Brown and brook trout populations in the Tatra Mountain lakes (Slovakia, Poland) and contamination by long-range transported pollutants

Fish living in the extreme conditions of the Tatra Mountain lakes were evaluated from a biological point of view as well as an important biomarker of long-range transported pollutants. In Velké Hincovo pleso and in Morskie Oko, specimens of brown trout (Salmo trutta) of extraordinarily advanced age were found (ages of 18+ and 17+ years, respectively). The capture of a 17+ year-old brown trout in Morskie Oko (2400 g, 540 mm) indicated the presence of the so-called ferox life strategy. The growth of brook trout (Salvelinus fontinalis) was faster than the growth of brown trout in the younger year classes, and while the growth of brook trout stopped after the age of 5+, the growth of brown trout continued. Concentrations of long-range transported pollutants (HCHs, HCB, DDTs, PCBs, PBDEs, and trace metals) in the Tatra Mountain fish were mostly associated with fish age, body weight and length, type of fish tissue, and lake altitude. Persistent organic pollutants (POPs) in fish muscle were dominated by PCBs 138, 153, 180, and p,p'-DDE. Conversely, PBDEs concentrations ranged at substantially lower levels compared to other POPs. Altitude correlated significantly with concentrations of a-HCH, HCB, p,p'-DDT, p,p'-DDE, and with PCBs 28 and 52. The highest contents of trace metals were found in kidney and liver samples, with higher concentrations in Velké Hincovo pleso than in Morskie Oko. The overall highest trace metal concentration levels were found for Fe, Cu, and Zn. In comparison with other European mountain lakes, the Tatra Mountain lakes are among the more contaminated. © 2015 Institute of Zoology, Slovak Academy of Sciences.

This research was financially supported by two consecutive projects: EMERGE (EVK1-CT-1999-00032) and EURO-LIMPACS (GOCE-CT-2003-505540). We also thank the Ministry of the Environment of the Czech Republic and the Grant Agency of Czech Republic for the grant 14-09231S, which enabled the final processing of results. We also sincerely thank to Peter Bitušík, Martin Blažo, Martin Černý, Barend L. van Drooge, Václav Fomín, Radek Šanda, Ingrid Vives, and Jasna Vukić for their assistance in field work and to Marie Hynštová for creating the GIS map.

Peer reviewed