp Cady

Historically there were two man-made earthen ponds (east and west) at Camp Cady which supported two Mohave tui chub populations. The west pond (also called Bud’s Pond) tui chub population was established by transplanting 10 and 55 fish from Lake Tuendae in 1986 and

1987, respectively. The east pond was established by transplanting 59 fish from Lake Tuendae in

1987 and augmented by introducing nearly 5000 young-of-the year fish from west pond in 1988.

However, east pond tui chubs were temporary transferred to “fire” pond, leaving only one surviving Mohave tui chub population in Camp Cady. Eventually, 1769 Mohave tui chubs

(originally from east pond) were introduced to west pond in 1992 (Steve Parmenter Personal

Communication). Recently in 2008, nearly 600 captively propagated Mohave tui chubs were introduced to west pond (Steve Parmenter Personal Communication).

This is the first study to report information on population size and structure of Camp

Cady Mohave tui chub population. Camp Cady breeding tui chub population ranged from 3410 fish in 2007 to 5782 fish in 2009. This indicates a net increase of the breeding population towards 2009 (Table B.3). Recruitment of this population may not consistent due to lack of smaller size classes and unimodal nature of the length-frequency histogram for 2007 and unusual peaks in 2008 histogram (Figure B.5). These shifts may reflect inconsistent recruitment and introduction of about 600 captively bred tui chubs in 2008 by California Department of Fish and

Game. These fish were derived from a captive population and were temporally housed in “fire” pond prior to their introduction to west pond.

135

In general, a stable decline of smaller to larger size classes in length-frequency histograms may suggest a “balanced” population (Anderson and Neumann 1996) with continuous recruitment and stable structure. Any deviations from this general pattern may warrant “unbalanced” nature of a population. Therefore, 2009 length-frequency histogram may suggest a partial recovery of the population status. Parallel to the fluctuations of the population size, the structure of the population also changed with comparatively larger fish in 2007, compared to 2008 and 2009 (Table B.4). In addition, 2009 fish indicated “good” condition compared to 2007 fish and 2008 fish, which indicated “poor” and “average” fish conditions, respectively (Table B.6).

Bud’s Pond (i.e. west pond) population of tui chubs were originally founded with 10 fish in 1986 and 55 fish in 1987 from Lake Tuendae. This low number of founders may have posed a severe genetic bottleneck effect in this population (Meffe 1986; Allendorf 1986). In fact, Chen

(2006) showed low genetic diversity of this population compared to Lake Tuendae and China

Lake. The lower genetic diversity combined with “unstable” demographics of this tui chub population makes this population less suitable as a source population for future recovery efforts.

136

Table B.7. A comparison of population estimates of Mohave tui chub (Siphateles bicolor mohavensis) conducted at Lake Tuendae.

Time Method Representative Population lower upper Reference population size 95% CI 95% CI Mar-Oct-73 Visual estimate Total population 5500-6000 - - Vicker 1973 Jul-77a Mark recapture Fish larger than 60 mm SL 2744 2135 3525 Soltz 1978 Jul-77b (Peterson method) 1538 1091 2257 Apr-81 Mark recapture Fish larger than 38 mm SL 2782 1862 5093 Taylor 1982 Jun-81 (Schnabel method) 4130 3424 5203 Aug-81 5678 4303 8327 Oct-81 5588 4314 7929

Dec-81

137

2 2 2 2 2

2 2272 1855 2931

7 7 7 7 7 7

Feb-82 1450 1251 1725

Apr-04 Mark recapture Fish larger than 70 mm TL 2241 2090 2416 Garron 2006 Oct-04 (Schnabel method) 3708 3539 3894 Apr-05 3354 3213 3509 Apr-07 Mark recapture Fish larger than 70 mm TL 1234 1120 1374 This study Mar-08 (Schnabel method) 3201 2887 3591 Mar-09 4278 3582 5310

a- Fish were trapped using umbrella net and minnow traps. b- Fish were trapped using only umbrella net.

137

6 2007 5 4

1 0 6 5 2008 4

3 2 1

8 Percentage frequency Percentage 7 2009 6 5 4 3

2 1

50 60 70 80 90

110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 100

Total length (mm)

Figure B.4. Percentage length frequency distribution of Lake Tuendae Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2007-2009.

138

2007

2008

Percentage frequency Percentage 2009

Total length (mm)

Figure B.5. Percentage length frequency distribution of Camp Cady Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2007-2009.

139

China Lake

China Lake Mohave tui chub population was established by transplanting 400 and 75

Mohave tui chubs from Lake Tuendae to Lark Seep in 1971 and 1976, respectively (Hoover and

St. Amant 1983). Subsequently, Mohave tui chubs have colonized extensive channel and seep system (Feldmeth et al. 1985), making China Lake, the largest extant refuge population of

Mohave tui chub (Susan Williams and Anna-Marie Easley Personal Communications).

Currently, tui chubs occupy four major areas within China Lake seep system: 1) G1 Channel, 2)

North Channel, 3) George Channel and 4) Lark Seep (Susan Williams Personal Communication).

At China Lake, I was able to sample only the North Channel habitat in 2008 due to security reasons. The breeding tui chub population size for North Channel was 1688 in 2008

(Table B.3) with relatively higher average Fulton’s condition factor (1.240 ± 0.017). Length- frequency histogram for 2008 indicated healthy recruitment as well as a considerable number of large individuals indicating a “healthy” population (Figure B.6). A mark-recapture survey for this sub-population conducted in October 2002 estimated 1400 fish (95% confidence intervals:

817 – 1983; Susan Williams Personal Communications). Our results for population size may suggest a growth of the population since 2002. However, the average fish size remains more or less the same (TL of 139.07 mm in 2008 vs. 140.97 mm in 2002). Despite the limited information from our study combined with recent population genetic works (Chen 2006), it appears that this population is sufficiently “healthy” to consider as a source of future translocations. In fact, California Department of Fish and Game recently established a new

Mohave tui chub population at Deppe Pond, Victorville by transplanting 400 young-of-the-year tui chubs from China Lake (Steve Parmenter Personal Communication).

140

Figure B.6. Percentage length frequency distribution of China Lake-North Channel Mohave tui chub (Siphateles bicolor mohavensis) population sampled during 2008.

Management Implications

This study is the first comparative assessment on population dynamics, structure and fish condition of all established Mohave tui chub populations. These results may allow comparison of some aspects of demographic and biological properties of refuge populations of endangered

Mohave tui chub while providing an opportunity to assess the past management efforts.

Collectively our results suggest that Lake Tuendae and North Channel segment of China Lake population are comparatively more robust in terms of population size, population structure, and fish condition. However, the temporal stability of the North Channel population is inconclusive due to lack of data. MC Spring population appears “unstable” at the moment in terms of extreme population density compared to historic data, wide range of population fluctuations, and “poor” fish condition, possibly due to density dependent effects (Smith 1981; Dunham and Vinyard

1997). Furthermore, MC Spring stability may highly depends on keen conservation management practices.

141

The population structure of Bud’s Pond (i.e. west pond) population at Camp Cady appears to be “unstable”, possibly due to inconsistent recruitment and some evidence for density dependent effects. Based on this study and recent population genetic work (Chen 2006), it is advisable to employ Lake Tuendae and China Lake as source populations for future transplants.

Camp Cady should be avoided regardless of the fish abundance and ease of capture due to “poor health” of the population and limited genetic variability.

This study showed the importance of collecting baseline population information for this protected fish species. These data are also useful for assessing management actions such as the intensive management of MC Spring. More importantly this study enhances the knowledge base of demography, biology and population dynamics of endangered Mohave tui chub, and in turn these data can be useful for making informed management decisions in conservation management of this endangered desert fish. These data also produced some insights for the biology and management of other fish occupying small habitats.

Literature Cited

Allendorf, F.W. 1986. Genetic drift and the loss of alleles versus heterozygosity, Zoo Biology 5:

181–190.

Anderson, R.O. and R.M. Neumann. 1996. Length, Weight, and Associated Structural Indices.

Pp. 447-482. In. Murphy, B.R. and D.W. Willis (editors), Fisheries Techniques (2nd

Edition). American Fisheries Society, Bethesda, Maryland.

Blackwell, B.G., M.L. Brown, and D.W. Willis. 2000. Relative weight (Wr) status and current

use in fisheries assessment and management. Reviews in Fisheries Science 8:1-44.

142

Campbell, S.P., J.A. Clark, L.H. Crampton, A.D. Guerry, L.T. Hatch, P.R. Hosseini, J.H. Lawler,

and R.J. O’Connor. 2002. An assessment of monitoring efforts in endangered species

recovery plans. Ecological Applications 12:674-681.

Chen, Y. 2006. Population structure, Introgression, Taxonomy, and Conservation of Endangered

Tui Chubs. Ph.D. Dissertation, University of California Davis.

Dunham, J. B. and G. L. Vinyard. 1997. Relationships between body mass, population density,

and the self-thinning rule in stream-living salmonids. Canadian Journal of Fisheries and

Aquatic Sciences 54:1025-1030.

Feldmeth, R., D. Soltz, L. McClanahan, J. Jones and J. Irwin. 1985. Natural resources of the

Lark Seep system (China Lake, CA) with special emphasis on the Mohave tui chub (Gila

bicolor mohavensis). Proceedings of Desert Fishes Council XIII-XV-B: 356-358.

Garron, K.A. 2006. Population status of the endangered Mohave tui chub (Siphateles bicolor

mohavensis) at Lake Tuendae, Zzyzx, California. Masters Thesis, California State

University, Fullerton.

Hoover, F. and J. A. St. Amant. 1983. Results of Mohave chub, Gila bicolor mohavensis, relocations in California and Nevada. Cal. Fish and Game 69:54-56.

Hughson, D. and D. Woo. 2004. Report on a workshop to revisit the Mohave tui chub recovery

plan and a management action plan. National Park Service.

Johnson, B. L. 1999. The role of adaptive management as an operational approach for resource management agencies. Conservation Ecology 3:10 http://www.consecol.org/vol3/iss1/art10/

Krebs, C.E. 1999. Ecological Methodology. 2nd edition. Addison Wesley Longmann, Inc., Melno

Park, California.

143

Leslie, P.H. and D.H.S. Davis. 1939. An attempt to determine the absolute number of rats on a

given area. Journal of Animal Ecology 8:94-113.

Meffe, G.K. 1986 Conservation Genetics and the Management of Endangered Fishes, Fisheries,

11:14-23.

Miller, R.R. 1938. Description of an isolated population of the freshwater minnow Siphateles

mohavensis from the Mohave River basin, California. Pomona College Journal of

Entomology and Zoology 30:65-67.

Miller, R.R. 1968. Records of some native freshwater fishes transplanted in to various waters of

California, Baja California and Nevada. Calif. Fish and Game. 54:170-179.

Minckley, W.L. and M.E. Douglas. 1989. Discovery and extinction of western fishes: A blink of the eye in geological time. In. pp. 7-17. Minckley, W.L. and J.E. Deacon (editors). Battle Against Extinction: Native Fish Management in the American West. The University of Arizona Press.

Neumann, R.M. and M.S. Allen. 2010. Size structure. Pp. 375-421. In. Guy, C.S. and M.L.

Brown (editors) Analysis and Interpretation of Freshwater Fisheries Data. American

Fisheries Society, Maryland.

Noble, R.L., D.A. Austen, and M.A. Pegg. 2010. Fisheries management study design

considerations. Pp. 31-49. In. Guy, C.S. and M.L. Brown (editors) Analysis and

Interpretation of Freshwater Fisheries Data. American Fisheries Society, Maryland.

Pope, K.L. and C.G. Kruse. 2010. Condition. Pp. 423-471. In. Guy, C.S. and M.L. Brown

(editors) Analysis and Interpretation of Freshwater Fisheries Data. American Fisheries

Society, Maryland.

144

Reynolds, J.B. and L.R. Babb. 1978. Structure and dynamics of largemouth bass populations. Pp.

50-61. In. G.D. Novinger and J.D. Dillard (editors). New approaches to the management

of small impoundments. American Fisheries Society, North Central Division, Special

publication 5, Bethesda, Maryland.

Schnabel, Z.E. 1938. The estimation of the total fish population of a lake. American

Mathematician Monthly 45:348-352.

Schumacher, F.X. and R.W. Eschmeyer. 1943. The estimation of fish populations in lakes and

ponds. Journal of the Tennessee Academy of Sciences 18:228-249.

Smith, G.R. 1981. Effects of habitat size on species richness and adult body size of desert fishes.

In. pp. 125-171. Naiman, R.J. and D.L. Soltz (editors). Fishes in North American Deserts.

A Wiley-Interscience Publication.

Soltz, D.L. 1978. Mohave chub (Gila mohavensis) at Fort Soda, California: Habitat Management

Plan. A report prepared for the Bureau of Land Management; contract # CA-060-CT7-

1797.

Taylor, T. L. 1982. Population size and age and growth of Mohave tui chub at Fort Soda,

California. Draft final report to the Bureau of Land management in fulfillment letter

contract # CA-930-CTI-4.

Thompson, D.G. 1929. The Mohave Desert region, California. Water-supply paper 578.

Geological Survey, U.S. Department of the Interior.

Turner, B.J. and R. K. Liu. 1976. The specific identity of the introduced pupfish at Zzyzx Spring,

California. Copeia 1976:211-212.

U.S. Fish and Wildlife Service. 1984. Recovery plan for the Mohave tui chub, Gila bicolor

mohavensis. U.S. Fish and Wildlife Service, Portland, Oregon.

145

Vicker, C. E. 1973. Aspects of the life history of the Mohave chub Gila bicolor mohavensis

(Snyder) from Soda Lake, California. Masters Thesis, California State University,

Fullerton.

Williams, J.D. 1981. Threatened desert fishes and the endangered species act. In. pp. 447-475.

Naiman, R.J. and D.L. Soltz (editors). Fishes in North American Deserts. A Wiley-

Interscience Publication.

Yoccoz, N.G., J.D. Nichols, and T. Boulinier. 2001. Monitoring of biological diversity in space

and time. Trends in Ecology and Evolution 16:446-453.

Young, L.J. and J.H. Young. 1998. Statistical Ecology: A Population Perspective. Kluwer

Academic Publishers.

146

Table C.1. MC Spring water quality data for 2007.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) H Surface 1/25/07 17.9 1.9 1.6 3119 0.01 8.11 100 100 H Bottom 1/24/07 17.9 1.77 1.6 3123 0.01

H Surface 2/5/07 20.1 4.91 1.6 3100 0.01 8.58 100 100 APPENDIXC. WATER QU H Bottom 2/5/07 19.8 2.65 1.6 3092 1.25 H Surface 2/23/07 20.3 4.95 1.6 3116 0.55 8.56 100 100 H Bottom 2/23/07 20 0.61 1.6 3117 0.01 H Surface 3/8/07 21 2.97 1.6 3121 0.01 8.26 102 102 H Bottom 3/8/07 20.8 0.75 1.6 3127 0.01

1 H Surface 3/22/07 20.2 3.74 1.6 3125 0.01 8.06 100 100 47

H Bottom 3/22/07 20.6 1.21 1.6 3125 0.01 H Surface 4/6/07 22.2 2.66 1.6 3122 0.01 8.12 100 100 H Bottom 4/6/07 22.2 0.34 1.6 3125 0.01 H Surface 4/19/07 20.7 3.04 1.6 3094 0.01 8.3 100 100

H Bottom 4/19/07 20.9 0.19 1.6 3042 0.01 ALITYDATA H Surface 5/3/07 21.5 4.2 1.7 3158 0.01 8.52 100 100 H Bottom 5/3/07 22.2 3.95 1.6 3134 0.01 I Surface 1/25/07 17.9 2 1.6 3112 0.01 8.16 103 103 I Bottom 1/24/07 18.1 0.95 1.6 3105 0.01 I Surface 2/5/07 20.7 5.5 1.6 3098 0.01 8.5 105 105

I Bottom 2/5/07 19.7 0.7 1.6 3113 0.23 I Surface 2/23/07 20.8 5.8 1.6 3101 0.01 8.24 102 102 I Bottom 2/23/07 20.3 0.65 1.6 3128 0.01 I Surface 3/8/07 21.3 3.18 1.6 3106 0.01 8.25 100 100 I Bottom 3/8/07 20.7 0.98 1.6 3120 0.01 a Dissolved oxygen content

Table C.1. (Continued.)

I Surface 3/22/07 20.4 4.26 1.6 3115 0.01 8.02 101 101 I Bottom 3/22/07 20.6 0.86 1.6 3050 0.01 I Surface 4/6/07 22.3 2.52 1.6 3126 0.01 8.05 102 102 I Bottom 4/6/07 22.4 1.11 1.6 3095 0.01 I Surface 4/19/07 20.6 3.7 1.6 3110 0.01 8.3 100 100 I Bottom 4/19/07 20.4 0.59 1.6 3091 0.16 I Surface 5/3/07 22.2 3.65 1.6 3133 1.2 8.45 100 100 I Bottom 5/3/07 22.3 3.94 1.6 3148 0.01 J Surface 1/25/07 17.9 3.22 1.6 3126 0.01 8.13 108 108 J Bottom 1/24/07 17.9 0.39 1.6 3108 0.39 J Surface 2/5/07 20.5 6.13 1.5 2874 0.01 8.51 102 102 J Bottom 2/5/07 19.7 0.82 1.6 3103 1.16

J Surface 2/23/07 20.6 4.7 1.6 3132 0.01 8.55 101 101 1

48 J Bottom 2/23/07 20.2 0.39 1.6 3124 1.74

J Surface 3/8/07 20.9 2.87 1.6 3054 0.12 8.39 108 108 J Bottom 3/8/07 21.2 0.97 1.6 3065 0.01 J Surface 3/22/07 20.5 3.49 1.6 3125 0.01 8.08 102 102 J Bottom 3/22/07 20.2 0.95 1.6 3129 0.01 J Surface 4/6/07 22.2 2.46 1.6 3129 0.01 8.03 107 107 J Bottom 4/6/07 22.1 0.87 1.6 3130 0.01 J Surface 4/19/07 20.3 2.7 1.6 3124 0.3 8.26 105 105 J Bottom 4/19/07 20.1 0.91 1.6 3096 0.01 J Surface 5/3/07 22.1 4.28 1.6 3137 0.49 8.56 104 104 J Bottom 5/3/07 22.1 3.31 1.6 3138 0.01 K Surface 1/25/07 17.8 2.2 1.6 3124 0.01 8.12 105 105 K Bottom 1/24/07 17.5 1.58 1.6 3113 0.01

Table C.1. (Continued.)

K Surface 2/5/07 20.5 5.87 1.6 3099 0.01 8.58 109 109 K Bottom 2/5/07 19.7 0.78 1.6 3118 0.01 K Surface 2/23/07 20.2 5.19 1.6 3121 0.01 8.63 105 105 K Bottom 2/23/07 19.9 1.2 1.6 3108 0.01 K Surface 3/8/07 21 2.98 1.6 3120 0.01 8.2 104 104 K Bottom 3/8/07 20.7 0.41 1.6 3118 0.01 K Surface 3/22/07 20.3 4.22 1.6 3116 0.01 8.08 106 106 K Bottom 3/22/07 20.5 1.31 1.6 3106 0.01 K Surface 4/6/07 22.3 2.52 1.6 3124 0.01 8.03 102 102 K Bottom 4/6/07 22.1 0.55 1.6 3129 0.01 K Surface 4/19/07 20.3 3.06 1.6 3124 0.01 8.23 103 103 K Bottom 4/19/07 20.4 0.09 1.6 3110 0.01

1 K

49 Surface 5/3/07 22.1 4.23 1.6 3134 0.01 8.46 108 108

K Bottom 5/3/07 22 3.62 1.6 3139 0.28

Table C.2. Lake Tuendae water quality data for 2007.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) 1A Surface 1/25/07 11.5 8.99 2.2 4430 0.01 8.86 70 70 1A Bottom 1/25/07 9.3 5.16 2.1 4015 1.49 2A Surface 1/26/07 8.9 11.73 2.1 4020 0.06 9.03 170 170 2A Bottom 1/26/07 8.6 9.48 2.2 4209 1.60 3A Surface 1/26/07 9.9 11.87 2.2 4043 0.01 8.98 137 137 3A Bottom 1/26/07 9.6 6.38 2.2 4150 0.01 4A Surface 1/25/07 12.4 7.65 2.1 4008 1.62 8.90 43 43 4A Bottom 1/25/07 11.9 4.76 2.1 4090 2.24 1B Surface 1/25/07 11.3 9.16 2.1 4021 0.01 8.87 51 51 1B Bottom 1/25/07 10.5 3.44 2.2 4143 2.03

1 2B Surface 1/26/07

50 8.8 11.26 2.1 4025 0.01 9.05 174 174

2B Bottom 1/26/07 8.8 5.78 2.2 4198 0.01 3B Surface 1/26/07 9.9 11.26 2.1 4026 0.01 9.00 135 135 3B Bottom 1/26/07 9.7 5.52 2.2 4218 0.01 4B Surface 1/25/07 12.1 7.81 2.1 3994 0.08 8.96 32 32 4B Bottom 1/25/07 11.7 5.57 2.2 4056 0.47 1C Surface 1/25/07 10.8 6.56 2.1 4012 0.01 8.82 52 52 1C Bottom 1/25/07 10.1 2.66 2.2 4101 0.01 2C Surface 1/26/07 9.0 10.86 2.1 4022 0.01 9.04 130 130 2C Bottom 1/26/07 9.1 0.66 2.2 4193 0.01 3C Surface 1/26/07 10.2 11.37 2.2 4028 0.01 9.14 127 127 3C Bottom 1/26/07 9.6 6.59 2.2 4089 0.01 4C Surface 1/25/07 11.5 8.93 2.2 4053 0.37 9.02 40 40 4C Bottom 1/25/07 11.8 6.63 2.1 4057 0.01 a Dissolved oxygen content

Table C.2. (Continued.)

