Streams of Tatra National Park (southern Poland) belong to the basin of the Dunajec, flowing mostly Tatra valleys. Their beds are a small width and length not exceeding 15 km; with declines of up to 40% and the turbulent flow of water. Fish fauna of streams is poor. It is recognized that  in the waters of TNP 6 fish species occurs: Salmo trutta m. fario, Cottus poecilopus, Phoxinus phoxinus, Thymallus thymallus (periodically dwelling) and Salvelinus fontinalis and Oncorhynchus mykiss (alien species). In the park there occurs also probably Cottus gobio.

The aim of the study was to determine the prevalence of Cottus poecilopus in the main streams of the Tatra National Park. Fishing research was conducted within the summer in June and July, and in the autumn, in September and October 2014 for fourteen streams.

The catches were  made with pulse fishing device (IUP-24),  in 3 positions in each of the streams, wading up stream. During fishing habitat was characterized by noting the speed of the current, the presence of obstacles and hiding places for fish, width, type and size of the bottom substrate, the presence of wood and shade. The beginning and end of each transect was described by the geographic coordinates using a Garmin GPS device. Based on the geographical coordinates the project was created in GIS (using ArcMap software 9.3.1) and determined the amount of occurrence of fish above sea level. In the course of fishing three species of fish were found: Cottus poecilopus, Salmo trutta m. fario and Salvelinus fontinalis. In the studied streams Cottus gobio was not found. The most numerous Cottus poecilopus were represented, a total of 485 units in 12 streams. The highest position where he performed the genre was Chochołowski Potok (1077.3 m above sea level).

DOI: https://doi.org/10.3846/enviro.2017.032