Temporäre Gewässer und ihre naturschutzfachliche Bedeutung

Temporary water bodies and their conservational significance.
Temporary ponds are important, but often neglected habitats for many endangered species. Size and hydroperiod determine the occurrence of aquatic species, e.g. mosquito larvae, large branchiopods and amphibians. Sixteen species of the so-called primeval shrimps (Crustacea: Branchiopoda) were docu- mented in Austria: almost a quarter of the European species and two thirds of the European genera are present on less than 1% of the continental land mass, which implies high national responsibility for this taxon.
Amphibians are considered to be the most threatened vertebrates worldwide, mainly due to habitat loss. Twelve of the 21 Aus- trian Amphibian species occur in the Morava and Dye flood plains along the borders between Austria and Slovakia or the Czech Republic, respectively. This exceptional amphibian biodiversity is due to the morphological and hydrological variability of tem- porary waters and river inundations.
Astatic water bodies are essential stepping stones for migratory birds, as documented herein for the Morava and Dye flood plains. Forty-one wading bird species were documented along the Morava and Dye rivers, 36 of them at „vogel.schau.plätze“, a former sedimentation basin of the sugar refinery near Hohenau/March, Lower Austria.
Main threats to temporary pools are intensive agriculture and urbanization, leading to physical destruction, eutrophication and hydroperiod changes. Proper information of responsible governmental bodies, politicians and opinion leaders seems to be crucial for the conservation of a maximum environmental diversity of temporary ponds.