1D Surface 1/25/07 11.4 6.51 2.1 3881 0.01 8.84 78 78 1D Bottom 1/25/07 9.1 7.42 2.3 4229 2.59 2D Surface 1/26/07 9.2 11.59 2.1 4060 0.01 9.11 48 48 2D Bottom 1/26/07 9.3 7.87 2.1 4058 0.23 3D Surface 1/26/07 9.5 11.45 2.1 4004 0.01 8.97 55 55 3D Bottom 1/26/07 9.6 13.60 2.2 4079 0.01 4D Surface 1/25/07 12.0 10.20 2.1 4005 0.01 9.00 34 34 4D Bottom 1/25/07 11.9 2.93 2.2 4044 0.01 1E Surface 1/25/07 11.7 7.90 2.1 3870 3.58 8.84 80 80 1E Bottom 1/25/07 8.2 7.70 2.3 4219 6.08 2E Surface 1/26/07 8.5 9.73 2.1 3977 0.01 9.03 177 225 2E Bottom 1/26/07 7.5 8.58 2.3 4268 0.01

3E Surface 1/26/07 9.3 10.89 2.1 4006 0.01 9.00 187 208 1

51 3E Bottom 1/26/07 7.8 3.55 2.3 4263 0.01

4E Surface 1/25/07 11.3 7.73 2.1 3898 0.01 8.92 110 110 4E Bottom 1/25/07 8.3 9.22 2.3 4246 0.01 1F Surface 1/25/07 10.6 7.51 2.1 2806 0.09 8.81 96 96 1F Bottom 1/25/07 8.7 6.39 2.2 4112 1.54 2F Surface 1/26/07 9.1 10.88 2.1 3993 0.01 8.98 174 215 2F Bottom 1/26/07 7.6 9.75 2.3 4253 0.10 3F Surface 1/26/07 9.8 10.68 2.1 4002 0.01 8.91 185 185 3F Bottom 1/26/07 7.8 1.19 2.3 4265 0.01 4F Surface 1/25/07 11.2 7.22 2.1 3871 0.56 8.90 110 110 4F Bottom 1/25/07 8.7 9.58 2.3 4263 0.90 2G Surface 1/26/07 9.2 10.36 2.1 3981 0.01 8.92 160 190 2G Bottom 1/26/07 7.6 2.30 2.3 4247 0.44

Table C.2. (Continued.)

3G Surface 1/26/07 9.4 10.23 2.1 3980 0.50 8.89 172 198 3G Bottom 1/26/07 8.1 11.36 2.2 4220 0.01 1A Surface 2/6/07 9.5 8.22 2.2 4147 0.01 9.13 60 60 1A Bottom 2/6/07 9.6 7.63 2.2 4197 8.71 2A Surface 2/6/07 11.9 12.16 2.2 4200 0.16 9.12 130 160 2A Bottom 2/6/07 10.6 5.74 2.2 4165 0.40 4A Surface 2/6/07 14.1 6.08 2.2 4122 2.00 9.10 25 25 4A Bottom 2/6/07 17.4 9.82 2.1 3953 0.82 1B Surface 2/6/07 9.6 9.64 2.2 4156 1.18 9.18 22 22 1B Bottom 2/6/07 9.6 7.60 2.2 4123 0.07 2B Surface 2/6/07 11.5 12.44 2.2 4186 0.01 9.18 150 150 2B Bottom 2/6/07 10.6 10.30 2.2 4174 0.01 4B Surface 2/6/07

1 14.2 13.44 2.2 4134 3.78 9.14 20 20

52 4B Bottom 2/6/07 12.5 9.89 2.2 4182 6.12

1C Surface 2/6/07 9.8 7.72 2.2 4160 0.07 9.19 19 19 1C Bottom 2/6/07 9.8 6.65 2.2 4151 0.59 2C Surface 2/6/07 12.6 12.67 2.2 4173 0.20 9.16 126 132 2C Bottom 2/6/07 10.8 8.54 2.2 4172 0.10 4C Surface 2/6/07 13.0 8.74 2.2 4139 1.16 9.11 20 20 4C Bottom 2/6/07 12.7 6.75 2.2 4185 1.58 1D Surface 2/6/07 10.0 9.36 2.2 4153 0.01 9.18 22 22 1D Bottom 2/6/07 9.9 8.65 2.2 4148 5.29 2D Surface 2/6/07 13.0 12.61 2.2 4174 0.01 9.16 35 35 2D Bottom 2/6/07 12.2 8.86 2.2 4136 0.01 4D Surface 2/6/07 11.9 8.62 2.2 4122 0.38 9.03 10 10 4D Bottom 2/6/07 11.8 5.76 2.2 4131 0.45

Table C.2. (Continued.)

1E Surface 2/6/07 9.9 7.24 2.2 4160 0.07 9.19 87 87 1E Bottom 2/6/07 9.8 8.64 2.2 4166 49.10 2E Surface 2/6/07 13.6 12.35 2.2 4178 0.01 9.14 125 200 2E Bottom 2/6/07 10.5 9.81 2.2 4192 0.01 4E Surface 2/6/07 11.3 8.70 2.2 4148 0.57 9.70 90 90 4E Bottom 2/6/07 10.1 8.44 2.2 4166 3.31 1F Surface 2/6/07 10.1 8.47 2.2 4165 0.54 9.16 82 82 1F Bottom 2/6/07 9.8 7.42 2.2 4159 2.06 2F Surface 2/6/07 13.1 11.23 2.2 4175 0.30 9.18 123 190 2F Bottom 2/6/07 10.2 9.55 2.2 4171 0.03 4F Surface 2/6/07 10.6 9.90 2.2 4185 0.31 9.15 90 100 4F Bottom 2/6/07 9.9 8.12 2.2 4174 2.94 2G Surface 2/6/07 9.13

1 14.4 11.65 2.2 4183 0.29 130 190

53 2G Bottom 2/6/07 10.5 10.38 2.2 4192 0.04

2A Surface 2/24/07 13.0 8.73 2.2 4117 0.01 9.06 140 140 2A Bottom 2/24/07 12.2 8.08 2.2 4097 0.19 3A Surface 2/24/07 12.7 9.56 2.2 4111 0.01 9.08 130 150 3A Bottom 2/24/07 12.2 9.59 2.2 4109 0.01 1B Surface 2/24/07 14.8 6.82 2.2 4089 0.01 9.08 45 45 1B Bottom 2/24/07 14.2 7.32 2.2 4094 0.17 2B Surface 2/24/07 13.2 9.50 2.2 4108 0.01 9.07 125 170 2B Bottom 2/24/07 12.2 11.33 2.2 4094 0.01 3B Surface 2/24/07 12.7 9.53 2.2 4113 0.01 9.09 131 131 3B Bottom 2/24/07 12.2 14.37 2.2 4086 0.01 4B Surface 2/23/07 16.1 5.03 2.2 4097 0.01 9.21 30 30 4B Bottom 2/23/07 16.0 5.45 2.2 4110 1.22

Table C.2. (Continued.)

1C Surface 2/24/07 14.7 6.06 2.2 4113 0.26 9.09 53 53 1C Bottom 2/24/07 14.7 6.99 2.2 4113 0.01 2C Surface 2/24/07 13.3 9.72 2.2 4107 0.01 9.06 130 130 2C Bottom 2/24/07 12.8 8.06 2.2 4061 0.01 3C Surface 2/24/07 13.1 9.50 2.2 4113 0.01 9.08 110 110 3C Bottom 2/24/07 12.6 13.18 2.2 4098 0.01 4C Surface 2/23/07 15.9 7.43 2.2 4102 0.04 9.28 32 32 4C Bottom 2/23/07 15.7 7.22 2.2 4100 0.06 1D Surface 2/24/07 14.5 7.83 2.2 4112 0.01 9.04 52 52 1D Bottom 2/24/07 13.7 6.12 2.2 4097 0.18 2D Surface 2/24/07 13.8 9.24 2.2 4107 0.01 9.17 108 108 2D Bottom 2/24/07 13.8 10.70 2.2 4069 0.01

3D Surface 2/24/07 13.1 9.45 2.2 4103 0.01 9.13 45 45 1

54 3D Bottom 2/24/07 13.2 6.04 2.2 4102 0.55

4D Surface 2/23/07 15.6 7.01 2.2 4105 0.01 9.47 35 35 4D Bottom 2/23/07 15.5 4.85 2.2 4078 0.01 1E Surface 2/24/07 14.5 6.91 2.2 4103 0.07 9.02 90 109 1E Bottom 2/24/07 13.1 5.77 2.2 4104 4.31 2E Surface 2/24/07 13.8 9.41 2.2 4100 0.01 9.06 160 187 2E Bottom 2/24/07 12.7 7.05 2.2 4111 0.04 3E Surface 2/24/07 13.2 9.24 2.2 4102 0.01 9.05 130 200 3E Bottom 2/24/07 12.6 8.11 2.2 4101 0.05 4E Surface 2/23/07 15.4 7.22 2.2 4102 0.12 9.03 90 178 4E Bottom 2/23/07 14.2 7.21 2.2 4096 2.36 1F Surface 2/24/07 15.3 6.83 2.2 4123 0.33 9.03 106 150 1F Bottom 2/24/07 13.1 6.73 2.2 4124 1.79

Table C.2. (Continued.)

2F Surface 2/24/07 14.0 9.68 2.2 4107 0.01 9.05 130 190 2F Bottom 2/24/07 12.6 10.61 2.2 4107 0.06 3F Surface 2/24/07 13.3 9.16 2.2 4112 0.01 9.01 121 185 3F Bottom 2/24/07 12.7 2.35 2.2 4118 0.01 4F Surface 2/23/07 15.1 6.74 2.2 4116 0.01 9.01 87 87 4F Bottom 2/23/07 13.8 5.55 2.2 4087 0.48 2G Surface 2/24/07 14.3 9.43 2.2 4114 0.72 9.03 135 190 2G Bottom 2/24/07 12.7 7.06 2.2 4115 0.01 3G Surface 2/24/07 13.3 9.79 2.2 4110 0.01 9.04 136 195 3G Bottom 2/24/07 12.6 2.79 2.2 4090 0.02 2A Surface 3/8/07 18.6 9.07 2.2 4160 0.01 8.97 130 160 2A Bottom 3/8/07 16.2 10.56 2.2 4150 0.01

3A Surface 3/8/07 18.7 9.99 2.2 4155 0.01 8.97 110 129 1 55 3A Bottom 3/8/07 16.3 11.50 2.2 4153 0.01

1B Surface 3/8/07 16.8 6.61 2.2 3501 0.01 8.93 42 42 1B Bottom 3/8/07 16.6 7.37 2.2 4051 0.01

2B Surface 3/8/07 18.7 9.09 2.2 4170 0.04 8.96 130 151 2B Bottom 3/8/07 16.4 9.57 2.2 4167 0.01

3B Surface 3/8/07 17.7 10.08 2.2 4160 0.01 8.99 125 138 3B Bottom 3/8/07 16.4 10.94 2.2 4164 1.45

4B Surface 3/8/07 18.6 6.17 2.1 4009 0.01 8.94 25 25 4B Bottom 3/8/07 18.4 4.03 2.2 4107 0.80

1C Surface 3/8/07 17.0 6.67 2.2 4145 0.01 8.92 28 28 1C Bottom 3/8/07 16.8 7.53 2.2 4084 0.01

2C Surface 3/8/07 18.6 9.46 2.2 4155 0.01 9.03 120 130 2C Bottom 3/8/07 17.0 10.32 2.2 4124 0.14

Table C.2. (Continued.)

3C Surface 3/8/07 18.6 10.66 2.2 4189 0.01 9.00 120 120 3C Bottom 3/8/07 16.7 10.47 2.2 4132 0.33

4C Surface 3/8/07 17.5 6.84 2.2 4169 0.01 8.81 26 26 4C Bottom 3/8/07 17.9 8.10 2.2 4135 0.01

1D Surface 3/8/07 16.1 7.29 2.2 4156 0.01 8.35 35 35 1D Bottom 3/8/07 15.7 5.72 2.2 4188 0.01

2D Surface 3/8/07 18.4 9.56 2.2 4154 0.01 8.95 128 132 2D Bottom 3/8/07 16.0 8.73 2.2 4122 0.23

3D Surface 3/8/07 18.8 10.05 2.2 4157 0.01 9.26 40 40 3D Bottom 3/8/07 18.5 8.56 2.2 4120 2.31

4D Surface 3/8/07 17.3 7.81 2.2 4143 0.01 9.09 30 30 4D Bottom 3/8/07 17.4 2.35 2.2 4114 0.01

1E Surface 3/8/07 16.0 8.19 2.2 4152 0.01 8.95 105 105 1 56 1E Bottom 3/8/07 15.9 6.65 2.2 4180 2.16

2E Surface 3/8/07 17.9 9.67 2.2 4161 0.01 8.93 128 190 2E Bottom 3/8/07 15.4 9.39 2.2 4131 0.01

3E Surface 3/8/07 19.3 9.62 2.2 4153 0.01 8.97 130 200 3E Bottom 3/8/07 15.4 9.50 2.2 4145 0.01

4E Surface 3/8/07 17.2 6.01 2.2 4144 0.03 8.96 85 110 4E Bottom 3/8/07 15.9 8.98 2.2 4138 0.01

1F Surface 3/8/07 16.1 8.09 2.2 4148 2.93 8.95 100 100 1F Bottom 3/8/07 16.1 7.58 2.2 4167 1.01

2F Surface 3/8/07 18.9 9.37 2.2 4166 0.01 8.94 120 205 2F Bottom 3/8/07 15.8 4.81 2.2 4128 0.13

3F Surface 3/8/07 19.1 9.55 2.2 4186 0.01 8.96 125 170 3F Bottom 3/8/07 15.6 10.40 2.2 4143 0.06

Table C.2. (Continued.)

4F Surface 3/8/07 17.4 6.12 2.2 4168 0.01 8.94 95 95 4F Bottom 3/8/07 15.4 9.98 2.2 4143 0.01

2G Surface 3/8/07 18.9 9.28 2.2 4167 0.27 9.00 110 192 2G Bottom 3/8/07 15.8 7.81 2.2 4152 1.58

3G Surface 3/8/07 20.0 9.52 2.2 4186 0.26 8.97 100 175 3G Bottom 3/8/07 15.9 1.95 2.2 4162 0.23

2A Surface 3/22/07 19.0 9.53 2.3 4247 0.01 8.94 155 162 2A Bottom 3/22/07 19.0 8.50 2.3 4235 0.01

3A Surface 3/22/07 19.1 9.39 2.3 4242 0.01 8.96 145 145 3A Bottom 3/22/07 19.0 9.77 2.3 0.33

1B Surface 3/22/07 18.3 7.62 2.3 4217 0.27 8.93 39 39 1B Bottom 3/22/07 18.5 6.72 2.2 4212 0.19

2B Surface 3/22/07 19.1 10.02 2.3 4243 0.01 8.96 138 138 1 57 2B Bottom 3/22/07 19.0 3.47 2.3 4222 1.97

3B Surface 3/22/07 19.0 9.88 2.3 4243 0.01 8.96 148 160 3B Bottom 3/22/07 18.9 5.47 2.3 4230 0.01

4B Surface 3/22/07 18.9 13.14 2.3 4224 2.78 8.97 20 20 4B Bottom 3/22/07 18.9 6.50 2.3 4224 0.31

1C Surface 3/22/07 18.6 8.49 2.3 4230 0.27 8.96 37 37 1C Bottom 3/22/07 18.7 6.74 2.2 4196 0.40

2C Surface 3/22/07 19.0 10.68 2.3 4240 0.01 8.96 106 106 2C Bottom 3/22/07 19.3 12.33 2.2 4209 0.96

3C Surface 3/22/07 18.9 9.71 2.3 4234 2.16 8.97 130 130 3C Bottom 3/22/07 18.9 4.45 2.3 4226 0.14

4C Surface 3/22/07 18.1 6.57 2.3 4221 0.12 8.71 26 26 4C Bottom 3/22/07 17.8 1.66 2.3 4230 0.01

Table C.2. (Continued.)

1D Surface 3/22/07 18.7 7.42 2.3 4227 1.16 8.90 51 51 1D Bottom 3/22/07 18.7 7.50 2.3 4230 0.11

2D Surface 3/22/07 19.5 9.36 2.3 4228 0.28 8.94 45 45 2D Bottom 3/22/07 19.7 6.41 2.2 4176 0.35

3D Surface 3/22/07 19.2 9.93 2.3 4230 0.50 8.90 125 125 3D Bottom 3/22/07 19.1 8.29 2.3 4226 0.58

4D Surface 3/22/07 18.9 7.07 2.2 4213 0.42 8.90 28 28 4D Bottom 3/22/07 18.7 9.22 2.3 4230 0.55

1E Surface 3/22/07 18.5 7.75 2.2 4216 0.44 8.85 88 105 1E Bottom 3/22/07 18.4 6.28 2.3 4224 1.17

2E Surface 3/22/07 19.2 9.35 2.3 4232 0.15

2E Bottom 3/22/07 18.9 3.88 2.2 4122 0.49 8.87 120 195

3E Surface 3/22/07 19.0 9.05 2.3 4231 0.33 8.89 122 190 1

58 3E Bottom 3/22/07 18.7 5.53 2.3 4222 1.64

4E Surface 3/22/07 18.6 9.05 2.3 4213 0.14 8.93 90 103 4E Bottom 3/22/07 18.4 8.66 2.3 4215 0.13

1F Surface 3/22/07 18.8 6.93 2.3 4245 0.42 8.84 90 90 1F Bottom 3/22/07 18.6 5.82 2.3 4271 1.32

2F Surface 3/22/07 19.2 8.64 2.3 4225 0.12 8.85 128 180 2F Bottom 3/22/07 18.8 2.62 2.2 4209 0.57

3F Surface 3/22/07 18.9 8.78 2.2 4215 0.33 8.86 120 175 3F Bottom 3/22/07 18.6 3.27 2.3 4216 0.16

4F Surface 3/22/07 18.5 8.06 2.2 4211 0.39 8.87 100 100 4F Bottom 3/22/07 18.3 7.11 2.2 4212 4.68

2G Surface 3/22/07 19.4 7.22 2.3 4232 0.31 8.85 115 185 2G Bottom 3/22/07 19.0 7.19 2.3 4227 0.98

Table C.2. (Continued.)

3G Surface 3/22/07 19.2 8.62 2.2 4206 0.15 8.89 108 188 3G Bottom 3/22/07 18.6 5.12 2.2 4209 0.65

2A Surface 4/6/07 22.0 9.81 2.3 4361 0.89 9.13 88 152 2A Bottom 4/6/07 21.1 0.93 2.3 4353 0.96

3A Surface 4/6/07 22.3 9.32 2.3 4366 0.83 9.11 87 145 3A Bottom 4/6/07 21.1 0.60 2.3 4352 0.93

1B Surface 4/6/07 24.3 1.85 2.3 4391 0.79 9.11 29 29 1B Bottom 4/6/07 24.2 6.71 2.3 4388 0.83

2B Surface 4/6/07 22.3 9.80 2.3 4371 0.67 9.13 90 154 2B Bottom 4/6/07 21.0 3.78 2.3 4331 2.25

3B Surface 4/6/07 22.3 9.23 2.3 4368 1.10 9.18 89 120 3B Bottom 4/6/07 21.3 4.14 2.3 4356 5.95

4B Surface 4/6/07 25.4 6.82 2.3 4370 2.44 8.92 15 15 1 59 4B Bottom 4/6/07 25.0 5.12 2.3 4294 4.26

1C Surface 4/6/07 24.7 5.64 2.3 4368 1.11 9.26 30 30 1C Bottom 4/6/07 24.1 7.65 2.3 4350 3.98

2C Surface 4/6/07 22.7 10.40 2.3 4363 0.70 9.18 90 110 2C Bottom 4/6/07 21.3 0.80 2.3 4280 0.63

3C Surface 4/6/07 22.7 10.46 2.3 4370 0.59 9.20 87 98 3C Bottom 4/6/07 21.6 8.05 2.3 4350 1.11

4C Surface 4/6/07 25.1 1.62 2.3 4395 9.58 8.96 20 20 4C Bottom 4/6/07 24.2 0.71 2.3 4390 4.35

1D Surface 4/6/07 24.6 7.52 2.3 4382 0.96 9.11 35 35 1D Bottom 4/6/07 22.7 8.30 2.3 4356 0.58

2D Surface 4/6/07 21.9 10.20 2.3 4396 0.61 9.14 87 165 2D Bottom 4/6/07 21.3 2.91 2.3 4325 0.71

Table C.2. (Continued.)

