KOMPOSISI LARVA IKAN DI ESTUARI OPAK KABUPATEN BANTUL

AGUNG AROHMAN, Dr. Ir. Djumanto, M. Sc.

2013 | Skripsi | MANAJ. SUMBER DAYA PERIKANAN

Penelitian ini bertujuan untuk mengetahui spesies dan struktur komunitas larva ikan di estuari Opak Kabupaten Bantul. Lokasi sampling dipilih sebanyak 5 stasiun yang mewakili keragaman kondisi estuari. Pengambilan sampel larva ikan dilakukan dengan menggunakan alat tangkap jaring larva berupa dok-dok dengan mesh size 1 mm. Jaring larva dengan luas 650 cm 2 didorong selama 45 menit di setiap stasiun. Pengambilan sampel dilakukan setiap 2 minggu sekali pada bulan September-November 2012. Sampel larva diawetkan di formalin 5 % kemudian dibawa ke laboratorium untuk diidentifikasi dan diukur. Identifikasi larva ikan dilakukan dengan 2 metode yaitu morfometrik dan meristik. Analisis komunitas larva ikan meliputi indeks jenis yang dominan, keanekaragaman jenis, kepadatan jenis, dan kemerataan jenis larva ikan. Hasil pengamatan menunjukkan bahwa terdapat 4 ordo, 8 famili, dan 8 spesies larva ikan, yaitu Albula sp., Ambassis vachellii, Channa striata, Liza subviridis, Oreochromis niloticus, Scatophagus argus, Stolephorus indicus, dan Terapon jarbua. Ambassis vachellii merupakan larva ikan paling dominan di estuari Opak. Indeks jenis yang dominan berkisar 0,34-0,74, keanekaragaman jenis berkisar 0,50-1,23, kepadatan jenis berkisar 0,30-0,09 ind/m 2 , kemerataan berkisar 0,36-0,69, dan salinitas berkisar 0-10 0 /00. Estuari Opak memiliki potensi sebagai nursery ground karena terdapat hutan mangrove sehingga harus dikelola dengan baik agar kelestarian populasi larva ikan tetap lestari.

The purpose of this research was to know larva fish species and structure of fish community which found in Opak estuary Bantul Regency. There were 5 sampling stations selected based on the environmental characters. Fish samples were collected by larva net with mesh size 1 mm. The larva net area was 650 cm 2 pushed to the nursery ground around 45 minutes in each station. Sampling was conducted every 2 weeks from September to November 2012. The samples were preserved in formalin 5 % then transfered to the laboratory for identification and measurement. The identification of the fish larva was carried out by using 2 methods that was morfometric and meristic. The analysis of data namely dominance, diversity, density, and evenness of fish larva. The result showed that there were 4 orders, 8 family, and 8 spesies of fish larva, that was Albula sp., Ambassis vachellii, Channa striata, Liza subviridis, Oreochromis niloticus, Scatophagus argus, Stolephorus indicus, dan Terapon jarbua. Ambassis vachellii was found the most dominance in the Opak estuary. The dominance index found between 0.34 and 0.74, the diversity index ranged 0.50-1.23, the density ranged 0.30-0.09 ind/m 2 , the evenness ranged 0.36-0.69, and the salinity ranged 0-10 0 /00. The Opak of estuari has becomed the potential as nursery ground because of the availability of mangrove as habitat for larva fish.

Kata Kunci : larva ikan, keanekaragaman jenis, estuari Opak