Predation of anchovy during capture process of bagan rambo: its relation to plankton abundance

Abstract

AMIRUDDIN. Predation of Anchovy during Capture Process of Bagan Rambo: its Relation to Plankton Abundance. Under the supervision of M. Fedi A. Sondita, Richardus F. Kaswadji and Domu Simbolon. Fish movement into the catchable area of bagan rambo (lifnet) may not only due to the influence of light but also the presence of their preys. Hence, there maybe some interaction amo ng biotas in the catchable area that builds a food chain. This research describes anchovy, its preys (the plankton) and predators of the anchovy during capture process. Data were collected during bagan rambo operation from May – July 2005 in 8 locations in Makassar Strait. The interaction between the anchovy and plankton, and between anchovy and its predators ware based on the presence and quantitative of substances found in the digestive system of the anchovy and its predators, and the correlation between the catch of the anchovy and the abundance of the plankton. There was significant correlation between the amount of anchovy food in its stomach and the abundances of zooplankton in the waters (R2 = 0,643), but not with abundances of phytoplankton. Number of anchovy predated by its prey was also correlated with the abundances of the anchovy (R2 = 0,403). The anchovy was also preyed mainly selar (Selar); other predator were peperek (Leiognathus), alu-alu (Sphyraena), buntal (Diodon), kwee (Caranx), kerong-kerong (Therapon), bambangan (Lutjanus) and lencam (Lethrinus).