aLomonosov Moscow State University Biological Faculty, Department of Ichthyology
Leninskie Gory, 1, Moscow, 119234 Russia
bLomonosov Moscow State University Faculty of Geography, Department of Cartography and Geoinformatics
Leninskie Gory, 1, Moscow, 119234 Russia
cSevertsov Institute of Ecology and Evolution, RAS
Leninskii Prosp., 33, Moscow, 119071 Russia
dFederal Research Institute of Fisheries and Oceanography (VNIRO)
V. Krasnoselskaya st., 17, Moscow, 107140 Russia
ePskov Division of GosNIORKh
Gorkogo st., 13, Pskov, 180007 Russia
*e-mail: kriksunov@mail.ru
**e-mail: svchistov@mail.ru
Inter-annual and intra-seasonal patterns of spatio-temporal dynamics of main commercial fishes from Pskov Lake – one of the most productive water bodies in North-West Russia – are investigated. The results of cartographic analysis are presented on summer–fall fish distributions in the lake. As input data, the results of trawl surveys conducted in years differing by water level (2003, 2006, and 2008) were used. Initial data were aggregated into the tables of attributes which contain the information on trawling dates, trajectories, duration, average speed, water temperature, and catch specific and size composition. These tables were used for mapping the spatial distribution of seven fish species (bream, pike-perch, roach, perch, white bream, burbot, and ruff). For roach, pike-perch, bream, pike, and perch, cartographic estimates of abundance are obtained. The attempt has been made to assess the reproduction efficiency of several fish species (pike-perch, perch, and pike) on basis of the analysis of their abundance changes from spring to autumn. For pike-perch, maps of spatial distribution are made up, which account for size composition of the population. Discrepancy in localization of different age groups in different seasons, along with their moving patterns, is ascertained. Patterns of fish spatio-temporal dynamics are matched with available hydrological characteristics.