3D Surface 4/6/07 22.9 11.47 2.3 4341 1.04 9.16 28 28 3D Bottom 4/6/07 22.6 6.35 2.3 4348 1.87

4D Surface 4/6/07 25.1 7.81 2.3 4260 2.86 9.34 19 19 4D Bottom 4/6/07 24.1 0.54 2.3 4367 3.22

1E Surface 4/6/07 24.9 6.72 2.3 4384 2.80 9.03 70 100 1E Bottom 4/6/07 21.5 2.95 2.3 4356 2.71

2E Surface 4/6/07 22.0 10.04 2.3 4348 0.84 9.11 80 189 2E Bottom 4/6/07 20.8 0.61 2.3 4331 0.88

3E Surface 4/6/07 22.7 9.85 2.3 4356 0.48 8.65 80 185 3E Bottom 4/6/07 20.9 0.32 2.3 4344 0.63

4E Surface 4/6/07 24.6 6.63 2.3 4377 1.79 9.10 76 95 4E Bottom 4/6/07 21.4 8.51 2.3 4333 6.07

1F Surface 4/6/07 23.2 6.38 2.3 4358 1.13 8.65 80 80 1 60 1F Bottom 4/6/07 21.7 6.94 2.3 4347 2.33

2F Surface 4/6/07 22.2 9.07 2.3 4364 1.96 9.10 88 182 2F Bottom 4/6/07 20.8 2.42 2.3 4323 1.17

3F Surface 4/6/07 22.5 10.30 2.3 4362 0.58 8.82 85 165 3F Bottom 4/6/07 21.0 0.44 2.3 4336 1.83

4F Surface 4/6/07 24.8 8.78 2.3 4386 0.79 9.10 65 65 4F Bottom 4/6/07 21.7 8.22 2.3 4326 1.90

2G Surface 4/6/07 22.1 9.18 2.3 4330 1.28 9.04 87 170 2G Bottom 4/6/07 20.7 0.75 2.3 4330 0.80

3G Surface 4/6/07 22.7 10.36 2.3 4360 1.71 8.64 80 157 3G Bottom 4/6/07 21.0 1.63 2.3 4334 1.56

2A Surface 4/19/07 18.1 9.13 2.3 4313 0.80 9.01 95 162 2A Bottom 4/19/07 17.3 0.61 2.3 4269 0.72

Table C.2. (Continued.)

3A Surface 4/19/07 19.2 9.49 0.9 1863 0.89 8.95 82 95 3A Bottom 4/19/07 17.8 3.04 1.0 2022 0.91

1B Surface 4/19/07 20.8 4.83 1.2 2337 1.14 9.26 39 39 1B Bottom 4/19/07 19.0 10.14 1.2 2373 0.93

2B Surface 4/19/07 18.3 9.18 2.3 4310 1.04 9.00 82 165 2B Bottom 4/19/07 17.6 1.43 2.3 4237 0.91

3B Surface 4/19/07 19.0 9.41 0.9 1851 1.44 8.96 82 106 3B Bottom 4/19/07 17.9 3.42 1.1 2067 7.03

4B Surface 4/19/07 22.2 7.95 1.2 2409 1.70 9.35 28 28 4B Bottom 4/19/07 22.2 7.48 1.5 2908 1.05

1C Surface 4/19/07 20.8 9.18 1.2 2379 1.18 9.25 40 40 1C Bottom 4/19/07 19.9 8.74 1.2 2314 0.90

2C Surface 4/19/07 18.3 9.65 2.3 4312 0.94 9.06 85 128

1 6

1 2C Bottom 4/19/07 17.5 8.00 2.3 4305 3.61

3C Surface 4/19/07 19.0 10.74 0.9 1705 0.86 9.23 84 84 3C Bottom 4/19/07 18.5 7.84 1.0 1907 2.96

4C Surface 4/19/07 21.8 7.66 1.3 2436 0.87 9.33 34 34 4C Bottom 4/19/07 21.2 1.41 1.3 2499 1.69

1D Surface 4/19/07 21.1 7.90 1.2 2298 1.46 9.26 52 52 1D Bottom 4/19/07 18.9 7.74 2.0 3818 0.75

2D Surface 4/19/07 18.8 9.55 2.3 4314 1.29 9.06 78 124 2D Bottom 4/19/07 18.3 1.10 2.3 4307 1.21

3D Surface 4/19/07 19.8 11.13 0.9 1704 1.04 9.06 80 95 3D Bottom 4/19/07 19.4 2.11 0.8 1639 0.83

4D Surface 4/19/07 21.8 8.48 1.3 2463 1.32 9.37 31 31 4D Bottom 4/19/07 22.2 8.48 1.3 2431 1.17

Table C.2. (Continued.)

1E Surface 4/19/07 20.5 8.00 1.2 2337 1.23 8.93 75 105 1E Bottom 4/19/07 19.3 7.33 2.1 4036 3.04

2E Surface 4/19/07 18.9 9.50 1.9 3614 1.10 9.00 85 180 2E Bottom 4/19/07 17.8 7.90 1.9 3657 6.12

3E Surface 4/19/07 19.6 10.01 0.9 1707 4.09 8.96 85 190 3E Bottom 4/19/07 17.9 8.21 1.0 2012 1.26

4E Surface 4/19/07 21.8 7.16 2.2 4102 1.10 9.27 80 116 4E Bottom 4/19/07 18.6 9.77 1.3 2429 1.58

1F Surface 4/19/07 20.2 6.02 1.9 3613 0.98 9.27 79 108 1F Bottom 4/19/07 19.1 5.92 2.0 3779 4.69

2F Surface 4/19/07 19.3 9.77 1.9 3639 0.85 9.01 75 197 2F Bottom 4/19/07 17.9 0.50 1.9 3673 1.08

3F Surface 4/19/07 19.4 9.54 0.7 1338 1.49 8.98 85 186 1 62 3F Bottom 4/19/07 18.1 0.33 0.8 1555 10.35

4F Surface 4/19/07 22.0 6.42 1.3 2496 2.31 9.27 72 115 4F Bottom 4/19/07 18.8 6.12 1.3 2517 1.58

2G Surface 4/19/07 19.3 8.84 1.1 2128 1.31 8.96 90 178 2G Bottom 4/19/07 17.9 0.15 1.6 3105 1.76

3G Surface 4/19/07 19.4 9.33 1.5 2853 1.47 8.94 80 156 3G Bottom 4/19/07 17.9 8.78 1.7 3153 1.38

2A Surface 5/3/07 22.2 9.69 2.4 4477 2.80 9.52 57 148 2A Bottom 5/3/07 21.2 11.62 2.4 4466 3.33

3A Surface 5/3/07 22.6 10.24 2.4 4487 2.95 9.43 56 103 3A Bottom 5/3/07 21.4 9.05 2.4 4467 3.76

1B Surface 5/3/07 25.1 6.03 2.4 4496 9.31 9.60 30 30 1B Bottom 5/3/07 23.2 11.85 2.4 4465 2.77

Table C.2. (Continued.)

2B Surface 5/3/07 21.7 10.47 2.4 4478 2.82 9.41 60 158 2B Bottom 5/3/07 21.3 11.54 2.4 4465 2.88

3B Surface 5/3/07 22.6 9.39 2.4 4480 2.97 9.52 58 140 3B Bottom 5/3/07 21.5 10.56 2.4 4464 2.82

4B Surface 5/3/07 26.5 6.04 2.4 4511 3.94 9.48 27 27 4B Bottom 5/3/07 26.2 9.16 2.4 4503 5.55

1C Surface 5/3/07 25.0 7.42 2.4 4526 3.16 9.64 30 30 1C Bottom 5/3/07 24.6 11.73 2.4 4492 3.01

2C Surface 5/3/07 21.7 11.30 2.4 4476 3.04 9.52 58 120 2C Bottom 5/3/07 21.3 12.20 2.4 4468 3.77

3C Surface 5/3/07 22.5 9.89 2.4 4476 2.92 9.54 60 110 3C Bottom 5/3/07 21.7 10.56 2.4 4486 4.75

4C Surface 5/3/07 25.7 9.11 2.4 4503 9.89 9.59 26 26 1 63 4C Bottom 5/3/07 25.9 10.61 2.4 4505 3.61

1D Surface 5/3/07 24.9 7.67 2.4 4487 4.34 9.51 25 25 1D Bottom 5/3/07 24.9 6.80 2.4 4499 4.39

2D Surface 5/3/07 22.5 11.20 2.4 4462 3.30 9.32 53 127 2D Bottom 5/3/07 22.1 10.21 2.3 4390 3.24

3D Surface 5/3/07 23.5 11.36 2.4 4470 2.95 9.53 50 50 3D Bottom 5/3/07 23.6 7.27 2.4 4437 3.31

4D Surface 5/3/07 26.2 8.12 2.4 4506 3.93 9.50 24 24 4D Bottom 5/3/07 26.1 9.76 2.4 4480 3.00

1E Surface 5/3/07 25.0 5.95 2.4 4489 3.09 9.48 45 98 1E Bottom 5/3/07 23.2 6.85 2.4 4480 4.72

2E Surface 5/3/07 22.4 10.42 2.4 4460 3.20 9.32 60 190 2E Bottom 5/3/07 21.7 9.67 2.4 4460 3.71

Table C.2. (Continued.)

3E Surface 5/3/07 23.1 10.09 2.4 4470 3.47 9.36 63 190 3E Bottom 5/3/07 21.8 7.92 2.4 4417 2.91

4E Surface 5/3/07 25.5 6.85 2.4 4499 3.72 9.51 50 90 4E Bottom 5/3/07 23.3 8.46 2.4 4441 7.95

1F Surface 5/3/07 24.1 6.42 2.4 4502 7.81 9.47 50 87 1F Bottom 5/3/07 23.2 7.40 2.4 4448 3.51

2F Surface 5/3/07 22.3 10.12 2.4 4459 3.35 9.49 55 190 2F Bottom 5/3/07 21.6 8.63 2.4 4452 3.32

3F Surface 5/3/07 23.1 9.87 2.4 4463 3.02 9.39 63 165 3F Bottom 5/3/07 21.9 5.71 2.3 4388 3.19

4F Surface 5/3/07 25.5 6.87 2.4 4483 3.47 9.54 55 98 4F Bottom 5/3/07 22.6 11.03 2.4 4461 2.91

2G Surface 5/3/07 22.6 9.67 2.4 4462 3.21 9.36 54 185 1 64 2G Bottom 5/3/07 21.8 7.16 2.4 4453 4.09

3G Surface 5/3/07 23.1 9.69 2.4 4458 2.94 9.37 60 168 3G Bottom 5/3/07 21.9 9.23 2.3 4461 2.96

Table C.3. MC Spring water quality data for 2008.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) H Surface 1/25/08 18.5 6.1 1.6 3002 8.27 105 105 H Bottom 1/25/08 18.6 2.69 1.5 2932 8.27 H Surface 2/20/08 20.2 6.07 1.6 3119 2.76 8.3 100 100 H Bottom 2/20/08 20.1 6.44 1.6 3126 3.3 8.3 H Surface 3/18/08 19.4 4.97 1.6 3125 1.45 8.2 97 97 H Bottom 3/18/08 19.2 5.24 1.6 3130 2.57 8.2 H Surface 4/19/08 23.4 10.96 1.7 3214 0.64 8.5 90 90 H Bottom 4/19/08 23.1 5.28 1.7 3253 2.38 8.6 H Surface 5/10/08 22.9 5.04 1.7 3209 3.09 7.9 89 89 H Bottom 5/10/08 22.7 5.3 1.7 3207 0.58 7.9

165 I Surface 1/25/08 18.5 6.63 1.5 2842 8.29 105 105

I Bottom 1/25/08 19 5.78 1.5 2581 8.29 I Surface 2/20/08 20.2 6.39 1.6 3120 3.21 8.4 96 96 I Bottom 2/20/08 20.1 6.22 1.6 3128 0.97 8.3 I Surface 3/18/08 19.4 5.24 1.6 3114 2.94 8.2 93 93 I Bottom 3/18/08 19.2 4.85 1.6 3125 1.28 8.2 I Surface 4/19/08 23.6 10.8 1.7 3212 3.37 8.4 89 89 I Bottom 4/19/08 23.1 3.32 1.7 3209 4.77 8.5 I Surface 5/10/08 23.3 5.4 1.6 3167 0.99 7.9 87 87 I Bottom 5/10/08 22.9 4.83 1.7 3188 0.73 7.9 J Surface 1/25/08 18.6 7.45 1.5 2930 8.28 100 100 J Bottom 1/25/08 18.4 5.39 1.5 2940 8.28 J Surface 2/20/08 20.2 6.15 1.6 3087 2.68 8.3 100 100 J Bottom 2/20/08 20.1 5.77 1.6 3096 2.39 8.2 J Surface 3/18/08 19.4 4.93 1.6 3124 4.72 8.2 93 93 a Dissolved oxygen content

Table C.3. (Continued.)

J Bottom 3/18/08 19.2 4.79 1.6 3127 3.83 8.2 J Surface 4/19/08 24.0 10.87 1.7 3165 3.48 8.5 91 91 J Bottom 4/19/08 23.1 4.08 1.7 3180 6.59 8.4 J Surface 5/10/08 22.9 4.95 1.7 3202 5.8 7.9 89 89 J Bottom 5/10/08 22.7 4.61 1.7 3204 1.28 7.9 K Surface 1/25/08 18.3 6.6 1.6 2989 8.24 100 100 K Bottom 1/25/08 18.5 5.74 1.6 2995 8.24 K Surface 2/20/08 20.1 5.83 1.6 3119 3.77 8.1 102 102 K Bottom 2/20/08 20.1 5.72 1.6 3118 1.15 8.1 K Surface 3/18/08 19.3 4.86 1.6 3125 2.82 8.2 94 94 K Bottom 3/18/08 19.1 4.33 1.6 3127 5.37 8.2 K Surface 4/19/08 23.6 10.32 1.7 3210 1.78 8.4 91 91

K Bottom 4/19/08 23 6.78 1.7 3222 3.74 8.3 1

66 K Surface 5/10/08 22.9 5.16 1.7 3209 4.04 7.9 91 91

K Bottom 5/10/08 22.7 4.53 1.7 3208 1.96 7.9

Table C.4. Lake Tuendae water quality data for 2008.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) 1A Surface 1/25/08 9.6 9.70 2.1 3983 eqp. fail. 8.88 65 65 1A Bottom 1/25/08 9.2 9.65 2.2 4075 eqp. fail. 2A Surface 1/25/08 10.0 9.76 2.2 4094 eqp. fail. 8.89 118 118 2A Bottom 1/25/08 9.8 9.68 2.2 4096 eqp. fail. 3A Surface 1/25/08 10.0 9.32 2.2 4102 eqp. fail. 8.90 92 92 3A Bottom 1/25/08 9.4 9.33 2.2 4094 eqp. fail. 4A Surface 1/25/08 11.3 9.23 2.2 4107 eqp. fail. 8.90 40 40 4A Bottom 1/25/08 11.0 10.04 2.2 4101 eqp. fail. 1B Surface 1/25/08 9.2 9.43 2.2 4092 eqp. fail. 8.87 105 100 1B Bottom 1/25/08 9.1 9.40 2.2 4090 eqp. fail.

1 2B Surface 1/25/08 9.6 9.28 2.2 4096 eqp. fail. 8.88 150 135 67

2B Bottom 1/25/08 8.8 9.53 2.2 4096 eqp. fail. 3B Surface 1/25/08 9.9 9.53 2.2 4108 eqp. fail. 8.86 115 90 3B Bottom 1/25/08 9.2 9.75 2.2 4086 eqp. fail. 4B Surface 1/25/08 11.8 10.14 2.2 4104 eqp. fail. 8.96 25 25 4B Bottom 1/25/08 11.6 10.18 2.2 4099 eqp. fail. 1C Surface 1/25/08 8.9 9.37 2.2 4094 eqp. fail. 8.88 45 45 1C Bottom 1/25/08 8.7 9.12 2.2 4096 eqp. fail. 2C Surface 1/25/08 9.6 9.31 2.2 4099 eqp. fail. 8.88 120 120 2C Bottom 1/25/08 9.0 9.80 2.2 4092 eqp. fail. 3C Surface 1/25/08 9.7 9.51 2.2 4096 eqp. fail. 8.88 105 105 3C Bottom 1/25/08 9.2 9.62 2.2 4095 eqp. fail. 4C Surface 1/25/08 11.0 9.73 2.2 4097 eqp. fail. 8.92 25 25 4C Bottom 1/25/08 11.0 9.62 2.2 4089 eqp. fail. a Dissolved oxygen content equ. fail. = Equipment failure

Table C.4. (Continued.)

1D Surface 1/25/08 9.5 9.34 2.2 4091 eqp. fail. 8.91 25 25 1D Bottom 1/25/08 9.4 8.98 2.2 4089 eqp. fail. 2D Surface 1/25/08 9.6 9.47 2.2 4090 eqp. fail. 8.91 25 25 2D Bottom 1/25/08 9.6 9.4 2.2 4088 eqp. fail. 3D Surface 1/25/08 10.5 9.63 2.2 4094 eqp. fail. 8.86 30 30 3D Bottom 1/25/08 10.6 9.55 2.2 4092 eqp. fail. 4D Surface 1/25/08 10.8 9.85 2.2 4100 eqp. fail. 8.92 30 30 4D Bottom 1/25/08 10.6 9.84 2.2 4098 eqp. fail. 1E Surface 1/25/08 9.3 9.15 2.2 4098 eqp. fail. 8.86 140 120 1E Bottom 1/25/08 9.1 8.88 2.2 4088 eqp. fail. 2E Surface 1/25/08 9.5 9.31 2.2 4090 eqp. fail. 8.86 175 125 2E Bottom 1/25/08 9.0 9.38 2.2 4086 eqp. fail. 3E

1 Surface 1/25/08 9.7 9.13 2.2 4089 eqp. fail. 8.88 175 125

68 3E Bottom 1/25/08 9.1 9.42 2.2 4087 eqp. fail.

4E Surface 1/25/08 10.4 9.48 2.2 4099 eqp. fail. 8.80 150 125 4E Bottom 1/25/08 9.4 9.72 2.2 4090 eqp. fail. 1F Surface 1/25/08 9.4 9.69 2.2 4095 eqp. fail. 8.81 135 115 1F Bottom 1/25/08 9.2 9.04 2.2 4090 eqp. fail. 2F Surface 1/25/08 9.4 9.24 2.2 4087 eqp. fail. 8.87 200 130 2F Bottom 1/25/08 8.9 9.46 2.2 4086 eqp. fail. 3F Surface 1/25/08 10.1 9.45 2.2 4091 eqp. fail. 8.87 170 142 3F Bottom 1/25/08 9.1 9.74 2.2 4088 eqp. fail. 4F Surface 1/25/08 10.3 9.24 2.2 4096 eqp. fail. 8.90 125 115 4F Bottom 1/25/08 10.1 9.88 2.2 4095 eqp. fail. 2G Surface 1/25/08 9.3 9.14 2.2 4095 eqp. fail. 8.86 170 140 2G Bottom 1/25/08 9.0 9.50 2.2 4087 eqp. fail. 3G Surface 1/25/08 10.2 9.05 2.2 4090 eqp. fail. 8.87 155 138 3G Bottom 1/25/08 9.2 8.91 2.2 4085 eqp. fail.

Table C.4. (Continued.)

