Benthic assemblages of wetlands invaded by Tarebia granifera (Lamarck, 1822) (Caenogastropoda: Thiaridae) in the iSimangaliso Wetland Park, South Africa

Abstract

Tarebia granifera is a freshwater/estuarine gastropod invading many tropical and sub-tropical areas around the world. This snail is native to southeast Asia and was accidentally introduced into South Africa during the last decade. The current study investigated shallow-water benthic assemblages of different invaded and uninvaded localities across locations spanning a large range of environmental conditions in the iSimangaliso Wetland Park. Using a correlation-based approach, we found that native benthic assemblages were more closely associated with environmental conditions than with densities of T. granifera. However, there were significant negative correlations between T. granifera abundance and Shannon Diversity at two of the invaded locations. This alien species has successfully invaded, and become dominant in, different types of water bodies with different assemblage compositions and physico-chemical characteristics, ranging from freshwater ponds to saline estuaries and lakes. The current data set is presented as an essential baseline for future studies. It is recommended that future work focuses on specific localities, in order to determine if changes in diversity are driven by non-native species or by other disturbances (e.g., climate change).

Keywords:

• alien invasive species
• parthenogenetic
• biodiversity
• shallow-water

Acknowledgements

We thank the iSimangaliso Park Authority and Ezemvelo KZN Wildlife for supporting this project. Special thanks go to R. Taylor, S. Kyle, C. Fox and S. Mfeka for their invaluable assistance in the field. We would also like to give special thanks to Prof. W.M. Meyer and Prof. Steven Smith for their helpful advice and suggestions. Funding was provided by the National Research Foundation (NRF), The South African—Netherlands Research Programme on Alternatives in Development (SANPAD) and the World Wide Fund for Nature (WWF). This work is based on the research supported by the South African Research Chairs Initiative of the Department of Science and Technology (DST) and National Research Foundation (NRF) of South Africa. Any opinion, finding and conclusion or recommendation expressed in this material is that of the author(s) and the NRF does not accept any liability in this\enlargethispage{-1.5pt} regard.