Combined Underwater Acoustic and Radar Instruments for Assessing Fish
Near Seabed and Mapping Seabed
A0067Henry Manik Marine Instrumentation Engineering Laboratory, Tokyo University of Fisheries
A0068Masahiko Furusawa Marine Instrumentation Engineering Laboratory, Tokyo University of Fisheries
Underwater acoustic and marine radar survey was conducted for
assessment of fish near seabed and for seabed mapping. For the
purpose, a high resolution underwater acoustic instrument (split beam
echo sounder), a ground penetrating radar, an oceanographic
measurement instrument were used around Seribu Island, Jakarta Bay.
Research vessel Mina Jaya (30 GT) and various marine research
instruments were employed during the survey. The result of this
research consists of distribution of fish target strength,
oceanographical condition distribution, bathymetric map, sea bottom
map and shallow subbottom profile.Fish near seabed has a target
strength value from ? 50 dB to ? 35 dB. Radar has a high resolution
for subbottom detection than acoustic method.