1A Surface 2/20/08 13.2 10.08 2.2 4116 6.19 8.50 39 39 1A Bottom 2/20/08 13.2 9.89 2.2 4115 3.57 8.50 2A Surface 2/20/08 13.0 10.14 2.2 4111 5.95 8.50 122 83 2A Bottom 2/20/08 13.0 9.95 2.2 4111 4.62 8.50 3A Surface 2/20/08 13.2 10.32 2.2 4118 5.38 8.10 133 78 3A Bottom 2/20/08 13.2 10.16 2.2 4112 4.33 8.20 4A Surface 2/20/08 13.2 10.31 2.2 4115 5.78 8.00 30 30 4A Bottom 2/20/08 13.2 10.05 2.2 4112 5.38 8.00 1B Surface 2/20/08 13.0 9.95 2.2 4109 4.53 8.60 40 40 1B Bottom 2/20/08 12.9 9.83 2.2 4108 4.50 8.50 2B Surface 2/20/08 12.8 10.50 2.2 4106 5.93 8.40 152 74 2B Bottom 2/20/08 12.8 9.92 2.2 4109 5.31 8.40

3B Surface 2/20/08 13.2 10.27 2.2 4112 3.95 8.10 100 72 1

69 3B Bottom 2/20/08 13.2 10.13 2.2 4111 4.96 8.10

4B Surface 2/20/08 13.2 10.33 2.2 4118 4.49 8.20 21 21 4B Bottom 2/20/08 13.2 10.12 2.2 4113 4.37 8.10 1C Surface 2/20/08 12.6 9.85 2.2 4102 3.77 8.60 42 42 1C Bottom 2/20/08 12.5 9.74 2.2 4104 3.89 8.60 2C Surface 2/20/08 12.7 10.04 2.2 4108 6.77 8.40 118 76 2C Bottom 2/20/08 12.7 9.98 2.2 4108 5.76 8.40 3C Surface 2/20/08 13.2 10.39 2.2 4112 7.49 8.10 97 78 3C Bottom 2/20/08 13.2 10.15 2.2 4110 9.10 8.20 4C Surface 2/20/08 13.3 10.12 2.2 4113 3.68 8.20 24 24 4C Bottom 2/20/08 13.3 9.89 2.2 4114 3.50 8.20 1D Surface 2/20/08 12.6 9.85 2.2 4105 3.81 8.60 28 28 1D Bottom 2/20/08 12.6 9.61 2.2 4104 5.02 8.50 2D Surface 2/20/08 12.8 10.27 2.2 4104 4.40 8.60 27 27 2D Bottom 2/20/08 12.8 9.97 2.2 4102 4.35 8.60

Table C.4. (Continued.)

3D Surface 2/20/08 13.1 10.31 2.2 4106 4.09 8.20 27 27 3D Bottom 2/20/08 13.2 10.18 2.2 4106 4.78 8.30 4D Surface 2/20/08 13.3 10.24 2.2 4110 4.51 8.20 29 29 4D Bottom 2/20/08 13.3 10.22 2.2 4110 5.47 8.30 1E Surface 2/20/08 12.3 9.81 2.2 4101 4.79 8.60 138 88 1E Bottom 2/20/08 12.3 9.75 2.2 4100 4.90 8.60 2E Surface 2/20/08 12.8 10.47 2.2 4089 3.80 8.50 181 91 2E Bottom 2/20/08 12.4 10.15 2.2 4097 4.30 8.50 3E Surface 2/20/08 12.9 10.33 2.2 4105 4.22 8.20 176 83 3E Bottom 2/20/08 12.8 10.09 2.2 4103 4.22 8.30 4E Surface 2/20/08 12.9 10.30 2.2 4104 4.08 8.20 168 88 4E Bottom 2/20/08 12.8 10.03 2.2 4116 6.77 8.20

1F Surface 2/20/08 12.2 10.05 2.2 4094 4.61 8.60 128 82 1

70 1F Bottom 2/20/08 11.8 9.12 2.2 4093 4.19 8.60

2F Surface 2/20/08 12.6 10.34 2.2 4100 4.08 8.40 194 88 2F Bottom 2/20/08 12.0 10.25 2.2 1095 4.27 8.40 3F Surface 2/20/08 12.9 10.28 2.2 4103 5.07 8.30 162 86 3F Bottom 2/20/08 12.6 10.14 2.2 4104 3.66 8.30 4F Surface 2/20/08 12.9 10.28 2.2 4103 3.71 8.50 118 75 4F Bottom 2/20/08 12.9 9.99 2.2 4103 3.39 8.50 2G Surface 2/20/08 12.5 10.37 2.2 4908 4.19 8.50 177 82 2G Bottom 2/20/08 12.0 10.24 2.2 4903 3.31 8.50 3G Surface 2/20/08 12.9 10.09 2.2 4102 4.11 8.40 158 78 3G Bottom 2/20/08 12.1 9.61 2.2 4092 3.78 8.50 1A Surface 3/18/08 14.0 9.98 2.3 4228 5.65 8.70 32 32 1A Bottom 3/18/08 14.1 9.92 2.3 4234 7.45 8.70 2A Surface 3/18/08 14.1 10.41 2.3 4218 6.05 8.70 108 68 2A Bottom 3/18/08 13.2 10.66 2.3 4232 5.56 8.80

Table C.4. (Continued.)

3A Surface 3/18/08 18.5 11.46 eqp. fail. 4.27 7.45 8.50 115 77 3A Bottom 3/18/08 15.0 12.53 eqp. fail. 4.18 5.25 8.80 4A Surface 3/18/08 19.1 11.77 eqp. fail. 4.22 6.67 8.50 23 23 4A Bottom 3/18/08 18.4 11.79 eqp. fail. 4.28 5.46 8.60 1B Surface 3/18/08 14.1 10.08 2.3 4240 5.15 8.80 41 41 1B Bottom 3/18/08 13.5 10.09 2.3 4242 9.31 8.80 2B Surface 3/18/08 14.6 9.93 2.3 4232 7.39 8.70 147 96 2B Bottom 3/18/08 13.2 10.13 2.3 4235 6.60 8.70 3B Surface 3/18/08 18.6 12.19 eqp. fail. 4.25 5.89 8.50 113 79 3B Bottom 3/18/08 15.7 12.80 eqp. fail. 4.07 5.58 8.80 4B Surface 3/18/08 19.8 12.38 eqp. fail. 4.21 6.88 8.50 20 20 4B Bottom 3/18/08 18.9 12.42 eqp. fail. 4.18 6.66 8.60

1C Surface 3/18/08 14.1 10.30 2.3 4220 5.27 8.80 33 33 1

71 1C Bottom 3/18/08 13.2 10.34 2.3 4228 11.48 8.80

2C Surface 3/18/08 14.9 10.04 2.3 4220 5.72 8.70 116 89 2C Bottom 3/18/08 13.3 10.53 2.3 4230 5.65 8.80 3C Surface 3/18/08 18.4 12.55 eqp. fail. 4.21 6.03 8.40 95 74 3C Bottom 3/18/08 14.6 14.10 eqp. fail. 4.22 6.61 8.50 4C Surface 3/18/08 18.3 12.27 eqp. fail. 4.17 7.88 8.40 23 23 4C Bottom 3/18/08 17.9 11.60 eqp. fail. 4.25 8.20 8.50 1D Surface 3/18/08 14.9 10.00 2.3 4225 8.28 8.80 10 10 1D Bottom 3/18/08 14.7 9.75 2.3 4220 13.08 8.80 2D Surface 3/18/08 15.4 10.38 2.3 4240 8.66 8.80 12 12 2D Bottom 3/18/08 15.3 10.31 2.3 4241 7.06 8.80 3D Surface 3/18/08 18.5 12.45 eqp. fail. 4.21 5.35 8.40 25 25 3D Bottom 3/18/08 17.7 11.89 eqp. fail. 4.22 6.89 8.50 4D Surface 3/18/08 17.9 12.17 eqp. fail. 4.21 5.18 8.50 19 19 4D Bottom 3/18/08 17.4 12.33 eqp. fail. 4.26 5.51 8.70

Table C.4. (Continued.)

1E Surface 3/18/08 13.7 9.33 2.3 4222 5.65 8.80 122 70 1E Bottom 3/18/08 13.3 9.16 2.3 4225 6.55 8.50 2E Surface 3/18/08 16.8 12.07 eqp. fail. eqp. fail. 5.78 8.70 63 77 2E Bottom 3/18/08 15.1 12.33 eqp. fail. eqp. fail. 6.02 8.70 3E Surface 3/18/08 17.4 11.24 eqp. fail. 4.2 5.16 8.60 172 90 3E Bottom 3/18/08 14.8 11.91 eqp. fail. 4.21 8.70 4E Surface 3/18/08 18.6 11.88 eqp. fail. eqp. fail. 8.46 8.60 172 88 4E Bottom 3/18/08 22.6 8.23 eqp. fail. eqp. fail. 8.19 8.70 1F Surface 3/18/08 13.9 9.42 2.3 4210 5.32 8.70 123 88 1F Bottom 3/18/08 13.2 9.63 2.3 4221 8.33 8.70 2F Surface 3/18/08 16.8 12.07 eqp. fail. eqp. fail. 5.78 8.70 63 77 2F Bottom 3/18/08 15.1 12.33 eqp. fail. eqp. fail. 6.02 8.70

3F Surface 3/18/08 17.6 11.32 eqp. fail. eqp. fail. 5.41 8.50 173 94 1 72 3F Bottom 3/18/08 14.5 11.91 eqp. fail. eqp. fail. 5.29 8.60 4F Surface 3/18/08 16.4 12.09 eqp. fail. eqp. fail. 6.48 8.60 112 72 4F Bottom 3/18/08 14.4 12.95 eqp. fail. eqp. fail. 8.66 8.70 2G Surface 3/18/08 18.0 11.53 eqp. fail. eqp. fail. 5.27 8.70 180 92 2G Bottom 3/18/08 15.0 11.66 eqp. fail. eqp. fail. 6.65 8.70 3G Surface 3/18/08 17.2 11.51 eqp. fail. eqp. fail. 5.46 8.60 88 171 3G Bottom 3/18/08 14.7 11.50 eqp. fail. eqp. fail. 6.51 8.70 1A Surface 4/19/08 20.3 13.67 2.5 4595 13.38 9.00 10 10 1A Bottom 4/19/08 20.1 14.09 2.5 4604 14.05 9.00 2A Surface 4/19/08 20.5 13.76 2.5 4587 10.18 9.00 166 67 2A Bottom 4/19/08 20.1 13.47 2.5 4593 12.64 9.00 3A Surface 4/19/08 20.6 13.96 2.5 4601 11.08 9.00 114 63 3A Bottom 4/19/08 19.1 14.83 2.5 4591 12.54 9.00 4A Surface 4/19/08 21.0 14.81 2.5 4599 12.81 9.00 28 28 4A Bottom 4/19/08 20.0 14.18 2.5 4602 14.30 9.10

Table C.4. (Continued.)

1B Surface 4/19/08 20.1 13.70 2.5 4595 14.63 9.00 24 24 1B Bottom 4/19/08 20.1 14.01 2.5 4602 14.72 9.00 2B Surface 4/19/08 20.0 13.97 2.5 4580 12.46 9.00 145 59 2B Bottom 4/19/08 19.1 13.63 2.5 4589 11.79 9.00 3B Surface 4/19/08 20.9 13.45 2.5 4579 11.43 9.00 118 67 3B Bottom 4/19/08 19.6 13.46 2.5 4577 13.69 9.00 4B Surface 4/19/08 21.1 14.36 2.5 4605 14.71 9.00 17 17 4B Bottom 4/19/08 21.1 14.52 2.5 4603 15.59 9.00 1C Surface 4/19/08 19.7 14.29 2.5 4579 14.48 9.00 27 27 1C Bottom 4/19/08 19.4 14.35 2.5 4583 16.32 9.00 2C Surface 4/19/08 20.1 14.14 2.5 4573 13.07 9.10 103 58 2C Bottom 4/19/08 19.3 14.05 2.5 4578 14.15 9.10

3C Surface 4/19/08 20.8 13.73 2.5 4630 10.84 9.00 100 53 1

73 3C Bottom 4/19/08 19.3 14.27 2.5 4506 13.61 9.00

4C Surface 4/19/08 22.0 14.71 2.5 4610 13.03 9.00 15 15 4C Bottom 4/19/08 22.1 14.54 2.5 4612 16.08 9.10 1D Surface 4/19/08 20.0 14.33 2.4 4566 17.26 9.10 18 18 1D Bottom 4/19/08 19.9 14.12 2.4 4578 14.90 9.10 2D Surface 4/19/08 20.4 15.08 2.5 4584 12.98 9.10 23 23 2D Bottom 4/19/08 20.3 15.28 2.5 4588 12.98 9.10 3D Surface 4/19/08 22.6 15.29 2.5 4609 15.85 9.10 13 13 3D Bottom 4/19/08 22.7 15.27 2.5 4615 12.95 9.10 4D Surface 4/19/08 23.9 16.51 2.5 4651 15.00 9.10 19 19 4D Bottom 4/19/08 23.7 15.87 2.5 4636 17.48 9.10 1E Surface 4/19/08 19.8 14.02 2.4 4566 12.77 9.00 112 60 1E Bottom 4/19/08 19.4 14.13 2.5 4569 12.39 9.10 2E Surface 4/19/08 19.5 14.21 2.5 4580 14.23 9.10 161 55 2E Bottom 4/19/08 19.1 13.75 2.5 4572 13.97 9.10

Table C.4. (Continued.)

3E Surface 4/19/08 21.6 13.51 2.4 4576 12.17 8.90 168 58 3E Bottom 4/19/08 19.6 13.78 2.4 4561 12.89 9.00 4E Surface 4/19/08 23.1 14.83 2.5 4621 11.04 9.00 112 52 4E Bottom 4/19/08 19.8 14.09 2.5 4570 18.72 9.00 1F Surface 4/19/08 19.3 13.98 2.4 4567 11.39 9.00 92 57 1F Bottom 4/19/08 19.2 13.76 2.5 4570 17.61 9.00 2F Surface 4/19/08 19.5 14.21 2.4 4570 11.26 9.10 179 60 2F Bottom 4/19/08 19.0 14.12 2.5 4578 14.31 9.10 3F Surface 4/19/08 21.8 13.78 2.5 4610 12.10 9.00 160 62 3F Bottom 4/19/08 19.6 14.30 2.4 4553 13.26 9.00 4F Surface 4/19/08 23.0 14.47 2.5 4610 10.88 9.10 90 55 4F Bottom 4/19/08 20.2 15.57 2.4 4564 16.13 9.00

2G Surface 4/19/08 19.5 13.71 2.4 4550 12.83 9.10 184 58 1

74 2G Bottom 4/19/08 19.0 11.88 2.4 4558 23.13 9.00

3G Surface 4/19/08 22.4 14.11 2.5 4604 12.50 9.00 150 55 3G Bottom 4/19/08 20.0 13.61 2.4 4558 12.22 9.00 1A Surface 5/10/08 24.4 12.94 2.4 4496 19.81 9.1 49 49 5/10/08 23.9 12.99 2.4 4481 15.73 9.2 1A Bottom 2A Surface 5/10/08 24.8 12.85 2.4 4486 17.63 9.10 58 151 5/10/08 22.6 12.69 2.4 4474 15.57 9.20 2A Bottom 3A Surface 5/10/08 24.6 12.74 2.4 4484 16.94 9.10 52 158 5/10/08 22.7 12.04 2.4 4469 18.49 9.20 3A Bottom 4A Surface 5/10/08 24.9 13.33 2.4 4484 14.69 9.10 48 48 5/10/08 24.5 15.86 2.4 4499 11.52 9.20 4A Bottom 1B Surface 5/10/08 24.1 12.25 2.4 4490 11.57 9.10 48 48 5/10/08 23.6 11.86 2.4 4478 15.22 9.10 1B Bottom 2B Surface 5/10/08 24.3 12.23 2.4 4482 11.99 9.10 65 170 2B Bottom 5/10/08 22.6 11.58 2.4 4475 12.2 9.20

Table C.4. (Continued.)

3B Surface 5/10/08 25.1 14.95 2.4 4486 10.54 9.10 60 140 5/10/08 23 14.16 2.4 4465 11.19 9.20 3B Bottom 4B Surface 5/10/08 25 14.86 2.4 4486 17.45 9.10 33 33 5/10/08 24.8 15.74 2.4 4482 13.62 9.20 4B Bottom 1C Surface 5/10/08 24 12.99 2.4 4479 11.57 9.10 38 38 5/10/08 23.7 12.64 2.4 4483 16.23 9.20 1C Bottom 2C Surface 5/10/08 24.1 12.57 2.4 4498 13.39 9.10 62 132 5/10/08 22.7 11.54 2.4 4472 10.7 9.20 2C Bottom 3C Surface 5/10/08 25 12.7 2.4 44.88 10.97 9.10 57 122 5/10/08 23.5 13.38 2.4 4496 11.09 9.20 3C Bottom 4C Surface 5/10/08 25.3 14.32 2.4 4519 16.34 9.10 38 38 5/10/08 24.3 14.5 2.4 4488 15.53 9.20 4C Bottom

1D Surface 5/10/08 24.1 12.71 2.4 4477 11.17 9.10 38 38 1 75 1D Bottom 5/10/08 23.8 13.88 2.4 4486 11.34 9.20

2D Surface 5/10/08 24.3 12.72 2.4 4448 11.81 9.10 44 44 5/10/08 24.2 13.33 2.4 4450 10.91 9.20 2D Bottom 3D Surface 5/10/08 25.7 13.69 2.4 4468 10.18 9.00 44 44 5/10/08 25.6 14.15 2.4 4478 11.68 9.10 3D Bottom 4D Surface 5/10/08 25.8 15.21 2.4 4479 15.13 9.10 36 36 5/10/08 25.7 14.69 2.4 4481 18.32 9.20 4D Bottom 1E Surface 5/10/08 24.1 11.88 2.4 4432 9.43 9.10 64 168 5/10/08 23 12.75 2.4 4558 13.58 9.20 1E Bottom 2E Surface 5/10/08 24.1 12.42 2.4 4440 11.25 9.10 72 180 5/10/08 23.1 13.17 2.4 4564 12.49 9.20 2E Bottom 3E Surface 5/10/08 26.1 12.99 2.4 4478 10.57 9.00 63 200 5/10/08 22.9 13.75 2.4 4577 12.32 9.10 3E Bottom 4E Surface 5/10/08 26 12.47 2.4 4444 10.18 9.10 55 168 4E Bottom 5/10/08 22.8 15.07 2.4 4558 11.82 9.10

Table C.4. (Continued.)

1F Surface 5/10/08 23.9 12.07 2.4 4456 12.83 9.10 72 139 5/10/08 22.9 12.67 2.4 4561 11.9 9.10 1F Bottom 2F Surface 5/10/08 24 12.24 2.4 4441 9.7 9.10 78 197 5/10/08 22.7 11.66 2.5 4571 11.68 9.10 2F Bottom 3F Surface 5/10/08 26.5 12.49 2.4 4472 10.02 9.00 58 195 5/10/08 22.9 15.65 2.5 4494 13.75 9.10 3F Bottom 4F Surface 5/10/08 26.3 12.55 2.3 4400 9.23 9.00 58 138 5/10/08 23.3 13.9 2.4 4464 11.07 9.10 4F Bottom 2G Surface 5/10/08 22.2 12.16 2.4 4434 12 9.10 68 193 5/10/08 22.7 10.36 2.5 4593 12.19 9.20 2G Bottom 3G Surface 5/10/08 26.9 12.23 2.4 44.63 10.67 9.00 62 189

3G Bottom 5/10/08 23.4 12.93 2.4 4559 13.74 9.10 1

Table C.5. MC Spring water quality data for 2009.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) H Surface 3/17/05 23 8.91 1.7 3233 3.39 7.9 80 80 H Bottom 3/17/05 22.5 6.32 1.7 3225 3.41 7.9 H Surface 4/17/05 24.4 7.57 1.7 3556 5.04 7.9 80 80 H Bottom 4/17/05 23.7 7.57 1.7 3200 5.19 7.9 H Surface 5/12/05 26.3 10.58 1.7 3280 2.41 8.3 79 79 H Bottom 5/12/05 26.3 10.52 1.7 3261 1.41 8.3 I Surface 3/17/05 22.6 8.63 1.7 3217 1.85 7.9 80 80 I Bottom 3/17/05 22.5 8.61 1.7 3222 3.72 7.9 I Surface 4/17/05 23.8 8.09 1.7 3217 1.64 7.9 76 76 I Bottom 4/17/05 23.7 8.13 1.7 3219 3.51 7.9

1 I

77 Surface 5/12/05 25.8 10.44 1.7 3222 6.06 8.3 73 73

I Bottom 5/12/05 25.8 9.41 1.7 3218 1.95 8.3 J Surface 3/17/05 22.6 8.32 1.7 3215 0.58 7.9 75 75 J Bottom 3/17/05 22.6 8.23 1.7 3216 1.29 7.9 J Surface 4/17/05 23.8 8.42 1.7 3143 1.24 7.9 76 76 J Bottom 4/17/05 23.1 9.28 1.7 3204 2.97 7.9 J Surface 5/12/05 25.8 9.79 1.7 3244 2.48 8.2 78 78 J Bottom 5/12/05 25.8 9.39 1.7 3221 0.82 8.2 K Surface 3/17/05 22.7 8.43 1.7 3219 1.05 7.9 75 75 K Bottom 3/17/05 22.7 8.13 1.7 3218 1.39 7.9 K Surface 4/17/05 23.8 8.64 1.7 3220 2.06 7.9 75 75 K Bottom 4/17/05 23.4 8.37 1.7 3140 2.15 7.9 K Surface 5/12/05 26 9.84 1.7 3237 1.61 8.2 75 75 K Bottom 5/12/05 25.6 9.98 1.7 3233 0.93 8.2 a Dissolved oxygen content shallow = water depth was too low to measure the water quality data.

