Studi tingkah laku migrasi ikan demersal berdasarkan data pemeruman

Abstract

Sounding data processing of Tarakan sea is aimed to discover migration behavior of demersal fish. The data were processed by using Myriax Echoview 4.8 and Microsoft Office Excel 2007. Data were processed are Nautical Area Scattering Coefficient (NASC), Volume Backscattering Strength (SV); fish school and seabed depth; height and length of fish school. Fishes in May, August and November are assumed as same varieties, based on similarty of height to length ratio. The biggest horizontal migration was found in August and the biggest vertical migration in November. Horizontal migration was occured from shallower to deeper depth, based on enlarged school shape that towards the deeper depth. Vertical migration in November is assumed as feeding migration, based on appearance of small pelagic objects

Pengolahan data pemeruman di Laut Tarakan bertujuan mengetahui tingkah laku migrasi gerombolan ikan demersal. Pengolahan data dilakukan menggunakan perangkat lunak Echoview 4.8 dan Ms. Exel 2007. Data pemeruman yang diolah adalah Nautical Area Scattering Coefficient (NASC), Volume Backscattering Strength (SV), kedalaman gerombolan ikan, kedalaman dasar laut, panjang gerombolan dan tebal gerombolan ikan. Diduga ikan yang terdapat di Laut Tarakan pada bulan Mei, Agustus dan November adalah sama, bedasarkan kemiripan karakteristik rasio tebal terhadap panjang gerombolan. Migrasi mendatar terbesar terjadi pada bulan Agustus dan migrasi menegak terbesar terjadi pada bulan November. Diduga migrasi mendatar terjadi dari perairan lebih dangkal ke perairan lebih dalam, berdasarkan bentuk gerombolan yang membesar ke arah perairan lebih dalam. Migrasi menegak pada bulan November diduga merupakan jenis migrasi untuk memperoleh makanan, berdasarkan kemunculan objek pelagis kecil.