MSc Student
Advisor: Thomas Schwaha

Unit for Integrative Zoology, Department of Evolutionary Biology
University of Vienna

Abstract

Freshwater Bryozoa belong to Phylactolaemata or in some cases to ctenostome Gymnolaemata. Although they occur worldwide, they are only poorly investigated. In Europe only approximately 19 species are known, 12 of them recorded for Austria. These small, sessile filter feeders are often misidentified as mud or moss and in standard limnological investigations they are often neglected. In addition, Phylactolaemata colonies do not occur all year round in Europe due to unfavorable conditions and therefore form dormant stages called statoblasts to overwinter. In Austria mostly major river-areas like the Danube, March and Thaya or some lakes and ponds in the eastern part of Austria were investigated. Water bodies influenced by moor were so far not or only insufficient investigated in Austria. Only neutral to weak alkaline (pH = 7.40-8.45) water bodies were studied, whereas moor water differs to river water because of acid pH and oligotrophy. The influence, however, of such different environmental conditions on bryozoan species diversity remains unknown. The impact of water parameters on the abundance and distribution of freshwater Bryozoa is not completely understood. The aim of this thesis is to investigate bryozoan species composition in ponds and lakes influenced by moor in the upper Woodquarter in Lower Austria. Therefore, petri dishes are placed in water bodies as settlement substrates and regularly checked for bryozoan colonies. Samples will be taken from these colonies and identified via their statoblasts. Additionally, water parameters of the investigated study sites will be tested and compared to assess their impact on the occurring bryozoan species.