The food of Parachanna obscura in Asejire reservoir, Oyo State Nigeria

Abstract

Investigations were carried out on the food of Parachanna obscura (Gunther, 1861). Parachanna obscura fed intensively during the rainy season. During this period 86.8% of its stomachs contained food, while 32.3% was observed during the dry season. Stomach content analysis showed that this species is a carnivore which feed both on fish and insects. The small fish specimens (TL 12.0 – 26.0cm) preferred insects (90.2%) as food to fish (37.5%), while the larger specimens (TL 27.0 – 41.0cm) preferred fish items (62.5%) to insects (9.8%) as revealed by the frequency of occurrence of these food items in the stomach of fish specimens examined. The relative importance of different food items ingested by this fish is documented. The weight of food ingested by P. obscura did not vary significantly (P > 0.05) with the size of fish, but with the type of diet consumed by the fish. Energy contents of ingested food by this fish also did not vary significantly with increase in fish body weight. The energy contents in food of wet season specimens were higher than those of the dry season specimens, though this difference was observed not to be statistical (P > 0.05).


Key Words: Food-items, Dry weight, Energy, Fish-size, Parachanna obscura


Global Jnl Pure & Applied Sciences Vol.10(2) 2004: 263-269