7046 ‎(3)‎

• 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

ACKNOWLEDGEMEN'TS . . . . . , . . . . . . . , . , . . , , . . . . . . . . . . , . . . . . . . . . . . . . , . . .. Vll1

1.0 IN1'RODUCTION , , . , . , . . . . , . . . . . . . , . . . . , . . . . . . . . . , . . . . . . , . . . , . . . . . . . . . 1

1.1 Objectives ...,......."...".........",."..........,.,........... 1

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

20 STUDY AREA ...,........,...................,.,.........,..,........ 2

3.0 MEllIODS .........,......,...................,..........,......"... 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 RESUL 1'S ..............,.,..,.............",.,.,.",............,.,. 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

4.22 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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