Habitat Richness and Seasonal Occurrence of Large Branchiopods (Crustacea: Branchiopoda) in the Areas of the Ramsar Site “Bardača Wetland” and the Donja Dolina in Bosnia and Herzegovina

Abstract

Multi-year studies were carried out in the "Bardača Wetland" and Donja Dolina areas in northern Bosnia and Herzegovina. Nine taxa of large branchiopods were found at the surveyed sites. All registered taxa show a continuous seasonal distribution with a partial overlap of temporal occurrence. Based on the environmental characteristics of the water body, the cluster analysis separated two groups of habitats: 1) the zone of flooded pastures around the Sava River and 2) small ponds of different depths, which mainly occur in the pastures outside the floodplain. Within each cluster, several groups of habitats were distinguished. The results of the Spearman correlation analysis showed no correlation between the number of species and the individual environmental parameters. A clear seasonal distribution of taxa can be observed: three taxa occur in late winter and early spring, one in mid-spring and five were reported only in late spring. Triops cancriformis was recorded for the first time in Bosnia and Herzegovina. This study suggests that an plentifulness of environmental factors and specific seasonal fluctuations favour species richness rather than single environmental parameters in individual habitats. Due to the study area's high natural and cultural-historical value, "Bardača" and Donja Dolina should be continuously monitored and protected.