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1

Spatial distribution and population characteristics of the invasive cladoceran Cercopagis pengoi in the Polish coastal zone seven years after the first record

100%
Bielecka L., Krajewska-Soltys A., Mudrak-Cegiolka S.
Oceanological and Hydrobiological Studies
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2014
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tom 43
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nr 3
2
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Phenology of development and population characteristics of the small spruce bark beetle Ips amitinus (Eichh.) in the Karkonoski National Park

100%
Mazur A., Kuzminski R.
Folia Forestalia Polonica. Series A . Forestry
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2013
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tom 55
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nr 2
In the years 2005– 2006, in the Karkonoski National Park there were conducted observations on infestation of spruce trees by bark beetles (Col., Curculionidae, Scolytinae). Data on bark beetle species composition and frequency of occurrence of individual species were collected. The data on development phenology of the small spruce bark beetle Ips amitinus in the upper subalpine spruce forest sites (1000– 1250 m a.s.l.) indicated higher frequency of occurrence of this species (26.3%) when compared to the European spruce bark beetle Ips typographus. The study included analyses of population size, density, fecundity and mortality of I. amitinus. The rate of development in I. amitinus in the Karkonosze Mts. is similar to that observed in the Alps. The number of laid eggs observed was low and the reproduction success was very high at minimal mortality. Establishment of feeding galleries and egg laying lasted several weeks and 1/3 of feeding galleries were found in the second series of trap trees.
3

Characteristics of the Polish population of horses competing in long-distance rides

100%
Polak G. M.
Annals of Animal Science
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2008
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tom 08
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nr 2
103-111
4

Selected biological characteristics of the catch-available part of population of vendace, Coregonus albula [L.] from Lake Miedwie, Poland

84%
Czerniejewski P., Filipiak J., Poleszczuk G., Wawrzyniak W.
Acta Ichthyologica et Piscatoria
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2004
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tom 34
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nr 2
Background. Due to its economical importance the vendace has been considered one of the most important items of the ichthyofauna of Polish lakes. This is mainly because of favourable biological features of this species, namely: short (2-3 years) period of attaining market size, relatively fast growth rate, schooling behaviour facilitating catches, and most of all the high meat value, making it a desirable consumer item. Materials and Methods. Biological characters were determined in 451 vendace from Lake Miedwie, caught in spring, (124 individuals), summer (132), late summer (87), and autumn (108). The age and growth rates of the fish were determined based on scales using commonly accepted methods. Fulton- and Clark coefficients were used to determine the fish condition. Results. The fish caught were 180-294 mm-long (TL) and weighed 45.2-176.3 g. Mean values of the Fulton coefficient indicated a pronounced improvement in the fish condition from spring to later summer (0.70 and 0.80, respectively) and a slight reduction in autumn (0.75). The age composition of the fish was as follows: 1+, 213 individuals (47.2%); 2+, 229 ind. (50.8%); 3+, 9 ind. (2.0%). The von Bertalanffy equations that describe theoretical growth of the fish examined in length (Lt) and weight (Wt), were calculated. Conclusion. According to the generally accepted criteria of the vendace growth rate, the Lake Miedwie individuals showed a very good growth, higher than that recorded in populations inhabiting other whitefish lakes of Polish Western Pomerania, which indicates the availability of appropriate food resources for the vendace in the Miedwie.
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