Distribution fisheries resources of Small Island in Estuary Area: An assessment in Bunyu Island, North Kalimantan, Indonesia

Understanding the spatial distribution of potential fish resources can optimize the management of capture fisheries, especially in coastal areas on small islands with limited supporting activities factors. Swept analysis is applied to the study of distribution of fish resources in waters around Bunyu Island in order to estimate spatial distribution of fish populations in Bunyu Island waters of North Kalimantan based on biomass, weight and number of fish abundance and to examine the effect of different sampling location and time difference of observation. Observations were made in 8 sampling areas around Bunyu Island waters in 3 periods, namely the southern season, the peak of southern seasons and the transition of the southern seasons to the northern seasons. Fish resources found in Bunyu Island waters are 59 species and non fish are 18 species, consist of 61 species of demersal fish and 16 pelagic species. Types of dominant demersal fish caught are 6 species and always found in 3 sampling periods namely Gulamah (Belanger's croaker, Johnius belangerii), Kuniran (Goat fishes, Upeneus sulphureus), Kurisi (Threadfin bream, Nemipterus sp.), Ote-Ote/Manyung (catfishes/Arius caelatus), Pepetek (ponyfish, Leiognathus sp.), and Puput (ray-finned fishes, Ilisha elongata). By area, the total biomass of fish resources from the three surveys showed variation. The lowest biomass of fish resources was found in the southeast of Bunyu Island (area H) of 890.92 kg / km2 and the highest was found in the southern area of Bunyu Island (area G) of 3804.11 kg / km2. Area H shows consistency in the least amount of biomass in each survey. Differences in biomass of fish resources are affected by the migration of fish determined by changes in sea current patterns, food availability, and predation.