Estimates of Chinook salmon abundance in the Kenai River using split-beam sonar, 2002

117 Pages·2004·1.05 MB·English

Fishery Data Series No. 04-29
Estimates of Chinook Salmon Abundance in the Kenai
River Using Split-Beam Sonar, 2002

by
James D. Miller,
Debby L. Burwen,
and
Steve J. Fleischman

December 2004
Alaska Department of Fish and Game Divisions of Sport Fish and Commercial Fisheries
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Weights and measures (English) north N base of natural logarithm e
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O
ampere A trademark (cid:228) percent %
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direct current DC (adjective) U.S. probability of a type I error
hertz Hz United States of (rejection of the null
horsepower hp America (noun) USA hypothesis when true) a
hydrogen ion activity pH U.S.C. United States probability of a type II error
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(negative log of) (acceptance of the null
parts per million ppm U.S. state use two-letter hypothesis when false) b
abbreviations
parts per thousand ppt, second (angular) "
(e.g., AK, WA)
‰ standard deviation SD
volts V standard error SE
watts W variance
population Var
sample var
FISHERY DATA SERIES NO. 04-29
ESTIMATES OF CHINOOK SALMON ABUNDANCE IN THE KENAI
RIVER USING SPLIT-BEAM SONAR, 2002

by

James D. Miller,
Debby L. Burwen,
Division of Sport Fish, Anchorage
and
Steve J. Fleischman
Division of Sport Fish, Research and Technical Services, Anchorage

Alaska Department of Fish and Game
Division of Sport Fish, Research and Technical Services
333 Raspberry Road, Anchorage, Alaska 99518-1599

December 2004
This investigation was partially financed by the Federal Aid in Sport Fish Restoration Act
(16 U.S.C. 777-777K) under project F-10-18, Job No. S-2-5b.
The Division of Sport Fish Fishery Data Series was established in 1987 for the publication of technically oriented
results for a single project or group of closely related projects. Since 2004, the Division of Commercial Fisheries has
also used the Fishery Data Series. Fishery Data Series reports are intended for fishery and other technical
professionals. Fishery Data Series reports are available through the Alaska State Library and on the Internet:
http://www.sf.adfg.state.ak.us/statewide/divreports/html/intersearch.cfm This publication has undergone editorial
and peer review.
James D. Miller, Debby L. Burwen,
Alaska Department of Fish and Game, Division of Sport Fish
333 Raspberry Road, Anchorage, Alaska 99518-1599, USA
and
Steve J. Fleischman
Alaska Department of Fish and Game, Division of Sport Fish, Research and Technical Services
333 Raspberry Road, Anchorage, Alaska 99518-1599, USA

