Shalloof, K., El-Kasheif, M., Authman, M. (2009). Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt. Egyptian Journal of Aquatic Biology and Fisheries, 13(4), 49-66. doi: 10.21608/ejabf.2009.2044
Kariman Shalloof; Midhat El-Kasheif; Mohammad Authman. "Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt". Egyptian Journal of Aquatic Biology and Fisheries, 13, 4, 2009, 49-66. doi: 10.21608/ejabf.2009.2044
Shalloof, K., El-Kasheif, M., Authman, M. (2009). 'Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt', Egyptian Journal of Aquatic Biology and Fisheries, 13(4), pp. 49-66. doi: 10.21608/ejabf.2009.2044
Shalloof, K., El-Kasheif, M., Authman, M. Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt. Egyptian Journal of Aquatic Biology and Fisheries, 2009; 13(4): 49-66. doi: 10.21608/ejabf.2009.2044
Food and Feeding Habits of Three Cichlid Species Inhabiting Damietta Branch of the River Nile, Egypt
1National Institute of Oceanography and Fisheries, 101 Kaser El- Eini St. Egypt.
2Department of Hydrobiology, National Research Center, Dokki 12622, Giza, Egypt.
Abstract
The 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.