Electronic Theses and Dissertation

Famili Scombridae merupakan kelompok ikan pelagis yang memiliki nilai ekonomi tinggi dan banyak dimanfaatkan oleh masyarakat pesisir di wilayah Meulaboh, Aceh Barat. Namun, identifikasi spesies secara morfologi sering kali mengalami kendala akibat kemiripan ciri antar spesies serta kondisi fisik sampel yang tidak utuh saat didaratkan. Oleh karena itu, penelitian ini dilakukan untuk mengidentifikasi spesies Scombridae secara molekuler menggunakan pendekatan DNA barcoding berbasis gen Cytochrome Oxidase Subunit I (COI). Pengambilan sampel dilakukan pada bulan Oktober 2024 di Tempat Pendaratan Ikan (PPI) Ujong Baroh, Meulaboh. Analisis molekuler berhasil mengamplifikasi fragmen sepanjang 639 pasangan basa. Hasil identifikasi menunjukkan bahwa terdapat empat spesies yang berhasil dikenali, yaitu Auxis rochei (5 individu), Katsuwonus pelamis (5 individu), Euthynnus affinis (5 individu), dan Thunnus albacares (5 individu). Rata-rata jarak genetik antar spesies berdasarkan model Kimura 2-Parameter (K2P) adalah sebesar 0,002. Jarak genetik terdekat ditemukan antara Euthynnus affinis dan Auxis rochei (0,069%), sedangkan jarak terjauh antara Thunnus albacares dan Euthynnus affinis (0,109%). Berdasarkan data dari IUCN Red List, keempat spesies tergolong dalam kategori konservasi “Least Concern”, namun tren populasi menunjukkan bahwa Katsuwonus pelamis dan Thunnus albacares mengalami penurunan di alam. Temuan ini memberikan kontribusi penting terhadap basis data keanekaragaman genetik dan dapat menjadi landasan ilmiah dalam upaya konservasi serta pengelolaan berkelanjutan sumber daya ikan Scombridae di perairan Meulaboh.

Kata kunci : DNA barcoding, Scombridae, COI, identifikasi molekuler, keanekaragaman genetik, Meulaboh, pengelolaan perikanan

The Scombridae family consists of pelagic fish species with high economic value and is widely utilized by coastal communities in Meulaboh, West Aceh. However, morphological identification of species often encounters challenges due to similarities in physical characteristics among species and the poor condition of samples upon landing. Therefore, this study aimed to identify Scombridae species through molecular approaches using DNA barcoding based on the Cytochrome Oxidase Subunit I (COI) gene. Sampling was conducted in October 2024 at the Ujong Baroh Fish Landing Site (PPI), Meulaboh. Molecular analysis successfully amplified a DNA fragment of 639 base pairs. Four species were identified, namely Auxis rochei (5 individuals), Katsuwonus pelamis (5 individuals), Euthynnus affinis (5 individuals), and Thunnus albacares (5 individuals). The average genetic distance among species, based on the Kimura 2-Parameter (K2P) model, was 0.002. The closest genetic distance was observed between Euthynnus affinis and Auxis rochei (0.069%), while the greatest distance occurred between Thunnus albacares and Euthynnus affinis (0.109%). According to the IUCN Red List, all four species are classified as “Least Concern,” although population trends indicate a decline in Katsuwonus pelamis and Thunnus albacares in the wild. These findings provide essential contributions to the genetic diversity database and serve as a scientific foundation for the conservation and sustainable management of Scombridae fish resources in the waters of Meulaboh. Keywords : DNA barcoding, Scombridae, COI, molecular identification, genetic diversity, Meulaboh, fisheries management