This document should be cited as:
Miller, J. D., D. L. Burwen, and S. J. Fleischman. 2004. Estimates of Chinook salmon abundance in the Kenai
River using split-beam sonar, 2002. Alaska Department of Fish and Game, Fishery Data Series No. 04-29,
Anchorage.
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If you believe you have been discriminated against in any program, activity, or facility, or if you desire further
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For information on alternative formats for this and other department publications, please contact the department
ADA Coordinator at (voice) 907-465-4120, (TDD) 907-465-3646, or (FAX) 907-465-2440.
TABLE OF CONTENTS
Page
LIST OF TABLES..........................................................................................................................................................................iii
LIST OF FIGURES........................................................................................................................................................................iv
LIST OF APPENDICES................................................................................................................................................................v
ABSTRACT ......................................................................................................................................................................................1
INTRODUCTION............................................................................................................................................................................1
Project Objectives.............................................................................................................................................................................5
METHODS........................................................................................................................................................................................5
Study Area..........................................................................................................................................................................................5
Site Description.................................................................................................................................................................................6
Acoustic Sampling............................................................................................................................................................................6
Sonar System Configuration......................................................................................................................................................6
Bottom Mapping and Beam Coverage.....................................................................................................................................8
System Calibration....................................................................................................................................................................11
Sampling Procedure..................................................................................................................................................................12
Echo Sounder Settings..............................................................................................................................................................12
Data Acquisition........................................................................................................................................................................12
Fish Tracking and Echo Counting...............................................................................................................................................14
Data Analyses..................................................................................................................................................................................15
Tidal and Temporal Distribution............................................................................................................................................15
Spatial Distribution...................................................................................................................................................................15
Target Strength Distribution....................................................................................................................................................16
Species Discrimination.............................................................................................................................................................16
Passage Estimates......................................................................................................................................................................17
RESULTS........................................................................................................................................................................................19
System Calibration.........................................................................................................................................................................19
Target Tracking...............................................................................................................................................................................20
Tidal and Temporal Distribution..................................................................................................................................................20
Spatial Distribution.........................................................................................................................................................................20
Vertical Distribution.................................................................................................................................................................20
Range Distribution....................................................................................................................................................................22
Target Strength...........................................................................................................................................................................23
Passage Estimates......................................................................................................................................................................27
DISCUSSION.................................................................................................................................................................................29
Spatial Distribution.........................................................................................................................................................................29
Bank Preference.........................................................................................................................................................................29
Vertical Distribution.................................................................................................................................................................33
Range Distribution....................................................................................................................................................................38
Target Strength................................................................................................................................................................................38
Direction of Travel.........................................................................................................................................................................39
Comparison of Passage Estimates with Other Indices.............................................................................................................40
Early Run....................................................................................................................................................................................41
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TABLE OF CONTENTS (Continued)
Page
Late Run......................................................................................................................................................................................41
Outlook.............................................................................................................................................................................................44
ACKNOWLEDGMENTS.............................................................................................................................................................45
REFERENCES CITED..................................................................................................................................................................47
APPENDIX A. TARGET STRENGTH ESTIMATION........................................................................................................53
APPENDIX B. MID RIVER SONAR COVERAGE..............................................................................................................55
APPENDIX C. SYSTEM PARAMETERS..............................................................................................................................69
APPENDIX D. DATA FLOW....................................................................................................................................................77
APPENDIX E. EXCLUDED HOURLY SAMPLES..............................................................................................................79
APPENDIX F. DAILY PROPORTIONS OF UPSTREAM AND DOWNSTREAM FISH FOR THE 2002
EARLY AND LATE KENAI RIVER CHINOOK SALMON RUNS..................................................................................81
APPENDIX G. AVERAGE VERTICAL ANGLE BY TIDE STAGE, RUN, BANK, AND FISH
ORIENTATION (UPSTREAM OR DOWNSTREAM) FOR THE 2002 KENAI RIVER CHINOOK SALMON
RUNS................................................................................................................................................................................................85
APPENDIX H. HISTORIC PASSAGE BY YEAR AND DATE (1987–2002)................................................................89
APPENDIX I. FILTERED (CONVENTIONAL), UNFILTERED, AND NET-APPORTIONED CHINOOK
PASSAGE ESTIMATES, KENAI RIVER SONAR, EARLY AND LATE RUNS, 2002...............................................95
APPENDIX J. ECHO LENGTH MIXTURE MODEL ESTIMATES OF SPECIES COMPOSITION AND
CHINOOK ABUNDANCE, EARLY RUN 2002....................................................................................................................99
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LIST OF TABLES
Table Page
1. Main components of the split-beam sonar system used in 2002..............................................................................8
2. HTI model 244 digital echo sounder settings used in 2002....................................................................................12
3. Echo acceptance criteria for digital echo processing, 2002.....................................................................................14
4. Results of 2002 in situ calibration verifications using a 38.1 mm tungsten carbide standard sphere..............20
5. Estimates of Chinook salmon passage by tide stage and direction of travel for the 2002 early run (16
May to 30 June)...............................................................................................................................................................21
6. Estimates of Chinook salmon passage by tide stage and direction of travel for the 2002 late run (1 July
to 5 August).....................................................................................................................................................................21
7. Estimates of early-run fish passage by direction of travel, 2002............................................................................31
8. Estimates of late-run fish passage by direction of travel, 2002..............................................................................31
9. Mean target strength (dB) for upstream and downstream targets by river bank (Chinook only) during
the early (16 May-30 June) and late (1 July-5 August) runs, 2002........................................................................31
10. Estimated daily upstream passage of Chinook salmon, Kenai River sonar, early run, 2002............................36
11. Estimated daily upstream passage of Chinook salmon, Kenai River sonar, late run, 2002...............................37

