Food habits and biolimnology of snakehead larvae and fingerlings from different habitats.

Abstract

Snakehead (Channa striata) is widely distributed particularly in Asian and African countries, and has become one of the favorite freshwater fish commodities, which beneficially supports the aquaculture sector and fish processing industries. However, high mortality rate, slow growth and susceptibility to parasite attacks are serious problems. This study aims to investigate the food habits related to biolimnology parameters of snakehead larvae and fingerlings as a fundamental input for better aquaculture management. The study sites were located at Danau Bangkau Village (monotonous swamp), Anjir Muara Village (tidal swamp) and Sungai Batang Village (streams) of South Kalimantan Province, Indonesia. The food habits of the larvae were studied with the plankton habitat analytical approach, while those of the fingerlings (48-74 mm and 3.4-7.7 g) were analyzed using the Index of Preponderance. The results showed that the larvae mostly consumed chlorophyta (31.11%), followed by chrysophyta (19.11%), cyanophyta (14.67%), protozoa (14.67%), crustaceae (10.22%), rotifera (8.89%) and insecta (1.33%), while the fingerlings preferred small fish (61.05%) rather than frogs (15.06%), mollusks (11.47%), crustaceans (10.35%), and worms (1.67%). The fingerling males were more susceptible to parasites attacks compared to females. The parasite population was dominated by Lernea sp., Argulus sp., Gyrodactylus sp. and Ichthyophthirius sp. The abundance of plankton was categorized in the moderated fertility level, and water quality parameters were in the tolerant range for the growth and survival of the larvae and fingerlings.