Acoustic Target Strength Measurements for Biomass Estimation of Aquaculture Fish, Redlip Mullet (Chelon haematocheilus)

Redlip mullet (Chelon haematocheilus) is distributed in coastal waters of the North-Western Pacific Ocean and is a cultured fish in Korea. A hydroacoustic technique constitutes a useful method to assess the biomass and spatial distribution of mullet in sea cages or in coastal waters, and acoustic target strength (TS) information of the target fish is an essential parameter in using this method. In this study, ex situ TS measurements of 16 live mullets were made in an aquaculture sea cage in Korea. The split-beam scientific echo-sounder used for measurements was comprised of 38, 120, 200, and 420 kHz frequencies. An underwater video camera was simultaneously used to observe the mullets’ behavior during the TS measurements. The mullet TS data was analyzed from a wide range of total fish length (FL: 14.3–40.3 cm). As results for all frequencies, the frequency dependence of the mean TS values were relatively low, and the difference in mean TS was within 2.5 dB. When the slope of the least-squares regression line was forced to 20 into the TS equation, the resulting value for the constant term (b20) at each frequency was −67.0 dB, −68.3 dB, −66.3 dB, and −68.5 dB, respectively. The data tended to be frequency dependent. Additionally, the maximum TS appeared between tilt angles of 0° and 10°. These results indicate that TS measurements can be applied to estimate the biomass of the mullet in sea cages or in coastal waters.

[1]  M. Kim,et al.  An outbreak of Lactococcus garvieae Infection in Cage-cultured Red Lip Mullet Chelon haematocheilus with Green Liver Syndrome , 2015 .

[2]  SangHoon Lee,et al.  Ex situ echo sounder target strengths of ice krill Euphausia crystallorophias , 2015, Chinese Journal of Oceanology and Limnology.

[3]  P. Economidis,et al.  Sexual maturity of the alien redlip mullet, Liza haematocheilus (Temminck & Schlegel, 1845) in north Aegean Sea (Greece) , 2010 .

[4]  Sungho Cho,et al.  Ex situ target-strength measurements of Japanese anchovy (Engraulis japonicus) in the coastal Northwest Pacific , 2009 .

[5]  K. Boswell,et al.  Side-aspect target-strength measurements of bay anchovy (Anchoa mitchilli) and Gulf menhaden (Brevoortia patronus) derived from ex situ experiments , 2008 .

[6]  J. J. Day,et al.  Fishes of the World, 4th Edition , 2006 .

[7]  P. Brehmer,et al.  Fisheries Acoustics: Theory and Practice, 2nd edn , 2006 .

[8]  A. Brierley,et al.  Setting a precautionary catch limit for Antarctic krill , 2002 .

[9]  Paul G. Fernandes,et al.  A consistent approach to definitions and symbols in fisheries acoustics , 2002 .

[10]  J. Nielsen,et al.  Hydroacoustic ex situ target strength measurements on juvenile cod (Gadus morhua L.) , 1999 .

[11]  W. Tzeng,et al.  Redescription of Redlip Mullet Chelon haema- tocheilus (Pisces: Mugilidae) with a Key to Mugilid Fishes in Taiwan , 1999 .

[12]  Kohji Iida,et al.  Depth dependence of target strength of live kokanee salmon in accordance with Boyle's law , 1996 .

[13]  I. Hampton.  Acoustic and egg-production estimates of South African anchovy biomass over a decade: comparisons, accuracy, and utility , 1996 .

[14]  John K. Horne,et al.  Acoustic models of fish: The Atlantic cod (Gadus morhua) , 1994 .

[15]  R. Hewitt,et al.  Dispersion and abundance of Antarctic krill in the vicinity of Elephant Island in the 1992 austral summer , 1993 .

[16]  K. Foote.  Fish target strengths for use in echo integrator surveys , 1987 .

[17]  W. Eschmeyer,et al.  A field guide to Pacific Coast fishes of North America , 1983 .