https://doi.org/10.25923/vnxd-a710

NOAA Technical Memorandum NMFS

AUGUST 2018

REPORT ON THE SWFSC’S COLLECTION OF DATA DURING THE 

2015 JOINT U.S.-CANADA INTEGRATED ACOUSTIC AND TRAWL 

SURVEY OF PACIFIC HAKE AND COASTAL PELAGIC SPECIES

(SaKe 2015; 1507SH) WITHIN THE CALIFORNIA CURRENT 

ECOSYSTEM, 15 JUNE TO 10 SEPTEMBER 2015, CONDUCTED 

ABOARD FISHERIES SURVEY VESSEL BELL M. SHIMADA

Kevin L. Stierhoff, Juan P. Zwolinski, Josiah S. Renfree,

Scott A. Mau, David W. Murfin, and David A. Demer

Fisheries Resources Division

Southwest Fisheries Science Center

NOAA National Marine Fisheries Service

8901 La Jolla Shores Dr.

La Jolla, CA 92037, USA

NOAA-TM-NMFS-SWFSC-603

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Southwest Fisheries Science Center
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Recommended citation

Stierhoff, Kevin L., Juan P. Zwolinski, Josiah S. Renfree, Scott A. Mau, David W. Murfin, 

and David A. Demer. 2018. Report on the SWFSC’s collection of data during the 2015 

Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake and Coastal 

Pelagic Species (SaKe 2015; 1507SH) within the California Current Ecosystem, 15 June 

to 10 September 2015, conducted aboard Fisheries Survey Vessel Bell M. Shimada. U.S. 

Department of Commerce, NOAA Technical Memorandum NMFS-SWFSC-603. 33 p.

https://doi.org/10.25923/vnxd-a710
I. Introduction 

The 2015 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacifc Hake and Coastal Pelagic 

Species (SaKe 2015; 1507SH) was conducted aboard NOAA Fisheries Survey Vessel (FSV) Bell M. Shimada

(hereafter, Shimada), 15 June to 10 September 2015. The Acoustic-Trawl Method (ATM) was used to assess 

coastal pelagic fsh species (CPS) and krill within the California Current Ecosystem (CCE). Data were 

collected using multi-frequency echosounders, surface trawls, vertically and obliquely integrating net tows, a 

continuous underway fsh-egg sampler (CUFES), and conductivity-temperature-depth probes (CTDs). 

The SWFSC’s objectives for the survey were to: 1) acoustically map the distributions and estimate the 

abundances of CPS, i.e., Pacifc sardine (Sardinops sagax), Northern anchovy (Engraulis mordax), Pacifc 

herring (Clupea pallasii), Pacifc mackerel (Scomber japonicus), and jack mackerel (Trachurus symmetricus); 

and krill (euphausiid spp.); 2) characterize their biotic and abiotic environments, and investigate linkages; 

and 3) gather information regarding their life history parameters. Reported elsewhere, the Northwest Fisheries Science Center (NWFSC) concurrently surveyed hake (Merluccius productus). The survey domain 

encompassed the anticipated distributions of the northern sub-population of sardine and the central and 

northern sub-populations of anchovy o ̇ the west coasts of the U.S. and Canada from approximately San 

Diego, CA to Haida Gwaii, British Columbia. The survey domain was defned by the modeled distribution 

of sardine potential habitat (Zwolinski et al., 2011), and information recently gathered from other research 

projects (e.g., California Cooperative Fisheries Investigations (CalCOFI) samples) or the fshing industry 

(e.g., sardine bycatch). 

This report provides an overview of the survey objectives and a summary of the survey equipment, acousticsystem calibration, sampling and analysis methods, and preliminary results. The biomass of the northern 

stock of Pacifc sardine is presented in Zwolinski et al. (2016). This report does not include estimates of the 

distributions and biomasses for other CPS, krill, or hake. 

1 
I.1 Scientifc Personnel 

As elaborated below, the collection and analysis of the survey data was conducted by the SWFSC1, and 

NWFSC2. Superscripts denote aÿliations and roles of the other cruise participants: 1-SWFSC, 2-NWFSC, 

3-Chief Scientist, 4-Field Party Chief, and 5-Lead Biologist. 

Project Leads: 

• D. Demer1

• L. Hufnagle2

Acoustic Data Collection and Processing: 

• Leg I: J. Clemons2,4, S. Parker-Stetter2, J. Pohl2, J. Renfree1, and J. Zwolinski1,3

• Leg II: J. Clemons2,3, S. Mau1, and R. Thomas2

• Leg III: D. Chu2, S. de Blois2,3,4, V. Maynez1, D. Murfn1, and S. Parker-Stetter2

• Leg IV: J. Pohl2,3, J. Renfree1, and R. Thomas2

Trawl Sampling: 

• Leg I: C. Colway2, J. Evanilla1, E. Gardner1, B. Macewicz1, S. Manion1,3, K. Miller1, T. Mitchell2, A. 

Odell2, H. Villalobos1, C. Whiteside2,5, and P. Y Chen1

• Leg II: A.L. Ahern2, S. Manion1,3, S. Deery-Schmitt2, K. Gilmore1, D. Griÿth1, M. Seibert1, M. 

Ushido2, W. Watson1, and B. Whiteside2,5

• Leg III: S. Deery-Schmitt2, A. Hays1, D. Kamikawa2,5, A. Kester2, B. Macewicz1, C. Purdy1, M. 

Sedarat1, A. Thompson1, and E. Weber1

• Leg IV: A. Billings2,5, E. Brasseur2, K. Byers1, S. Charter1, S. Deery-Schmitt2, B. Flores1, D. 

Griÿth1,3, and A. Lowe1

Echosounder Calibration: 

• D. Demer1, J. Pohl2, J. Renfree1, J. Zwolinski1

2 
II. Methods 

II.1. Survey region and design 

During spring, sardine typically aggregate o ̇shore of central and southern California to spawn (Demer et

al., 2012, and references therein). During summer, if the stock is large enough, adults will migrate north, 

compress along the coast, and feed in the upwelled regions (Figure II.1). 

Figure II.1. Conceptual map showing the average spring and summer distributions of the northern subpopulation of Pacifc sardine potential habitat during spring and summer along the west coasts of Mexico, 

the United States, and Canada (Zwolinski et al., 2014). 

3 
During summer 2015, the west coast of the United States was surveyed using Shimada. Compulsory transects 

were nearly perpendicular to the coast with separations of 10 to 20 nmi. The survey began o ̇ San Diego, CA 

and progressed northwards toward Haida Gwaii, British Columbia, frst sampling the central sub-population 

of anchovy o ̇ southern and central California. 

The planned transects (Figure II.2) spanned the latitudinal extent of the potential habitat of the northern 

sub-population of sardine at the time of the survey (Figure II.3; http://swfscdata.nmfs.noaa.gov/AST/ 

sardineHabitat/habitat.asp). Transect positions, lengths, and spaces were adjusted according to the expected 

distributions of sardine and anchovy at the time of the survey. 

Figure II.2. Planned compulsory transect lines. 

4 
Figure II.3. Distribution of potential habitat for the northern stock of Pacifc sardine on 15 June 2015 at 

the beginning of SaKe 2015. 

5 
II.2 Acoustic sampling 

II.2.1. Echosounders 

Multi-frequency (18, 38, 70, 120, and 200 kHz) General Purpose Transceivers (Simrad EK60 GPTs) and 

Wideband Transceivers (Simrad EK80 WBTs; 70 and 200 kHz only) were confgured with split-beam transducers (Simrad ES18-11, ES38B, ES70-7C, ES120-7C, and ES200-7C, respectively). The transducers were 

mounted on the bottom of a retractable keel or “centerboard” (Figure II.4). The keel was retracted (transducers ~5-m depth) during calibration, and extended to the intermediate position (transducers ~7-m depth) 

during the survey. Exceptions were made during shallow water operations, when the keel was retracted; 

or during times of heavy weather, when the keel was extended (transducers ~9-m depth) to provide extra 

stability and reduce the e ̇ect of weather-generated noise (Appendix A). 

Figure II.4. Transducer locations on the bottom of the centerboard aboard Shimada. 