Table C.6. Lake Tuendae water quality data for 2009.

Transect Depth Date Temperature DOa Salinity Specific Turbidity pH Secchi Depth (C0) (mg/L) (ppt) Conductivity (µS) (NTU) depth (cm) (cm) 1A Surface 3/17/05 18.0 11.74 2.3 4254 4.53 8.3 80 111 1A Bottom 3/17/05 16.5 11.80 2.3 4238 6.85 8.3 2A Surface 3/17/05 17.9 11.60 2.3 4245 5.07 8.7 90 135 2A Bottom 3/17/05 16.5 11.64 2.3 4246 9.68 8.7 3A Surface 3/17/05 17.4 11.43 2.3 4255 6.10 8.7 70 140 3A Bottom 3/17/05 16.4 11.66 2.3 4243 7.84 8.7 4A Surface 3/17/05 17.8 11.01 2.3 3860 5.47 8.6 59 59 4A Bottom 3/17/05 17.2 8.65 2.3 4234 6.72 8.6 1B Surface 3/17/05 18.2 11.90 2.3 4256 5.76 8.3 80 145 1B Bottom 3/17/05 16.7 11.89 2.3 4245 6.33 8.3

1 2B Surface 3/17/05 18.3 12.07 2.3 4251 5.87 8.3 81 140 78

2B Bottom 3/17/05 17.0 11.69 2.3 4248 5.43 8.3 3B Surface 3/17/05 18.6 11.68 2.3 4262 5.28 8.3 80 115 3B Bottom 3/17/05 16.6 12.80 2.3 4246 5.34 8.3 4B Surface 3/17/05 19.5 13.40 2.3 4280 5.72 8.3 22 22 4B Bottom 3/17/05 shallow shallow shallow shallow shallow shallow 1C Surface 3/17/05 20.2 11.84 2.3 4280 5.16 8.3 80 100 1C Bottom 3/17/05 17.1 12.86 2.3 4239 6.53 8.3 2C Surface 3/17/05 19.9 12.00 2.3 4264 4.33 8.3 80 101 2C Bottom 3/17/05 17.1 13.32 2.3 4243 5.85 8.3 3C Surface 3/17/05 19.3 12.16 2.3 4272 4.91 8.3 79 79 3C Bottom 3/17/05 17.0 13.50 2.3 4242 6.93 8.3 4C Surface 3/17/05 19.4 12.76 2.3 4260 4.66 8.3 44 44 4C Bottom 3/17/05 shallow shallow shallow shallow shallow shallow a Dissolved oxygen content shallow = water depth was too low to measure the water quality data.

Table C.6. (Continued).

1D Surface 3/17/05 20.4 12.10 2.3 4245 4.42 8.2 79 79 1D Bottom 3/17/05 16.8 14.60 2.3 4228 4.42 8.2 2D Surface 3/17/05 19.4 12.84 2.3 4240 5.46 8.2 30 30 2D Bottom 3/17/05 shallow shallow shallow shallow shallow shallow 3D Surface 3/17/05 19.4 12.65 2.3 4241 8.2 26 26 3D Bottom 3/17/05 shallow shallow shallow shallow shallow shallow 4D Surface 3/17/05 20.1 13.52 2.3 4245 4.85 8.3 31 31 4D Bottom 3/17/05 shallow shallow shallow shallow shallow shallow 1E Surface 3/17/05 20.2 12.15 2.3 4274 4.79 8.2 75 200 1E Bottom 3/17/05 17.0 12.28 2.3 4231 6.69 8.2 2E Surface 3/17/05 20.2 12.17 2.3 4243 4.85 8.2 75 182 2E Bottom 3/17/05 17.1 12.69 2.3 4227 8.13 8.2

3E Surface 3/17/05 19.8 11.90 2.3 4265 5.38 8.2 90 175 1 79 3E Bottom 3/17/05 17.2 12.65 2.3 4225 5.61 8.2 4E Surface 3/17/05 20.3 12.21 2.3 4276 4.58 8.3 80 170 4E Bottom 3/17/05 17.6 12.96 2.3 4217 7.68 8.3 1F Surface 3/17/05 21.1 11.97 2.3 4261 5.22 8.5 90 150 1F Bottom 3/17/05 17.2 13.05 2.3 4236 7.50 8.5 2F Surface 3/17/05 21.0 11.91 2.3 4266 4.34 8.6 80 190 2F Bottom 3/17/05 16.9 12.09 2.3 4230 5.25 8.6 3F Surface 3/17/05 21.5 11.89 2.3 4287 4.03 8.2 80 165 3F Bottom 3/17/05 17.0 13.53 2.3 4227 5.77 8.2 4F Surface 3/17/05 21.2 12.07 2.3 4268 5.59 8.6 80 140 4F Bottom 3/17/05 17.1 14.22 2.3 4230 8.6 2G Surface 3/17/05 21.7 11.50 2.3 4281 5.74 8.6 80 181 2G Bottom 3/17/05 17.2 11.58 2.3 4225 5.43 8.6

Table C.6. (Continued).

3G Surface 3/17/05 21.3 11.84 2.3 4270 5.69 8.2 87 140 3G Bottom 3/17/05 17.0 12.13 2.3 4225 6.18 8.2 1A Surface 4/25/05 20.7 12.73 2.3 4396 9.40 8.9 65 65 1A Bottom 4/25/05 20.6 11.20 2.3 4334 14.79 8.9 2A Surface 4/25/05 20.6 11.75 2.4 4400 11.29 8.9 78 130 2A Bottom 4/25/05 18.3 12.89 2.3 4380 13.37 8.9 3A Surface 4/25/05 21.1 11.80 2.4 4405 11.10 8.9 90 130 3A Bottom 4/25/05 18.4 13.25 2.4 4378 11.33 8.9 4A Surface 4/25/05 21.7 12.17 2.3 4420 10.65 8.9 50 50 4A Bottom 4/25/05 21.1 11.77 2.3 4338 13.52 8.9 1B Surface 4/25/05 21.4 12.60 2.4 4425 9.25 8.9 62 62 1B Bottom 4/25/05 18.8 13.07 2.4 4396 11.55 8.9

2B Surface 4/25/05 20.9 12.52 2.4 4418 9.62 9.0 70 140

1 8

0 2B Bottom 4/25/05 18.9 12.50 2.4 4394 10.32 9.0 3B Surface 4/25/05 20.7 12.44 2.4 4400 10.96 8.9 80 110 3B Bottom 4/25/05 18.4 14.18 2.3 4382 20.96 8.9 4B Surface 4/25/05 20.8 13.08 2.3 4407 11.06 9.0 15 15 4B Bottom 4/25/05 shallow shallow shallow shallow shallow shallow 1C Surface 4/25/05 21.2 12.65 2.4 4423 9.47 8.9 70 95 1C Bottom 4/25/05 18.7 14.97 2.4 4389 11.72 8.9 2C Surface 4/25/05 21.4 12.74 2.4 4429 9.64 8.9 75 103 2C Bottom 4/25/05 18.7 14.27 2.4 3870 12.74 8.9 3C Surface 4/25/05 21.5 12.78 2.4 4422 9.22 8.9 70 90 3C Bottom 4/25/05 18.8 14.85 2.4 4399 10.80 8.9 4C Surface 4/25/05 21.6 13.67 2.3 4422 9.13 8.9 40 40 4C Bottom 4/25/05 21.4 11.43 2.3 4323 11.62 8.9

Table C.6. (Continued).

1D Surface 4/25/05 22.0 13.23 2.3 4429 11.64 8.9 80 109 1D Bottom 4/25/05 18.5 15.99 2.3 4386 10.49 8.9 2D Surface 4/25/05 21.7 12.52 2.4 4412 9.00 8.9 2D Bottom 4/25/05 18.1 13.34 2.4 4377 10.78 8.9 3D Surface 4/25/05 21.5 13.92 2.3 4400 9.41 9.0 25 25 3D Bottom 4/25/05 shallow shallow shallow shallow shallow shallow 4D Surface 4/25/05 22.5 14.29 2.4 4410 8.03 9.0 20 20 4D Bottom 4/25/05 shallow shallow shallow shallow shallow shallow 1E Surface 4/25/05 21.8 12.90 2.4 4412 8.18 8.9 70 190 1E Bottom 4/25/05 18.3 12.55 2.4 4381 13.74 8.9 2E Surface 4/25/05 21.3 12.02 2.4 4420 9.30 8.9 85 182 2E Bottom 4/25/05 18.1 13.00 2.4 4376 11.20 8.9

3E Surface 4/25/05 21.1 12.01 2.3 4419 10.17 8.9 75 180 1

81 3E Bottom 4/25/05 18.2 13.60 2.3 4371 11.17 8.9 4E Surface 4/25/05 20.6 12.36 2.4 4409 9.87 8.9 80 170 4E Bottom 4/25/05 18.3 14.22 2.4 4362 11.52 8.9 1F Surface 4/25/05 22.0 12.11 2.3 4428 8.95 8.9 75 132 1F Bottom 4/25/05 18.6 13.27 2.3 4376 9.50 8.9 2F Surface 4/25/05 21.0 12.55 2.3 4420 10.23 8.9 81 175 2F Bottom 4/25/05 18.0 12.56 2.3 4360 9.29 8.9 3F Surface 4/25/05 20.9 12.47 2.4 4059 10.09 8.9 80 160 3F Bottom 4/25/05 18.3 13.47 2.4 3806 11.85 8.9 4F Surface 4/25/05 20.9 12.44 2.3 4402 9.99 8.9 80 162 4F Bottom 4/25/05 18.3 13.42 2.3 4367 9.81 8.9 2G Surface 4/25/05 21.4 12.63 2.3 4422 9.64 8.9 75 163 2G Bottom 4/25/05 18.5 11.86 2.3 4370 8.75 8.9

Table C.6. (Continued).

3G Surface 4/25/05 21.2 12.69 2.3 4400 8.94 8.9 70 140 3G Bottom 4/25/05 18.3 12.17 2.3 4375 11.36 8.9 1A Surface 5/12/05 26.3 12.34 2.4 4585 11.26 9.3 55 108 1A Bottom 5/12/05 26.3 12.34 2.4 4585 21.57 9.3 2A Surface 5/12/05 26.5 12.93 2.4 4602 13.10 9.1 53 145 2A Bottom 5/12/05 26.5 12.93 2.4 4602 15.20 9.1 3A Surface 5/12/05 26.1 12.24 2.4 4590 14.15 9.1 54 142 3A Bottom 5/12/05 26.1 12.24 2.4 4590 13.70 9.1 4A Surface 5/12/05 27.1 12.20 2.4 4600 16.33 9.2 54 54 4A Bottom 5/12/05 27.1 12.20 2.4 4600 31.57 9.2 1B Surface 5/12/05 27.1 11.27 2.4 4604 12.85 9.1 55 90 1B Bottom 5/12/05 27.1 11.27 2.4 4604 12.85 9.1

2B Surface 5/12/05 26.9 12.39 2.4 4598 11.82 9.2 55 162 1

82 2B Bottom 5/12/05 26.9 12.39 2.4 4598 10.68 9.2

3B Surface 5/12/05 27.0 12.35 2.4 4604 11.25 9.2 52 125 3B Bottom 5/12/05 27.0 12.35 2.4 4604 12.63 9.2 4B Surface 5/12/05 27.3 15.54 2.4 4602 18.65 9.2 39 39 4B Bottom 5/12/05 27.3 15.54 2.4 4602 18.65 9.2 1C Surface 5/12/05 27.5 11.02 2.4 4591 10.03 9.1 58 58 1C Bottom 5/12/05 27.5 11.02 2.4 4591 10.03 9.1 2C Surface 5/12/05 27.2 12.25 2.4 4607 11.83 9.1 52 115 2C Bottom 5/12/05 27.2 12.25 2.4 4607 11.87 9.1 3C Surface 5/12/05 27.4 11.76 2.4 4533 8.81 9.1 58 98 3C Bottom 5/12/05 27.4 11.76 2.4 4528 30.15 9.1 4C Surface 5/12/05 27.4 12.98 2.4 4587 20.92 9.1 33 33 4C Bottom 5/12/05 27.4 12.98 2.4 4498 20.92 9.1

Table C.6. (Continued).

1D Surface 5/12/05 27.3 12.08 2.4 4771 10.85 9.0 52 110 1D Bottom 5/12/05 27.3 12.08 2.4 4671 10.86 9.0 2D Surface 5/12/05 27.4 10.46 2.4 4589 11.77 8.9 56 85 2D Bottom 5/12/05 27.4 10.46 2.4 4509 12.77 8.9 3D Surface 5/12/05 27.5 10.82 2.4 4584 16.69 9.1 33 33 3D Bottom 5/12/05 27.5 10.82 2.4 4567 16.69 9.1 4D Surface 5/12/05 27.4 11.08 2.4 4572 10.38 9.0 35 35 4D Bottom 5/12/05 27.4 11.08 2.4 4598 10.38 9.0 1E Surface 5/12/05 27.9 10.76 2.4 4609 10.89 9.0 56 188 1E Bottom 5/12/05 27.9 10.76 2.4 4613 10.73 9.0 2E Surface 5/12/05 27.8 11.62 2.4 4589 10.86 9.0 54 187 2E Bottom 5/12/05 27.8 11.62 2.4 4521 13.11 9.0

3E Surface 5/12/05 27.6 10.65 2.4 4583 8.30 9.1 58 189 1

83 3E Bottom 5/12/05 27.6 10.65 2.4 4556 9.87 9.1

4E Surface 5/12/05 27.5 10.21 2.4 4546 10.41 9.0 55 178 4E Bottom 5/12/05 27.5 10.21 2.4 4544 11.64 9.0 1F Surface 5/12/05 28.1 9.85 2.4 4609 10.61 9.0 51 135 1F Bottom 5/12/05 28.1 9.85 2.4 4623 16.92 9.0 2F Surface 5/12/05 28.2 10.70 2.4 4609 8.86 9.0 58 200 2F Bottom 5/12/05 28.2 10.70 2.4 10.68 9.0 3F Surface 5/12/05 28.0 10.76 2.4 4577 8.75 9.0 58 168 3F Bottom 5/12/05 28.0 10.76 2.4 4577 9.78 9.0 4F Surface 5/12/05 27.8 9.92 2.4 4584 9.70 9.0 55 129 4F Bottom 5/12/05 27.8 9.92 2.4 4584 8.26 9.0 2G Surface 5/12/05 28.1 10.51 2.4 4605 10.87 9.1 58 175 2G Bottom 5/12/05 28.1 10.51 2.4 4605 8.88 9.1 3G Surface 5/12/05 28.0 10.88 2.4 4600 9.97 9.1 59 180 3G Bottom 5/12/05 28.0 10.88 2.4 4600 8.26 9.1

Table D.1. MC Spring aquatic invertebrate data for 2007 (number/L).

APPENDIXD

Transect Depth Date Nauplii

Rotifera Cladocera Ostracods Calanoids Cyclopids Chironomids Water mites Diptera Ephemeroptera Hemiptera Nematoda Odonata larva Oligochaeta Collembola Plecoptera Amphipods Trichoptera Thysanoptera H Surface 1/25/07 2 5 2 0 0 1 0 1 0 0 0 1 0 0 0 0 0 0 0 H Bottom 1/25/07 11 15 1 0 3 2 0 0 0 0 0 4 0 0 0 0 0 0 0

H Surface 2/5/07 3 7 5 0 0 9 0 0 0 0 0 1 0 7 0 0 0 0 0 . .

H Bottom 2/5/07 8 23 6 0 0 20 0 0 0 0 0 1 0 58 0 1 0 0 0 AQUATITICINVERTEBRA H Surface 2/23/07 59 15 11 0 6 2 0 0 0 0 0 1 0 1 0 0 0 0 0 H Bottom 2/23/07 16 11 9 0 0 4 0 0 0 0 0 2 0 4 0 0 0 0 0

H Surface 3/8/07 18 13 4 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1

84 H Bottom 3/8/07 28 16 4 2 0 2 0 0 1 1 0 0 0 0 0 0 0 0 0

H Surface 3/22/07 20 47 47 0 13 4 1 3 7 0 1 0 0 0 0 0 0 0 0 H Bottom 3/22/07 78 47 10 0 8 2 0 2 0 0 0 0 0 0 0 0 0 0 0 H Surface 4/6/07 338 13 5 0 0 6 2 0 0 0 0 1 0 2 0 0 0 0 0 H Bottom 4/6/07 685 34 23 0 0 17 1 0 0 0 0 1 0 7 0 0 0 0 0 H Surface 5/3/07 360 25 3 1 0 14 1 0 1 0 0 1 0 0 0 0 0 0 0 H Bottom 5/3/07 448 34 5 0 0 19 2 0 0 0 0 0 0 1 0 0 0 0 0 I Surface 1/25/07 0 53 3 0 1 4 0 0 0 0 0 18 0 1 0 0 0 0 0

I Bottom 1/25/07 3 22 3 0 0 3 1 0 0 0 0 7 0 2 0 0 0 0 0 DATA TE I Surface 2/5/07 20 15 9 0 2 22 2 1 0 0 0 0 0 0 0 0 0 0 0 I Bottom 2/5/07 6 26 13 1 6 96 2 1 0 0 0 1 0 6 0 0 0 0 0 I Surface 2/23/07 109 1 12 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0

I Bottom 2/23/07 10 20 7 0 1 10 0 0 0 0 0 0 0 14 0 0 0 0 0 I Surface 3/8/07 31 19 12 0 2 9 0 1 5 0 0 0 0 0 0 0 0 0 0 I Bottom 3/8/07 65 58 3 0 7 6 1 0 2 2 0 0 0 0 0 1 0 0 0

Table D.1. (Continued.)

I Surface 3/22/07 69 154 44 0 25 6 1 13 1 0 0 0 0 0 0 0 0 0 0 I Bottom 3/22/07 48 58 14 2 21 1 1 3 0 0 0 0 0 0 0 0 0 0 0 I Surface 39178 259 14 14 0 0 3 3 2 0 0 0 0 0 0 0 0 0 0 0 I Bottom 39178 111 56 3 0 1 8 1 0 0 0 0 0 0 1 0 0 0 0 0 I Surface 39205 241 31 3 0 0 18 2 0 0 0 0 0 0 2 0 0 0 0 0 I Bottom 39205 232 29 1 0 0 7 0 1 0 0 0 0 0 1 0 0 0 0 0 J Surface 39107 0 38 4 1 0 0 1 0 0 0 0 8 0 0 0 0 0 0 0 J Bottom 39107 2 29 4 0 1 4 0 0 0 0 0 2 0 2 0 0 0 0 0 J Surface 39118 13 56 13 0 0 14 0 2 0 0 0 8 0 18 0 0 0 1 0 J Bottom 39118 11 96 35 1 0 57 1 2 0 0 0 3 0 6 0 0 0 0 0 J Surface 39136 19 2 26 0 0 6 1 2 0 0 0 1 0 10 0 0 0 0 0 J Bottom 39136 83 9 18 0 0 19 0 1 0 0 0 3 0 16 0 0 0 0 0 J Surface 39149 42 45 69 0 0 25 1 0 25 4 1 0 1 0 0 0 0 0 0

1 J Bottom 39149 39 59 104 4 1 80 3 7 79 4 0 0 0 0 0 0 0 0 0 85

J Surface 39163 47 27 6 1 10 3 0 3 3 0 0 0 0 0 0 0 0 0 0 J Bottom 39163 195 73 49 0 100 12 0 40 9 0 0 0 0 0 0 0 0 0 0 J Surface 39178 222 53 43 0 1 15 4 1 1 0 0 0 0 30 0 0 0 0 0 J Bottom 39178 192 35 29 0 3 12 1 3 0 0 0 0 0 3 0 0 0 0 0 J Surface 39205 371 33 2 0 0 11 2 1 0 0 0 3 0 1 0 0 0 0 0 J Bottom 39205 395 62 11 3 0 80 1 0 0 0 0 2 0 8 0 0 0 0 0 K Surface 39107 1 7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 K Bottom 39107 1 17 1 0 0 2 0 1 0 0 0 2 0 3 0 0 0 0 0 K Surface 39118 19 26 13 0 0 6 0 0 0 0 0 3 0 10 0 0 0 0 0 K Bottom 39118 8 40 10 0 2 15 0 0 0 0 0 3 0 4 0 0 0 0 0 K Surface 39136 9 9 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 K Bottom 39136 29 44 16 0 0 14 0 0 0 0 0 0 0 6 0 0 0 0 0

Table D.1. (Continued.)

