Survey of angler's internet posts confirmed the occurrence of freshwater fishes of the genus Ictiobus (Rafinesque, 1819) in natural waters of Czechia

The information regarding the fish species occurrence in rivers and lakes depends on the quantity and quality of ichthyofaunal surveys. Non-native buffalo fishes, Ictiobus cyprinellus and I. niger (Catostomidae) were introduced to pond aquaculture in the 20th century but since that time they have never been recorded from the natural environment in Europe. Forensic analysis was performed using online data from Czech anglers websites to test whether these fishes were ever caught. In total 13 records were obtained but only 3 were verified in terms of species identification, locality and date. The found records are scattered throughout the area of Czechia and they are without an obvious distribution pattern. The analysis of online fishing web sites can be considered a suitable source of additional information on the occurrence of fishes.