II.2.2. Calibration 

Prior to calibration (15 June 2015 at ~1900), the integrity of each transducer was verifed through impedance 

measurements of each transducer using an LCR meter (Agilent Model E4980A) and custom Matlab software. 

For each transducer, impedance magnitude (|Z|), phase (), conductance (G), susceptance (B), resistance 

(R), and reactance (X) was measured at the operational frequencies with the transducer quadrants placed in 

parallel. The echosounders were calibrated using the standard sphere technique (Demer et al., 2015; Foote 

et al., 1987). The reference target was a 38.1-mm diameter sphere made from tungsten carbide (WC) with 

6% cobalt binder material (NWFSC sphere; sphere number unknown). The GPTs were confgured, via the 

ER60 software, using the parameters in Table III.1 (below). 

II.2.3. Data collection 

The ER60-computer clock was set to Universal Coordinated Time (UTC) and synchronized with the GPS 

clock using SymmTime (Symmetricon, Inc.) every six hours. Echosounder pulses were transmitted simultaneously at all frequencies, at variable intervals, as controlled by the ER60 Adaptive Logger (EAL, Renfree 

and Demer, 2016). The EAL optimizes the pulse interval, based on the seabed depth, while minimizing 

aliased seabed echoes. Acoustic sampling for CPS-density estimation along the pre-determined transects 

(see Section II.1) was limited to daylight hours (approximately between sunrise and sunset). 

6 
Measurements of volume backscattering strength (S v; dB re 1 m2 m-3) and target strength (TS; dB re 1 

m2), indexed by time and geographic positions provided by GPS receivers, were logged to 700-m range, and 

stored in Simrad .raw format (50-MB maximum fle size; each flename begins with “1507SH_” and ends 

with the logging commencement date and time) using the GPT-control software (Simrad ER60 V2.4.3). 

To minimize acoustic interference, transmit pulses were triggered using the EAL and TriggerJigger (Alaska 

Fisheries Science Center). All other instruments that produce sound within the echosounder bandwidths 

were secured during survey operations. Exceptions were made during stations (e.g., plankton sampling and 

fsh trawling) or in shallow water when the vessel’s command occasionally operated the bridge’s 50- and 

200-kHz echosounders (Furuno), the Doppler velocity log (Sperry Marine Model SRD-500A), or both. 

II.2.4. Data processing 

The calibrated echosounder data were processed on a dedicated computer, using commercial software 

(Echoview V6.1.40.26321, Echoview Software Pty Ltd.) and the following procedure: 

1. For each transect, the associated data fles (.raw format) were loaded into an Echoview (.ev) fle. 

Transducer depths were set to 0 m. 

2. In each .ev fle, values for the environment were set using Echoview calibration supplement (.ecs) fles, 

including data from the closest CTD or UCTD cast. Since the CPS of interest reside in the upper 

mixed layer, environment data were averaged over 0- to 70-m depth. 

3. For each frequency: 

• Echograms of Sv were displayed. 

• “Noise-reduced” echograms (Figure II.5a), generated by subtracting in the linear domain simulated background noise from the raw Sv, were smoothed by computing the median value in 

non-overlapping 11-sample by 3-ping cells (Figure II.5b). 

• The smoothed, noise-reduced echograms were used to calculate Sv-di ̇erences using the 38-kHz 

Sv (Sv38kHz) as a reference (i.e., Sv70kHz - Sv38kHz; Sv120kHz - Sv38kHz; Sv200kHz - Sv38kHz). 

• A CPS mask (Figure II.5c) was created for regions where Sv-di ̇erences were within the expected 

ranges for CPS (Table II.1.). 

• Data were provisionally ascribed to CPS if their Sv-di ̇erences (i.e., Sv70kHz - Sv38kHz; Sv120kHz

- Sv38kHz; Sv200kHz - Sv38kHz) were within predicted ranges (Table II.1.). 

• Data collected when the ship approached or departed a sampling station, typically associated 

with a ship-speed less than 4 kn, were automatically marked as “bad data.” 

• Provisional CPS regions created above were ascribed to CPS schools if the standard deviation of 

each 11-sample by 3-ping cell was > -50 dB at 120 and 200 kHz. 

• The 38-kHz CPS data with Sv < -60 dB (corresponding to a density of approximately three fsh 

per 100 m3 in the case of 20-cm-long sardine) were set to -999 dB (e ̇ectively zero; Figure II.5d). 

• An integration-start line was created at a range of 5 m from the transducers. When necessary, 

this line was manually modifed to exclude reverberation due to bubbles. 

• The depth of the top of the dead-zone was estimated using the variance-to-mean ratio (Demer et

al., 2009). 

• An integration-stop line was created at 250-m depth or, when shallower, 3 m above the estimated 

depth of the top of the dead-zone. 

• Between the integration lines, to a maximum of 250 m, volume backscattering coeÿcients (sv, m2

m-3) were integrated over 5-m depths and averaged over 100-m distances. The resulting integrated 

volume backscattering coeÿcients (sA; m2 nmi-2), for each transect and frequency, were output 

to comma-delimited text (.csv) fles. 

• The sA values were summed over ranges from the integration start line to the approximate depth 

of the bottom of the upper mixed layer. 

• Data collected during daytime (i.e., not earlier than 30 min before sunrise to not later than 30 min 

after sunset) were averaged over 2-km distances, and mapped. Nighttime data, assumed to be 

negatively biased due to diel-vertical migration (DVM) and disaggregation of the target species’ 

schools (Cutter and Demer, 2008; Demer and Hewitt, 1995) were omitted. 

7 
Figure II.5 Synchronized echograms of 38-kHz Sv after a) noise-subtraction, b) median smoothing, c) 

masking, and d) 38-kHz Sv thresholding at -60 dB (fnal, CPS-only). 

Table II.1. Sv-di ̇erences (minimum, maximum; dB) for putative CPS. 

Sv70kHz − Sv38kHz Sv120kHz − Sv38kHz Sv200kHz − Sv38kHz

-12.85, 9.89 -13.15, 9.37 -13.51, 12.53 

II.3. Trawl sampling 

During the day, CPS form schools in the upper mixed layer (to 70-m depth in the spring; Kim et al., 2005), 

and much shallower in summer. After sunset, CPS schools tend to ascend and disperse. At that time, with 

reduced visibility and no schooling behavior, they are less able to avoid a net (Mais, 1974). Therefore, trawl 

sampling for identifying the species composition and length distributions of acoustic targets was performed 

at night. 

The net, a Nordic 264 rope trawl (NET Systems; Bainbridge Island, WA), has a rectangular opening in the 

fshing portion of the net with an area of approximately 300 m2 (~15-m tall x 20-m wide), variable-sized 

mesh in the throat, an 8-mm square-mesh cod end liner (to retain a large range of animal sizes), and a 

“marine mammal excluder device” to prevent the capture of large animals, such as dolphins, turtles, or 

sharks (Dotson et al., 2010). The trawl doors are foam-flled and the trawl headrope is lined with foats so 

the trawl tows at the surface. 

Nighttime trawl sampling was conducted where echoes from CPS schools were observed earlier that day. 

Trawls were towed at ~ 4 kn for 45 min. The total catch from each trawl was weighed and sorted by species or 

groups. From the catches with CPS, up to 75 fsh were selected randomly for each of the target species. Those 

were weighed (g) and measured to either their standard length (Ls; mm) for sardine, anchovy, and herring, 

or fork length (Lf; mm) for jack mackerel and Pacifc mackerel. In addition, otoliths were removed, sex and 

maturity recorded, and fn clips preserved in ethanol from up to 50 of the randomly selected individuals of 

each species. Regional species composition was estimated from the nearest trawl cluster, i.e., the combined 

catches of up to three trawls per night, separated by ~ 10 nmi. 

