Keanekaragaman jenis ikan non budidaya masih sering ditemukan pada tambak-tambak tradisional yang berada di perairan estuari dengan pengelolaan secara monokultur. penelitian ini bertujuan untuk mengidentifikasi keanekaragaman jenis ikan non budidaya di perairan tambak radisional muara sesayap. pengumpulan data dilakukan di perairan muara sesayap dari bulan april – juli 2019 dengan menggunakan alat tangkap jarring trawl. penelitian ini menggunakan metode deskriptif dengan data kualitatif. tahapan dalam penelitian terdiri dari penentuan tiga tambak tradisional, proses pemanenan, pengambilan sampel ikan non budidaya dan identifikasi sampel secara morfologi, dengan mengacu pada buku identifikasi. pengukuran parameter fisika-kimia air dilakukan sebelum dan sesudah proses pemanenan. hasil penelitian menunjukkan bahwa dari tiga lokasi penelitian diperoleh 25 spesies yang terdiri dari 3 kelas, 22 famili dan 25 genus. frekuensi relatif 100% jenis ikan yang di dapatkan pada tambak tradisional yakni sebayak 14 jenis ikan, frekuensi relatif 66,67% yakni sebayak 5 jenis ikan dan frekuensi terendah 33,3% yaitu sebanyak 6 jenis ikan. kata kunci: frekuensi relatif, kelimpahan spesies, perairan estuary

Diversity of wild fish species still often found in traditional ponds which is in the estuary waters with monoculture management. this study aims to identify diversity muara sesayap traditional ponds. data collection was carried out in the waters of muara sesayap from april - july 2019 by using a trawl net catcher. this research uses a descriptive method with qualitative data. stages in research consists of the determination of three traditional ponds, harvesting process, non-cultured fish sampling and identification of samples by morphology, concerning the identification book. measurement of physico-chemical parameters of water done before and after the harvesting process. the results showed that from three research locations obtained 25 species which consists of 3 classes, 22 families, and 25 genera. relative frequency of 100% of fish species obtain in traditional ponds, namely as many as 14 types of fish relative frequency is 66.67%, namely 5 types of fish and the lowest frequency was 33.3%, namely as many as 6 types of fish. keywords: relative frequency, species abundance, estuary waters