Fishes: Austria's lakes (approx. 32,000 hectares), ponds (approx. 3,000 hectares) and flowing bodies of water (approx. 18,500 km) once held circa 60 species of fishes and two species of cyclostomes. Five fish species have become extinct. The Kessler groundling was found in Austria in 1988 for the first time, the golden loach in 1989. Several fish species have been brought to Austria for fishing purposes. The introduction of fish species foreign to Austria and the excessive cultivation of any one indigenous species have presented a serious threat to indigenous fish populations.
Examples: salmon-like fish (trout, lake trout, brook trout, Danube salmon (huchen)); carp fish (scaly carp, mirrored (shining) carp, and leather carp, including the barbels, tench and 29 other species); perch (zander, barbel, Danube ruffe, streber, zingel); sheath-fish (catfish) (wels and brown bullfish (catfish); common eel, pike, grayling, loaches (pond loach (thunderfish), or European weatherfish, loach, spined loach, or groundling).