8 
II.4. Ichthyoplankton and oceanographic sampling 

II.4.1. Egg and larva sampling 

During the day, fsh eggs were collected using CUFES (Checkley et al., 1997), which collects water and 

plankton at a rate of ~640 l min-1 from an intake on the hull of the ship at ~ 3-m depth. The particles in the 

sampled water were sieved by a 505 μm mesh. Sardine, anchovy, jack mackerel, and hake eggs are identifed 

to species, counted, and logged. Typically, the duration of each CUFES sample was 30 min, corresponding 

to a distance of 5 nmi at a speed of 10 kn. Because the duration of the initial stages of the egg phase is short 

for most fsh species, the egg distributions inferred from CUFES indicate the nearby presence of actively 

spawning fsh. 

A CalCOFI bongo oblique (or bongo) net (a paired, bridleless, 71-cm diameter net with 505-μm mesh; 

Smith and Richardson, 1977) was used to sample ichthyoplankton and krill at one station each day soon 

after sunset. Where there was adequate depth, 300 m of wire was deployed at a rate of 50 m min-1 and then 

retrieved at 20 m min-1, at a nominal wire angle of 45. Bongo samples were stored in 5% formalin. Paired 

vertical egg tow (PairoVET; Smith et al., 1985) nets (25-cm diameter; 150-μm mesh) were used to sample 

fsh eggs and larvae from a depth of 70 m to the sea surface at a rate of 70 m min-1 at the same locations 

where bongo nets were deployed. These PairoVET samples were preserved in 95% ethanol for future genetic 

analysis. 

II.4.2. Conductivity and temperature versus depth (CTD) sampling 

Day and night, conductivity and temperature versus depth to 350 m were measured with calibrated sensors 

on a CTD rosette or underway probe (UCTD) cast from the vessel. These data were used to estimate the 

time-averaged sound speed (Demer, 2004), for estimating ranges to the sound scatterers, and frequencyspecifc sound absorption coeÿcients, for compensating signal attenuation of the sound pulse between the 

transducer and scatters (Simmonds and MacLennan, 2005). These data also provided indication of the depth 

of the upper-mixed layer, where most epipelagic CPS reside during the day. 

9 
III. Results 

III.1. EK60 echosounder calibration 

The EK60s were calibrated on 19 June 2015 (~2300 GMT) while the vessel was at anchor near Shelter 

Island, San Diego Bay (32.7135 N, -117.2227 W, Figure III.1). Thermosalinograph (Seabird Model 

SBE38) measurements of sea-surface temperature (tw = 19.68 C) and salinity (sw = 33.57 psu) were input 

to the GPT-control software, which derived estimates of sound speed (cw = 1519 m s-1) and absorption 

coeÿcients (see Table III.1). Varying with tide, the seabed was approximately 8 to 12 m beneath the 

transducers. The calibration sphere was positioned 4.5 to 7 m below the transducers. 

GPT information, confguration settings, and beam model results following calibration are presented in 

Table III.1. Measurements of beam-uncompensated sphere target strength (TS u, dB re 1 m2) are plotted 

in Figure III.2 and relative beam-compensated sphere target strength (TSrel, dB re 1 m2) are plotted in 

Figure III.3. A time-series of calibration results for Shimada, including on-axis gain (G0), Sa Correction 

(Sacorr), beamwidths (−3dB and −3dB), o ̇set angles (0 and 0), and RMS, are plotted in Figure III.4. 

Figure III.1. Map of the calibration location (yellow diamond) near Shelter Island, San Diego Bay. The 

red box in the inset indicates the location and extent of the main map. 

10 
	

Table III.1 Simrad EK60 general purpose transceiver (GPT) information, pre-calibration settings, and 

beam model results following calibration (below horizontal line). Prior to the survey, on-axis gain (G0), 

beam angles and angle o ̇sets, and Sa Correction (Sacorr) values from calibration results were entered into 

the GPT-control software (Simrad ER60). 

Frequency (f, kHz) Units 18 38 70 120 200 

Model ES18-11 ES38B ES70-7C ES120-7C ES200-7C 

Serial Number 2065 30715 168 573 339 

Transmit Power (pet) W 2000 2000 750 250 100 

Pulse Duration ( ̋ ) ms 1.024 1.024 1.024 1.024 1.024 

On-axis Gain (G0) dB re 1 23.16 26.14 26.1 26.02 25.39 

Sa Correction (Sacorr) dB re 1 -0.74 -0.57 -0.34 -0.35 -0.36 

Bandwidth (Wf) Hz 1570 2430 2860 3030 3090 

Sample Interval m 0.194 0.194 0.194 0.194 0.194 

Eq. Two-way Beam Angle ( ) 

Absorption Coeÿcient (f) 

dB re 1 sr 

dB km−1

-18 

1.9 

-21.4 

7.5 

-21.5 

21.2 

-20.8 

44.2 

-20.8 

71.4 

Angle Sensitivity Along. () Elec./Geom. 13.68 21.62 22.64 22.78 22.69 

Angle Sensitivity Athw. () Elec./Geom. 13.68 21.62 22.64 22.78 22.69 

3-dB Beamwidth Along. (−3dB) deg 11.22 7.04 6.67 6.42 6.55 

3-dB Beamwidth Athw. (−3dB) deg 11.28 7.1 6.73 6.45 6.49 

Angle O ̇set Along. (0) deg -0.21 -0.01 -0.13 0.05 0.03 

Angle O ̇set Athw. (0) 

Theoretical TS (T Stheory) 

Ambient Noise 

deg 

dB re 1 m2

dB re 1 W 

0.22 

-42.46 

-0.02 

-42.39 

0.04 

-41.62 

0.11 

-39.73 

-0.08 

-38.82 

On-axis Gain (G0) dB re 1 23.05 25.96 26.33 25.8 25.23 

Sa Correction (Sacorr) dB re 1 -0.78 -0.57 -0.34 -0.37 -0.22 

RMS dB 0.32 0.16 0.15 0.21 0.31 

3-dB Beamwidth Along. (−3dB) deg 10.96 6.98 6.46 6.57 6.71 

3-dB Beamwidth Athw. (−3dB) deg 11.1 6.94 6.51 6.63 6.68 

Angle O ̇set Along. (0) deg -0.19 0.02 -0.09 0.03 0.02 

Angle O ̇set Athw. (0) deg 0.24 -0.01 0.05 0.1 -0.07 

11 
Figure III.2. Beam-uncompensated sphere target strength (TSu, dB re 1 m2) measurements of a 38.1-

mm diameter sphere made from tungsten carbide (WC) with 6% cobalt binder material, at multiple EK60 

frequencies (18, 38, 70, 120, and 200 kHz). Crosses indicate measurements marked as outliers after viewing 

the beam model results. 

Figure III.3. Relative beam-compensated sphere target strength (TSrel, dB re 1 m2) measurements of a 

38.1-mm diameter sphere made from tungsten carbide (WC) with 6% cobalt binder material, at multiple 

EK60 frequencies (18, 38, 70, 120, and 200 kHz). TSrel is calculated as the di ̇erence between the beamcompensated target strength (TSc) and the theoretical target strength (TStheory, see Table III.1). Crosses 

indicate measurements marked as outliers after viewing the beam model results. 

12 
Figure III.4. Time series of beam model results of a) on-axis gain (G0, dB); b) Sa correction (S acorr, dB 

re 1); c) alongship (−3dB, blue) and athwartship (−3dB, red) beamwidths (deg); d) alongship (0, blue) 

and athwartship (0, red) o ̇set angles (deg.); and e) RMS (dB) for each EK60 transducer frequency aboard 

Shimada. Unflled circles indicate results from the current survey. 

13 
III.2. Data collection 

III.2.1. Acoustic and trawl sampling 

The survey spanned an area from approximately Haida Gwaii, British Columbia to San Diego, CA (Figure 

III.5), with 79 east-west transects totaling 3150 nmi, and 158 Nordic trawls. 

Leg I 

On 20 June, Shimada departed San Diego and began the frst transect that day at ~1300 (all times UTC). 

On 3 July, Shimada arrived at Pier 15 in San Francisco, CA at ~2300 to end Leg I. 

Leg II 

On 8 July 2015, Shimada departed Pier 15 in San Francisco, CA at ca. 1700, and arrived at the frst station 

(Station 18.1 on transect 18; 35 nmi. east of Santa Cruz, CA) at ~1800 on 8 July to resume survey operations. 

