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Vol. 19 (2016 year), No. 1, DOI: 10.21443/1560-9278-2016-1/2

Nikolaev A. M., Alekseev M. Yu.
Dynamics of feeding of 1+ hatchery-reared Atlantic salmon (Salmo salar L.) stocked into a tributary of the Kola River

The adaptation process of 1+ Atlantic salmon reared at hatcheries of the Murmansk region to life in a natural environment has been studied; the intensity of food consumption by salmon parr in the first two months after stocking into the Orlovka River (a tributary to the Kola River) has been determined in dynamics. A significant difference in quantitative and qualitative composition of food between reared and wild juvenile salmon has been found. Based on the analysis of the authors' and literature data a conclusion has been made that specific feeding behavior of reared juveniles can be related to the adaptation to keeping conditions at the farm

(in Russian, стр.0, fig. 0, tables. 0, ref 0, Adobe PDF, Adobe PDF 0 Kb)

Vol. 20 (2017 year), No. 2, DOI: 10.21443/1560-9278-2017-20-2

Nikolaev A. M., Alekseev M. Yu., Samokhvalov I. V., Legun A. G., Il'mast, E. N. Rasputina, Yu. A. Shustov N. V.
Distribution, feeding and growth of hatchery-reared Atlantic salmon (Salmo salar L.) parr stocked into rivers with various abiotic conditions

Within the research of efficiency of Atlantic salmon the artificial reproduction, feeding rate, distribution and growth of farm-raised one-year-old Atlantic salmon have been examined. The fish has been released into nursery areas with different hydrological characteristics located in the Rivers Kola, Umba, Srednyaya and Akkim in the Murmansk region. The observations have being conducted for 1–5 months since the moment of fish release. In natural habitat, juveniles rapidly distribute downstream and upstream regardless of water temperature, depth and current velocity. In all examined nursery areas adapting one-year-old juveniles prefer to stay at weak current sites close to the shore, hiding in the gravel. In all the cases farmed parr shows high feed rate, but qualitative composition of their food differs significantly from food composition of wild juveniles. Revealed peculiarities of adapting parr's distribution and qualitative food composition indicate the impact of long-term rearing at hatcheries on fish behavior. Growth rate of one-year-old juveniles is arcwise connected with fraction composition of gravel and the level of bottom fouling: the bigger bottom rocks are and the thicker the fouling is, the more intensive fish growth is. The revealed correlations have been described with equations of linear regression. Connections between juvenile growth and water temperature, current velocity and depth of the area have not been detected. The research outcomes could provide a basis for scientific advice for planning release sites and number of released one-year-old Atlantic salmon by hatcheries in the Murmansk region.

(in English, стр.10, fig. 3, tables. 5, ref 24, Adobe PDF, Adobe PDF 0 Kb)