7046 ‎(4)‎

• UCREFRP Catalog Number: 7046
• Author: Valdez, R. A., W. J. Masslich and A. Wasowicz.
• Title: Final Report\
• USFW Year: 1992.
• Copyright Material: NO

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TABLE OF CONTENTS

EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

ACKN"OWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. viii

1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Objectives ......................................................... 1

1.2 Background ........................................................ 1

2.0 STUDY AREA ........................................................ 2

3.0 METHODS ........................................................... 3

3.1 Sample Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.2 Sample Effort and Techniques .......................................... 3

3.3 Habitat Analysis ..................................................... 4

3.4 Water Quality, Macroinvertebrate and Sediment Sampling ..................... 5

3.5 Bioassays .......................................................... 6

4.0 RESULTS ............................................................ 6

4.1 Summary of Fish Collections. . . . . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2 Summary of Fish Collections by Gear Type with CPE Statistics . . . . . . . . . . . . . . . . . . 7

4.2.1 Electrofishing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4.2.2 Gill and Trammel Netting ......................................... 8

4.2.3 Seining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2.4 Fish Species Composition - Past and Present ........................... 9
4.3 Summary of Colorado Squawfish Habitat Assessment . . . . . . . . . . . . . . . . . . . . . . . .. 10
4.3.1 Physical Attributes .............................................. 10
4.3.2 Chemical Attributes ............................................. 15
4.3.3 Fish Tissue and Sediment Analysis .................................. 20
4.3.4 Biological Attributes ............................ . . . . . . . . . . . . . . . .. 22
4.4 Feasibility of Reintroducing Colorado SquawfIsh ............................ 23
4.4.1 Incubation of Eggs in Situ ......................................... 23

4.4.2 Release of Juveniles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 24

4.4.3 Chemoreception studies with adults .................................. 24

5.0 SUMMARY OF FINDINGS .............................................. 24

6.0 RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 25

APPENDIX A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 112

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