The ship’s intercooler was leaking and repaired on 7 July, which delayed departure by one day. Foul weather 

made trawling diÿcult beginning on 15 July. Multiple CTD casts were made during the night shift on 15 

July instead of trawling; due to foul weather, no trawling was conducted on 16 July. The hydraulic pump 

operating the ship’s rudder malfunctioned for approximately one hour, after which the survey resumed using 

the backup pump. On 20 July, the ME70 ping rate became very slow. The laptop computer controlling 

the TriggerJigger fell from the rack and pulled the trigger cable from the EK60, which removed the trigger 

from the EK60 and caused the whole system to slow. On 22 July, transect 36 was briefy interrupted when 

the cooling line for the propeller shaft failed and required repair. At one point, the bridge ER60 was run 

in passive slave mode while trawling for hake, which caused the EAL to crash; disabling the EAL while 

operating the bridge ER60 in passive slave mode stopped the EAL from crashing. On 26 July, Shimada

returned to the NOAA Pier, MOC-P in Newport, OR at ~1600 to end Leg II. 

Leg III 

On 5 August, Shimada departed from NOAA Pier, MOC-P in Newport OR, at ~1730, and arrived at the 

frst station (transect 40 near Heceta Head) at ~2100 on 5 August to resume survey operations. On 5 

August, upon sampling transect 40, communications to all EK60 GPTs except 200-kHz were lost and could 

not be reestablished via the ER60 software. All GPTs were disconnected from the Z-Mux junction box and 

communications were reestablished; no GPTs were connected to the Z-Mux for the remainder of Leg III. On 

13 August, acoustic sampling was interrupted for ~45 min when Shimada’s main power transformer failed. 

On 15 August, the trawl gate began leaking hydraulic fuid and was secured by the ship’s crew. With the 

trawl gate inoperable, it was diÿcult for the crew to manage the nets and damage occurred to both the 

hake and CPS trawl nets. Further, a joint SWFSC/NWFSC study was performed to inspect potential noise 

generated on the EK60s from Shimada’s propeller speed, connections to the Z-Mux, or both. On 19 August, 

a second calibration of the EK60 echosounders was conducted by the NWFSC in Shilshole Bay near Seattle, 

WA (37.7867 N, -122.3843 W; results not shown). On 20 August, Shimada returned to Pier 90 in Seattle, 

WA at ~2300to end Leg III. 

During Leg III, aerial surveys of CPS were conducted by Frank Foode in coordination with Shimada. Analysis of those data are ongoing. On 18 August, acoustic data were collected using 70- and 200-kHz EK80 

echosounders outside the straight of Juan de Fuca near Seattle, WA for comparison with EK60 data collected 

along transect 55. 

Leg IV 

On 23 August, Shimada departed from Pier 90 in Seattle, WA at ~1800 and arrived at the eastern end of 

transect 57 at ~1330 on 24 August to resume survey operations. On 25 August, transect 57 was extended 

westward due to presence of hake. On 26 August, transect 59 was also extended westward due to presence 

of hake. On 26 August, sardine eggs were collected in CUFES at ~2100 but there was no putative CPS 

backscatter in the EK60 echograms. On 27 August, acoustic sampling was interrupted between ~18:45 and 

19:00 to troubleshoot the starboard power-steering pump. On 10 September, Shimada returned to MOC-P 

in Newport, OR at ~2030 to conclude survey operations. 

14 
Figure III.5. Cruise track of Shimada (gray line), east-west acoustic transects (black lines), and locations 

of surface trawls (white points) superimposed on the vessel track (light gray lines). Transects north of 

Vancouver Island were planned ad hoc for investigating the northern extent of the hake distribution. 

15 
III.2.2 Ichthyoplankton and oceanographic sampling 

A total of 126 CTD casts, 59 bongo tows, and 27 PairoVET tows were conducted throughout the survey. In 

addition, 166 UCTD casts were conducted and 941 CUFES samples were collected underway. The locations 

of CTD and UCTD stations are shown in Figure III.6 and Appendix C. 

Figure III.6. Locations of CTD and UCTD casts (red circles) and plankton net samples (bongo net in 

orange triangles; PairoVET net in green triangles) relative to the vessel track (bold gray line), acoustic 

transects (black lines), and proposed transects (light gray lines). 

16 
III.3. Distribution of CPS 

Acoustic backscatter ascribed to CPS was observed throughout the survey area, but was most prevalent 

between the Columbia River and Cape Blanco, inshore between Bodega Bay and Morro Bay, CA, and 

inshore of the northern Channel Islands in the Southern California Bight (Figure III.7a). 

Jack mackerel eggs were the most abundant of any CPS species and were present in the CUFES throughout 

most of the survey area. Jack mackerel eggs were most abundant in the o ̇shore portion of transects between 

the Columbia River and Bodega Bay and south of Monterey Bay (Figure III.7b). Sardine eggs were 

observed in the CUFES south of the Columbia River o ̇ Oregon; between Cape Blanco and Crescent City, 

CA; and between Point Arena (north of Bodega Bay) and Monterey Bay (Figure III.7b). Anchovy eggs 

were present in the CUFES samples o ̇ the Columbia River, nearshore between Point Conception and Long 

Beach, CA, and to a lesser extent in the Gulf of the Farallones near San Francisco (Figure III.7b). 

Jack mackerel comprised the greatest proportion of catch in trawl samples between Cape Flattery and Cape 

Mendocino, and along the central CA coast between San Francisco and Big Sur (south of Monterey Bay) 

(Figure III.7c). Pacifc herring comprised the greatest proportion of catch in trawl samples in trawl samples 

in Canadian waters, and to a lesser extent in nearshore trawls between the Cape Flattery and the Columbia 

River (Figure III.7c). Anchovy were predominantly found in trawls conducted between Fort Bragg and 

Monterey, between Morro Bay and Point Conception, and near San Diego (Figure III.7c). The only trawl 

samples that contained sardine were collected near Newport, OR, Monterey, and San Diego. Overall, the 

158 trawls captured a combined 3512 kg of CPS (442 kg sardine, 88 kg anchovy, 1957 kg jack mackerel, 63 

kg Pacifc mackerel, and 961 kg Pacifc herring; Appendix D). 

IV. Disposition of Data 

Archived on the SWFSC data server are approximately 328 GB of raw EK60 data and 0.479 TB of raw ME70 

data. For more information, contact: David Demer (Southwest Fisheries Science Center, 8901 La Jolla Shores 

Drive, La Jolla, California, 92037, U.S.A.; phone: 858-546-5603; email: david.demer@noaa.gov). 

V. Acknowledgements 

We thank the crew members of FSV Shimada, as well as the scientists and technicians that participated in 

the sampling operations at sea. CPS-catch data were compiled by Bev Macewicz and CPS-egg data were 

compiled by Ed Weber. Critical reviews by Reviewer A and Gerard Dinardo improved this report. 

17 
18 

Figure III.7. Survey transects performed aboard Shimada overlaid with (a) the distribution of 38-kHz integrated backscattenmi-2; averaged over 2000-m distance intervals and from 5- to 70-m deep) ascribed to CPS; (b) anchovy-, jack mackerel-, a

(eggs m-3) from the CUFES; and (c) proportions of CPS species in trawl clusters (black points indicate trawls with no CPS
VI. Appendices 

Appendix A. Centerboard positions 

Transducer depths, associate with the centerboard position (retracted ~5-m, intermediate ~7-m, extended 

~9-m) during the SaKe 2015 aboard Shimada. 

