engleski

Long-term changes to ichthyofauna composition of Butoniga reservoir

In the 19 year history of the Butoniga reservoir lake, ichthyofauna of the reservoir has been studied for seven years. Over time, changes were observed in the composition of the fsh community. During the frst studies in 1997, the newly formed reservoir lake was inhabited with 9 fish species: Leuciscus cavedanus, Leuciscus sp., Gobio gobio, Alburnus albidus, Tinca tinca, Barbus plebejus, Phoxinus phoxinus, Padogobius boneli and Anguilla anguilla. The only true predator in the lake was Eel. The lake was of a cyprinid character with White Cub and Adriatic Barbel as the dominant species. In 1999, the initial species composition of the lake was altered with the appearance of Carp, Prussian Carp and Pike, species interesting to sports fishermen who had illegally stocked the lake with them. The species composition continued to change and in 2001, Pikeperch was found in the lake. This species is continually growing in abundance, with a decreasing share of total abundance of Carp and Prussian Carp, species which stir up lake silt thus increasing trophic processes. With growing Pikeperch numbers, the Tench population also is constantly on the rise. Parallel to these processes, the indigenous species Adriatic Barbel, Gudgeon, Leuciscus sp. and Minnow have disappeared from the fish community. Over time, trophic processes and various ecological impacts have altered the ichthyological structure. The most important regulators of the fish community are: temperature and water quality, water holding times in the reservoir and fluctuation of the lake’s surface.

Ichthyofauna; Butoniga reservoir

nije evidentirano