Sandimirov S.S. Catalogue of lakes in the Russian, Finnish and Norwegian Border Area. Finland, Jyvaskyla: Kopijyva Oy, 2008.

Vendace.The vendace inhabiting the pelagic zone of Lake Kuetsjarvi were of small size (9.3 - 13.6 cm, 6-19 g).The mean values were 10 g and 11.0 cm. Grayling. According to our data grayling was the most common in Lake Mellalom- pola. In the other water bodies it was caught only occasionally. Burbot. There were only single catches of this fish. Analysis of some population parameters in the water bodies at various distances from the smelter indicate changes in the fish populations. The decrease in the age, size and maturity ranges of the fish populations in the polluted water areas (Lake Kuetsjarvi) indicates poor water quality. The whitefish populations are characterized by a small number of age groups, rejuvenation of the populations, and maturation at an early age. Fish p a th o lo g y According to the analysis of pathological changes in whitefish in the lakes, on the whole, disorders in the liver, kidney, gonads and gills were the most common. The fre­ quency of pathologies of the liver and kidney tended to increase throughout the whole study period. Fish pathologies were frequently encountered in the water bodies located both in the vicinity and at greater distances from the pollution sources. The intensity and characteristics of the fish pathologies observed in the water bodies exposed to dif­ ferent levels of air borne pollution were similar. In the water bodies in the background region (Stuorajavri) and in small forest lakes (Kochejaur, Virtuovoshjavr, Aittojarvi, Kantojarvi, Mellalompola and Suovaselkajarvi), of organ abnormalities was common, as was the case in the water bodies located in the vicinity of the pollution sources. The most frequently occurring disorders of whitefish were connective-tissue expansions. This may reflect the increasing load ofNi on the water bodies, which causes the devel­ opment of this particular type of pathology. H eavy m etals in £sh Concentration of Cu in liver (цд/д dry weight) Copper. Comparison of the Cu concen­ trations in whitefish liver in the different lakes showed that the mean Cu concen­ trations in liver in the strongly polluted water body (Lake Kuetsjarvi) were com­ parable to those in the small forest lakes, and sometimes even exceeded them (Lake Suovaselkajarvi). The Cu concentration in liver was at its lowest in Lake Stuorajavre (Fig. 85). Nickel. The Ni concentrations in white- fish kidney from Lake Kuetsjarvi (average 22.72 pg/g dry wt) were higher than those in the other water bodies (Fig. 86). The whitefish in the small forest lakes (Vir- tuovoshjaur and Aittojarvi) had mean Ni concentrations of 6.50-6.60 pkg/g dry wt. In the other water bodies, including the background region (Stuorajavri), the Ni concentrations did not exceed 5 pg/g dry wt. Fig. 85. Copper concentrations in the liver ofsparsely rakered whitefish in the studied lakes. Fig. 86. Nickel concentrations in the kidney of sparse­ ly rakered whitefish in the studied lakes. Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea 139