Date Position Latitude Longitude 

06/20/2015 00:31 

06/26/2015 22:06 

07/08/2015 18:10 

07/13/2015 16:13 

07/16/2015 00:13 

Intermediate (7 m) 

Intermediate (7 m) 

Intermediate (7 m) 

Intermediate (7 m) 

Extended (9 m) 

32.63133 

34.95050 

37.75250 

39.15967 

40.45233 

-117.2837 

-121.6900 

-122.6672 

-123.9762 

-125.2527 

07/20/2015 02:56 

08/05/2015 15:25 

08/05/2015 18:07 

08/19/2015 12:34 

08/23/2015 15:15 

Intermediate (7 m) 

Retracted (5 m) 

Intermediate (7 m) 

Retracted (5 m) 

Retracted (5 m) 

41.78183 

44.62633 

44.59200 

47.62300 

47.62883 

-124.6800 

-124.0483 

-124.1232 

-122.3967 

-122.3808 

08/23/2015 19:33 

08/28/2015 14:16 

08/30/2015 20:42 

08/31/2015 22:01 

Intermediate (7 m) 

Extended (9 m) 

Extended (9 m) 

Intermediate (7 m) 

47.84433 

49.78533 

51.45283 

51.43833 

-122.4570 

-127.8182 

-130.4925 

-128.2955 

19 









Appendix B. Impedance measurements 

Transducer impedance magnitude (|Z|), phase (), conductance (G), susceptance (B), resistance (R), and 

reactance (X) measured at the operational frequencies with the transducer quadrants placed in parallel. 

Frequency (kHz) 

Measurement Units 18 38 70 120 200 

|Z|

 

G 

B 

R 

X 

deg 

mS 

mS 

17.66 

-10.75 

55.64 

10.56 

17.35 

-3.29 

18.19 

6.88 

54.59 

-6.59 

18.06 

2.18 

23.92 

-1.03 

41.75 

0.71 

23.89 

-0.51 

20.65 

14.21 

46.94 

-11.88 

20.02 

5.07 

24.72 

-4.31 

40.35 

3.04 

24.65 

-1.86 

20 
Appendix C. CTD and UCTD sample summary 

Times and locations of conductivity and temperature versus depth measurements while on station (CTD) 

and underway (UCTD). 

Date Type Latitude Longitude 

06/20/2015 03:19 

06/21/2015 03:28 

06/22/2015 03:28 

06/22/2015 17:24 

06/22/2015 18:09 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

32.80517 

33.24000 

33.57367 

33.86767 

33.86033 

-117.6333 

-117.5455 

-118.4302 

-118.6233 

-118.6337 

06/22/2015 18:37 

06/22/2015 19:17 

06/23/2015 00:23 

06/24/2015 03:21 

06/25/2015 03:06 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

33.86400 

33.85483 

33.76717 

34.18700 

34.61700 

-118.6288 

-118.6488 

-118.8245 

-120.3518 

-120.7085 

06/25/2015 13:49 

06/25/2015 14:47 

06/25/2015 16:16 

06/25/2015 19:29 

06/25/2015 21:24 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

34.61717 

34.61833 

34.61833 

34.62200 

34.61867 

-120.8127 

-120.8340 

-120.9513 

-121.4190 

-121.6188 

06/26/2015 03:37 

06/27/2015 03:38 

06/28/2015 03:44 

06/28/2015 04:57 

06/28/2015 13:40 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

34.95467 

35.28533 

35.95000 

35.94933 

35.94783 

-120.9392 

-121.1072 

-121.8707 

-121.8913 

-121.7978 

06/28/2015 15:19 

06/28/2015 16:29 

06/28/2015 17:05 

06/29/2015 03:46 

06/30/2015 03:48 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

35.95567 

35.94750 

35.95200 

36.25067 

36.70183 

-121.5945 

-121.5330 

-121.5238 

-122.3573 

-122.5233 

07/01/2015 03:56 

07/01/2015 14:04 

07/01/2015 15:57 

07/02/2015 03:46 

07/02/2015 23:54 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

36.95167 

36.95167 

36.95083 

37.45017 

38.11817 

-122.3500 

-122.3740 

-122.5783 

-122.8038 

-123.0097 

07/03/2015 01:49 

07/03/2015 03:19 

07/03/2015 13:35 

07/03/2015 15:01 

07/03/2015 15:58 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

38.11817 

38.11950 

38.11800 

38.11850 

38.11883 

-123.3238 

-123.4808 

-123.5135 

-123.5723 

-123.6050 

07/09/2015 03:47 

07/09/2015 19:33 

07/09/2015 21:50 

07/09/2015 22:20 

07/09/2015 23:22 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

36.95300 

37.20133 

37.20133 

37.20100 

37.20117 

-122.3645 

-122.6448 

-122.8450 

-122.9493 

-123.1605 

07/10/2015 02:25 

07/10/2015 04:04 

07/10/2015 13:27 

07/10/2015 14:25 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

37.44983 

37.44817 

37.45083 

37.45067 

-123.0170 

-122.8350 

-122.7032 

-122.5133 

21 
(continued)

Date Type Latitude Longitude 

07/10/2015 22:09 UCTD Cast 37.78433 -123.2892 

07/11/2015 01:14 

07/11/2015 02:13 

07/11/2015 05:48 

07/11/2015 13:08 

07/11/2015 14:05 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

37.78483 

37.78400 

37.77767 

38.11767 

38.11750 

-123.0735 

-122.8648 

-123.2010 

-122.9853 

-123.1983 

07/11/2015 15:10 

07/11/2015 22:13 

07/11/2015 23:52 

07/12/2015 04:31 

07/12/2015 13:15 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

38.11683 

38.45083 

38.45167 

38.45200 

38.45117 

-123.4162 

-123.8468 

-123.6395 

-123.4970 

-123.3205 

07/12/2015 17:43 

07/12/2015 17:43 

07/12/2015 18:43 

07/12/2015 19:45 

07/13/2015 02:26 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

38.78417 

38.78417 

38.78417 

38.78417 

39.11733 

-123.6653 

-123.6658 

-123.8813 

-124.0962 

-123.8067 

07/13/2015 02:39 

07/13/2015 03:20 

07/13/2015 04:04 

07/13/2015 13:47 

07/13/2015 18:13 

UCTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

39.11733 

39.11850 

39.11783 

39.12017 

39.10167 

-123.8475 

-123.9363 

-123.9722 

-124.0185 

-124.2320 

07/13/2015 22:37 

07/13/2015 23:37 

07/14/2015 05:18 

07/14/2015 13:41 

07/14/2015 14:11 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

39.45000 

39.44967 

39.44950 

39.78333 

39.78383 

-124.4357 

-124.2238 

-124.0125 

-124.0092 

-124.1170 

07/15/2015 03:31 

07/15/2015 13:15 

07/15/2015 13:47 

07/15/2015 17:56 

07/15/2015 18:33 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

CTD Cast 

40.11867 

40.11733 

40.11767 

40.45017 

40.45050 

-124.4253 

-124.3870 

-124.2732 

-124.6088 

-124.6198 

07/15/2015 19:15 

07/15/2015 21:37 

07/16/2015 04:09 

07/16/2015 15:37 

07/16/2015 19:18 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

40.45167 

40.44967 

40.63017 

40.78333 

40.78483 

-124.6292 

-124.8515 

-124.7198 

-124.3238 

-124.5395 

07/17/2015 22:26 

07/18/2015 02:14 

07/18/2015 13:46 

07/18/2015 14:25 

07/18/2015 15:33 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

CTD Cast 

41.11933 

41.44950 

41.45083 

41.45067 

41.45567 

-124.5255 

-124.3687 

-124.2062 

-124.3063 

-124.4617 

07/18/2015 16:26 

07/18/2015 16:26 

07/18/2015 17:27 

07/18/2015 19:21 

07/18/2015 23:29 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

41.45767 

41.45783 

41.45583 

41.45883 

41.45017 

-124.5018 

-124.5018 

-124.5163 

-124.5838 

-124.7472 

22 
(continued)

