Sandimirov S.S. Assessment of the habitat conditions for the freshwater pearl mussel Margaritifera margaritifera (l.) In the headwaters of major rivers of Murmansk region. Conservation of freshwater pearl mussel Margaritifera margaritifera populations in Northern Europe. Proceedings of the International Workshop. Karelian Research Centre of RAS. 2010, p. 29-34.

CONSERVATION OF FRESHWATER PEARL MUSSEL MARGARITIFERA MARGARITIFERA POPULATIONS IN NORTHERN EUROPE Analysis o f water mosses. Samples were collected from the river sections with the highest percent cover of mosses: 70-100%. Determination of the species composition and description of the ecological characteristics of the mosses were carried out following Garibova et al. (1978), Abramova et al. (1961), Abramova &Volkova (1998), Ignatov & Ignatova (2003, 2004). Fig. 1. Locations of the surveyed sections in the headwaters (Kitsa River - Umba River basin; Tsaga River - Voron’ya River basin; Pana River - Varzuga River basin) Ichthyological surveys. Determination of the fish species composition was conducted in August- September of 2008. Special focus was on detailed assessment of potential spawning and nursery areas of S. salar and S. trutta. The surveys were conducted using portable equipment manufactured by Ing. S. Paulsen FA-3 (Trondheim, Norway) as in Amundsen et al. (2004), Bohlin et al. (1989), Reynolds (1996), Young and Schmetterling (2004). The density of salmon and trout parr was estimated through 30