Blue Bream Research Articles

Ecology of proteocephalus torulosus in the blue bream (Abramis ballerus) fromthe oder river on the borders of germany and poland

During studies on the ecology of fish helminths, the tapeworm Proteocephalus torulosus (Batsch, 1786) was frequently found in the intestine of the blue bream (Abramis ballerus) from the Oder River (Germany/Poland). In total, 633 fish, ranging between two and 16 years old, were sampled at monthly intervals over a two year period during 1993-1995. Statistically significant differences in the seasonal occurrence of the parasite in its fish host were observed. In 1993, the prevalence remained at a high level, ranging between 61. 9 and 100%. During the summer of 1994, this value decreased to 5.5% and remained low for the rest of the year. The pattern of mean intensity of infection was similar to that of the prevalence. In 1993, the mean intensity varied between 8.4 and 31.8 worms per infected fish, with a continual loss of worms being observed in the summer of 1994. Changes in the amount of suspended particulate matter in water have been identified as the main cause of these observed differences in the course of infection of blue bream.

Ciliates (Ciliophora) parasitic on the gills of the blue bream, Abramis ballerus (L.) from Dąbie Lake (Poland)

Ciliates (Ciliophora) parasitic on the gills of the blue bream, Abramis ballerus (L.) from Dąbie Lake (Poland)

Reproduction and fecundity of blue bream Abramis ballerus L., 1758 in Międzyodrze

The age and length distribution of the blue bream spawning population of Międzyodrze-the wetland area in the lower part of the river Odra-was examined in the years 1992-1996. The length and age of sexual maturity was determined, the relative gonads size of mature fish in autumn and spring seasons as well as relationship between fecundity and weight or length of females was assessed.

Biometric characters of the blue bream Abramis ballerus (L.) (Cyprinidae) from Lake Dąbie

The paper presents results of study on 24 metric characters and 19 meristic ones, performed on 50 specimens of the blue bream collected in Lake D±bie. With the aid of Cochran and Cox test the results obtained were compared with the data concerning the population from the river Dnepr.

Environmental factors as forces structuring the fish community of the Elbe Estuary

Smelt, flounder, eel, three‐spined stickleback, twaite shad, ruffe and herring were the major species among 62 forming the fish community of the Elbe estuary. Species richness, species diversity, evenness and total fish biomass decreased in the upstream direction. Total abundance was greatest during summer. Salinity was the most significant physico‐chemical factor affecting species richness and total fish biomass, whereas water temperature was the best predictor of total abundance. Marine fish species decreased with decreasing salinity, while the freshwater species roach and ide were absent at salinities > 15‰. Bream, blue bream, white bream, perch and pikeperch occurred more frequently in shallow marginal regions with lower current velocities, while herring and other marine species occurred closer to the deep central regions with high current velocities. Annual and seasonal variations of the community structure mainly reflected in population dynamics of smelt, flounder, twaite shad, three‐spined stickleback and eel, especially those of 0‐age smelt. Populations of smelt and ruffe and their importance in the fish community increased between 1989 and 1992, while those of twaite shad and eel decreased. At oxygen concentrations <3 mg I1, smelt and flounder were rare, but eels were at their maximum at 3.5 mg I−1. Changes of species composition and fish abundance were closely related to daytime and tidal cycle.

On biology of reproduction of blue bream, Abramis ballerus (L., 1758), in the lower part of river Odra, Lake Dąbie and Szczecin Lagoon

The present paper demonstrates results of examinations on seasonal course of gonads ripening, localisation of spawning places, spawning process, sex ratio in the spawning stock eggs diameter, as well as investigation on fecundity of blue bream. The spawning places being found out were situated in shallow, sheltered waters of canals of “Międzyodrze”.

Catches and growth rate of Abramis ballerus (L., 1758) from Lake Dąbie and the Firth of Szczecin

Catches and growth rate of Abramis ballerus (L., 1758) from Lake Dąbie and the Firth of Szczecin

Prey Detection in Cyprinids during Early Development

Larval and juvenile fish of roach (Rutilus rutilus L), bleak (Alburnus alburnus L), and blue bream (Abramis ballerus L.) were investigated weekly to define the ontogenetic development of prey detection capacities. Visual acuity was determined by measuring reactive distances for zooplankton prey for fish from 8 to 50 mm standard length using video recordings. Data of reactive distances, swimming speeds, and the characteristics of the visual field were combined to calculate prey location volumes. Prey location capacity increased exponentially with fish size which implies enormous differences in prey encounter rates among size classes of cyprinids. Distinct differences of prey location capacities occurred between species in the juvenile, planktivorous stages of the three cyprinids coinciding with the trophic differentiation of the adults.

