The Biological Aspects of the Main Targets of Troll Line at Palabuhanratu Fishing Port, Indonesia

The biological aspect is a piece of basic information that is commonly presented in assessing the level of environmental friendliness of fishing gear or fishing vessel. This study was conducted to analyze the biological aspects of the main catch of the troll line at the Palabuhanratu Fishing Port, Sukabumi, Indonesia. The biological aspects analyzed consisted of length frequency distribution, length-weight relationship, to the average feasibility status of the caught target fish. There were three main target commodities for fishing from the troll line that was identified during the research activity, namely yellowfin tuna (Thunnus albacares), skipjack tuna (Katsuwonus pelamis), and frigate tuna (Auxis thazard). A total of 14 troll line fleets were obtained as a source of research data based on the accidental sampling method. The total number of 1404 fish consisting of 480 yellowfin tuna, 475 skipjack tuna, and 449 frigate tuna were obtained as research data objects. The stratified random sampling method was used in determining the observed sample fish data. Yellowfin tuna were distributed at size 29 – 148 cm, skipjack tuna at size 29 – 88 cm, and frigate tuna at size 23 – 82 cm. Analysis of the length-weight relationship showed a negative allometric growth pattern in the three main fishing target commodities. The analysis of the feasibility of the average fish caught based on compared of L50% to ½ L∞ shows that the average size of tuna and frigate tuna caught is undersize for catching, while the average skipjack caught has reached a legal size. The results of this study indicate that there is a need for a review of the use of fishing hooks in the fishing activity of the troll line fishing fleet. Increasing the hook size can be used to avoid catching fish that are at a size that is not suitable for catching.