Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt

Abstract

ABSTRACThe present study is concerned with the seasonal analysis of the stomach contents of three species of cichlid fishes inhabiting Damietta branch of the River Nile, Egypt, namely Oreochromis niloticus (Linn., 1758), Sarotherodon galilaeus (Linn., 1758) and Tilapia zillii (Gerv., 1848). The natural food was studied from the stomach contents of fish ranging from 12-29, 11-24 and 10-21 cm in total length of the previous species, respectively. Stomach contents were analyzed using the frequency of occurrence and Percentage of composition methods. Additionally, feeding intensity, index of relative importance (IRI) and selectivity index (S) were calculated. The results showed that, food from plant origin dominates the diet of the three studied species and occurred frequently in more than 60.0% of the examined stomach. Values of IRI emphasized the importance of diatoms, blue green and green algae as major food resources in the stomach of O. niloticus followed by rotifers and organic detritus. S. galilaeus and T. zillii followed nearly the same trend as O. niloticus, but plant tissues follow blue green and green algae in the diet of T. zillii. IRI indicates also the importance of food of animal origin in the diets of O. niloticus and S. galilaeus than T. zillii. The feeding intensity is strongly influenced by season, since the highest stomach fullness occurred during summer. In conclusion, Cichlid fish species in Damietta Branch of River Nile are omnivorous, and did not consume food at random but have the ability to select and choose the preferred food stuff even during different seasons. These seasonal variations in preferred food makes the intraspecific competition between these species very low.

Trophic Interactions between Two Cichlid Species in Shatt Al-Arab River, Iraq

“…This may be attributed to the effect of low temperature on the ability of fishes to feed in the cold season. Similar results were obtained by Khallaf & Alne-na-ei (1987) about C. zillii in a Nile canal, Egypt; Shalloof et al (2009) about C. zillii in the Damietta branch of the river Nile, Egypt; Salah (2015) about O. aureus in Chybaish marsh, Iraq; Khalifa (2017) about O. aureus in Tigris river, Iraq and Mohamed & Al-Wan (2020) about C. zillii in the Garmat Ali river.…”

“…However, da Silva et al (2012) found that the high values of dietary overlaps between fish species in the Itiz river, Brazil referred to the food resource partitioning among fish species, and were associated with the abundance of these ingredients through the importance of vegetation, which is a source of conservation of the fish assemblage in the river. Shalloof et al (2009) stated that cichlid fish species did not consume food at random, but have the ability to select and choose the preferred food stuff even during different seasons. These seasonal variations in preferred food make the intraspecific competition between these species very low.…”

Feeding of European Pilchard, Sardina pilchardus (Walbaum, 1792) in Derna Coast, Eastern Libya

“…This may be explained by the fact that during spawning, the fish had fully occupied abdominal cavity with the ripe gonads and empty stomach. The synchronization of the period of poor feeding activity with spawning season has been reported for other fish species (Shalloof and Khalifa, 2009). Diet composition of S. pichardus revealed that they usually feed at the surface as indicated by their planktonic stomach contents.…”

Trophic relationships among fourteen native and non-native fish species in the Shatt Al-Arab River, Iraq

“…The results revealed that C. zillii was a highly specialized feeder, while Shep et al [63] considered C. zillii as generalized feeder in Ayamé Lake, Côte d'Ivoire6 Shalloof et al [64] stated that Cichlid fish species did not consume food at random but have the ability to select and choose the preferred foodstuff even during different seasons.…”