ABSTRAKAnalisis migrasi vertikal zooplankton di Laut Banda telah dilakukan berdasarkan nilai hambur balik akustik yang diperoleh dari pengukuran pada tanggal 21-30 November 2013 menggunakan instrument akustik simrad EK 500 yang dipasang pada Kapal Riset Baruna Jaya VII. Hasil analisis menunjukan migrasi vertikal zooplankton di Laut Banda merupakan fungsi dari waktu dan konsentrasi klorofil. Agregasi zooplankton berada pada lapisan permukaan 0-25 meter untuk setiap waktu pengamatan, bersamaan dengan nilai konsentrasi khorofil yang tinggi yakni mencapai 2,1 mg/m 3 . Nilai volume hamburan balik akustik rerata pada strata kedalaman 0-25 meter adalah -84,31 dB, pada kedalaman 25-50 meter sebesar -82,02 dB dan pada kedalaman 50-75 meter sebesar -83,9 dB.Kata kunci: Volume hamburan, migrasi vertikal, zooplankton 25-50meters -82.02 dB and at a depth of 50-75 meters -83.9 dB. ABSTRACT Analysis of the vertical migration of zooplankton in the Banda

The study aims to analyze daily migration of zooplankton in Banda Sea and contribution of Calanoida to scattering volume. Applied method is exploratory description through direct survey toward zooplankton by using Baruna Jaya VII vessel as floating platform. The findings show that daily migration of zooplankton in surface layer occurs in every observation period, average value of scattering volume in stratified depth of 0-25 meter is -84.19 dB. For stratified depth of 25-50 meter, scattering volume reaches -81.81 dB. At 00:00-03:00, zooplankton is concentrated densely at three water layers by SV value of 84.25, -81.88, -83.9 dB. Zooplankton aggregation is always almost at surface layer of 0-25 meter at every observation time. Allegedly, oceanographic factor with high concentration value of chlorophyll a are the reason. Concentration value of chlorophyll a in this depth may reach 2.1 mg/m 3 . Calanoid contributes to value of scattering volume by regression formulation of Y=-8.93+0.01 Calanoida -0.001 Cyclopoida.

The study aims to analyze diurnal migration of zooplankton in Ambon Bay. Data sampling method which is conducted stationary utilizes pontoon mooring as floating platform for acoustic data sampling. Based on the analysis, diurnal migration of zooplankton occurs at noon, zooplankton swims in water surface to epipelagic zone (0-20 m) with value of scattering volume value -90.13 dB to -100.30 dB; it indicates sparse and scattered aggregation (N=128). At night, scattering volume of -90.01 dB to -100.30 dB indicates dense and concentrated aggregation (N=75). Scattering volume is numerical expression of zooplankton density. Chlorophyll a concentration in depth of 0-10 meter having the highest value of 5.16 ppb highly affects the existence of zooplankton. It functions for food availability of pelagic fish as its carnivore.