Species composition of ichthyofauna of the Kuibyshev reservoir

Data on species composition of ichthyofauna of the Kuibyshev reservoir for its period of existence (1957–2012) are presented. The list of fish of the reservoir compiled on the basis of materials of studied of recent years with consideration of new taxonomic revisions and reports (13 orders, 19 families, 46 genera, and 58 species) is cited. For the period from the moment of formation of the reservoir, its ichthyofauna has been supplemented by 17 new species, nine of which have formed self-reproducing populations.     

Occurrence of Cyclotella ambigua Grunow (Bacillariophyta) in the Kuibyshev Reservoir

The long-term study (1989–1995) of phytoplankton from the Kuibyshev Reservoir aided by the scanning electron microscopy revealed a salt water representative of centric diatoms Cyclotella ambigua Grunow, new for the Volga River. Morphological features of the frustule including elements of valve ultrastructure (location and structure of central and marginal fultoportulae, rimoportula, striae) are studied. The similarity and difference from other species of the genus, C. exigua Håkansson, C. striata (Grunow) Grunow, C. scaldensis Muylaert et Sabbe, and C. meneghiniana Kützing, are shown. Based on original and literature data, the extended diagnosis of C. ambigua is given along with the examination of the ecology and distribution of this species, little known in Russia and abroad.     

The seasonal and interannual dynamics of centric diatoms in the Kuibyshev Reservoir

Samples of centric diatom algae from the plankton of the Kuibyshev Reservoir collected in years with different hydro-meteorological conditions (1989 and 1990) have been studied using light and scanning electron microscopy technique. Twenty-nine species, varieties, and forms of Centrophyceae, including two species new for the algoflora of the Volga River plankton, have been discovered. The main body of the dominant species is formed by algae with a high frequency of occurrence. The seasonal dynamics of abundance is characterized by spring peaks formed mainly by small-celled algae and less regular late fall maximums formed by large-celled forms. During these periods the abundance of Centrophyceae determines the level of phytoplankton development in general. Under stable species richness of algae and seasonal dynamics of their abundance, the average number of Centrophyceae during the hot and low-water year of 1989 reached 3.6 million cells/l; during the cold and high-water year of 1990, there were twice as few: 1.9 million cells/l.     

DNA Polymorphism of Percidae population structure in the Kuibyshev water reservoir of Russia

The depletion of fish stocks in the Mediterranean suggests that restocking may be a useful approach for restoring fisheries. In this paper we consider the potential for using derelict salt pans at Tarquinia (50 miles north of Rome) to rear fish for restocking in adjacent coastal areas. We discuss candidate species for stock enhancement, ways of minimizing stress in the capture of broodstock, genetic monitoring of wild catches, various aspects of operational restocking (release stage of larvae or juveniles, etc ) and suggest approaches for evaluating results. Finally, we provide an economic and financial analysis of investment costs and likely benefits for different scenarios, and guidelines for a restocking policy that may be implemented by public authorities.     

Long-term (30 years) dynamics of Chironomidae (Diptera) fauna in the Kuibyshev water reservoir associated with eutrophication processes

Benthos investigations were carried out in the channel and flood-plain of the Kuibyshev water reservoir during 1958–1985. Hydrobiological monitoring data obtained at 12–16 stations in all Deeps excluding littoral areas are discussed. In 1987–1900 benthofauna distribution was also studied at the Priplotinny Deep. An increase of the reservoir trophic state is reported. The observed trend was an increase of the total benthos biomass. Changes in both species and trophic structure of the chironomid community due to the eutrophication problem are discussed.     

The spatial structure and interrelation of plerocercoids of Digramma interrupta (Cestoda, Ligulidae) and the bream (Abramis brama) in the Kuibyshev reservoir

The character of the distribution of the plerocercoid D. interrupta in the bream Abramis brama from the Kuibyshev water reservoir was studied. The spread of the parasites in A. brama population is of complex character and changes with the increase of fish body length. The factors affecting the maintenance and regulation of the relationships in the host-parasite system (size composition of fishes, peculiarities of the host's genotype, values of occurrence of different numbers of the parasites, variability of plerocercoids) are discussed.     

Population Characteristic of the Volga zander <Emphasis Type="Italic">Sander volgense</Emphasis> (Percidae) in the Kuibyshev reservoir

The analysis of the size composition, age structure, linear growth, and fecundity of the Volga zander Sander volgense has been performed in the Kuibyshev reservoir. To date, the growth rates of the species have decreased slightly compared to the 1970s. Over the period from 2000 to 2013, catch volumes of Volga zander tended to increase.     

Features of biology of the round goby <Emphasis Type="Italic">Neogobius melanostomus</Emphasis> (Perciformes,Gobiidae) in waters of Kuibyshev Reservoir

Based on materials of 2003–2005, the size-age composition, dates of reproduction, distribution, as well the qualitative and quantitative composition of the food of the round goby Neogobius melanostomus in the coastal part of Kuibyshev Reservoir are considered. It is shown that the round goby prefers coastal parts of the reservoir with depths to 10 m and rocky grounds and that its main food are mollusks of the genus Dreissena.     

Some features of biology of big-headed goby <Emphasis Type="Italic">Neogobius gorlap</Emphasis> (Perciformes,Gobiidae) in waters of the Kuibyshev Reservoir

On the basis of materials of 2003–2005, the size-age composition, dates of reproduction, as well as qualitative and quantitative food composition of big-headed goby Neogobius gorlap in the coastal part of the Kuibyshev Reservoir are considered. It is shown that big-headed goby prefers coastal parts of the reservoir with depths up to 2.5 m and rocky, sandy-slimy grounds; the bulk of its feeding consists of crustaceans.     

Growth,size-age structure of catches and reproduction of the Volga zander <Emphasis Type="Italic">Sander volgensis</Emphasis> (Percidae) in the upper part of the Volga stretch of the Kuibyshev Reservoir

Conditions of reproduction, size-age structure of catches, and the growth of the Volga zander Sunder volgensis in the upper part of the Volga stretch of the Kuibyshev Reservoir from 2002 to 2007, as well as its fishery in this water body, are considered. A decrease in catches of the proportion of large elder age groups of the Volga zander in the period of destabilization of the reservoir ecosystem, as compared to the phase of its relative stabilization from the 1970s to the 1980s, and a decrease in the commercial catch were established. Besides, retardation of its growth in connection with the deterioration of the ecological situation is observed, but the average level of reproduction is retained, which at the organization of rational fishery can lead to the restoration of the Volga zander stock.