Date Type Latitude Longitude 

07/19/2015 01:13 

07/19/2015 03:59 

07/19/2015 13:44 

07/19/2015 18:02 

07/19/2015 19:08 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

41.45183 

41.78533 

41.78367 

41.78367 

41.78483 

-125.0148 

-125.1330 

-124.9940 

-124.7697 

-124.5447 

07/20/2015 03:10 

07/20/2015 13:20 

07/20/2015 16:40 

07/21/2015 05:03 

07/21/2015 14:08 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

41.78067 

42.11800 

42.11683 

42.34700 

42.45083 

-124.6832 

-124.4347 

-124.6603 

-124.8092 

-124.6067 

07/21/2015 14:57 

07/21/2015 15:29 

07/21/2015 16:09 

07/22/2015 00:18 

07/22/2015 03:12 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

42.45483 

42.45267 

42.45350 

42.45283 

42.45183 

-124.7417 

-124.7825 

-124.8328 

-125.0575 

-125.5720 

07/22/2015 20:52 

07/22/2015 21:55 

07/22/2015 23:38 

07/22/2015 23:38 

07/23/2015 00:08 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

42.78400 

42.78383 

42.78450 

42.78450 

42.78400 

-125.3458 

-125.1230 

-124.8932 

-124.8927 

-124.7837 

07/23/2015 03:32 

07/23/2015 04:30 

07/23/2015 13:45 

07/23/2015 16:21 

07/23/2015 17:25 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

43.11750 

43.11467 

43.11750 

43.11750 

43.11733 

-124.5527 

-124.7192 

-124.7818 

-124.9007 

-125.1282 

07/24/2015 01:50 

07/24/2015 02:52 

07/24/2015 03:22 

07/24/2015 04:04 

07/24/2015 21:34 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

43.44950 

43.45233 

43.45067 

43.45350 

43.45050 

-124.9518 

-124.7295 

-124.6148 

-124.5098 

-124.3803 

07/25/2015 00:27 

07/25/2015 01:30 

07/25/2015 02:22 

07/25/2015 03:32 

07/25/2015 18:54 

UCTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

43.78300 

43.78667 

43.78500 

43.78550 

43.78500 

-124.3200 

-124.5187 

-124.6203 

-124.7783 

-125.0133 

08/05/2015 21:45 

08/05/2015 22:50 

08/05/2015 23:48 

08/06/2015 01:49 

08/06/2015 03:55 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

44.11783 

44.11750 

44.11733 

44.11700 

44.19950 

-124.3140 

-124.5627 

-124.7758 

-125.0058 

-124.8895 

08/06/2015 18:14 

08/06/2015 19:18 

08/06/2015 20:19 

08/06/2015 20:34 

08/06/2015 22:32 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

44.23283 

44.29883 

44.36883 

44.38533 

44.45117 

-124.7802 

-124.5753 

-124.3648 

-124.3150 

-124.3432 

08/06/2015 23:37 UCTD Cast 44.45100 -124.5823 

23 
(continued)

Date Type Latitude Longitude 

08/07/2015 00:37 

08/07/2015 04:10 

08/07/2015 13:26 

08/07/2015 17:37 

UCTD Cast 

CTD Cast 

UCTD Cast 

CTD Cast 

44.45050 

44.38833 

44.45067 

44.79000 

-124.8112 

-124.8827 

-124.9303 

-125.0795 

08/07/2015 18:47 

08/07/2015 19:45 

08/07/2015 20:48 

08/08/2015 01:21 

08/08/2015 06:58 

CTD Cast 

UCTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

44.78617 

44.78400 

44.78500 

44.78367 

44.78033 

-125.0170 

-124.9767 

-124.8725 

-124.6068 

-125.1080 

08/08/2015 14:02 

08/08/2015 15:59 

08/08/2015 18:59 

08/08/2015 20:03 

08/09/2015 01:19 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

44.78617 

44.78283 

45.11767 

45.11767 

45.11750 

-124.4468 

-124.1542 

-124.0725 

-124.3182 

-124.5397 

08/09/2015 01:50 

08/09/2015 02:23 

08/09/2015 04:05 

08/09/2015 14:16 

08/09/2015 18:40 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

45.11733 

45.11767 

45.11550 

45.36750 

45.36667 

-124.6553 

-124.7743 

-125.0868 

-124.8217 

-124.3913 

08/09/2015 22:42 

08/10/2015 01:52 

08/10/2015 02:24 

08/10/2015 02:57 

08/10/2015 03:57 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

45.61833 

45.61733 

45.61767 

45.61783 

45.61833 

-124.1700 

-124.4035 

-124.5257 

-124.6488 

-124.7665 

08/10/2015 15:07 

08/10/2015 18:03 

08/10/2015 18:34 

08/10/2015 19:02 

08/10/2015 20:04 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

45.67400 

45.69983 

45.73117 

45.75667 

45.81367 

-124.7490 

-124.6375 

-124.5278 

-124.4280 

-124.2027 

08/10/2015 20:18 

08/10/2015 21:43 

08/10/2015 22:56 

08/10/2015 23:47 

08/11/2015 00:42 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

45.82683 

45.86750 

45.87617 

45.86800 

45.86800 

-124.1507 

-124.1742 

-124.4038 

-124.5322 

-124.6558 

08/11/2015 01:16 

08/11/2015 13:41 

08/11/2015 16:01 

08/11/2015 18:59 

08/11/2015 20:01 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

45.86767 

45.86950 

45.86717 

46.11683 

46.11767 

-124.7245 

-124.7728 

-125.0143 

-124.9748 

-124.7330 

08/12/2015 00:34 

08/12/2015 01:37 

08/12/2015 02:37 

08/12/2015 04:09 

08/12/2015 14:13 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

46.11750 

46.11750 

46.11667 

46.07217 

46.36733 

-124.6175 

-124.3712 

-124.1335 

-124.2565 

-124.3817 

08/12/2015 18:41 

08/12/2015 22:15 

08/12/2015 23:27 

UCTD Cast 

UCTD Cast 

UCTD Cast 

46.36733 

46.61650 

46.61683 

-124.8628 

-124.9413 

-124.6483 

24 
(continued)

Date Type Latitude Longitude 

08/13/2015 05:09 

08/13/2015 13:28 

CTD Cast 

UCTD Cast 

46.68533 

46.86750 

-124.4877 

-124.3245 

08/13/2015 14:30 

08/13/2015 15:27 

08/13/2015 18:49 

08/13/2015 20:57 

08/13/2015 21:50 

UCTD Cast 

CTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

46.86650 

46.86517 

46.86817 

46.87083 

46.87733 

-124.5698 

-124.7623 

-124.9345 

-125.1698 

-125.2277 

08/13/2015 22:52 

08/14/2015 01:54 

08/14/2015 02:55 

08/14/2015 04:37 

08/14/2015 14:06 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

46.93683 

46.96600 

47.02317 

47.03983 

47.11750 

-124.9927 

-124.8838 

-124.6552 

-124.7140 

-124.9925 

08/14/2015 15:07 

08/14/2015 15:21 

08/14/2015 18:22 

08/14/2015 22:19 

08/15/2015 01:13 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

47.11800 

47.11717 

47.11800 

47.36717 

47.36750 

-124.7492 

-124.6927 

-124.5035 

-124.7923 

-125.0380 

08/15/2015 02:12 

08/15/2015 03:58 

08/15/2015 14:19 

08/15/2015 15:20 

08/15/2015 16:42 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

47.36717 

47.34200 

47.61733 

47.61733 

47.62183 

-125.2812 

-125.6118 

-125.8703 

-125.6250 

-125.3822 

08/15/2015 18:21 

08/15/2015 19:04 

08/16/2015 01:26 

08/16/2015 02:29 

08/16/2015 05:25 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

CTD Cast 

47.62117 

47.61833 

47.61850 

47.61800 

47.54650 

-125.1302 

-125.0913 

-124.9637 

-124.7548 

-124.9617 

08/16/2015 14:55 

08/16/2015 18:21 

08/17/2015 01:16 

08/17/2015 02:55 

08/17/2015 13:57 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

47.86583 

47.86767 

47.86750 

47.86500 

48.11733 

-124.9138 

-125.2253 

-125.4715 

-125.8177 

-126.0315 

08/17/2015 14:58 

08/17/2015 17:54 

08/17/2015 19:16 

08/17/2015 20:16 

08/17/2015 21:17 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

48.11600 

48.11733 

48.11800 

48.11817 

48.11717 

-125.7823 

-125.6562 

-125.4083 

-125.1573 

-124.9097 

08/18/2015 04:04 

08/24/2015 05:44 

08/24/2015 14:18 

08/24/2015 15:13 

08/24/2015 18:18 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

48.05033 

48.41833 

48.45067 

48.45117 

48.45083 

-124.8952 

-124.8175 

-124.9480 

-125.1822 

-125.4363 

08/24/2015 19:19 

08/24/2015 20:19 

08/24/2015 20:49 

08/24/2015 23:45 

08/25/2015 02:03 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

48.45100 

48.45083 

48.45100 

48.45117 

48.48733 

-125.6908 

-125.9427 

-126.0692 

-126.2058 

-126.4357 

25 
(continued)

