Linear Growth of Sparsely Rakered Whitefish Coregonus lavaretus (Coregonidae) of the Imandra Lake (Murmansk Oblast) / Zubova E. M., Kashulin N. A., Terent’ev P. M. [et al.] // Journal of Ichthyology. – 2016. - Vol. 56, №. 4. - P. 588–599

ISSN 0032-9452, Journal ofIchthyology, 2016, Vol. 56, No. 4, pp. 588—599. © Pleiades Publishing, Ltd., 2016. Original Russian Text © E.M. Zubova, N.A. Kashulin, P.M. Terent’ev, D.B. Denisov, S.A. Val’kova, 2016, published in Voprosy Ikhtiologii, 2016, Vol. 56, No. 4, pp. 463—473. Linear Growth of Sparsely Rakered Whitefish Coregonus lavaretus (Coregonidae) of the Imandra Lake (Murmansk Oblast) E. M . Zubova*, N . A. Kashulin, P. M . Terent’ev, D. B. Denisov, and S. A. Val’kova Institute o fIndustrial Ecology Problems o f the North, Kola Scientific Center, Russian Academy o fSciences, ul. Fersmana 14A, Apatity, 184209 Russia *e-mail: zubova@inep.ksc.ru Received August 26, 2015 Abstract—This paper studies the properties of linear growth in sparsely rakered whitefish Coregonus lavaretus in the stretches of the large subarctic Imandra Lake, which are characterized by the diversity of habitat con­ ditions and anthropogenic stress levels. The groups of sparsely rakered whitefish that are confined to different areas of the lake are marked out based on the properties of growth, trophic status, and anthropogenic stress intensity. A direct relationship of the linear growth in whitefish with the age of sexual development and tro­ phic level of its habitats is found. Keywords: sparsely rakered whitefish Coregonus lavaretus, linear growth, trophic level, anthropogenic pollu­ tion, Imandra Lake DOI: 10.1134/S0032945216040172 INTRODUCTION Knowledge of the mechanism of fish growth regu­ lation and identification of the factors that determine its pace enable the use of growth parameters in the bio­ indication of the environmental situation, make it possible to forecast the fish productivity of reservoirs (Nikol’skii, 1974; Kuznetsova, 2003), and are the basis for the development of the principles for rational use and protection of fish resources, in particular, white- fish (Coregonidae). Due to its biological properties, the whitefish Coregonus that is widespread in the res­ ervoirs of the Murmansk oblast has been used for many years as a test object of ichthyologic monitoring (Moiseenko, 1983, 1991, 1997, 2000, 2002, Lukin, І995; Kashulin et al., 1999; Moiseenko and Lukin, 1999; Kashulin, 2004). The catchment area of the Imandra Lake concen­ trates large industrial enterprises of the region (mining and processing, metallurgical, energy, and other enterprises) that negatively affect the state of the water environment. In this regard, this reservoir remains important for fishery (Lukin et al., 2006; Reshetnikov et al., 2011). Earlier, under the conditions of intensive anthropogenic load (1983—1992), the whitefish of the Imandra Lake was registered to have two alternative life strategies: the former was characterized by the decelerated growth from the first years of life, delay in maturing, and frequent gaps in spawning; the latter featured the early maturing at a small size and reduc­ tion of lifetime (Moiseenko, 1997, 2002; Antropogen- nye modifikatsii ..., 2002). Under modern rapidly changing habitat conditions, the dependence of changes in the parameters of growth in whitefishes of Northern Fennoscandia on environmental factors have no t been studied enough. The goal of the work is to study the linear growth of whitefish at the Imandra Lake depending of hydro­ chemical and hydrobiological factors. MATERIALS AND METHODS The growth of whitefish was studied within the complex investigations of a large pond in the Mur­ mansk oblast (Imandra Lake (880 km2) in the White Sea basin). The lake consists of three largely indepen­ dent stretches—the Bolshaya, Yokostrovskaya, and Babinskaya Imandra stretches, which are intercon­ nected by narrow straits and located in the gradient of load from pollution sources (Fig. 1). The northern Bolshaya Imandra stretch is the most polluted part of the lake; effluents from the Olkon, Severonikel, and Apatit mining plants and utility fluids from the cities of Monchegorsk, Kirovsk, and Apatity come here. The southern Babinskaya Imandra stretch is the lake area that is most distant from the pollution sources. Waters from the two former stretches are mixed in the Yokostrovskaya Imandra stretch, and the flow from the lake through the Niva River takes place (Antropo- gennye modifikatsii..., 2002). Fish were caught by standard sets of stake gill nets made of nylon monofilament with a length of 25 m, height of 1.5 m, and mesh size of 10—60 mm, which 588