300520 VO Aquatic neozoans in freshwater (2007W)

The number of invading species in several taxonomic groups has increased successively during the last decades. The diversity of these is highest in Crustacea and Mollusca. The lecture is listing the invading species, identifies the donation areas (e.g. the Ponto-Caspian Basin and North America being most important), the invasive corridors (southern, central and northern corridor) and the vectors (canals and vessel traffic, fisheries and aquaculture, aquarists, pet shops, etc.). Invasive species have special life history traits in common compared to their native relatives and are commonly classified as r-strategists. Invasive species have both economical and ecological impacts, the latter reaching to species replacement, changes in food webs up to deteriorations of ecosystems. In most cases control of established populations is extremely difficult and eradication hardly to realize (except in isolated bodies of water). There are several proposals for reducing the problem in future: legislation and enforcement, public awareness for special groups of interest (e.g. anglers, aquarists) and the general public as a whole, ballast water treatment, etc.
The lecture concentrates primarily on Austria and Europe, but also gives examples from other regions (North America, Africa, etc.) when appropriate.