The relationship between aquatic macrophytes and some gastropoda (snails) in the lower reaches of Hammar marsh

Abstract

This study was carried out during 2011-2012 to evaluate the preference of some freshwater snails to specific macrophytes than others. Snails were collected from different aquatic plants; Ceratophyllum demersum, Potamogeton crispus, Salvinia natans,and Hydrilla verticillata at four stations. The presence of these plants was affected by the water temperature, they almost disappear in winter leading to low snail numbers at that season. Eight snail species were found at the study area; Bellamya bengalensis (Lamarck, 1822), Bithynia hareerensis Glöer, and Nasser, 2008 ,Gyrauluse hrenbergi (Beck, 1837), Melanoides tuberculata (Müller, 1774), Melanopsis nodosa Férussac, 1823, Physlla acuta Draparnaud, 1805, Radix auricularia (Linnaeus,1758), Theodoxus jordani (Sowerby, 1832). Statistical analysis shows a significant differences (P<0.05) between macrophyte's snails number, C. demersum and H. verticilata was the most preferred macrophyte in this study, while S. natanus recorded no occurrence of snails.