K Surface 39149 79 26 9 0 0 7 0 1 14 4 0 0 0 0 0 0 0 0 0 K Bottom 39149 58 31 21 0 8 9 1 2 9 0 0 0 0 0 0 0 0 0 0 K Surface 39163 25 27 5 1 3 0 0 0 1 0 0 0 0 0 0 0 0 0 0 K Bottom 39163 10 24 11 0 6 1 0 8 1 0 0 0 0 0 0 0 0 0 0 K Surface 39178 229 18 20 0 0 6 0 0 0 0 0 0 0 0 0 0 0 0 0 K Bottom 39178 149 25 25 0 2 27 4 1 1 0 0 4 0 7 0 0 0 0 0 K Surface 39205 279 21 3 0 0 9 2 3 0 0 0 2 0 0 0 0 0 0 0 K Bottom 39205 376 135 32 1 2 136 25 1 0 0 0 15 0 25 0 0 0 0 1

Table D.2. Lake Tuendae aquatic invertebrate data for 2007 (number/L).

Calanoids Cyclopids

Transect Depth Date Nauplii

Rotifera Cladocera Ostracods Chironomids Water mites Ephemeroptera Hemiptera Nematoda Odonata larva Oligochaeta Collembola Plecoptera Amphipods Trichoptera Thysanoptera 1A Combined 1/25/07 1 2 0 0 0 2 0 0 0 0 2 0 0 0 0 0 0 0 2A Combined 1/25/07 559 28 0 0 8 1 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 1/25/07 297 25 0 0 6 2 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 1/25/07 29 3 1 0 0 38 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 1/25/07 33 2 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 2B Combined 1/25/07 196 24 0 0 5 1 0 0 0 0 2 0 0 0 0 0 0 0 3B Combined 1/25/07 650 30 0 0 23 2 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 1/25/07 427 10 3 0 4 20 1 1 0 0 1 0 0 0 0 0 0 0

1 1C Combined 1/25/07 9 3 0 0 0 10 0 1 0 0 2 0 0 1 0 0 0 1 87

2C Combined 1/25/07 429 11 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 1/25/07 601 18 0 0 15 2 0 1 0 0 0 0 0 0 0 0 0 0 4C Combined 1/25/07 103 6 0 0 0 5 2 0 0 0 0 0 0 0 0 0 0 0 1D Combined 1/25/07 3 8 0 0 3 4 0 0 0 0 1 0 0 0 0 0 0 0 2D Combined 1/25/07 330 26 0 0 15 8 1 1 0 0 0 0 0 0 0 0 0 0 3D Combined 1/25/07 163 32 0 0 11 2 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 1/25/07 760 3 0 0 0 7 1 4 0 0 0 0 0 0 0 0 0 0 1E Surface 1/25/07 7 6 0 0 0 10 0 0 0 0 0 0 0 1 0 0 0 0 1E Bottom 1/25/07 34 11 0 0 0 19 0 0 0 0 0 0 0 0 0 1 0 1 2E Surface 1/25/07 143 19 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 2E Bottom 1/25/07 206 37 1 0 6 0 0 0 0 0 0 0 0 0 0 0 0 1 3E Surface 1/25/07 58 19 0 0 2 2 0 0 0 0 0 0 0 0 0 0 0 1 3E Bottom 1/25/07 259 48 0 0 10 2 0 0 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

4E Surface 1/25/07 209 3 5 0 1 7 0 2 0 0 0 0 0 0 0 0 0 0 4E Bottom 1/25/07 258 4 0 0 9 15 2 2 0 0 0 0 0 0 0 0 0 0 1F Surface 1/25/07 0 0 0 0 1 16 0 3 0 0 0 0 0 0 0 0 0 0 1F Bottom 1/25/07 33 7 1 6 1 18 0 6 0 0 0 0 0 0 0 0 0 0 2F Surface 1/25/07 101 12 0 0 4 1 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 1/25/07 409 40 0 0 6 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 1/25/07 60 4 0 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 1/25/07 388 15 0 1 9 2 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 1/25/07 270 6 0 0 1 9 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 1/25/07 6 3 6 0 72 15 0 0 0 0 0 0 0 1 0 0 1 0 2G Surface 1/25/07 82 10 0 0 3 7 0 13 0 0 0 0 0 0 0 0 0 0 2G Bottom 1/25/07 429 33 1 0 1 7 0 10 0 0 0 0 0 0 0 0 0 0

3G Surface 1/25/07 57 7 1 1 1 2 0 2 0 0 0 0 0 1 0 0 0 0 1

88 3G Bottom 1/25/07 132 15 0 0 9 2 0 3 0 0 0 0 0 0 0 0 0 0

1A Combined 2/5/07 2057 53 5 8 6 100 0 0 0 0 2 0 0 0 0 0 0 0 2A Combined 2/5/07 2619 30 0 3 15 22 0 0 0 0 2 0 0 0 0 0 0 0 4A Combined 2/5/07 500 11 0 23 8 50 3 0 0 0 0 0 0 0 0 0 0 0 1B Combined 2/5/07 1975 35 1 0 1 25 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 2/5/07 1677 24 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 2/5/07 159 3 1 16 0 35 8 2 0 0 0 0 0 0 0 0 0 0 1C Combined 2/5/07 474 21 1 0 3 21 0 1 0 0 0 0 0 0 0 0 0 0 2C Combined 2/5/07 450 50 0 1 21 5 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 2/5/07 684 5 2 7 1 35 3 0 0 0 0 0 0 0 0 0 0 0 1D Combined 2/5/07 459 17 4 6 1 36 1 1 0 0 1 0 0 0 0 0 0 0 2D Combined 2/5/07 173 24 0 0 17 1 1 0 0 0 0 0 0 0 0 0 0 0 4D Combined 2/5/07 62 13 2 1 0 32 11 0 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

1E Surface 2/5/07 300 8 3 0 0 6 0 2 0 0 0 0 0 0 0 0 0 0 1E Bottom 2/5/07 100 5 0 29 4 200 9 1 0 0 2 1 0 0 0 1 0 0 2E Surface 2/5/07 574 36 1 0 6 4 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 2/5/07 721 70 0 1 18 22 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 2/5/07 180 10 0 0 6 54 1 0 0 0 1 0 0 0 0 0 0 0 4E Bottom 2/5/07 206 20 0 4 30 28 2 0 0 0 0 0 0 0 0 0 0 0 1F Surface 2/5/07 107 14 0 0 1 0 1 2 0 0 0 0 0 0 0 0 0 0 1F Bottom 2/5/07 128 24 0 90 4 68 1 0 0 0 0 0 0 0 0 0 0 0 2F Surface 2/5/07 175 21 1 0 5 6 0 0 0 0 0 0 0 1 0 0 0 0 2F Bottom 2/5/07 282 60 0 0 12 8 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 2/5/07 422 21 0 1 0 13 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 2/5/07 568 20 0 1 20 41 17 0 0 0 0 0 0 0 0 0 0 0

2G Surface 2/5/07 197 21 0 0 4 5 0 0 0 0 0 0 0 0 0 0 0 0 1

89 2G Bottom 2/5/07 645 39 0 0 5 3 0 0 0 0 0 0 0 0 0 0 0 0

1A Combined 2/23/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 2/23/07 677 88 0 0 9 4 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 2/23/07 1294 370 0 0 60 0 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 2/23/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 2/23/07 318 204 0 0 2 5 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 2/23/07 311 261 0 0 38 1 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 2/23/07 2032 497 1 0 46 0 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 2/23/07 2704 71 2 4 0 4 0 1 0 0 0 0 0 0 0 0 0 0 1C Combined 2/23/07 627 222 0 2 4 1 0 0 0 0 0 0 0 0 0 0 0 0 2C Combined 2/23/07 517 262 0 0 13 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 2/23/07 2248 255 0 0 25 0 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 2/23/07 9260 50 16 21 3 1 0 1 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

1D Combined 2/23/07 214 303 0 1 7 4 0 1 0 0 0 0 0 0 0 0 0 0 2D Combined 2/23/07 2352 311 1 0 70 0 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 2/23/07 3156 319 0 0 47 7 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 2/23/07 2716 219 4 1 1 4 0 0 0 0 0 0 0 0 0 0 0 0 1E Surface 2/23/07 72 299 2 1 2 4 0 1 0 0 0 0 0 0 0 0 0 0 1E Bottom 2/23/07 2076 379 0 22 16 91 0 0 0 0 0 0 0 0 0 0 0 0 2E Surface 2/23/07 277 277 1 0 20 0 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 2/23/07 1164 235 3 0 27 1 0 0 0 0 0 0 0 0 0 0 0 0 3E Surface 2/23/07 1556 411 0 0 24 3 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 2/23/07 1953 551 0 0 55 0 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 2/23/07 1223 212 0 0 4 11 1 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 2/23/07 2036 189 6 1 11 16 2 0 0 0 0 1 0 0 0 0 0 0

1F Surface 2/23/07 164 211 24 0 1 16 0 1 0 0 0 0 0 0 0 0 0 0 1

90 1F Bottom 2/23/07 132 235 0 47 2 51 0 0 0 0 0 0 0 0 0 0 0 1

2F Surface 2/23/07 142 422 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 2/23/07 705 304 1 0 22 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 2/23/07 309 298 0 0 11 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 2/23/07 1328 375 0 0 56 2 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 2/23/07 902 163 0 0 16 5 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 2/23/07 688 152 4 5 5 8 2 1 0 0 0 0 0 0 0 0 0 0 2G Surface 2/23/07 74 178 0 1 2 4 0 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 2/23/07 1904 224 1 0 12 0 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 2/23/07 163 109 1 0 0 3 1 0 0 0 1 0 0 0 0 0 0 0 3G Bottom 2/23/07 439 295 0 1 26 1 0 0 0 0 0 0 0 0 0 0 0 0 1A Combined 3/8/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 3/8/07 1592 326 0 0 104 1 0 0 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

3A Combined 3/8/07 3000 467 0 0 117 1 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 3/8/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 3/8/07 195 152 0 0 4 3 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 3/8/07 1660 306 1 0 69 0 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 3/8/07 3056 396 110 252 69 33 1 0 0 0 0 0 0 0 0 0 0 0 4B Combined 3/8/07 2896 348 1 4 9 10 0 1 0 0 0 0 0 0 0 0 0 0 1C Combined 3/8/07 477 198 1 1 12 13 0 1 0 0 0 0 0 0 0 0 0 0 2C Combined 3/8/07 2332 182 1 2 119 4 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 3/8/07 2700 194 0 0 97 1 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 3/8/07 4748 283 0 0 2 3 0 0 0 0 0 0 0 0 0 0 0 0 1D Combined 3/8/07 956 297 6 0 16 7 2 0 0 0 0 0 0 0 0 0 0 0 2D Combined 3/8/07 937 163 0 0 70 2 0 0 0 0 0 0 0 0 0 0 0 0

3D Combined 3/8/07 3664 277 5 1 108 17 0 0 0 0 0 0 0 0 0 0 0 0 1

91 4D Combined 3/8/07 1928 199 0 0 4 3 0 0 0 0 0 0 0 0 0 0 0 0 1E Surface 3/8/07 1248 266 0 3 9 1 1 1 0 0 0 0 0 0 0 0 0 0 1E Bottom 3/8/07 3268 210 174 25 31 207 5 0 0 0 0 0 0 0 0 0 0 0 2E Surface 3/8/07 620 196 1 0 42 3 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 3/8/07 2233 262 33 17 91 21 1 0 0 0 0 0 0 0 0 0 0 0 3E Surface 3/8/07 490 204 0 0 40 0 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 3/8/07 2012 197 2 0 38 2 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 3/8/07 471 365 4 0 17 30 2 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 3/8/07 2596 325 11 11 33 65 1 0 0 0 0 0 0 0 0 0 0 0 1F Surface 3/8/07 347 388 3 1 4 14 0 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 3/8/07 314 379 60 150 7 56 25 3 0 0 2 2 0 0 0 0 0 0 2F Surface 3/8/07 1376 442 1 0 14 6 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 3/8/07 1700 229 0 1 48 3 0 0 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

3F Surface 3/8/07 698 283 0 0 44 2 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 3/8/07 1976 250 1 0 44 3 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 3/8/07 378 245 1 0 7 12 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 3/8/07 824 234 4 7 17 16 0 1 0 0 0 0 0 0 0 0 0 0 2G Surface 3/8/07 184 672 0 0 10 8 0 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 3/8/07 1876 292 2 1 53 10 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 3/8/07 984 357 0 0 42 10 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 3/8/07 1840 250 0 1 40 11 0 0 0 0 0 0 0 0 0 0 0 0 1A Combined 3/22/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 3/22/07 2032 197 1 1 227 0 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 3/22/07 1956 112 1 1 64 0 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 3/22/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

1B Combined 3/22/07 1162 64 1 0 28 1 0 0 0 0 0 0 0 0 0 0 0 0 1

92 2B Combined 3/22/07 4284 148 2 0 173 0 1 0 0 0 0 0 0 0 0 0 0 0

3B Combined 3/22/07 6516 106 30 83 73 99 4 1 0 0 0 0 0 0 0 0 0 0 4B Combined 3/22/07 3328 66 19 11 7 17 16 0 0 0 0 0 1 0 0 0 0 0 1C Combined 3/22/07 3864 80 2 2 22 3 10 1 0 0 1 0 0 0 0 0 0 0 2C Combined 3/22/07 7516 159 0 0 71 1 1 0 0 0 0 0 0 0 0 0 0 0 3C Combined 3/22/07 7032 123 0 11 80 0 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 3/22/07 3784 95 5 0 6 7 3 0 0 0 0 0 0 0 0 0 0 0 1D Combined 3/22/07 3012 79 3 0 10 3 1 0 0 0 0 0 0 0 0 0 0 0 2D Combined 3/22/07 6248 174 1 0 75 0 1 0 0 0 0 0 0 0 0 0 0 0 3D Combined 3/22/07 6412 180 7 1 197 0 2 0 0 0 0 0 0 0 0 0 0 0 4D Combined 3/22/07 3068 79 27 1 11 60 8 0 0 0 0 0 0 0 0 0 0 0 1E Surface 3/22/07 3832 84 1 0 17 4 0 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 3/22/07 5092 124 2 3 32 2 0 0 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

2E Surface 3/22/07 2712 101 1 0 72 0 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 3/22/07 13732 279 12 1 251 1 1 0 0 0 0 0 0 0 0 0 0 0 3E Surface 3/22/07 4556 133 0 0 76 1 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 3/22/07 9940 156 1 1 59 0 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 3/22/07 2908 97 3 0 7 11 1 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 3/22/07 16516 93 61 8 20 14 7 1 0 0 0 0 0 0 0 0 0 0 1F Surface 3/22/07 4292 74 6 0 13 12 14 1 0 1 0 0 0 0 0 0 0 0 1F Bottom 3/22/07 466 73 11 4 13 9 1 0 0 0 0 0 0 0 0 0 0 0 2F Surface 3/22/07 2936 110 1 0 48 2 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 3/22/07 3920 98 0 0 94 2 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 3/22/07 8636 120 0 0 29 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 3/22/07 20768 120 4 11 101 10 0 1 0 0 1 0 0 0 0 0 0 0

4F Surface 3/22/07 15744 134 4 2 0 17 2 0 0 0 0 0 0 0 0 0 0 0 1

93 4F Bottom 3/22/07 43204 140 35 8 18 48 10 0 0 0 0 0 0 0 0 0 0 0

2G Surface 3/22/07 980 108 13 0 16 12 1 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 3/22/07 5088 75 9 3 9 27 2 0 0 0 0 0 0 0 0 0 0 0 3G Surface 3/22/07 5400 94 14 0 9 25 1 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 3/22/07 16624 85 24 5 20 51 2 0 0 0 0 0 0 0 0 0 0 0 1A Combined 4/6/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 4/6/07 710 97 9 9 24 2 0 1 0 0 0 0 0 0 0 0 0 0 3A Combined 4/6/07 302 58 6 0 30 4 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 4/6/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 4/6/07 599 31 13 3 1 9 8 0 0 0 0 0 0 0 0 0 0 0 2B Combined 4/6/07 260 52 8 0 33 3 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 4/6/07 421 64 11 47 46 79 1 0 0 0 0 0 0 0 0 0 0 0 4B Combined 4/6/07 5008 42 12 228 1 77 22 0 0 0 0 0 0 1 0 0 0 0

Table D.2. (Continued.)

1C Combined 4/6/07 439 31 21 3 0 42 9 0 0 0 0 0 0 0 0 0 0 0 2C Combined 4/6/07 170 18 0 0 3 0 0 0 0 1 0 0 0 0 0 0 0 0 3C Combined 4/6/07 756 106 8 14 67 8 1 0 0 0 0 0 0 0 0 0 0 0 4C Combined 4/6/07 2354 93 153 118 0 155 80 6 0 0 2 0 1 1 0 0 0 0 1D Combined 4/6/07 260 26 3 0 0 6 2 0 0 1 0 0 0 0 0 0 0 0 2D Combined 4/6/07 220 43 2 0 47 0 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 4/6/07 518 24 1 1 19 4 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 4/6/07 844 19 18 78 0 43 7 0 0 0 1 0 0 0 0 0 0 0 1E Surface 4/6/07 76 12 32 16 0 49 21 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 4/6/07 454 40 53 43 1 72 13 2 0 0 0 0 0 0 0 0 0 0 2E Surface 4/6/07 253 42 0 1 7 2 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 4/6/07 381 63 2 0 20 4 2 0 0 0 0 0 0 0 0 0 0 0 3E Surface 4/6/07 120 33 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0

194 3E Bottom 4/6/07 523 52 11 0 58 2 1 0 0 0 0 0 0 0 0 0 0 0

4E Surface 4/6/07 160 33 54 13 2 123 29 5 0 0 0 0 0 0 0 1 0 0 4E Bottom 4/6/07 2860 68 146 101 17 153 47 2 0 0 0 1 0 0 0 0 0 0 1F Surface 4/6/07 104 15 8 0 1 8 2 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 4/6/07 157 54 68 51 6 64 1 0 0 0 0 0 0 0 0 0 0 0 2F Surface 4/6/07 259 17 4 0 5 5 1 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 4/6/07 458 90 19 5 28 29 1 0 0 0 0 0 0 0 0 0 0 0 3F Surface 4/6/07 81 13 1 2 2 1 1 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 4/6/07 369 144 38 16 49 48 7 0 0 0 0 0 0 0 0 0 0 0 4F Surface 4/6/07 205 20 10 3 0 9 1 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 4/6/07 623 61 13 10 19 16 0 0 0 0 0 0 0 0 0 0 0 0 2G Surface 4/6/07 156 23 8 0 0 3 1 1 0 0 0 0 0 0 0 0 0 0 2G Bottom 4/6/07 253 112 23 8 11 23 1 2 0 0 0 0 0 0 0 0 0 0

Table D.2. (Continued.)

3G Surface 4/6/07 119 20 12 1 1 11 3 1 0 0 0 0 0 0 0 0 0 0 3G Bottom 4/6/07 347 46 15 6 6 23 7 0 0 0 0 0 0 0 0 0 0 0 1A Combined 5/3/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 5/3/07 379 101 0 6 14 1 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 5/3/07 652 85 6 121 19 12 5 0 0 0 0 0 0 0 0 0 0 4A Combined 5/3/07 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 5/3/07 309 14 2 4 2 0 1 1 0 0 0 0 0 0 0 0 0 0 2B Combined 5/3/07 577 165 4 7 18 1 2 1 0 0 0 0 0 0 0 0 0 0 3B Combined 5/3/07 613 109 1 5 14 0 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 5/3/07 769 10 1 22 0 12 2 5 0 0 2 0 0 0 0 0 0 0 1C Combined 5/3/07 270 105 1 4 3 1 0 1 0 0 0 0 0 0 0 0 0 0 2C Combined 5/3/07 902 136 33 80 57 22 1 1 0 0 0 0 0 0 0 0 0 0 3C Combined 5/3/07 1330 125 10 104 44 17 4 0 0 0 0 0 0 0 0 0 0 0

195 4C Combined 5/3/07 277 12 3 33 2 1 3 4 0 0 0 0 0 0 0 0 0 0

1D Combined 5/3/07 1100 30 23 18 1 14 4 1 0 0 1 1 0 0 0 1 0 0 2D Combined 5/3/07 797 134 7 5 18 0 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 5/3/07 549 47 2 4 9 1 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 5/3/07 418 13 1 28 1 6 4 6 0 0 0 0 0 0 0 0 0 0 1E Surface 5/3/07 361 19 2 1 0 4 2 1 0 0 0 0 0 0 0 0 0 0 1E Bottom 5/3/07 585 29 18 21 7 12 0 3 0 0 0 0 0 0 0 0 0 0 2E Surface 5/3/07 932 132 0 4 5 1 1 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 5/3/07 684 157 45 8 61 4 1 0 0 0 0 0 0 0 0 0 0 0 3E Surface 5/3/07 365 38 0 3 6 0 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 5/3/07 828 154 6 6 47 1 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 5/3/07 2162 18 12 12 0 10 0 4 0 0 0 0 0 0 0 0 0 0 4E Bottom 5/3/07 778 59 39 42 14 28 43 3 0 0 2 0 0 0 1 0 0 0

Table D.2. (Continued.)

