Preferensi Pakan dan Tingkat Trofik Layur (Trichiurus lepturus) di Perairan Muncar dan Prigi

ANIS NUARINTA, Dr. Eko Setyobudi, S.Pi., M.Si.; Dr. Ir. Djumanto, M.Sc.

2015 | Skripsi | S1 MANAJEMEN SUMBER DAYA PERIKANAN

Penelitian ini bertujuan untuk mengetahui preferensi pakan dan tingkat trofik layur (Trichiurus lepturus) di Perairan Muncar dan Prigi. Pengambilan sampel ikan dilakukan selama bulan September 2014 sampai dengan bulan Juni 2015 di PPP Muncar dan PPN Prigi. Total sampel layur berjumlah 214 ekor atau sejumlah 107 sampel dari setiap lokasi pengamatan. Setiap sampel diukur panjang tubuh, lebar bukaan mulut, panjang saluran pencernaan, dan komposisi jenis makanan. Pengukuran volume setiap jenis makanan dilakukan menggunakan gelas ukur dengan metode pemindahan air. Analisis data meliputi distribusi frekuensi panjang, lebar bukaan mulut ikan, panjang usus relatif, komposisi makanan, frekuensi kejadian, Indeks Bagian Terbesar (IBT), tingkat trofik, luas relung makanan, dan tumpang tindih relung makanan. Hasil penelitian menunjukkan bahwa makanan utama ikan layur adalah ikan dengan nilai IBT sebesar 80,5%. Jenis ikan yang dominan ditemukan sebagai makanan utama adalah ikan teri (ancovy) sebanyak 92% dan ikan karang (Carangidae) sebanyak 8%. Semakin besar ukuran ikan layur, maka komposisi ikan sebagai makanan utamanya akan semakin banyak. Layur termasuk ikan karnivora dengan nilai tingkat trofik sebesar 4,1.

The aims of this research was to determine the food preference and tropic level of hairtail (Trichiurus lepturus) in Muncar and Prigi Coast. Fish sample was collected on September 2014 to June 2015 in Muncar and Prigi fishing port. There were 214 and 107 individuals fish collected from Muncar and Prigi fishing port, respectively. Each individual fish was measured their total length, open mouth wide, digestive length, and feed material. The volume of each type of food was measured using scaling glass. The data analyzed was namely length distribution, mouth wide distribution, relative intestinal length, food composition, occurrence frequency, index of preponderance (IP), tropic level, niche breath, and food overlapping. The result showed that the main food was consist of fishes approximately IP 80,5%. The feed was dominated by anchovy approximately 92% and Carangidae approximately 8%. The composition of fish that was found on digestive canal higher when the size of hairtail was getting bigger. The tropic level approximately 4,1 that hairtail was carnivore.

Kata Kunci : karnivora, layur, Muncar, pakan, Prigi