Date Type Latitude Longitude 

08/25/2015 03:03 

08/25/2015 03:47 

08/25/2015 17:46 

08/25/2015 18:56 

08/25/2015 22:20 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

48.54617 

48.56200 

48.63250 

48.69433 

48.74750 

-126.1955 

-126.1102 

-125.8517 

-125.5915 

-125.3800 

08/26/2015 00:18 

08/26/2015 02:17 

08/26/2015 03:40 

08/26/2015 14:47 

08/26/2015 22:27 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

48.78350 

48.78383 

48.78417 

48.78400 

49.11767 

-125.5692 

-126.0705 

-126.3278 

-126.5905 

-126.9217 

08/27/2015 01:59 

08/27/2015 04:41 

08/27/2015 18:28 

08/27/2015 19:49 

08/27/2015 21:07 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

49.11800 

49.13250 

49.45117 

49.45117 

49.45200 

-126.4898 

-126.4353 

-126.6123 

-126.8822 

-127.1247 

08/27/2015 22:49 

08/28/2015 02:12 

08/28/2015 03:29 

08/28/2015 13:53 

08/28/2015 14:53 

CTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

49.45233 

49.44983 

49.45550 

49.78467 

49.78417 

-127.2515 

-127.5148 

-127.6865 

-127.9147 

-127.6590 

08/28/2015 23:28 

08/29/2015 03:51 

08/29/2015 15:23 

08/29/2015 16:23 

08/29/2015 16:25 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

50.11800 

50.12150 

50.11767 

50.11800 

50.11817 

-128.0463 

-128.1455 

-128.3058 

-128.5657 

-128.5728 

08/29/2015 18:03 

08/29/2015 19:04 

08/29/2015 20:07 

08/30/2015 00:49 

08/30/2015 01:22 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

UCTD Cast 

50.16100 

50.25583 

50.35167 

50.45083 

50.45050 

-128.7613 

-128.5427 

-128.3180 

-128.4162 

-128.5557 

08/30/2015 02:19 

08/30/2015 03:39 

08/31/2015 03:41 

08/31/2015 17:04 

08/31/2015 18:19 

UCTD Cast 

CTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

50.45017 

50.44617 

51.44917 

51.45100 

51.45300 

-128.8023 

-129.0135 

-128.8407 

-128.6360 

-128.2950 

08/31/2015 18:21 

09/01/2015 05:31 

09/01/2015 19:32 

09/01/2015 21:10 

09/02/2015 03:42 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

51.45300 

52.62533 

52.61750 

52.61850 

52.95017 

-128.2863 

-129.6703 

-130.4367 

-130.8220 

-130.4167 

09/02/2015 14:47 

09/02/2015 17:52 

09/02/2015 22:49 

09/03/2015 04:12 

09/03/2015 17:14 

UCTD Cast 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

52.95167 

52.95150 

53.28350 

53.61550 

54.39950 

-130.1940 

-129.9282 

-130.7207 

-130.7632 

-131.1478 

09/03/2015 20:23 UCTD Cast 54.53933 -131.1473 

26 
(continued)

Date Type Latitude Longitude 

09/03/2015 21:16 

09/04/2015 04:18 

09/04/2015 15:04 

09/04/2015 17:45 

UCTD Cast 

CTD Cast 

UCTD Cast 

UCTD Cast 

54.68317 

54.28750 

54.28433 

54.28417 

-131.1483 

-132.8650 

-133.1537 

-133.3888 

09/04/2015 21:22 

09/04/2015 22:04 

09/05/2015 04:17 

09/05/2015 15:07 

09/05/2015 19:58 

UCTD Cast 

UCTD Cast 

CTD Cast 

UCTD Cast 

CTD Cast 

54.28417 

54.28350 

53.95267 

53.95083 

53.61800 

-133.6498 

-133.8488 

-133.9878 

-133.8012 

-133.1940 

09/05/2015 20:19 

09/06/2015 04:08 

09/06/2015 15:40 

09/06/2015 23:14 

09/07/2015 03:36 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

CTD Cast 

53.61817 

53.28067 

53.28533 

52.94717 

52.95217 

-133.1913 

-133.3682 

-133.0753 

-132.5023 

-132.9615 

09/07/2015 18:13 

09/08/2015 00:03 

CTD Cast 

CTD Cast 

52.28550 

51.94500 

-131.5523 

-131.2625 

27 
28 

Appendix D. Trawl sample summary Date, time, and location at the start of trawling (i.e., at net equilibrium), and biomasses (kg) of CPS species collected in eaceach trawl set was nominally 45 min. 

Haul Date Latitude Longitude Anchovy Sardine P. mackerel J. mackerel P. herring 

1 06/19/2015 21:56 2 06/20/2015 00:35 3 06/20/2015 02:49 4 06/20/2015 21:25 5 06/20/2015 23:24 

32.847 32.893 32.945 33.249 33.272 

-117.553 -117.465 -117.392 -117.531 -117.558 

0.157 0.010 0.036 2.906 

0.008 

0.058 0.007 

6 06/21/2015 01:32 7 06/21/2015 21:10 8 06/21/2015 23:31 9 06/22/2015 01:34 

10 06/22/2015 20:48 

33.240 33.580 33.546 33.544 33.600 

-117.569 -118.407 -118.408 -118.445 -119.303 

9.057 0.006 

0.048 0.071 

11 12 13 14 15 

06/22/2015 22:56 06/23/2015 01:21 06/23/2015 21:13 06/23/2015 23:40 06/24/2015 02:04 

33.650 33.710 34.215 34.211 34.197 

-119.444 -119.522 -120.274 -120.237 -120.251 

2.366 0.459 

20.552 

0.003 0.004 

16 17 18 19 20 

06/24/2015 20:27 06/24/2015 22:43 06/25/2015 01:20 06/25/2015 21:13 06/25/2015 23:29 

34.644 34.649 34.732 34.961 35.022 

-120.746 -120.861 -120.760 -120.996 -121.040 

0.000 0.122 

30.669 

0.065 

1.280 

21 22 23 24 25 

06/26/2015 01:54 06/26/2015 21:10 06/26/2015 23:25 06/27/2015 01:42 06/27/2015 21:18 

34.926 35.280 35.362 35.273 35.954 

-121.034 -121.142 -121.058 -121.052 -121.904 

0.122 0.001 

0.021 0.014 

133.400 

26 27 28 29 30 

06/27/2015 23:38 06/28/2015 01:54 06/28/2015 21:26 06/28/2015 23:55 06/29/2015 02:13 

35.999 35.894 36.245 36.382 36.275 

-122.009 -121.951 -122.377 -122.316 -122.236 

0.014 0.002 0.109 0.001 

0.008 0.002 

0.006 0.002 1.443 0.122 0.020 
29 

(continued)

Haul Date Latitude Longitude Anchovy Sardine P. mackerel J. mackerel P. herring 

31 32 33 34 35 

06/29/2015 21:07 06/29/2015 23:33 06/30/2015 01:57 06/30/2015 21:35 06/30/2015 23:58 

36.710 36.763 36.639 36.953 37.022 

-122.509 -122.388 -122.389 -122.326 -122.312 

0.004 0.000 

0.198 0.122 

36 37 38 39 40 

07/01/2015 02:21 07/01/2015 21:02 07/01/2015 23:23 07/02/2015 02:03 07/02/2015 21:09 

36.906 37.443 37.535 37.395 38.124 

-122.295 -122.823 -122.784 -122.774 -123.445 

0.004 

41 42 43 44 45 

07/02/2015 23:28 07/08/2015 21:52 07/09/2015 00:23 07/09/2015 03:00 07/09/2015 21:44 

38.218 36.959 37.032 36.922 37.450 

-123.522 -122.389 -122.413 -122.428 -122.879 

3.043 

17.800 

0.030 0.377 

0.020 1.162 

46 47 48 49 50 

07/10/2015 00:14 07/10/2015 02:40 07/10/2015 23:23 07/11/2015 01:37 07/11/2015 22:11 