Comparative morphology and ecomorphology of the gut in European cyprinids (Telostei)

The patterns of coiling of the gut were compared in 22 species of Eurasian Cyprinidae. In selected species, also the length of gut and mucosal surface structure were compared. Piscivorous (Aspius aspius), planktivorous (Abramis ballerus) fishes as well as species feeding mainly on plankton and wind‐borne‘ drift’(Alburnus alhurnus, Pelecus cultratus) have the relatively shortest guts, with only a single loop. The same simple arrangement of a short gut is present in many euryphagous species with more or less carnivorous tendencies (Abramis sapa, Alburnoides bipunctalus, Abramis brama, Blicca bjoerkna, Chalcalburnus chalcoides memo, Gobio gobio, Leuciscus cephalus, Leuciscus leuciscus, Rutilus rutilus, Scardinius erythrophthalmus. Tinea tinea, Vimba vimba). Some benthivorous winnowers (oropharyngeal sorters) and species with herbivorous feeding tendencies have relatively long guts showing a more complex pattern of loops and coils (Barbus barbus, Carassius carassius, Chondrostoma nasus, Ctenopharyngodon idella, Cyprinus carpio). The goldfish, Carassius auratus, has the most complex coils. Scanning electron microscopy of the mucosal surface revealed five types of folding in the intestinal bulb which were only loosely related to feeding: 1, smooth surface (Aspius aspius, Leuciscus cephalus, Vimba vimba); 2, irregularly branching folds (Alhurnus alburnus, Barbus barbus, Blicca bjoerkna, Chalcalburnus chalcoides memo, Leuciscus leuciscus, Rutilus rutilus, Scardinius erythrophthalmus); 3, curl‐like folds (Tinea tinea); 4, net‐like folding pattern (Abramis brama); 5, honeycomb‐like mucosal structure (Cyprinus carpio).

Trichodinid Protozoa (Ciliophora: Peritrichida) from Freshwater Fishes of Rybinsk Reservoir, USSR1

ABSTRACTDuring the spring of 1981, trichodinid protozoa were collected from the gills or urinary bladder of the following species of fishes of Rybinsk Reservoir, USSR, located on the upper reaches of the Volga River system: Esox lucius, Rutilus rutilus, Leuciscus idus, Blicca bjoerkna, Abramis ballerus, Pelecus cultratus, Lota lota, and Perca fluviatilis. A total of 13 species of Trichodinidae was recovered from Rybinsk fishes, among which are three new species of the genus Trichodina: T. izyumovae n. sp. from the gills of L. idus, T. borokensis n. sp. from the gills of P. cultratus, and T. kupermani n. sp. from the gills of A. ballerus. Other species of trichodinids reported are T. modesta Lom, 1980; T. nigra Lom, 1969; T. pediculus (O. F. Müller, 1786); T. prowazeki Grupcheva & Lom, 1980; T. rostrata Kulemina, 1968; T. urinaria Dogiel, 1940; T. ophiocephalus Kostenko & Karaev, 1976; Paratrichodina incisa (Lom, 1959); Trichodinella epizootica (Raabe, 1950); and Tripartiella copiosa Lom, 1959. Photomicrographs and morphometric data are presented for each species and aspects of their host and geographic distribution discussed. Trichodina algonquinensis Li & Desser, 1983 is considered a synonym of T. urinaria Dogiel, 1940.

Accumulation of mutagenic activity in bile fluid of river Rhine fish

Thyroid hormones (THs) are involved in regulation of many life history traits of fishes. Development, growth, reproduction and shaping the adult phenotypes were found to be regulated by THs. Regulatory evolution is one of the main factors driving morpho-ecological diversification and speciation. We tested a hypothesis whether closely related but ecologically diverged species may have a diverse level of THs. We compared seasonal levels of plasma concentrations of triiodothyronine (T3) in two cyprinid species, benthophagous bream Abramis brama and zooplanktivorous blue bream Ballerus ballerus. Significant differences in T3 concentrations were detected. B. ballerus had substantially reduced T3 levels as compared to most other species of fish. Two hypotheses explaining the thyroid divergence are discussed. Despite differences in absolute T3 concentrations, both species manifest similar seasonal cycling with increased plasma T3 levels in warmer seasons and decreased T3 in colder seasons. Several peaks of plasma T3 level were registered: at pre-spawning periods, at mid-summer and in the early autumn. The pre-spawning peak noted in cyprinids was a novel observation. Significant positive correlations were detected between water temperature and plasma T3 concentrations, as well as between the duration of daylight and T3 plasma concentrations in both species.