iii
LIST OF FIGURES
Figure Page
1. Cook Inlet showing location of the Kenai River.........................................................................................................2
2. Kenai River showing location of Chinook salmon sonar site, 2002........................................................................7
3. Cross-sectional (top) and aerial (bottom) views of sonar site showing insonified portions of the Kenai
River, 2002.........................................................................................................................................................................9
4. Daily right- and left-bank transducer locations and counting ranges relative to bipod tower located on
the right bank, Kenai River, 2002................................................................................................................................10
5. Left- and right-bank bottom profiles at the Kenai River Chinook sonar site with approximate
transducer locations and sonar beam coverage for 16 May 2002...........................................................................11
6. Schematic of 2002 split-beam sonar system configuration and data flow............................................................13
7. Distribution of upstream and downstream migrating fish by tide stage during the early (top panel) and
late (bottom panel) runs, Kenai River, 2002..............................................................................................................22
8. Vertical distributions of early-run upstream and downstream migrating fish on the left and right banks,
Kenai River, 2002...........................................................................................................................................................23
9. Vertical distributions of early-run upstream fish during falling, low, and rising tide stages on the left
and right banks, Kenai River, 2002.............................................................................................................................24
10. Vertical distributions of late-run upstream and downstream fish on the left and right banks, Kenai
River, 2002.......................................................................................................................................................................25
11. Vertical distributions of late-run upstream fish during falling, low, and rising tide stages on the left and
right banks, Kenai River, 2002.....................................................................................................................................26
12. Range distributions of early-run upstream and downstream migrating fish on the left and right banks,
Kenai River, 2002...........................................................................................................................................................27
13. Range distributions of early-run upstream fish during falling, low, and rising tide stages on the left and
right banks, Kenai River, 2002.....................................................................................................................................28
14. Range distributions of late-run upstream and downstream migrating fish on the left and right banks,
Kenai River, 2002...........................................................................................................................................................29
15. Range distributions of late-run upstream migrating fish during falling, low, and rising tide stages on
the left and right banks, Kenai River, 2002................................................................................................................30
16. Early-run target strength distributions for all upstream and downstream targets on the left and right
banks, Kenai River, 2002..............................................................................................................................................32
17. Late-run target strength distributions for all upstream and downstream targets on the left and right
banks, Kenai River, 2002..............................................................................................................................................33
18. Daily sonar estimates of passage by bank (top panel), total passage (center panel), and historical
cumulative proportions for the early run of Chinook salmon returning to the Kenai River, 2002...................34
19. Daily sonar estimates of passage by bank (top panel), total passage (center panel), and historical
cumulative proportions for the late run of Chinook salmon returning to the Kenai River, 2002.....................35
20. Daily CPUE of Chinook and sockeye salmon from inriver netting, early run (16 May-30 June), Kenai
River, 2002.......................................................................................................................................................................42
21. Daily discharge rates collected at the Soldotna Bridge, Secchi depth readings taken in front of the
sonar site, Chinook sonar passage estimates, inriver gillnet CPUE, and Chinook sport fish CPUE, early
run (16 May-30 June), Kenai River, 2002..................................................................................................................43
22. Estimated early- (top) and late-run (bottom) Chinook salmon passage based on unfiltered sonar counts,
net-apportioned sonar counts, and standard (filtered) sonar counts, Kenai River, 2002....................................44
23. Daily discharge rates collected at the Soldotna Bridge, Secchi depth readings taken in front of the
sonar site, Chinook sonar passage estimates, inriver gillnet CPUE, river mile-19 sockeye sonar passage
estimates, and Chinook sport fish CPUE, late run (1 July-5 August), Kenai River, 2002.................................46

iv
LIST OF APPENDICES
Appendix Page
A1. The sonar equation used to estimate target strength with dual- and split-beam applications............................54
B1. Sonar coverage near the thalweg..................................................................................................................................56
C1. Example of system parameters used for data collection on the right bank (transducer 733)............................70
C2. Example of system parameters used for data collection on the left bank (transducer 738)...............................73
D1. Inseason data flow diagram for the Kenai River Chinook salmon sonar project, 2002.....................................78
E1. Hourly samples excluded by bank from calculation of early- and late-run Chinook salmon daily
passage estimates, Kenai River, 2002.........................................................................................................................80
F1. Daily proportions of upstream and downstream fish for the 2002 Kenai River early Chinook run.................82
F2. Daily proportions of upstream and downstream fish for the 2002 Kenai River late Chinook run...................83
G1. Average vertical angle by tide stage and orientation for the 2002 Kenai River early Chinook run.................86
G2. Average vertical angle by tide stage and orientation for the 2002 Kenai River late Chinook run...................87
H1. Kenai River early-run Chinook salmon sonar passage estimates, 1987-2002.....................................................90
H2. Kenai River late-run Chinook salmon sonar passage estimates, 1987-2002........................................................92
I1. Filtered (conventional), unfiltered, and net-apportioned Chinook passage estimates, Kenai River sonar,
early run, 2002.................................................................................................................................................................96
I2. Filtered (conventional), unfiltered, and net-apportioned Chinook passage estimates, Kenai River sonar,
late run, 2002...................................................................................................................................................................97
J1. Echo length standard deviation mixture model and estimates derived from this model, Kenai River
Chinook early run, 2002.............................................................................................................................................100

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