No abstract

No abstract

No abstract

Kranji waters have potential fishing grounds for the development of large marine fisheries. Kranji fishermen often face obstacles in their fishing efforts due to a lack of information about the season and potential fishing areas. The oceanographic factor of the waters can be one of the clues to determining a good catch. The purpose of this study was to determine the condition of the oceanographic parameters of the fishing area, determine the catch rate and determine the correlation of oceanographic parameters to the catch of ring trawlers. The data used in this study were temperature, salinity, depth, current velocity and catch for 10 fishing trips. Oceanographic parameters in the Kranji fishing area for 10 fishing trips were as follows: temperature ranged from 29.9- 31.8°C, water salinity ranged from 29-31.1‰, water depth ranges from 50-70 m and the current velocity ranges from 0.09to 0.34 m/s. The variability of ring trawl production during 10 times of capture found 5 species caught. The variability and composition of purse seine catches were as follows: Tongkol Walang with a percentage of 54.42%, Tongkol Lorek with a percentage of 38.13%, belo fish with a percentage of 6.37%, juwi with a percentage of 0.53%, and the lowest. the percentage is bagong by 0.52%. The correlation of oceanographic parameters with purse seine catches is as follows: Current velocity has the highest correlation value with a correlation coefficient of 0.814. The temperature has a strong category value with a correlation coefficient of 0.756. Salinity has a negative correlation value with a value of -0.658. Depth has a strong category value with a correlation coefficient value of 0.657.

This study aims to find out the activities of local sea cucumber methanol extract (Phyllophorus sp.) as a natural antifouling against macrofouler Nerita sp. This study uses experimental methods laboratory. Laboratory-scale data collection is carried out by observation of biota paste activities fouling on the aquarium (antifouling rate) as well as its regaining rate. This research uses research design complete random design (RAL) with three repetitions. Local sea cucumber methanol extract (Phyllophorus sp.) contains bioactive compounds such as saponins, alkaloids, tannins, steroids and phenolics. Methanol Extract local sea cucumber (Phyllophorus sp.) affects the antifouling rate by reducing the Nerita sp. macrofouler paste rate with increasing concentration. It's the same thing,occurs where the increasing concentration of local sea cucumber methanol extract (Phyllophorus sp.) provides a significant decrease in Nerita sp. macrofouler regaining capability. The results lethal concentration 50 or LC50 obtained a value of 185.18. This means the concentration of the extract sea cucumber (Phyllophorus sp.) is deadly 50% of all biota test at a concentration of 185.18 mg/ml. Based on antifouling rate analysis and regaining rate it is known that the concentration of the most effective that can be used as an antifouling is a concentration of 75 mg/ml. This is because a concentration of 75 mg/ml of local sea cucumber methanol extract (Phyllophorus sp.) can already inhibit paste macrofouler Nerita sp. The concentration of 75 mg/ml also has a large regaining rate of 85%.