Contribution to the study of drinking water, danube water and biocenose contamination with chlorinated insecticides

The present paper deals with the methods of determination of BHC isomers, of DDE, DDT and HCB in waters, drinking and surface waters from the Danube; in two sorts of fish living in the Danube: herbivorous ( Cyprinus carpio L., Abramis ballerus L., and Chondrostoma nasus L.) and carnivorous ( Esox lucius L., Lepomis gibbosus L., Aspius asptus L. and Perca fluviatilis L.); in sediment and water plants using GLC and TLC. In the period 1971–1974, the mean concentrations of the compounds studied were: in drinking water from 0.00 to 0.12 μg/1; in the waters from the Danube from 0.006 to 0.197 μg/1; in predominantly herbivorous fish from 0.00 to 2.58 mg/kg; in sediment from 0.01 to 2.11 mg/kg; and in water plants from 0.002 to 0.032 mg/kg. The mean levels of the studied compounds found in the fish were 1000–10,000 times higher than those of the water. Comparing the average contents of the BHC isomers as well as of DDT and DDE in fish, considerably higher concentrations of DDT and DDE were found as compared with the BHC levels, mainly in carnivorous fish. Differences in the contents of the insecticides studied are due to their different cumulative properties.

Investigations on the Subfossil Fresh-Water Fishes in the Soviet Union

INVESTIGATIONS of the fish remains connected with the dwelling places of prehistoric man began as early as the last quarter of the 19th century. The first to study the fish bones obtained in the stations of prehistoric man of our country was K. T. Kessler. In 1882 he published his work on fishes found near Ladoga Lake. Since then material has accumulated which allows us to outline some stages in the history of the eastern European ichthyofauna. Fish remains connected with palaeolithic man are very scarce. Thus far it has been possible to investigate only the discoveries made in Crimean caves (Tichij, 1929) and in stations near the town of Novgorod-Seversky on the banks of the Desna River, a tributary of the Dnieper (Nikolsky, in litt., Lebedev, 1944). Examination of these two collections shows that during the last interglacial epoch the members of the genus Salmo were more common in the Black Sea basin than they are today. Furthermore, the occurrence of the ling, Lota iota, in the collection indicates that the climate of the period studied was more rigorous than that of today. The discovery in the Crimean caves of large specimens of Rutilus frisii and Lucioperca lucioperca shows that in this interglacial epoch the mouth of some large stream, apparently the Palaeo Dnieper, had been situated more to the east than that of the modern Dnieper, i.e., not far from the place where the fish remains were found. At present those large fishes are very rare off the Crimean coast of the Black Sea. In postglacial deposits, fish remains are more abundant, and they are useful for establishing essential differences between the ichthyofaunae of sub-boreal and modern times. For example, from materials found in neolithic stations in the Baltic Sea basin, a higher proportion of thermophilic fishes was obtained than occurs in that area now. Also, K. T. Kessler (1882) has shown that in the sub-boreal period, in Lake Ladoga basin, there had been a considerably greater abundance of Silurus glanis, of Lucioperca lucioperca, and of Lucioperca volgensis. The latter species now occurs solely in the Black and Caspian sea basins and is absent from the Baltic. Still greater changes are observed to have taken place in the ichthyofauna of the White Sea basin (Nikolsky, 1935, 1936, 1943). Fish remains found in stations of the Onega River basin show that the ichthyofauna of the sub-boreal period included many species of fishes-40 per cent of the material-which were of southern origin, which now inhabit the Aral Ponto Caspian province and the Baltic region, and which have disappeared from the White Sea basin. The following species which occurred in the earlier period are no longer found in the White Sea basin: Aspius aspius, Scardinius erythrophthalmus, Abramis ballerus, Silurus glanis. Not only the specific composition but also the abundance of the fishes were different than they are today. In the Onega River basin it was the bream and other