DISTRIBUSI DAN KELIMPAHAN LARVA IKAN DI KAWASAN PERAIRAN PANTAI DUKUH BEDONO KECAMATAN SAYUNG KABUPATEN DEMAK (Distribution and Abundance of Fish Larvae in Coastal Waters of Bedono Village, Sayung, Demak Regency)

Abstract

Larva ikan merupakan fase kehidupan awal dari pertumbuhan ikan dimana perkembangan organ tubuh belum terbentuk secara sempurna. Distribusi dan kelimpahan larva ikan sangat bergantung pada kondisi perairan di dalamnya. Kawasan perairan pantai merupakan perairan yang terhubung langsung ke laut dan masih dipengaruhi oleh aktivitas daratan. Perairan pantai dukuh Bedono mengalami degradasi akibat berkurangnya tanaman mangrove dan terjadinya rob. Penelitian ini bertujuan untuk mengetahui distribusi dan kelimpahan larva ikan di kawasan perairan pantai dukuh Bedono. Penelitian dilaksanakan pada bulan Maret-April 2017. Metode penelitian yang digunakan adalah survei dengan penentuan titik sampling secara purposive. Hasil yang diperoleh menunjukkan bahwa jumlah larva ikan yang tertangkap sebanyak 2.064 individu terdiri dari 10 famili yakni: Ambassidae (245 ind/100 m³), Mugilidae (507 ind/100 m³), Chanidae (378 ind/100 m³), Engraulidae (288 ind/100 m³), Lutjanidae (73 ind/100 m³), Nemipteridae (109 ind/100 m³), Carangidae (145 ind/100 m³), Gobiidae (160 ind/100 m³), Gerreidae (92 ind/100 m³), dan Oryziatidae (67 ind/100 m³). Larva ikan famili Mugilidae tertangkap paling banyak selama pelaksanaan penelitian. Berdasarkan analisis indeks morisita, pola sebaran larva ikan adalah acak. Kesimpulan yang dapat diperoleh ialah nilai kelimpahan larva ikan tertinggi terdapat pada titik IV sebesar 267 ind/100m³ dan terendah terdapat pada titik III sebesar 185 ind/100 m³. Pola persebaran larva ikan pada semua titik adalah acak dimana semua larva ikan dapat menyesuaikan dan bertahan hidup di mana saja pada suatu ekosistem.

Fish larvae are the early life phase of the growth of fish where the development of organs has not been fully formed. The distribution and abundance of fish larvae depend on the condition of the waters in it. Coastal waters are waters that connect directly to the sea and are still influenced by land activities. The coastal waters of Bedono village have degradation due to the decreasing of mangrove plant and the increasing of seawater period. This study aims to determine the distribution and abundance of fish larvae in the coastal region of Bedono village. The research was conducted in March-April 2017. The research method used was a survey with purposive sampling point. The results showed that the number of captured fish larvae of 2,064 individuals consisted of 10 families: Ambassidae (245 ind/100 m³), Mugilidae (507 ind/100 m³), Chanidae (378 ind/100 m³), Engraulidae (288 ind/100 m³) , Lutjanidae (73 ind/100 m³), Nemipteridae (109 ind/100 m³), Carangidae (145 ind/100 m³), Gobiidae (160 ind/100 m³), Gerreidae (92 ind/100 m³), and Oryziatidae (67 ind/100 m³). Fish larvae of the Mugilidae family were caught at the most during the study. Based on the morisita index analysis, the pattern of fish larvae distribution is random. The conclusion that can be obtained is the highest value of fish larvae abundance found at point IV of 267 ind/100 m³ and the lowest is at point III of 185 ind/100 m³. The pattern of the distribution of fish larvae at all points is unevenly where all fish larvae can adapt and survive anywhere in an ecosystem.