ON THE INVASION OF THE GENUS MARENZELLERIA (POLYCHAETA, SPIONIDAE) REPRESENTATIVES INTO THE CASPIAN SEA BASIN

2021 ◽  
Vol 14 (3) ◽  
pp. 45-49
Author(s):  
A. V. Mikhailova ◽  
E. V. Popova ◽  
S. V. Shipulin ◽  
A. A. Maximov ◽  
I. S. Plotnikov ◽  
...  

In 2018, in the bottom fauna of the Caspian Sea, single specimens of a previously unknown species of polyhaetes were discovered. Since 2019, pelagic larvae of this species have been recorded in zooplankton samples. These worms are also found in the nutrition of migratory and semi-migratory fish species. According to morphological features, this polychaete species is identified as Marenzelleria arctia , an Arctic species dominating in the Gulf of Finland and probably invaded the Caspian along the Volga-Caspian invasion corridor.

2007 ◽  
Vol 16 (1) ◽  
pp. 135-137
Author(s):  
N.G. Bogutskaya ◽  
E.A. Dorofeyeva

The original description of Salmo spurius Pallas, 1814 is based on Pallas’s own material and the literature sources, which include at least two species-group taxa. A specimen from the Gulf of Finland, deposited at Zoological Institute, St. Petersburg, is designated as neotype of S. spurius. As result of this designation, the unused name S. spurius becomes a junior synonym of S. trutta trutta Linnaeus, 1758 and does not threaten the current nomenclature of trouts from the Caspian Sea basin.


Radiocarbon ◽  
1980 ◽  
Vol 22 (3) ◽  
pp. 662-675 ◽  
Author(s):  
Ingrid U Olsson

The reservoir effect of Scandinavian sea water has been determined by dating seals and whales killed well before man's impact on the natural 14C concentration became significant. The samples were collected at different places along the Swedish coasts and in the Gulf of Finland. They derive from ad 1657 or 1658, 1868, 1875, 1894, and 1906. The EDTA treatment of bones was used to obtain collagen free from contaminants.An elk, originating from ad 1881 was selected for comparison. A seal from ad 1899 from the Caspian Sea was also included in the investigation.All results have been normalized to δ13C = —25‰ vs PDB. The determinations yield values of the reservoir effect in agreement with earlier results obtained from shells and mammals. The final results are discussed in light of previous variations of 14C content in the atmosphere. Using a smoother curve, the reservoir effect is slightly smaller than was hitherto believed.An event thought to be of cosmic origin caused the count rate of both proportional and Geiger counters to increase significantly around December 4, 1978. The correction for this has been studied. The statistics for background, oxalic acid, and unknown samples, measured repeatedly after this correction, were as good as usual.


Author(s):  
Anna Viktorovna Mikhajlova

The article highlights the processes of lowering and raising the Caspian Sea level and its influence on the quantitative and qualitative characteristics of the aquatic bioresources, including zoobenthos. The development of macrozoobenthos in the Caspian Sea including the Northern Caspian is associated with various processes: chemical, physical and biological. The presence of macrozoobenthos determines the fish productivity in the sea, it is an integral part of the ecosystem of the northern part of the Caspian Sea. In this regard, the assessment of the composition and quantitative characteristics of bottom communities becomes important. One of the urgent tasks of modern hydrobiology is detecting the basic regularities in the biotic processes that affect the qualitative and quantitative changes in the aquatic organisms. This research is of a retrospective nature. On the basis of a long-term analysis of the dynamics of the species structure of bottom zoocenoses there have been revealed the changes in the macrozoobenthos of the western part of the Northern Caspian in the first and second periods of the sea level rise (1978–1988 and 1989–1995). Decreasing water salinity, increasing desalinated zones and areas with oxygen deficiency in the bottom horizon (in the extremely high-water years of 1990 and 1991) contributed to the significant changes in the quantitative and qualitative composition of the bottom fauna. From the first stage to the second there was recorded a decrease in the number and biomass of crustaceans and molluscs. The species Stenogammarus macrurus (G. O. Sars) and Stenogammarus similis (G. O. Sars), which are tolerant to the significant salinity fluctuations, as well as abra, which is resistant to oxygen deficiency were most abundant in the water complex with light salinity. Also, there has been considered the water content of the rivers of the Caspian basin and the type of soil as factors influencing changes in the concentration of macrozoobenthos.


