Nerona, Reu Arvin S.Almazan, Jerico M.Eliw, Laoren V.2026-06-252026-06-252024-07Nerona, R.A.S., Almazan, J.M., Eliw, L.V. (2024). Fish biodiverdity assessment in the estuary of Darigayos River, Luna, La Union captured using rama (a locally-based fishing method). [Unpublished Undergraduate Thesis, Don Mariano Marcos Memorial State University- North La Union Campus, Bacnotan, La Union]. Lakasa ti Sirib, DMMMSU Institutional Repository.https://lakasa.dmmmsu.edu.ph/handle/123456789/1931A biodiversity assessment was conducted in the estuary of Luna, La Union to identify the fish species and the diversity indices of the sampling sites along with their corresponding relative water quality parameters. The collection of samples in four (4) sampling sites resulted in a total of 3076 individuals belonging to 19 fish species. Notably, the Goby spp. dominated the total population with a relative abundance of 55%. The data analysis revealed that the four (4) sampling sites have a very low diversity index and have low evenness index with highest dominance index valued at site 2. Furthermore, the water quality parameters specifically DO and temperature were identified as important variable influencing fish species present while salinity and pH levels were relatively consistent across the sampling sites. These findings provide valuable insights of fish assemblages and help assess the current status of estuarine ecosystem in Darigayos, Luna, La Union.enThesis