Variation in environmental characteristics of waters among oyster and mussel culture areas in Pilar Bay, Capiz

This study assessed the ongoing environmental suitability and zonation of oyster (Crassostrea iredalei) and mussel (Perna viridis) culture areas within Pilar Bay, Capiz, with the aim of identifying optimal areas for continued or potential expansion of shellfish farming. The study was conducted in the municipalities surrounding Pilar Bay. In situ measurements of physicochemical parameters, including temperature, salinity, dissolved oxygen (DO), pH, oxidation-reduction potential (ORP), and conductivity, were conducted monthly across seven sampling sites from January to December 2023. Data were analyzed statistically using SPSS, and a geotagged map of the oyster and mussel culture areas was generated. Results showed significant differences in physicochemical parameters across months and sites, except for dissolved oxygen and salinity. Variations in environmental characteristics were attributed to freshwater influx from frequent precipitation, flooding, and tidal fluctuations. Water quality evaluation revealed that all sites station were capable and moderately suitable for oyster culture, except Pinamihagan (sites 1 and 2), which were categorized as poor. For mussel culture, Buntod (Site 1) emerged as the most suitable site, rated as excellent.