Gastropod Assemblages Associated with Habitat Heterogeneity and Hydrological Shifts in Two Shallow Waterbodies

We aimed to determine the effects of water level and habitat heterogeneity on gastropod fauna in littoral zone, differentiation functional feeding guilds (FFG) gastropods. Two periods were analyzed: 2012 (low level, LWL) 2013 (high HWL) zone two shallow waterbodies (Sutla backwater, NW Croatia). Waterbody S1, covered with Ceratophyllum demersum, was sampled macrophyte stands, benthal area, while waterbody S2, without macrophytes, only area. It observed discovered that among stands gastropods significantly more abundant during LWL. The same trend area S2. In contrast, abundance higher S1 HWL. Comparing waterbodies, ten times than most species Gyraulus parvus, which accounted for 51–92% macrophytes 86% adjacent benthic zone. Among FFG groups, grazers (particularly those gymnamoebae rotifers) had largest proportion, followed by shredders small pieces macrophytes. our research, we indicate important role microhabitat diversity submerged as a rich food source safe shelter from predators.