PENGAMATANISILAMBUNG BEBERAPA JENISIKAN BUNTAL ('Tetraodon reticularis, T. fluviatilis, I lunaris) DI PERAIRAN UJUNG PANGKAH, JAWA TIMUR [Study on the Stomach Contents of Some Puffer Fishes (Tetraodon reticularis, T. fluviatilis, T. lunaris) in Ujung Pangkah Waters, East Java]

Abstract

Study on the stomach contents of some puffer fishes (Tetraodon reticularis, T. fluviatilis, T. lunaris) was done from March 2000 to April 2001 in Ujung Pangkah Waters, East Java. Samples were collected monthly using gill net mesh sized of 2.5 and 4.5 cm. Stomach content was preserved by formalin 10% and observed under microscope (50 magnification). Analysis was carried out to estimate Index of Stomach content (ISC) and Index of Preponderance (IP). The result showed that main food of male Tetraodon reticularis was Balamis sp.. suplemen food was bivalva and debris, and additional food, gastropods and crab. While main food of female fish was Balamis sp., suplemen food w'as debris and bivalve, and additional food was shrimp, crab, and gastropoda. Main food of male T. fluviatilis was Balamis sp., suplemen food was gastropoda, additional food was shrimp, bivalve, fish and green mussel. While for female fish, the main food was Balamis sp., suplemen food was bivalve and shrimp, and additional food was gastropoda, crab, fish and bivalve. Main food of male T. lunaris was fish, suplemen food was bivalve, shrimp and gastropoda, and additional food was Balanus sp., crab, green mussel and unidentified organisms. While main food of female fish was fish, suplemen food was shrimp and bivalva, and additional food was Balanus sp., crab, gastropoda and unidentified organisms. The ISC seems on August (male) and September (female) for T. reticulates, on April (male) and May (female) for T. fluviatilis, and on April (male) and December (female) for T. lunaris.

ABSTRAK

Pengamatan terhadap isi lambung beberapa jenis ikan buntal (Tetraodon reticularis, T. fluviatilis, T. lunaris) dilakukan sejak Maret 2000 sampai April 2001 di perairan Ujung Pangkah, Jawa Timur. Sampel ikan ditangkap per bulan dengan menggunakan gill net (mata jaring 2,5 dan 4,5 cm). Isi lambung diawet dengan formalin dan diamati di laboratorium. Analisis dilakukan untuk menentukan indeks isi lambung (ISC) dan indeks bagian terbesar (IP). Hasil pengamatan didapatkan bahwa jenis Tetraodon reticularis jantan memiliki makanan utama berupa Balanus sp., makanan pelengkap berupa bivalva, serasah, dan an makanan tambahan berupa ikan, gastropoda dan kepiting. Sedangkan untuk ikan betina, makanan utama berupa Balanus sp., makanan pelengkap berupa serasah dan bivalve, dan makanan tambahan berupa udang, kepiting dan gastropoda. T. fluviatilis jantan memiliki makanan utama berupa Balanus sp., makanan pelengkap berupa gastropoda, makanan tambahan berupa udang, bivalve dan ikan. Sedangkan untuk ikan betina makanan utamanya berupa Balanus sp., makanan tambahan berupa bivalve dan udang, dan makanan pelengkap berupa gastropoda, kepiting, ikan dan bivalve. T. lunaris jantan makanan utamanya berupa ikan, makanan pelengkap berupa bivalve, udang dan gastropoda, dan makanan tambahannya berupa Balanus sp., kepiting, bivalve dan organisme tak teridentifikasi. Sedangkan untuk jenis ikan betina memiliki makanan utama berupa ikan, makanan pelengkap berupa udarrg dan bivalve, dan makanan tambahannya berupa Balamis sp., kepiting, gastropoda dan organisma tak teridentifikasi. T. reticulates terlihat memiliki ISC yang lebih tinggi pada bulan Agustus (Jantan) dan September (betina), T. fluviatilis pada bulan April (jantan) dan Mei (betina), dan T. lunaris pada bulan April (jantan) dan Desember (betina).