1F Surface 5/3/07 529 22 4 2 0 5 0 1 0 0 0 0 0 0 0 0 0 0 1F Bottom 5/3/07 1297 57 10 9 2 10 1 0 0 0 0 0 0 0 0 0 0 0 2F Surface 5/3/07 2456 108 1 3 7 2 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 5/3/07 528 165 12 3 67 1 2 0 0 0 0 0 0 0 0 0 0 0 3F Surface 5/3/07 752 60 3 3 1 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 5/3/07 293 154 8 5 36 2 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 5/3/07 504 23 3 15 0 4 0 4 0 0 0 0 0 0 0 0 0 0 4F Bottom 5/3/07 1050 79 7 37 4 14 4 2 0 0 0 0 0 0 0 0 0 0 2G Surface 5/3/07 904 44 2 1 3 5 0 1 0 0 1 0 0 0 0 0 0 0 2G Bottom 5/3/07 107 25 4 9 3 9 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 5/3/07 1282 57 2 1 5 1 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 5/3/07 623 86 5 1 10 0 0 0 0 0 0 0 0 0 0 0 0 0

196

Table D.3. MC Spring aquatic invertebrate data for 2008 (number/L).

Calanoids Cyclopids

Transect Depth Date Nauplii

Rotifera Cladocera Ostracods Chironomids Water mites Ephemeroptera Hemiptera Nematoda Odonata larva Oligochaeta Collembola Plecoptera Amphipods Trichoptera Oligochaete Thysanoptera H Surface 1/25/08 268 4 4 2 0 2 0 0 0 0 0 0 0 0 0 0 0 3 0 H Bottom 1/25/08 55 12 15 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 H Surface 2/20/08 564 4 2 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 H Bottom 2/20/08 392 33 37 0 1 11 0 1 0 0 1 0 0 0 0 0 0 9 0 H Surface 3/18/08 529 66 10 0 0 11 0 1 0 0 5 0 0 0 0 0 0 3 0 H Bottom 3/18/08 140 50 9 0 0 8 3 0 0 0 1 0 0 0 0 0 0 1 0 H Surface 4/19/08 674 0 7 0 0 6 1 0 0 0 0 0 0 0 0 0 0 1 0 H Bottom 4/19/08 765 17 85 2 0 91 2 5 0 0 4 0 0 0 0 0 0 23 0

H Surface 5/10/08 820 10 55 0 0 15 1 1 0 5 0 0 0 0 0 0 0 0 1 197

H Bottom 5/10/08 930 11 29 0 0 8 1 0 0 1 0 0 0 0 0 0 0 0 0

I Surface 1/25/08 59 1 2 6 0 1 0 2 0 0 0 0 0 0 0 0 0 2 0 I Bottom 1/25/08 194 1 3 0 0 2 0 1 0 0 0 0 0 0 1 0 0 0 0 I Surface 2/20/08 441 3 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I Bottom 2/20/08 408 6 2 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 I Surface 3/18/08 114 33 5 0 0 9 0 2 0 0 0 0 0 0 0 0 0 0 0 I Bottom 3/18/08 237 11 2 1 0 3 0 0 0 0 1 0 0 0 0 0 0 1 0 I Surface 4/19/08 316 2 18 0 0 15 0 1 0 0 0 0 0 0 0 0 0 0 0 I Bottom 4/19/08 4833 8 6 0 0 11 1 3 0 1 0 0 0 0 0 0 0 0 1 I Surface 5/10/08 646 0 7 0 0 4 1 0 0 0 0 0 0 0 0 0 0 0 0 I Bottom 5/10/08 617 9 23 0 0 16 0 0 0 0 1 0 0 0 2 0 1 0 0

Table D.3. (Continued.)

J Surface 1/25/08 256 6 14 1 0 1 2 1 0 1 0 0 0 0 1 0 0 1 0 J Bottom 1/25/08 187 18 8 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 J Surface 2/20/08 787 73 9 0 0 4 0 2 0 0 3 0 0 0 0 0 0 1 0 J Bottom 2/20/08 542 14 7 0 0 2 0 0 0 0 3 0 0 0 0 0 0 0 0 J Surface 3/18/08 588 86 12 1 0 8 0 0 0 0 2 0 0 0 0 0 0 2 0 J Bottom 3/18/08 260 58 27 2 0 15 2 0 0 0 3 0 0 0 0 0 0 2 1 J Surface 4/19/08 235 37 79 0 1 26 0 1 0 0 0 0 0 0 0 0 0 2 2 J Bottom 4/19/08 392 25 68 0 0 41 1 1 0 0 0 0 0 0 0 0 0 9 1 J Surface 5/10/08 254 19 111 0 0 24 2 1 7 13 0 0 0 0 0 0 0 0 1 J Bottom 5/10/08 511 46 177 0 0 67 2 0 0 0 0 0 0 0 0 0 0 6 0 K Surface 1/25/08 364 36 11 3 1 11 0 0 0 0 2 0 0 0 0 0 0 2 0 K Bottom 1/25/08 137 36 27 6 0 11 0 0 0 0 0 0 0 0 1 0 0 4 0

K Surface 2/20/08 266 28 11 0 0 6 0 0 0 0 4 0 0 0 0 0 0 10 0 198 K Bottom 2/20/08 302 19 6 0 0 1 0 0 0 0 3 0 0 0 0 0 0 2 0

K Surface 3/18/08 434 176 26 4 7 25 0 2 0 0 4 0 0 0 1 0 0 5 0 K Bottom 3/18/08 131 53 15 2 0 12 0 0 0 0 0 0 0 0 0 0 0 5 0 K Surface 4/19/08 359 3 127 0 0 12 0 1 0 0 1 0 0 0 1 0 0 1 0 K Bottom 4/19/08 271 18 62 0 0 45 3 0 0 0 1 0 0 0 1 0 0 13 0 K Surface 5/10/08 346 13 56 0 0 7 0 0 0 1 0 0 0 0 2 0 0 1 0 K Bottom 5/10/08 497 33 153 0 0 54 0 1 0 0 0 0 0 0 0 0 0 11 0

Table D.4. Lake Tuendae aquatic invertebrate data for 2008 (number/L).

larva

Calanoids Cyclopids

Transect Depth Date Nauplii

Rotifera Cladocera Ostracods Chironomids Water mites Ephemeroptera Hemiptera Nematoda Odonata Oligochaeta Collembola Plecoptera Amphipods Trichoptera Oligochaete 1A Combined 1/25/08 550 13 4 0 0 25 2 0 0 0 0 0 0 0 0 0 0 0 2A Combined 1/25/08 617 16 0 0 6 1 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 1/25/08 748 14 0 0 3 1 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 1/25/08 1429 22 0 1 1 2 2 0 0 0 0 0 0 0 0 0 0 0 1B Combined 1/25/08 736 20 0 2 9 9 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 1/25/08 153 10 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 1/25/08 4722 22 0 0 5 1 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 1/25/08 1008 14 0 2 5 5 3 0 0 0 0 0 0 0 0 0 0 0

199 1C Combined 1/25/08 4202 43 0 14 7 0 0 0 0 0 0 0 0 0 0 0 0 0

2C Combined 1/25/08 522 5 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 1/25/08 2234 21 0 0 11 13 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 1/25/08 1205 18 0 0 2 6 0 0 0 0 0 0 0 0 0 0 0 0 1D Combined 1/25/08 1834 11 1 2 5 2 1 0 0 0 0 0 0 0 0 0 0 0 2D Combined 1/25/08 5216 35 0 0 6 2 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 1/25/08 6776 8 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 1/25/08 1541 20 0 3 1 5 0 0 0 0 0 0 0 0 0 0 0 0 1E Surface 1/25/08 2322 18 1 0 3 8 0 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 1/25/08 2344 22 0 0 5 4 0 0 0 0 0 0 0 0 0 0 0 0 2E Surface 1/25/08 2574 28 1 0 10 1 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 1/25/08 1707 24 0 0 6 1 0 0 0 0 0 0 0 0 0 0 0 0 3E Surface 1/25/08 761 9 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 1/25/08 1492 21 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 1/25/08 1458 20 0 0 2 5 0 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 1/25/08 1850 23 0 0 6 10 2 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

1F Surface 1/25/08 634 7 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 1/25/08 2813 20 0 0 17 24 0 0 0 0 0 0 0 0 0 0 0 0 2F Surface 1/25/08 2665 20 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 1/25/08 3120 26 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 1/25/08 1277 22 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 1/25/08 1216 19 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 1/25/08 56 2 0 0 3 1 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 1/25/08 234 35 0 1 7 2 0 0 0 0 0 0 0 0 0 0 0 0 2G Surface 1/25/08 1772 25 0 0 2 1 0 1 0 0 0 0 0 0 0 0 0 0 2G Bottom 1/25/08 2242 29 0 0 10 0 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 1/25/08 213 21 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 1/25/08 1069 15 0 0 7 9 0 0 0 0 0 0 0 0 0 0 0 0 1A Combined 2/20/08 242 10 0 1 3 14 1 0 0 0 0 0 0 0 0 0 0 0 200 2A Combined 2/20/08 796 52 0 0 11 1 0 0 0 0 0 0 0 0 0 0 0 0

3A Combined 2/20/08 656 105 1 0 9 1 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 2/20/08 1229 46 1 0 4 6 0 1 0 0 0 0 0 0 0 0 0 0 1B Combined 2/20/08 218 30 0 0 8 16 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 2/20/08 908 66 0 0 3 1 0 3 0 0 0 0 0 0 0 0 0 0 3B Combined 2/20/08 1249 57 1 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 2/20/08 1131 22 2 1 1 9 0 0 0 0 0 0 0 0 0 0 0 0 1C Combined 2/20/08 1421 39 0 0 4 13 0 0 0 0 0 0 0 0 0 0 0 0 2C Combined 2/20/08 307 16 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 2/20/08 2009 63 0 0 3 4 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 2/20/08 1048 21 1 0 2 3 0 0 0 0 0 0 0 0 0 0 0 0 1D Combined 2/20/08 1972 50 0 0 10 11 0 0 0 0 0 0 0 0 0 0 0 0 2D Combined 2/20/08 845 30 0 0 3 3 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 2/20/08 1682 22 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 2/20/08 630 67 0 4 3 2 1 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

1E Surface 2/20/08 1401 90 0 1 8 3 0 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 2/20/08 480 48 0 0 8 3 0 0 0 0 0 0 0 0 0 0 0 0 2E Surface 2/20/08 475 22 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 2/20/08 1385 67 0 0 12 2 0 0 0 0 0 0 0 0 0 0 0 0 3E Surface 2/20/08 968 59 0 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 2/20/08 1634 72 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 4E Surface 2/20/08 467 25 0 0 3 2 0 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 2/20/08 465 16 5 0 4 18 0 0 0 0 0 0 0 0 0 0 0 0 1F Surface 2/20/08 262 12 0 0 0 8 0 1 0 0 0 0 0 0 0 0 0 0 1F Bottom 2/20/08 837 33 4 0 0 39 0 0 0 0 0 0 0 0 0 0 0 0 2F Surface 2/20/08 1797 66 0 0 3 4 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 2/20/08 3714 55 0 0 13 2 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 2/20/08 797 66 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 201 3F Bottom 2/20/08 1566 38 0 0 10 1 0 0 0 0 0 0 0 0 0 0 0 0

4F Surface 2/20/08 1203 59 1 0 5 2 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 2/20/08 1600 46 0 0 3 3 0 0 0 0 0 0 0 0 0 0 0 0 2G Surface 2/20/08 628 19 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 2/20/08 2960 35 0 0 11 0 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 2/20/08 1225 34 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 2/20/08 1306 29 1 0 1 4 0 0 0 0 0 0 0 0 0 0 0 0 1A Combined 3/18/08 3159 5 2 3 0 14 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 3/18/08 844 2 1 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 3/18/08 661 1 0 1 0 3 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 3/18/08 811 3 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1B Combined 3/18/08 1474 11 0 3 2 146 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 3/18/08 499 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 3/18/08 4808 6 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 3/18/08 13948 1 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

1C Combined 3/18/08 3656 4 1 0 0 8 0 1 0 0 0 0 0 0 0 0 0 0 2C Combined 3/18/08 585 6 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 3/18/08 9914 8 1 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 3/18/08 29044 2 0 0 3 2 0 2 0 0 0 0 0 0 0 0 0 0 1D Combined 3/18/08 6350 2 2 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 2D Combined 3/18/08 15268 6 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 3/18/08 2880 14 1 0 4 1 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 3/18/08 4473 6 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1E Surface 3/18/08 1185 12 0 0 0 10 0 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 3/18/08 4968 8 0 0 4 12 0 0 0 0 0 0 0 0 0 0 0 0 2E Surface 3/18/08 1294 4 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 3/18/08 8028 17 0 0 3 3 0 0 0 0 0 0 0 0 0 0 0 0 3E Surface 3/18/08 884 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 202 3E Bottom 3/18/08 20316 20 0 0 3 1 0 0 0 0 0 0 0 0 0 0 0 0

4E Surface 3/18/08 757 10 0 0 0 16 0 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 3/18/08 2107 8 1 0 3 6 0 0 0 0 0 0 0 0 0 0 0 0 1F Surface 3/18/08 1761 6 0 0 0 15 0 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 3/18/08 4418 15 3 1 0 72 0 0 0 0 0 0 0 0 0 0 0 0 2F Surface 3/18/08 1608 2 0 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 3/18/08 12920 26 0 0 12 2 0 0 0 0 0 0 0 0 0 0 0 0 3F Surface 3/18/08 1037 12 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 3/18/08 4489 25 0 0 3 1 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 3/18/08 1901 9 0 0 0 12 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 3/18/08 56576 11 1 0 5 10 0 0 0 0 0 0 0 0 0 0 0 0 2G Surface 3/18/08 834 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 3/18/08 7084 9 0 1 5 6 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 3/18/08 737 1 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 3/18/08 9280 15 0 1 3 6 0 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

1A Combined 4/19/08 3432 6 0 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0 2A Combined 4/19/08 394 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 4/19/08 1053 7 1 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 4/19/08 4352 6 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1B Combined 4/19/08 9892 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2B Combined 4/19/08 420 5 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3B Combined 4/19/08 2880 7 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 4/19/08 2016 1 2 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1C Combined 4/19/08 7802 7 2 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 2C Combined 4/19/08 1646 3 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 4/19/08 2766 7 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 4C Combined 4/19/08 2974 1 0 2 1 1 0 0 0 0 0 0 0 0 0 0 0 0

1D Combined 4/19/08 2605 6 1 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 203 2D Combined 4/19/08 5448 3 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 3D Combined 4/19/08 3352 1 1 0 2 0 0 0 0 0 1 0 0 0 0 0 0 0 4D Combined 4/19/08 2390 4 1 1 0 5 1 0 0 0 0 0 0 0 0 0 0 0 1E Surface 4/19/08 6820 15 0 0 3 1 1 0 0 0 0 0 0 0 0 0 0 0 1E Bottom 4/19/08 4482 4 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 2E Surface 4/19/08 1990 10 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 4/19/08 5874 17 0 0 12 1 0 0 0 0 0 0 0 0 0 0 0 0 3E Surface 4/19/08 2222 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 4/19/08 8336 12 0 0 2 0 1 0 0 0 0 0 0 0 0 0 0 0 4E Surface 4/19/08 1809 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 4/19/08 4610 9 3 1 1 5 0 1 0 0 0 0 0 0 0 0 0 0 1F Surface 4/19/08 6510 21 0 0 0 4 1 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 4/19/08 3548 16 4 2 4 7 0 0 0 0 0 0 0 0 0 0 0 0 2F Surface 4/19/08 1430 10 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 4/19/08 3140 20 0 0 7 0 0 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

3F Surface 4/19/08 1147 0 1 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 4/19/08 5200 20 0 0 2 0 1 0 0 0 0 0 0 0 0 0 0 0 4F Surface 4/19/08 2172 7 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 4F Bottom 4/19/08 4230 4 9 5 1 13 0 0 0 0 0 0 0 0 0 0 0 0 2G Surface 4/19/08 2541 13 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 2G Bottom 4/19/08 3670 15 0 0 5 1 1 0 0 0 0 0 0 0 0 0 0 0 3G Surface 4/19/08 2834 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3G Bottom 4/19/08 3007 8 0 0 4 2 0 0 0 0 0 0 0 0 0 0 0 0 1A Combined 5/10/08 516 2 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 2A Combined 5/10/08 960 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3A Combined 5/10/08 1861 7 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 4A Combined 5/10/08 881 6 0 0 0 2 0 1 0 0 0 0 0 0 0 0 0 0 1B Combined 5/10/08 628 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 204 2B Combined 5/10/08 927 4 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0

3B Combined 5/10/08 1064 2 0 1 1 2 0 0 0 0 0 0 0 0 0 0 0 0 4B Combined 5/10/08 1644 14 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1C Combined 5/10/08 1300 4 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 2C Combined 5/10/08 993 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3C Combined 5/10/08 1731 6 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 4C Combined 5/10/08 2333 25 0 2 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1D Combined 5/10/08 1026 3 0 0 0 6 0 0 0 0 0 0 0 0 0 0 0 0 2D Combined 5/10/08 1732 7 0 0 0 1 2 0 0 0 0 0 0 0 0 0 0 0 3D Combined 5/10/08 1764 9 0 0 3 7 0 0 0 0 0 0 0 0 0 0 0 0 4D Combined 5/10/08 1340 17 0 0 0 2 0 0 0 1 1 0 0 0 0 0 0 0 1E Surface 5/10/08 949 1 4 0 0 7 0 0 0 0 1 0 0 0 0 0 0 0 1E Bottom 5/10/08 2382 18 0 0 4 3 0 0 1 0 0 0 0 0 0 0 0 0 2E Surface 5/10/08 1080 1 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 2E Bottom 5/10/08 1490 20 0 0 2 6 0 0 0 0 0 0 0 0 0 0 0 0

Table D.4. (Continued.)

3E Surface 5/10/08 1173 1 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 3E Bottom 5/10/08 1314 14 1 0 2 2 1 0 0 0 0 0 0 0 0 0 0 0 4E Surface 5/10/08 1052 2 1 0 0 11 0 0 0 0 0 0 0 0 0 0 0 0 4E Bottom 5/10/08 1654 6 0 0 0 10 0 0 0 0 0 0 0 0 0 0 0 0 1F Surface 5/10/08 484 1 0 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 1F Bottom 5/10/08 1300 2 1 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 2F Surface 5/10/08 768 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2F Bottom 5/10/08 1210 11 0 0 1 2 1 0 0 1 0 0 0 0 0 0 0 0 3F Surface 5/10/08 1584 8 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3F Bottom 5/10/08 1630 6 0 0 9 5 0 0 0 0 0 0 0 0 0 0 0 0 4F Surface 5/10/08 1533 7 2 0 0 3 0 0 0 0 1 0 0 0 0 0 0 0 4F Bottom 5/10/08 1934 2 0 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0

2G Surface 5/10/08 920 0 6 0 0 15 1 1 0 0 0 0 0 0 0 0 0 0 205 2G Bottom 5/10/08 802 7 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 3G Surface 5/10/08 831 1 0 0 0 4 0 2 0 0 0 0 0 0 0 0 0 0 3G Bottom 5/10/08 1421 5 1 0 2 4 0 0 0 0 0 0 0 0 0 0 0 0

Table D.5. MC Spring aquatic invertebrate data for 2009 (number/L).

