DISTRIBUTION AND SEASONAL ABUNDANCE OF FRESHWATER SNAILS IN SOME EGYPTIAN WATER COURSES

Document Type : Original Article

Authors

Department of Environmental Research and Medical Malacology, Theodor Bilharz Research Institute, P.O. Box 30, Imbaba, Giza, Egypt.

Abstract

Mollusca play important role in the public and veterinary health and thus need to be study their distribution continuously. The present clarified the distribution and seasonal abundance of freshwater snails in the River Nile branches, main canals and some drains in eight Egyptian governorates during eight successive seasons. The highest percentage of snails' abundance in the River Nile was 33.6, 23, 22.1 and 20.8 % for Succinea cleopatra, Lanistes carinatus, Lymnaea natalensis and Cleopatra bulimoides snails, respectively. While Damietta and Ismailia canals were the mostly infested by snails in spring, Giza canals, Damietta branch and River Nile was in summer. During the whole study, the distribution of Lnatalensis was larger than Bulinus truncatus and Biomphalaria alexandrina. Results of correspondence analysis (CA) showed a good relationship between snail species and physical parameters explained 94.77, 94.12, 91.80 and 95.35% of variance in temperature, pH, conductivity and dissolved oxygen, respectively. Values of physical parameters were approximately the same for all stations. In spite of the conductivity was high 1200μmhos/cm in drains, other stations ranged from 200 to 800μmhos/ cm.

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