Marine Ecological Analysis: Composition and Catch Diversity of Mini Purse Seine Fisheries in the Coastal Ecosystem of Jepara, Central Java

Ujungbatu Fish Auction Site is a coastal fisheries centre in Jepara Regency. The operation of mini purse seine contributes the most to fishery production than other fishing gears. Mini purse seines in Jepara Regency target small pelagic fish. Mini purse seine fisheries in Jepara are multi-species and operating one day fishing. The study aims to analyze the diversity of mini purse seine catches in Jepara coastal waters. Data collection was based on secondary data in the form of mini purse seine fisheries production data from Fish Auction Site Office. The data calculate to get the catch composition, Shannon-Wiener diversity index and Simpson's dominance index. Additionally, one-way ANOVA analysis used to determine the significant differences in species proportions. The results identified five fish species, namely Mackerel Tuna (Euthynnus affinis), Indian Mackerel (Rastrelliger sp), Scads (Decapterus sp.), Squids (Loligo sp.), and Narrow-barred Spanish Mackerel (Scomberomorus sp.), with the highest catch was Indian Mackerel (26.40%). The one-way ANOVA show that there is no significant difference between the types of catches in each year. The diversity index was moderate (H=1.56), and the dominance index was low (C=0.22). This reflects a stable ecosystem with an even distribution of species and no significantly dominating species.