Transect Depth Date

Rotifera Nauplii Cladocera Ostracods Calanoids Cyclopids Chironomids Water mites Ephemeroptera Hemiptera Nematoda Odonata larva Oligochaeta Collembola Plecoptera Amphipods Trichoptera Unknown H Surface 3/28/09 329 4 9 1 0 4 0 0 0 0 0 0 0 0 0 0 0 0 H Bottom 3/28/09 354 1 3 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 H Surface 4/18/09 195 1 1 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 H Bottom 4/18/09 264 2 3 1 1 4 0 0 0 0 0 0 0 0 0 0 0 0 H Surface 5/13/09 222 5 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 H Bottom 5/13/09 144 0 2 1 2 1 0 0 0 0 0 0 0 0 0 0 0 0 I Surface 3/28/09 269 1 4 2 0 4 0 0 0 0 0 0 0 0 0 0 0 0 I Bottom 3/28/09 349 2 1 4 1 2 1 0 0 0 0 0 0 0 0 0 0 0 206 I Surface 4/18/09 304 1 0 4 1 5 0 0 0 0 0 0 0 0 0 0 0 0

I Bottom 4/18/09 177 1 0 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 I Surface 5/13/09 203 2 0 2 0 6 0 0 0 0 0 0 0 0 0 0 0 0 I Bottom 5/13/09 232 4 0 1 0 5 0 0 0 0 0 0 0 0 0 0 0 0 J Surface 3/28/09 272 1 1 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 J Bottom 3/28/09 70 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 J Surface 4/18/09 229 2 1 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 J Bottom 4/18/09 207 1 0 1 1 2 0 0 0 0 0 0 0 0 0 0 0 0 J Surface 5/13/09 270 2 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 0 J Bottom 5/13/09 205 4 0 0 5 3 0 0 0 0 0 0 0 0 0 0 0 0 K Surface 3/28/09 169 1 0 2 0 2 0 0 0 0 0 0 0 0 0 0 0 0 K Bottom 3/28/09 263 1 0 3 0 2 1 0 0 0 0 0 0 0 0 0 0 0 K Surface 4/18/09 171 0 2 1 4 3 0 0 0 0 0 0 0 0 0 0 0 0 K Bottom 4/18/09 156 2 1 1 0 4 0 0 0 0 0 0 0 0 0 0 0 0 K Surface 5/13/09 321 0 15 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 K Bottom 5/13/09 101 2 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0

Table D.6. Lake Tuendae aquatic invertebrate data for 2009 (number/L).

Transect Depth Date

Rotifera Nauplii Cladocera Ostracods Calanoids Cyclopids Chironomids Water mites Ephemeroptera Hemiptera Nematoda Odonata larva Oligochaeta Collembola Plecoptera Amphipods Trichoptera Unknown 1A Surface 3/28/09 10320 43 3 1 1 1 0 14 0 0 0 0 0 0 0 0 0 0 1A Bottom 3/28/09 6612 28 1 0 2 3 0 7 0 0 0 0 0 0 0 0 0 0 2A Surface 3/28/09 6173 29 1 1 3 5 0 8 0 0 0 0 0 0 0 0 0 0 2A Bottom 3/28/09 6324 73 0 0 1 4 0 8 0 0 0 0 0 0 0 0 0 0 3A Surface 3/28/09 3268 30 0 0 2 0 0 5 0 0 0 0 0 0 0 0 0 0 3A Bottom 3/28/09 4558 45 0 0 0 3 0 2 0 0 0 0 0 0 0 0 0 0 4A Surface 3/28/09 3723 17 0 0 1 3 0 7 0 0 0 0 0 0 0 0 0 0

4A Bottom 3/28/09 3700 14 2 0 0 3 0 7 0 0 0 0 0 0 0 0 0 0 207 1B Surface 3/28/09 5874 23 0 0 1 2 0 13 0 0 0 0 0 0 0 0 0 0 1B Bottom 3/28/09 5273 31 0 0 0 4 0 9 0 0 0 0 0 0 0 0 0 0 2B Surface 3/28/09 8552 33 0 0 1 1 0 15 0 0 0 0 0 0 0 0 0 0 2B Bottom 3/28/09 9094 22 0 0 0 0 0 15 0 0 0 0 0 0 0 0 0 0 3B Surface 3/28/09 6773 18 0 0 1 3 0 7 0 0 0 0 0 0 0 0 0 0 3B Bottom 3/28/09 6635 18 0 1 1 3 0 2 0 0 0 0 0 0 0 0 0 0 4B Surface 3/28/09 3219 26 0 0 5 2 0 4 0 0 0 0 0 0 0 0 0 0 4B Bottom 3/28/09 3530 30 0 0 0 2 0 3 0 0 0 0 0 0 0 0 0 0 1C Surface 3/28/09 5591 30 0 0 0 2 0 9 0 0 0 0 0 0 0 0 0 0 1C Bottom 3/28/09 4270 10 0 0 0 3 0 7 0 0 0 0 0 0 0 0 0 0 2C Surface 3/28/09 1897 24 0 0 0 4 0 10 0 0 0 0 0 0 0 0 0 0 2C Bottom 3/28/09 3271 30 0 1 1 0 0 10 0 0 0 0 0 0 0 0 0 0 3C Surface 3/28/09 3594 14 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 3C Bottom 3/28/09 3384 33 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 4C Surface 3/28/09 6842 19 0 0 0 1 0 6 0 0 0 0 0 0 0 0 0 0 4C Bottom 3/28/09 5851 10 0 0 0 1 0 11 0 0 0 0 0 0 0 0 0 0

Table D.6. (Continued).

1D Surface 3/28/09 5668 9 0 0 1 0 0 5 0 0 0 0 0 0 0 0 0 0 1D Bottom 3/28/09 5121 18 0 0 0 2 0 3 0 0 0 0 0 0 0 0 0 0 2D Surface 3/28/09 2703 10 0 0 1 0 0 5 0 0 0 0 0 0 0 0 0 0 2D Bottom 3/28/09 3340 15 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 3D Surface 3/28/09 2584 19 0 0 0 0 0 6 0 0 0 0 0 0 0 0 0 0 3D Bottom 3/28/09 2801 9 0 0 0 1 0 5 0 0 0 0 0 0 0 0 0 0 4D Surface 3/28/09 2338 6 0 0 0 1 0 5 0 0 0 0 0 0 0 0 0 0 4D Bottom 3/28/09 3027 11 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 1E Surface 3/28/09 4256 14 0 0 1 4 0 5 0 0 0 0 0 0 0 0 0 0 1E Bottom 3/28/09 5050 10 0 1 0 2 0 8 0 0 0 0 0 0 0 0 0 0 2E Surface 3/28/09 7135 19 0 0 0 2 0 6 0 0 0 0 0 0 0 0 0 0 2E Bottom 3/28/09 6959 10 0 0 0 2 0 9 0 0 0 0 0 0 0 0 0 0

3E Surface 3/28/09 5205 18 0 0 1 1 0 12 0 0 0 0 0 0 0 0 0 0 208 3E Bottom 3/28/09 4472 8 0 0 0 1 0 9 0 0 0 0 0 0 0 0 0 0

4E Surface 3/28/09 5662 8 0 0 0 1 0 12 0 0 0 0 0 0 0 0 0 0 4E Bottom 3/28/09 2592 18 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 1F Surface 3/28/09 6692 16 0 0 1 3 0 4 0 0 0 0 0 0 0 0 0 0 1F Bottom 3/28/09 4586 13 0 1 0 1 0 8 0 0 0 0 0 0 0 0 0 0 2F Surface 3/28/09 7328 12 0 0 1 0 0 6 0 0 0 0 0 0 0 0 0 0 2F Bottom 3/28/09 8806 7 0 0 0 0 0 14 0 0 0 0 0 0 0 0 0 0 3F Surface 3/28/09 7542 11 0 0 0 2 0 9 0 0 0 0 0 0 0 0 0 0 3F Bottom 3/28/09 5885 7 0 0 0 1 0 10 0 0 0 0 0 0 0 0 0 0 4F Surface 3/28/09 4721 5 0 0 0 1 0 4 0 0 0 0 0 0 0 0 0 0 4F Bottom 3/28/09 6329 5 0 0 1 0 0 17 0 0 0 0 0 0 0 0 0 0 2G Surface 3/28/09 7269 14 0 0 2 1 0 11 0 0 0 0 0 0 0 0 0 0 2G Bottom 3/28/09 5440 11 0 0 1 2 0 11 0 0 0 0 0 0 0 0 0 0 3G Surface 3/28/09 6526 7 0 0 0 1 0 9 0 0 0 0 0 0 0 0 0 0 3G Bottom 3/28/09 3281 5 0 0 0 1 0 7 0 0 0 0 0 0 0 0 0 0

Table D.6. (Continued).

1A Surface 4/18/09 3011 4 0 1 1 2 0 5 0 0 0 0 0 0 0 0 0 0 1A Bottom 4/18/09 2034 1 0 0 0 2 0 2 0 0 0 0 0 0 0 0 0 0 2A Surface 4/18/09 2844 1 0 1 2 4 0 1 0 0 0 0 0 0 0 0 0 0 2A Bottom 4/18/09 2676 2 0 0 0 3 0 2 0 0 0 0 0 0 0 0 0 0 3A Surface 4/18/09 3628 3 0 0 3 6 0 5 0 0 0 0 0 0 0 0 0 0 3A Bottom 4/18/09 5668 6 0 0 2 5 0 6 0 0 0 0 0 0 0 0 0 0 4A Surface 4/18/09 6175 3 0 1 3 8 0 7 0 0 0 0 0 0 0 0 0 0 4A Bottom 4/18/09 4812 3 1 2 4 3 0 6 0 0 0 0 0 0 0 0 0 0 1B Surface 4/18/09 3568 1 1 2 1 7 0 8 0 0 0 0 0 0 0 0 0 0 1B Bottom 4/18/09 1631 1 1 1 2 4 0 6 0 0 0 0 0 0 0 0 0 0 2B Surface 4/18/09 3107 0 0 0 0 2 0 7 0 0 0 0 0 0 0 0 0 0 2B Bottom 4/18/09 2318 0 2 1 2 5 0 2 0 0 0 0 0 0 0 0 0 0

3B Surface 4/18/09 2567 1 2 0 0 3 0 12 0 0 0 0 0 0 0 0 0 0 209

3B Bottom 4/18/09 5189 1 4 0 0 7 0 8 0 0 0 0 0 0 0 0 0 0

4B Surface 4/18/09 3176 4 0 1 1 4 0 4 0 0 0 0 0 0 0 0 0 0 4B Bottom 4/18/09 1264 1 2 3 1 5 0 2 0 0 0 0 0 0 0 0 0 0 1C Surface 4/18/09 1887 1 0 2 1 6 0 4 0 0 0 0 0 0 0 0 0 0 1C Bottom 4/18/09 3892 2 1 3 1 7 0 3 0 0 0 0 0 0 0 0 0 0 2C Surface 4/18/09 3740 1 0 1 1 5 0 3 0 0 0 0 0 0 0 0 0 0 2C Bottom 4/18/09 3134 1 0 1 1 2 0 4 0 0 0 0 0 0 0 0 0 0 3C Surface 4/18/09 3354 9 1 12 13 3 0 6 0 0 0 0 0 0 0 0 0 0 3C Bottom 4/18/09 3427 4 1 4 0 5 1 0 0 0 0 0 0 0 0 0 0 0 4C Surface 4/18/09 3093 2 2 5 0 8 0 2 0 0 0 0 0 0 0 0 0 0 4C Bottom 4/18/09 3401 1 3 1 0 3 0 1 0 0 0 0 0 0 0 0 0 0 1D Surface 4/18/09 3364 10 6 3 3 9 0 0 0 0 0 0 0 0 0 0 0 0 1D Bottom 4/18/09 5263 3 0 6 2 9 0 3 0 0 0 0 0 0 0 0 0 0 2D Surface 4/18/09 3861 5 0 20 0 7 0 7 0 0 0 0 0 0 0 0 0 0 2D Bottom 4/18/09 2695 5 1 7 1 14 1 6 0 0 0 0 0 0 0 0 0 0

Table D.6. (Continued).

3D Surface 4/18/09 3675 9 0 0 3 11 0 4 0 0 0 0 0 0 0 0 0 0 3D Bottom 4/18/09 5955 12 1 5 4 14 1 19 0 0 0 0 0 0 0 0 0 0 4D Surface 4/18/09 5854 14 3 9 10 17 0 16 0 0 0 0 0 0 0 0 0 0 4D Bottom 4/18/09 8323 11 2 8 4 32 0 7 0 0 0 0 0 0 0 0 0 0 1E Surface 4/18/09 5661 16 2 15 3 18 0 4 0 0 0 0 0 0 0 0 0 0 1E Bottom 4/18/09 6250 12 1 23 3 24 0 8 0 0 0 0 0 0 0 0 0 0 2E Surface 4/18/09 6214 7 1 9 2 16 0 4 0 0 0 0 0 0 0 0 0 0 2E Bottom 4/18/09 4327 10 1 14 0 20 0 5 0 0 0 0 0 0 0 0 0 0 3E Surface 4/18/09 4442 7 0 16 0 16 1 6 0 0 0 0 0 0 0 0 0 0 3E Bottom 4/18/09 2843 11 6 15 6 23 1 9 0 0 0 0 0 0 0 0 0 0 4E Surface 4/18/09 6424 18 1 17 4 24 0 11 0 0 0 0 0 0 0 0 0 0 4E Bottom 4/18/09 5378 8 1 27 6 30 1 9 0 0 0 0 0 0 0 0 0 0 1F

210 Surface 4/18/09 6119 20 0 12 7 19 0 8 0 0 0 0 0 0 0 0 0 0

1F Bottom 4/18/09 4453 9 0 8 4 13 0 5 0 0 0 0 0 0 0 0 0 0

2F Surface 4/18/09 4951 20 1 28 4 22 2 15 0 0 0 0 0 0 0 0 0 0 2F Bottom 4/18/09 3076 4 1 7 2 13 0 1 0 0 0 0 0 0 0 0 0 0 3F Surface 4/18/09 501 2 0 2 3 0 1 1 0 0 0 0 0 0 0 0 0 0 3F Bottom 4/18/09 1160 4 0 3 0 2 0 1 0 0 0 0 0 0 0 0 0 0 4F Surface 4/18/09 5944 7 3 7 3 14 0 6 0 0 0 0 0 0 0 0 0 0 4F Bottom 4/18/09 4866 10 1 12 2 11 0 4 0 0 0 0 0 0 0 0 0 0 2G Surface 4/18/09 5891 19 3 25 3 25 2 6 0 0 0 0 0 0 0 0 0 0 2G Bottom 4/18/09 4988 8 1 23 3 14 0 6 0 0 0 0 0 0 0 0 0 0 3G Surface 4/18/09 6791 12 0 11 5 20 0 4 0 0 0 0 0 0 0 0 0 0 3G Bottom 4/18/09 3877 10 6 12 4 14 1 4 0 0 0 0 0 0 0 0 0 0 1A Surface 5/13/09 668 0 0 0 0 3 0 1 0 0 0 0 0 0 0 0 0 0 1A Bottom 5/13/09 359 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 2A Surface 5/13/09 1926 2 0 1 0 0 0 2 0 0 0 0 0 0 0 0 0 0 2A Bottom 5/13/09 2249 7 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0

Table D.6. (Continued).

3A Surface 5/13/09 1219 1 0 0 1 9 0 9 0 0 0 0 0 0 0 0 0 0 3A Bottom 5/13/09 2743 5 0 0 5 8 0 6 0 0 0 0 0 0 0 0 0 0 4A Surface 5/13/09 2732 2 0 2 4 5 0 11 0 0 0 0 0 0 0 0 0 0 4A Bottom 5/13/09 3131 1 0 2 1 1 0 8 0 0 0 0 0 0 0 0 0 0 1B Surface 5/13/09 2282 10 2 2 0 5 0 5 0 0 0 0 0 0 0 0 0 0 1B Bottom 5/13/09 2669 2 4 2 5 7 0 9 0 0 0 0 0 0 0 0 0 0 2B Surface 5/13/09 5100 1 0 0 2 14 0 9 0 0 0 0 0 0 0 0 0 0 2B Bottom 5/13/09 1053 5 2 2 3 5 0 5 0 0 0 0 0 0 0 0 0 0 3B Surface 5/13/09 1702 3 1 3 7 2 0 9 0 0 0 0 0 0 0 0 0 0 3B Bottom 5/13/09 3499 0 1 3 2 1 0 6 0 0 0 0 0 0 0 0 0 0 4B Surface 5/13/09 2127 2 2 5 1 3 0 8 0 0 0 0 0 0 0 0 0 0 4B Bottom 5/13/09 1129 6 2 1 2 6 0 7 0 0 0 0 0 0 0 0 0 0 1C Surface 5/13/09 1470 0 1 3 6 1 0 2 0 0 0 0 0 0 0 0 0 0 211 1C Bottom 5/13/09 2537 3 1 4 1 4 0 10 0 0 0 0 0 0 0 0 0 0

2C Surface 5/13/09 2778 2 2 15 2 3 0 9 0 0 0 0 0 0 0 0 0 0 2C Bottom 5/13/09 2804 1 6 7 5 1 0 7 0 0 0 0 0 0 0 0 0 0 3C Surface 5/13/09 415 1 3 6 7 1 0 15 0 0 0 0 0 0 0 0 0 0 3C Bottom 5/13/09 3406 3 10 1 2 0 0 5 0 0 0 0 0 0 0 0 0 0 4C Surface 5/13/09 1846 4 0 2 0 1 0 2 0 0 0 0 0 0 0 0 0 0 4C Bottom 5/13/09 2402 3 0 2 4 5 0 3 0 0 0 0 0 0 0 0 0 0 1D Surface 5/13/09 3063 3 10 3 9 1 0 17 0 0 0 0 0 0 0 0 0 0 1D Bottom 5/13/09 2441 5 3 4 0 0 0 28 0 0 0 0 0 0 0 0 0 0 2D Surface 5/13/09 2261 5 6 4 1 4 0 14 0 0 0 0 0 0 0 0 0 0 2D Bottom 5/13/09 3123 1 13 2 0 0 0 13 0 0 0 0 0 0 0 0 0 0 3D Surface 5/13/09 2362 3 8 5 2 7 0 3 0 0 0 0 0 0 0 0 0 0 3D Bottom 5/13/09 1701 13 6 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 4D Surface 5/13/09 179 1 0 2 0 1 0 19 0 0 0 0 0 0 0 0 0 0 4D Bottom 5/13/09 3192 0 0 0 4 4 0 16 0 0 0 0 0 0 0 0 0 0

Table D.6. (Continued).

1E Surface 5/13/09 2286 9 11 2 0 8 0 4 0 0 0 0 0 0 0 0 0 0 1E Bottom 5/13/09 1206 3 12 3 0 1 0 2 0 0 0 0 0 0 0 0 0 0 2E Surface 5/13/09 2687 0 4 0 1 1 0 28 0 0 0 0 0 0 0 0 0 0 2E Bottom 5/13/09 2017 8 3 3 1 1 0 3 0 0 0 0 0 0 0 0 0 0 3E Surface 5/13/09 2305 3 0 3 0 1 0 33 0 0 0 0 0 0 0 0 0 0 3E Bottom 5/13/09 927 0 0 3 0 1 0 10 0 0 0 0 0 0 0 0 0 0 4E Surface 5/13/09 2780 6 0 2 0 2 0 8 0 0 0 0 0 0 0 0 0 0 4E Bottom 5/13/09 1624 1 0 0 14 3 0 10 0 0 0 0 0 0 0 0 0 0 1F Surface 5/13/09 1225 0 13 12 2 2 0 21 0 0 0 0 0 0 0 0 0 0 1F Bottom 5/13/09 1358 0 7 1 4 0 0 17 0 0 0 0 0 0 0 0 0 0 2F Surface 5/13/09 550 7 2 34 1 1 0 6 0 0 0 0 0 0 0 0 0 0 2F Bottom 5/13/09 3689 10 2 16 0 0 0 39 0 0 0 0 0 0 0 0 0 0

3F Surface 5/13/09 4061 53 0 56 1 1 0 16 0 0 0 0 0 0 0 0 0 0 212

3F Bottom 5/13/09 2154 4 8 4 1 1 0 5 0 0 0 0 0 0 0 0 0 0

4F Surface 5/13/09 1947 18 0 1 1 4 0 3 0 0 0 0 0 0 0 0 0 0 4F Bottom 5/13/09 205 13 1 4 1 0 0 35 0 0 0 0 0 0 0 0 0 0 2G Surface 5/13/09 2664 4 20 2 1 6 0 14 0 0 0 0 0 0 0 0 0 0 2G Bottom 5/13/09 3268 0 6 0 2 0 0 54 0 0 0 0 0 0 0 0 0 0 3G Surface 5/13/09 1530 15 9 0 4 1 0 9 0 0 0 0 0 0 0 0 0 0 3G Bottom 5/13/09 312 8 5 1 1 0 0 6 0 0 0 0 0 0 0 0 0 0