Budidaya ikan air tawar yang paling banyak dibudidayakan di Kota Tarakan adalah ikan lele dumbo (Clarias gariepinus). Budidaya ikan lele dumbo (Clarias gariepinus) semakin berkembang menunjukkan bahwa minat masyarakat dalam mengkomsumsi ikan meningkat. Penyakit bakterial adalah penyakit yang biasa menyerang ikan lele dumbo. Penelitian ini bertujuan untuk mengetahui jenis-jenis patogen bakteri dan dampak dari serangan bakteri yang ada pada ikan lele dumbo yang dibudidayakan di Kota Tarakan. Metode pengambilan data yang digunakan dalam penelitian adalah metode deskriptif dengan metode pengambilan sampel ikan lele dumbo dilakukan secara random sampling. Penelitian ini dilaksanakan dari bulan Maret- Agustus 2022. Isolat bakteri diperoleh dari bagian tubuh ikan yang luka, lendir, hati, ginjal dan usus. Bakteri ditumbuhkan pada media TSA dan diidentifikasi menggunakan uji KOH 3%, Katalase, Oksidase, O/F, MIO, dan Glukosa. 45 sampel ikan lele dumbo dari 3 lokasi budidaya didapatkan hasil identifikasi bakteri yang menyerang ikan lele dumbo yaitu sebanyak 4 jenis bakteri dari Aeromonas sp. Plesiomonas sp. Vibrio sp, dan Enterobacter sp. Dampak dari serangan bakteri membuat 25% produksi ikan lele di tiga lokasi budidaya berkurang. Parameter kualitas air di tiga lokasi budidaya selama penelitian menunjukkan bahwa Suhu berkisar 30 oC, pH berkisar 6,8-8,8, dan Amoniak berkisar 2,1-2,8 mg/L yang diperoleh masih dapat berada pada batas optimum, sedangkan oksigen terlarutnya rendah berkisar 0,46-2,76 mg/l.
Kata Kunci: Bakterial, Identifikasi, Isolasi, Lele Dumbo

The most widely cultivated freshwater fish in Tarakan City is the African catfish (Clarias gariepinus). The cultivation of African catfish (Clarias gariepinus) is growing, indicating that people's interest in consuming fish is increasing. Bacterial disease is a disease that usually attacks African catfish. This study aims to determine the types of bacterial pathogens and the impact of bacterial attack on African catfish cultured in Tarakan City. The data collection method used in this study is a descriptive method with the method of sampling African catfish by random sampling. This research was conducted from March to August 2022. Bacterial isolates were obtained from injured fish body parts, mucus, liver, kidneys and intestines. Bacteria were grown on TSA media and identified using 3% KOH, Catalase, Oxidase, O/F, MIO, and Glucose assays. 45 samples of African catfish from 3 cultivation locations obtained the identification of bacteria that attack African catfish, namely as many as 4 types of bacteria from Aeromonas sp. Plesiomonas sp. Vibrio sp, and Enterobacter sp. The impact of bacterial attack reduced 25% of catfish production in the three cultivation locations. Water quality parameters in the three cultivation locations during the study showed that the temperature ranged from 30 oC, pH ranged from 6.8 to 8.8, and ammonia was in the range of 2.1 to 2.8 mg/L that was obtained could still be at the optimum limit, while oxygen low solubility ranged from 0.46-2.76 mg/l.