Gonad Maturity and Fecundity of Indian Mackerel (Rastellinger kanagurta) in North Gorontalo Waters, Indonesia

Abstract

Indian mackerel (Rastellinger kanagurta) is one of the fish that can be caught by fishermen in North Gorontalo waters. Excessive fishing without regard to the condition of the fish will cause a decrease in the quality and quantity of fish resources. Estimation of size at first maturity is one way to determine population development in water. This study aims to determine the relationship between the level of gonad maturity and the fecundity of Indian mackerel in North Gorontalo waters. This research was conducted in October-December 2021 at the Kwandang Archipelago Fishing Port. The level of maturity of the gonads was observed morphologically and the determination of fecundity was observed using volumetric and gravimetric methods. The maturity level of Indian Mackerel fish in North Gorontalo waters is dominated at level 1. The highest fecundity is 14,800 eggs and the lowest is 5,000 eggs. The relationship between the level of gonad maturity and fecundity is directly proportional, if the gonadal maturity value is high, the fecundity value will also be higher. The spawning season for Indian mackerel in North Gorontalo waters does not take place in October-December, this is characterized by low fecundity. Based on the gonadal maturity values every month, the peak spawning of Indian mackerel (Rastellinger kanagurta) allegedly occurred shortly after the highest GSI values.