Hydroacoustic investigation on the distribution characteristics of the anchovy 
                                in the East Sea of Korea

                 Kang, MyoungHee & Yoon, Gab Dong(Pukyong Uni.)

     It  was analyzed  the biological  and acoustic  characteristics  of anchovy  shoal 
such as  spatial distribution, volume backscattering  strength and species  composition 
of trawling catch, by using a echo sounder(OSSIAN 1500) in the east sea of korea.
  1) In the site  A of Lat. 36!F55'N, Long. 129!F40'E, the anchovy  shoal of small to 
middle size with the horizontal range of 10!-25m and large size with that of 40!-50m 
were  distributed together.  However, in  b  of Lat.  35!F38'N, Long.  129!F40'E,  the 
anchovy shoal  was observed to be  mainly small size which  was about 78% of  the 
detected shoal. Another was that the anchovy shoal with  the vertical range of 2!-8m 
occupied about 68.6% in A and that of 6!-12m occupied about 42.5% in B.
  The cross sectional area and  its anchovy shoal proportion to the total in A  and B 
were found to be 10!-50m2, 64.5% and 20!-80m2, 66%, respectively.
  2) In A,  the backscattering strength of  -40.0!--28.0dB was analyzed about  63.0% 
of the detected fish shoal and that of -42.0!--38.0dB in B was analyzed about 41.4%.
  3)  Most  of   anchovy  shoal  was  concentrated  on   50!-100m  in  depth  with 
15.3!-18.5!I, 34.0!I34.3"6 in A and 14.2!-16.4!I, 34.1!-34.2"6 in B.
  4) Mean total  length(TL) and body weight(BW) of anchovy  in A were 9.9cm and 
4.4g, with  TL-BW relationship of  BW=0.0007TL3.85. In  B, mean TL  and BW were 
11.2cm, 8.7g, with TL-BW relationship of BW=0.0023TL3.38.