Swimming speed measurement of Pacific saury (Cololabis saira) using Acoustic Doppler Current Profiler

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,

(Acoustic Doppler Current Profilers : ADCPs, ADCP)

J. Kor. Soc. Fish. Tech., 46 (2), 165 172, 2010 DOI:10.3796/KSFT.2010.46.2.165

Swimming speed measurement of Pacific saury (Cololabis saira) using Acoustic Doppler Current Profiler

Kyoung-Hoon LEE*, Dae-Jae LEE¹, Hyung-Seok KIM¹and Seong-Wook PARK

Fisheries System Engineering Division, National Fisheries Research & Development Institute, Busan 619-705, Korea

1Division of Marine Production System Management, Pukyong National University, Busan, 608-737, Korea

This study was performed to estimate the swimming velocity of Pacific saury (Cololabis saira) migrated offshore Funka Bay of Hokkaido using an acoustic Doppler current profiler (OceanSurveyor, RDI, 153.6kHz) established in T/S Ushio-maru of Hokkaido University, in September 27, 2003. The ADCP s doppler shift revealed as the raw data that the maximum swimming velocity was measured 163.0cm/s, and its horizontal swimming speed and direction were 72.4 24.1 cm/s, 160.1 22.3 while the surrounding current speed and direction were 19.6 8.4cm/s, 328.1 45.3 . To calculate the actual swimming speed of Pacific saury in each bins, comparisons for each stratified bins must be made between the mean surrounding current velocity vectors, measured for each stratified bin, and its mean swimming velocity vectors, assumed by reference (threshold 70dB) and 5dB margin among four beams of ADCP. As a result, the actual averaged swimming velocity was 88.6cm/s and the averaged 3-D swimming velocity was 91.3cm/s using the 3-D velocity vector, respectively.

Keywords: Acoustic Doppler Current Profiler, Pacific saury, swimming speed, 3-D velocity vector

*Corresponding author: [email protected], Tel:82-51-720-2571, Fax:82-51-720-2586

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Fig. 1. 1 min-averaged current information at the depth of 20m measured by shipboard ADCP installed on T/S Ushio-maru in offshore Funka bay.

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Pitch (tilt 1) ; set to 0.000deg.

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Fig. 3. Vertical distributions of the averaged SV, horizontal current speed and current direction measured by shipboard ADCP after net sampling. The averaged SV was derived for 30 seconds.

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Fig. 5. Histograms for fish moving speed (a) and direction (b) estimated on the basis of MVBS thresholds ( 70dB) and fish-to-background thresholds of 5dB, and surrounding horizontal current speed (c) and direction (d).

Fig. 4. Depth distribution of measured horizontal speed (a), and MVBS (b) calculated from echo intensity in 30 sec- averaged value which is measured using ADCP 153.6 kHz for fish school distributed in sound scattering layer.

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Horizontal speed (cm/s) Horizontal direction (deg.)

Frequency (%)

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N 577 Avg. 160.1 S.D. 22.3

N 573 Avg. 19.6 cm/s S.D. 8.4 cm/s

N 573 Avg. 328.1 S.D. 45.3

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Deines, K.L., 1999. Backscatter estimation using broadband acoustic Doppler current profilers.

Proceedings of the IEEE Sixth Working Conference on Current Measurement, San Diego, pp. 5.

Demer, D.A., M. Barange and A.J. Boyd, 2000.

Measurements of three dimensional fish school velocities with an acoustic Doppler current profiler.

Fish. Res., 47, 201 214.

Dickson, K.A., J.M. Donley, C. Sepulveda and L.

Bhoopat, 2002. Effect of temperature on sustained swimming performance and swimming kinematics of the chub mackerel Scomber japonicus. J. of Exp.

Bio., 205, 969 980.

Holliday, D.V., 1974. Doppler structure in echoes from schools of pelagic fish. J. Acoust. Soc. Am., 55 (6), 1313 1322.

Plimpton, P.E., P.H. Freitag and M.J. McPhaden, 1997.

ADCP velocity errors from pelagic fish schooling around equatorial moorings. Journal of Atmospheric and Oceanic Technology, 14, 1212 1223.

RD Instruments, 1996a. Acoustic Doppler Current Profiler, Principles of Operation a Practical Primer.

RD Instruments, San Diego, California, USA, 51pp.

RD Instruments, 1996b. Field service technical paper 001 (FST 001) Broadband ADCP advanced principles of operation 01 October 1996. RD Instruments, San Diego, California, USA, pp. 15.

Zedel, L., T. Knutsen and R. Patro, 2003. Acoustic Doppler current profiler observations of herring movement. ICES J. Mar. Sci., 60, 846 859.

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