2014 ◽  
Vol 50 (4) ◽  
pp. 3-14
Author(s):  
M. Ye. Makushenko ◽  
D. V. Kulakov ◽  
Ye. A. Vereshchagina

Author(s):  
Edward Vladimirovich Nikitin

Shallow coastal waters of the Volga river is a flooded feeding area for fish juveniles of nonmigratory fish species. There takes place annual downstream migration of fluvial anadromous fish species from spawning grounds of the Volga river to the Northern Caspian Sea. The most important factors determining the number and qualitative characteristics of fry fishes are the level of the Caspian Sea (currently having a tendency to the lowering), hydrological and thermal regimes of the Volga river. Researches were carried out in definite periods of time. In the summer-autumn period of 2012 fry fishes were presented by 19 species (13 of them were commercial species), which belonged to 9 families. The article gives data on all the commercial fish species. In the first decade of July the maximum number of fry fish was registered in the western part of the Volga outfall offshore - in box 247 (19.86 mln specimens/km2), in the eastern part - in box 142 (20.4 mln specimens/km2). The most populous were roach, red-eye, silver bream and bream; size-weight characteristics were better in the areas remoted from the Volga delta. In the third decade of July the quantitative indicators of fry fish on these areas decreased, size-weight characteristics greatly increased. In the second decade of October in the western part of the seaside there were registered increased pre-wintering concentrations of fish juveniles, their qualitative indicators increased, which is evidence to favorable feeding conditions in 2012.


2020 ◽  
Vol 45 (9) ◽  
pp. 607-614
Author(s):  
V. B. Popov ◽  
A. A. Sin’kevich ◽  
J. Yang ◽  
Yu. P. Mikhailovskii ◽  
M. L. Toropova ◽  
...  

2020 ◽  
Vol 324 (2) ◽  
pp. 262-272
Author(s):  
I.V. Doronin ◽  
T.N. Dujsebayeva ◽  
K.M. Akhmedenov ◽  
A.G. Bakiev ◽  
K.N. Plakhov

The article specifies the type locality of the Steppe Ribbon Racer. The holotype Coluber (Taphrometopon) lineolatus Brandt, 1838 is stored in the reptile collection of the Zoological Institute of the Russian Academy of Sciences (ZISP No 2042). Literature sources provide different information about the type locality. A mistake has been made in the title of the work with the original species description: the western coast of the sea was indicated instead of the eastern one. The place of capture was indicated as “M. Caspium” (Caspian Sea) on the label and in the reptile inventory book of the Zoological Museum of the Academy of Sciences. The specimen was sent to the museum by G.S. Karelin. The “1842” indicated on the labels and in the inventory book cannot be the year of capture of the type specimen, just as the “1837” indicated by A.M. Nikolsky. In 1837, Karelin was in Saint Petersburg and in 1842 in Siberia. Most likely, 1837 is the year when the collection arrived at the Museum, and 1842 is the year when the information about the specimen was recorded in the inventory book (catalog) of the Zoological Museum of the Academy of Sciences. In our opinion, the holotype was caught in 1932. From Karelin’s travel notes of the expedition to the Caspian Sea in 1832, follows that the snake was recorded in two regions adjacent to the eastern coast of the Caspian Sea – Ungoza Mountain (“Mangyshlak Mountains”) and site of the Western Chink of Ustyurt between Zhamanairakty and Kyzyltas Mountains (inclusive) on the northeast coast of Kaydak Sor (“Misty Mountains”). In our article, Karelin’s route to the northeastern coast of the Caspian Sea in 1832 and photographs of these localities are given. The type locality of Psammophis lineolatus (Brandt, 1838) should be restricted to the Mangystau Region of the Kazakhstan: Ungoza Mountain south of Sarytash Gulf, Mangystau (Mangyshlak) Penninsula (44°26´ N, 51°12´ E).


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