Gillnet Selectivity on the Narrow-barred Spanish Mackerel (Scomberomorus commerson) Fishery in Pangandaran Waters

Abstract

Analyzing the selectivity of gillnet fishing gear using two different mesh sizes, namely 3.5 and 4 inches. Gillnets of these mesh sizes are commonly used by fishermen in Fish Landing Base (PPI) Cikidang, Pangandaran Regency, West Jawa. A total of 8 fishing trips were conducted at the coastal waters around PPI Cikidang, Pangandaran Regency, West Java from August 2018 to January 2019  using gillnet fishing gear As for each trip, 2-3 times the operation of the tool is carried out. The operation of the fishing gear is carried out with the help of vessels measuring 2-3 Gross Tonnage (GT). The catch obtained was differentiated based on the main catch and bycatch and the amount is calculated for analysis of the proportion of the catch. Mackerel (Scomberomorus commerson) is caught as the main catch, the fork length was measured for analysis of the length frequency distribution and selectivity curves. The operation of gillnets with a mesh size of 3.5 inches obtained a higher proportion of bycatch compared to gillnets with a mesh size of 4 inches. In addition, the length distribution of mackerel caught by gillnets with a mesh size of 3,5 inches is smaller (27-49 cm FL) compared to a mesh size of 4 inches (40-55 cm FL). Based on the distribution of length distribution, gillnets with a mesh size of 3.5 inches are more dominant in catching mackerel in a smaller size class interval than gillnets with a mesh size of 4 inches. Meanwhile, based on the selectivity curve for the length of mackerel with a 50% chance of being caught, it shows that gillnets with a mesh size of 3.5 or 4 inches are selective in catching mackerel, this is because the chances of catching fish at more than L50 are high.