Preferensi Pakan Ikan Layur (Trichiurus lepturus, linnaeus 1758) di Perairan Pantai Ngrenehan Kabupaten Gunungkidul

Akhmaz Faiz Ashifuddin, Dr. Eko Setyobudi, S.Pi., M.Si.

2023 | Skripsi | MANAJ. SUMBER DAYA PERIKANAN

Penelitian ini bertujuan untuk mengetahui jenis dan preferensi pakan ikan layur (Trichiurus lepturus) di perairan Pantai Ngrenehan, Kabupaten Gunungkidul. Sebanyak 197 sampel ikan layur diambil dari hasil tangkapan nelayan di perairan Pantai Ngrenehan Gunungkidul pada bulan Desember 2022–Februari 2023. Setiap sampel ikan diukur panjang total dan berat, lalu dibedah untuk mengamati saluran pencernaan. Analisis data yang dilakukan meliputi distribusi panjang dan berat, panjang usus relatif, komposisi makanan, frekuensi kejadian, indeks bagian terbesar, tingkat trofik, luas relung makanan, dan tumpang tindih makanan. Hasil penelitian menunjukkan bahwa ikan layur di perairan Pantai Ngrenehan Gunungkidul merupakan jenis karnivora dengan panjang usus relatif 0,122–0,281, dan tingkat trofik 3,10. Komposisi makanan ikan layur di perairan Pantai Ngrenehan Gunungkidul adalah potongan ikan (27%), debris hewan (47%), krustasea (23%), dan cumi-cumi (3%). Berdasarkan kelas ukuran, makanan utama ikan layur pada kelas ukuran <57>61 cm berupa potongan ikan dengan nilai indeks bagian terbesar (IBT) paling tinggi bernilai 50,38%. Nilai luas relung berkisar antara 1,93-2,04 dengan nilai standardisasi 0,31-0,35. Terjadi adanya persaingan antar ukuran ikan layur terhadap sumber makanan dengan nilai tumpang tindih berkisar antara 0,977-0,994.

This study aims to determine the composition and food preferences of largehead hairtail (Trichiurus lepturus) in the Ngrenehan Coastal waters, Gunungkidul Regency. In total, 197 largehead hairtail samples were taken from fishermen who caught in the Ngrenehan Coastal waters Gunungkidul Regency from December 2022 to February 2023. Each fish sample was measured for total length and weight, then dissected to observe the digestive tract. Data analysis included length and weight distribution, relative gut length, food composition, frequency of occurrence, index of largest part, trophic level, food niche area, and food overlap. Largehead hairtails caught at Ngrenehan Coastal waters Gunungkidul are carnivorous, with a relative gut length ranging from 0.122 to 0.281 and a trophic level of 3.10. The diet composition of the hairtail was fish pieces (27%), animal debris (47%), crustacea (23%), and squid (3%). Based on size, the main food of largehead hairtail in the size class <57>61 cm was fish, with the highest preponderance index of 50.38%. Food niche breadth ranged from 1.93-2.04 with a standardized value of 0.31-0.35. There was competition for food sources between the largehead hairtails, with food overlapping values ranging from 0.977 to 0.994.

Kata Kunci : karnivora, komposisi makanan, luas relung, tingkat trofik, tumpang tindih, carnivores, diet breadth, diet overlap, food composition, trophic level