Zack Larson and Associates
Dual-frequency Identification Sonar (DIDSON) is promising new
technology for enumerating anadromous fish in rivers. DIDSON is a
multi-beam, high-definition imaging sonar that produces video-like
images of fish and can detect fish as far as 80 meters away. DIDSON is
generally positioned in the water near the bank to view a cross section
of the channel. Fish are imaged and counted as they pass through the
sonar beams. Unbiased fish counts and reasonably accurate length
measurements can be derived.
The Alaska Department of Fish and Game (ADF&G) has tested
DIDSON for counting salmon in rivers and the technology has
consistently exceeded their expectations for counting salmon. They
also find the technology increases their confidence in overall fish
passage numbers, improves their credibility with user groups and
ultimately makes fisheries management decisions easier.
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Investigate the usefulness of DIDSON for
monitoring salmon and steelhead abundance in
coastal California Rivers.
Develop standardized approaches to operating
sonar fish counting stations on North Coast rivers.
Complement ongoing fisheries research
Help California achieve anadromous fisheries
management objectives.
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CDFG Fisheries Restoration Grants Program
Steelhead Report Card
County of Del Norte
Smith River Advisory Council
Smith River Alliance
California Trout
Humboldt State University
Alexandre EcoDairy Farms
Sound Metrics Corporation
Ocean Marine Industries
2008 Smith River DIDSON Workshop
Northern California FFF
Zack Larson & Associates (Project Leader)
The Smith River Sonar Station is located 6 river miles from the
Pacific Ocean at the Public Boat Launch Facility off Fred Haight
Drive near the town of Smith River.
Two Long Range DIDSON units are deployed
from both sides of the Smith River 24 hours per
day, 7 days per week from October 1 to April 15th.
Data is recorded in 20 and 30 minute files and
immediately processed in an onsite utility
building connected to grid power.
Justin Garwood, DFG
Three fish observed from
22 meters to 25 meters
from shore
Length measurements of
targets can be recorded
with the Sound Metrics
DIDSON software. The
individual fish shown to
the right is approximately
3.7 feet or 44 inches in
length.
1200
9000
8000
7000
1000
800
6000
5000
600
4000
400
3000
2000
1000
200
# Downstream
RCFH Chinook
RCFH Steelhead
Oct. 25 - 30
Nov. 1 - 7
Nov. 8 - 15
Nov. 16 - 23
Nov. 24 - Dec. 1
Dec. 2 - Dec. 9
Dec. 10 - Dec. 17
Dec. 18 - Dec. 25
Dec. 26 - Jan. 2
Jan. 3 - Jan. 10
Jan. 11 - Jan. 18
Jan. 19 - Jan. 26
Jan. 27 - Feb. 3
Feb. 4 - Feb. 11
Feb. 12 - Feb. 19
Feb. 20 - Feb. 27
Feb. 28 - Mar. 7
Mar. 8 - Mar. 15
Mar. 16 - Mar. 23
Mar. 24 - Mar. 31
Apr. 1 - Apr. 8
Apr. 9 - Apr. 15
# Upstream
0
0
EMPIRICAL DATA
Total Upstream Detections
Total Downstream Detections
Net Upstream Detections
43,479
11,235
32,234
Chinook salmon and steelhead estimates
25 Oct – 15 Dec (Chinook salmon):
Net Upstream Detections
21,958
16 Dec – 15 Apr (Steelhead)
Total Upstream Detections
12,475
Smith River DIDSON Pilot Study:
Upstream Fish Counts and River Discharge, October 2011
650
650
547
512
540
550
550
461
450
423
349
350
284
242
250
364
369
333
281272
244
350
267
250
179
142
150
75
89
73
61
50
-50
113 150
98
67
70
50
2
Oct. 1
Oct. 2
Oct. 3
Oct. 4
Oct. 5
Oct. 6
Oct. 7
Oct. 8
Oct. 9
Oct. 10
Oct. 11
Oct. 12
Oct. 13
Oct. 14
Oct. 15
Oct. 16
Oct. 17
Oct. 18
Oct. 19
Oct. 20
Oct. 21
Oct. 22
Oct. 23
Oct. 24
Oct. 25
Oct. 26
Oct. 27
Oct. 28
Oct. 29
Oct. 30
Oct. 31
Numbers of Fish
394
-25
-114
-150
Date
-12
-19
-50
-150
Flow (cfs x 10)
450
# FISH
FLOW x1
(cfs)
SONAR STATION EFFICIENCY
2010/2011
WEEK
#UPSTREAM
Oct. 25 - 30
Nov. 1 - 7
Nov. 8 - 15
Nov. 16 - 23
Nov. 24 - Dec. 1
Dec. 2 - Dec. 9
Dec. 10 - Dec. 17
Dec. 18 - Dec. 25
Dec. 26 - Jan. 2
Jan. 3 - Jan. 10
Jan. 11 - Jan. 18
Jan. 19 - Jan. 26
Jan. 27 - Feb. 3
Feb. 4 - Feb. 11
Feb. 12 - Feb. 19
Feb. 20 - Feb. 27
Feb. 28 - Mar. 7
Mar. 8 - Mar. 15
Mar. 16 - Mar. 23
Mar. 24 - Mar. 31
Apr. 1 - Apr. 8
Apr. 9 - Apr. 15
#DOWNSTREAM TOTAL UPSTREAM FISH % FISHING EFFICIENCY
2304
3831
7502
8166
5203
3071
1209
986
1121
1507
1805
1556
769
655
1159
1033
592
182
269
159
183
217
801
#VALUE!
42.44%
49.56%
78.22%
85.88%
88.57%
92.60%
88.45%
82.56%
79.20%
97.15%
97.76%
97.80%
96.89%
98.22%
97.50%
96.95%
80.04%
38.44%
87.27%
80.30%
99.17%
99.61%
1503
#VALUE!
2052
2758
1490
741
189
104
93
141
94
78
132
193
167
233
156
66
132
100
126
314
5450
5408
3713
2330
1020
882
1028
1366
1711
1478
637
462
992
800
436
116
137
59
57
-97
2011/2012
WEEK
# UPSTREAM
# DOWNSTREAM
TOTAL UPSTREAM FISH
FISHING EFFICIENCY
Oct. 1-8
6647
3378
3269
86.34%
Oct. 9-16
6080
3158
2922
98.69%
Oct. 17-24
6453
5956
497
98.95%
Oct. 25-Nov.1
6191
5646
545
98.71%
25371
18138
7233
95.97%
Running Total
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Construction and permitting
DIDSON LR package
Operating costs (2-years)
Del Norte Co. Administration
$18,901
$96,220
$279,907
$29,881
TOTAL COST (DFG)
SRA COST MATCH
$424,90
$69,487
ANNUAL OPERATING COSTS
$140,000