37.373 37.479 37.817 37.934 38.526 

-122.945 -122.969 -123.248 -123.230 -123.595 

0.016 0.020 0.057 

0.005 0.001 0.002 

0.014 

51 52 53 54 55 

07/12/2015 00:19 07/12/2015 02:18 07/12/2015 23:40 07/13/2015 01:53 07/13/2015 23:06 

38.564 38.506 38.796 38.903 39.447 

-123.748 -123.660 -123.784 -123.896 -124.113 

0.051 0.004 0.003 

56 57 58 59 60 

07/14/2015 01:22 07/15/2015 22:02 07/16/2015 00:20 07/16/2015 02:36 07/17/2015 20:52 

39.553 40.555 40.652 40.630 41.564 

-124.035 -124.663 -124.678 -124.669 -124.380 

0.001 0.000 

1.153 0.035 

49.700 

2.783 

61 62 63 

07/17/2015 23:32 07/18/2015 02:21 07/18/2015 22:00 

41.466 41.372 41.762 

-124.490 -124.346 -125.043 

46.959 16.380 
30 

(continued)

Haul Date Latitude Longitude Anchovy Sardine P. mackerel J. mackerel P. herring 

64 65 

07/19/2015 00:03 07/19/2015 03:21 

41.816 41.711 

-125.161 -125.117 

66 67 68 69 70 

07/19/2015 21:00 07/19/2015 23:08 07/20/2015 01:50 07/20/2015 22:31 07/21/2015 02:25 

41.776 41.812 41.946 42.347 42.339 

-124.704 -124.545 -124.497 -124.832 -124.829 

0.001 

1.051 14.014 

32.750 

746.871 119.219 

71 72 73 74 75 

07/21/2015 23:43 07/22/2015 02:23 07/22/2015 22:12 07/23/2015 00:48 07/23/2015 03:12 

42.471 42.428 43.135 43.218 43.116 

-124.856 -124.927 -124.766 -124.690 -124.609 

0.002 

1.470 2.031 

30.673 

1.562 

18.050 95.908 

76 77 78 79 80 

07/23/2015 21:40 07/24/2015 00:03 07/24/2015 02:27 07/24/2015 21:27 07/25/2015 00:37 

43.459 43.503 43.451 43.805 43.848 

-124.554 -124.558 -124.529 -124.842 -124.524 

0.002 0.004 0.002 

0.457 2.410 15.452 

4.826 8.400 9.714 6.367 

1.400 0.100 

157.550 

81 82 83 85 86 

07/25/2015 03:07 07/25/2015 23:04 07/26/2015 00:21 08/06/2015 00:57 08/06/2015 03:16 

43.786 44.259 44.352 44.097 44.110 

-124.496 -124.787 -124.801 -124.703 -124.856 

0.002 

4.782 

428.091 

6.449 

24.047 

10.600 62.180 

9.887 

0.098 6.300 

26.700 

87 88 89 90 91 

08/06/2015 22:28 08/07/2015 01:03 08/07/2015 03:02 08/07/2015 21:40 08/08/2015 03:27 

44.439 44.423 44.547 44.725 44.786 

-124.719 -124.885 -124.897 -125.078 -124.446 

0.136 0.102 158.486 

3.400 

14.300 

1.500 

2.500 0.150 

92 93 94 95 96 

08/08/2015 21:46 08/09/2015 00:16 08/09/2015 03:09 08/09/2015 23:07 08/10/2015 01:47 

45.127 45.257 45.368 45.625 45.698 

-125.135 -125.069 -124.823 -124.307 -124.443 

0.032 1.730 

67.600 25.850 43.579 0.187 

97 08/10/2015 21:43 45.933 -124.764 64.850 
31 

(continued)

Haul Date Latitude Longitude Anchovy Sardine P. mackerel J. mackerel P. herring 

98 99 

100 101 

08/11/2015 00:48 08/11/2015 03:08 08/11/2015 21:23 08/11/2015 23:27 

45.878 45.976 46.105 46.246 

-124.533 -124.581 -124.290 -124.474 0.066 

52.050 

3.450 

13.029 

7.850 0.430 1.900 1.750 

102 103 104 105 106 

08/12/2015 01:51 08/12/2015 22:34 08/13/2015 01:17 08/13/2015 22:02 08/14/2015 00:29 

46.334 46.741 46.833 47.088 47.127 

-124.307 -124.541 -124.435 -124.754 -125.013 

0.026 0.140 0.026 

3.462 0.882 

19.500 14.900 

8.400 0.100 

107 108 109 111 112 

08/14/2015 03:11 08/14/2015 21:31 08/14/2015 23:44 08/15/2015 22:59 08/16/2015 01:09 

47.084 47.366 47.528 47.574 47.742 

-125.173 -125.664 -125.754 -125.007 -124.965 0.201 

2.293 0.004 

0.200 

113 114 115 116 117 

08/16/2015 03:16 08/16/2015 20:50 08/16/2015 23:11 08/17/2015 01:39 08/17/2015 21:17 

47.857 47.957 48.139 48.093 48.082 

-124.830 -125.888 -126.033 -126.177 -124.928 

0.198 

48.550 

0.450 1.750 

118 119 120 121 122 

08/17/2015 23:09 08/18/2015 01:48 08/24/2015 00:02 08/24/2015 02:38 08/24/2015 21:30 

48.145 48.042 48.379 48.296 48.570 

-124.936 -125.269 -124.862 -124.926 -126.175 

0.036 0.212 

16.100 

15.550 

0.044 

13.200 

123 124 125 126 127 

08/25/2015 00:05 08/25/2015 02:33 08/25/2015 21:25 08/25/2015 23:44 08/26/2015 03:02 

48.519 48.485 48.836 48.752 48.845 

-126.148 -126.327 -126.384 -126.274 -126.133 

0.001 0.000 0.001 0.065 

128 129 130 131 

08/26/2015 22:02 08/27/2015 00:18 08/27/2015 02:50 08/27/2015 21:43 

49.182 49.069 49.047 49.581 

-126.501 -126.602 -126.404 -127.545 

0.100 

25.910 

31.850 

561.350 

6.400 
32 

(continued)

Haul Date Latitude Longitude Anchovy Sardine P. mackerel J. mackerel P. herring 

132 08/28/2015 00:49 49.663 -127.730 

133 134 135 136 137 

08/28/2015 03:13 08/28/2015 21:11 08/28/2015 23:30 08/29/2015 01:58 08/29/2015 21:07 

49.759 50.079 50.102 50.164 50.393 

-127.852 -128.156 -128.023 -128.148 -129.026 

1.700 

138 139 140 141 142 

08/30/2015 00:14 08/30/2015 03:15 08/30/2015 21:09 08/30/2015 23:26 08/31/2015 01:43 

50.362 50.516 51.409 51.403 51.371 

-128.797 -128.923 -128.966 -128.837 -128.691 

0.600 0.350 

143 144 145 146 147 

08/31/2015 22:56 09/01/2015 01:16 09/01/2015 03:22 09/01/2015 21:08 09/01/2015 23:12 

52.593 52.680 52.583 53.015 52.944 

-129.768 -129.716 -129.618 -130.335 -130.261 

2.200 8.750 

18.550 

0.250 0.092 

148 149 150 151 152 

09/02/2015 01:23 09/03/2015 22:23 09/04/2015 01:14 09/04/2015 03:26 09/04/2015 21:43 

52.867 54.241 54.400 54.310 53.886 

-130.301 -132.730 -132.698 -132.667 -133.942 

48.550 

1.350 

153 154 155 156 157 

09/04/2015 23:58 09/05/2015 02:36 09/05/2015 21:41 09/06/2015 00:40 09/06/2015 03:08 

53.970 54.004 53.278 53.249 53.378 

-133.839 -134.079 -133.473 -133.193 -133.325 

158 159 160 

09/06/2015 21:20 09/06/2015 23:31 09/07/2015 01:48 

52.939 52.895 52.824 

-132.943 -132.795 -132.617 
VII. References 

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33