Keanekaragaman Jenis Ikan di Sungai Opak-Oyo Kabupaten Bantul

Agus Ahmad Nur Faadhlil, Drs. Namastra Probosunu, M.Si.

2026 | Skripsi | MANAJ. SUMBER DAYA PERIKANAN

Sungai Opak-Oyo merupakan ekosistem perairan yang berperan sebagai habitat berbagai jenis ikan di Kabupaten Bantul. Penelitian ini bertujuan untuk mengetahui komposisi jenis ikan, struktur komunitas ikan berdasarkan indeks keanekaragaman dan dominasi, serta kondisi lingkungan perairan di hilir hingga muara Sungai Opak-Oyo. Penelitian dilakukan pada November-Desember 2025 di lima stasiun pengamatan. Pengambilan sampel ikan dilakukan menggunakan jala, bubu, dan pancing dengan delapan kali pengulangan. Parameter kualitas perairan yang diamati meliputi suhu, pH, oksigen terlarut (DO), kecepatan arus, dan kedalaman. Data dianalisis secara deskriptif menggunakan indeks keanekaragaman Shannon-Wiener (H') dan indeks dominasi Simpson (D). Hasil penelitian yang telah dilakukan, di Sungai Opak-Oyo berhasil ditemukan 235 individu ikan yang terdiri atas 15 spesies dari 10 famili. Famili Cyprinidae merupakan famili dengan jumlah spesies terbanyak. Spesies yang paling banyak tertangkap adalah Caranx ignobilis (38,30%), sedangkan yang paling sedikit yaitu Barbonymus gonionotus dan Anguilla bicolor (0,85%). Nilai rata-rata indeks keanekaragaman (H') sebesar 1,46 termasuk kategori sedang, sedangkan indeks dominasi (D) sebesar 0,36 termasuk kategori rendah. Kondisi lingkungan perairan masih mendukung kehidupan ikan dengan suhu rata-rata 30,05 C, pH 7,74, DO 8,89 mg/L, kecepatan arus 0,10 m/dt, dan kedalaman 59,80 cm.

The Opak-Oyo River is an aquatic ecosystem that serves as a habitat for various fish species in Bantul Regency. This study aims to determine the composition of fish species, the structure of the fish community based on diversity and dominance indices, and the environmental conditions of the waters downstream to the estuary of the Opak-Oyo River. The study was conducted in November-December 2025 at five observation stations. Fish sampling was carried out using nets, traps, and fishing lines with eight repetitions. Water quality parameters observed included temperature, pH, dissolved oxygen (DO), current velocity, and depth. Data were analyzed descriptively using the Shannon-Wiener diversity index (H') and the Simpson dominance index (D). From the results of the study, 235 individual fish were found in the Opak-Oyo River consisting of 15 species from 10 families. The Cyprinidae family is the family with the largest number of species. The most frequently caught species was Caranx ignobilis (38.30%), while the least caught were Barbonymus gonionotus and Anguilla bicolor (0.85%). The average diversity index (H') of 1.46 is categorized as moderate, while the dominance index (D) of 0.36 is categorized as low. The aquatic environment still supports fish life with an average temperature of 30.05 C, pH 7.74, DO 8.89 mg/L, current velocity 0.10 m/s, and depth 59.80 cm.

Kata Kunci : dominasi, keanekaragaman, komunitas ikan, sungai Opak-Oyo.