Water beetle distribution along a perennial distance gradient in an intermittent stream from the Mediterranean part of Montenegro

Abstract

In this study, we examined the impact of an unstable hydrological regime (floods and seasonal drying) on water beetle fauna after a drought period, in an intermittent stream in the Mediterranean part of Montenegro. Aquatic beetles were collected between November 2009 and May 2010 from three intermittent sites along the Rimanic stream at different distances from the perennial part (DP), using quantitative sampling methods. We predicted that water beetle assemblages would vary in structure and composition along DP gradients. Total abundance, taxa richness, main faunal groups and proportion of adults and larvae were assessed in order to describe the changes in the water beetle assemblages. The water beetle fauna in the studied sites recovered slowly from the drought periods in terms of both total abundance and taxa richness. Analysis of similarity (ANOSIM) showed no significant changes in community structure between the sites, but revealed changes in terms of date (Rho = 0.403).