EFFECTS OF LUNAR PERIODICITY IN THE HEPATOSOMATIC AND GONADOSOMATIC INDEX OF Scarus vetula (Bloch & Schneider, 1801) IN THE SELECTED COASTAL WATERS OF SARANGANI BAY

This study aims to provide information about the Gonadosomatic and Hepatosomatic Indices of the selected parrotfish species (Scaridac) Scarus vetula which is commonly fished in the coastal waters of Sarangani bay and to analyze the relationship between different lunar phases in the Hepatosomatic and Gonadosomatic index of Scarus vetula, Samples of parrotfish Scarus vetula were taken from two different fishing grounds for three consecutive months from March to May 2018 in every moon phase to analyze its Hepatosomatic and Gonadosomatic index. Analysis shows that there is a significant difference in the Gonadosomatic index between moon phases showing its highest peak on the Last quarter and lowest in the new moon indicating that spawning starts after the last quarter of the lunar phases. Hepatosomatic index also shows a significant difference between moon phases showing its highest peak in the first quarter and lowest during the last quarter. A significant positive correlation was also observed between G.S.I and H.S.I in first quarter. Yet only last quarter shows a significant negative correlation. These results will give us more understanding about the reproductive cycle and feeding activity of Scarus vetula which can also help policy makers and environmentalist in the conservation and proper management of fish diversity and demersal reef fishery.