Implementation of network Natura 2000 the Protected Landscape Areas of Nature Conservation Agency of the Czech Republic and their monitoring - inventory searches: ichthyology NPR Krumlovsko-rokytenské slepence

There were observed occurence and frequency of selected group of endangered fish species: weatherfish (Misgurnus fossilis), spined loach (Cobitis sp.), European bullhead (Cottus gobio) and Siberian bullhead (Cottus poecilopus)

Method of measuring the protective skin functions against radiation

Aim of this method is make possible quantification of selected characteristics of fish integument, in the concrete quantity of secretion cells in surface layer of epidermis, quantity of epidermal melanophores and ability of mucous layer absorb UV radiation

The ploidy of Carassius auratus in the Czech Republic in light of the artificial reproduction

State of population of Carassius "gibelio" (the sex ratio and ploidy level) was for a long time observed in the Dyje river floodplain, where it has expanded by natural migration from the Danube river through Morava river in 1975-1976. Results show the time dynamics for both parameters, with increasing proportion of males and increasing proportion of diploids of both sex and the formation diploid-polyploid complex. Diploid, triploid and tetraploid males and females of silver crucian carp, Carassius auratus, as well as males of silver Blicca bjoerkna and Rutilus rutilus, were used in mating. The results show different reaction of females on used sperm even in the same group of ploidy. The existence of some groups of the individuals with a different strategy of reproduction in frame single population could be the explanation

Influence temperature and oxygen stress of silver crucian carp (Carassius auratus L.)

The reactions of the individuals of Carassius auratus on temperature and low-oxygen stress were observed. The results show differences in dependence not only on the ploidii levels but also their ancestry. There may be important selective factor in specific natural conditions which affected occurence this groups in specific biotope

Marking of rainbow trout with Alizarin

Method of using alizarin red (ARS) for mass-marking of rainbow trout was verified and optimized. Based on the results, it was possible to create methodological recommendations for marking individuals of rainbow trout using ARS: 1. Marking can be used shortly after hatching (around 14 days) since the fin rays are sufficiently developed or calcified. The standard application time and solution concentration (1 hour, 150 mg/l) can be used if the expected detection time of marker is around 4-5 weeks. It is necessary to increase the application time on 3 hours in order to distinguish individuals 2-3 months after marking. There was no evidence of a negative effect of the dye on rainbow trout individuals (mortality) or a change in chemistry (pH, conductivity, oxygen saturation of water) within standard concentrations and application time and economic parameters. The use of Alizarin red can significantly reduce financial (around 1 CZK/individual) and time requirements for fish marking. When compared with other types of marking, costs can be reduced to 10 percent (or less) and time-consuming (meaning labor costs) can be reduced to several percent. Another advantage that is difficult to quantify is benefit from information obtained by marking on the farms

Implementation of network Natura 2000 the Protected Landscape Areas of Nature Conservation Agency of the Czech Republic and their monitoring - inventory searches: ichthyology NPR Rešovské vodopády

There were observed occurence and frequency of selected group of endangered fish species: weatherfish (Misgurnus fossilis), spined loach (Cobitis sp.), European bullhead (Cottus gobio) and Siberian bullhead (Cottus poecilopus)

Inventory searches within implementation of network Natura 2000 the Protected Landscape Areas of Nature Conservation Agency of the Czech Republicand their monitoring

Monitoring on 5 localities on territory of the Czech Republic was realized in 2013: National Nature Monument Skalická Morávka (PLA Administration Poodří and Ostrava) and National Nature Reserve Křivé jezero, National Nature Reserve Ranšpurk, National Nature Monument Pastvisko and National Nature Reserve Lednické rybníky (PLA Administration Pálava and RO Brno). Observed were occurence and frequency of selected group of endangered fish species: weatherfish (Misgurnus fossilis), spined loach (Cobitis sp.), European bullhead (Cottus gobio) and Siberian bullhead (Cottus poecilopus)

Secundary trout zones and occurrence of grayling (Thymallus thymallus) in the territory of the Czech Republic

In this paper, the relationship between emergence of secondary trout zones below dams, and occurence of the grayling in the waters of the Czech Republic, is studied. The grayling was mentioned as a potentially perspective fish for our waters. This was confirmed by colossal growth of its catches in 1970s and 1980s. The space formed by creation of the secondary trout zones below series of dams, which were built at that time, was very significant for this growth. However, at the turn of the century, a breakpoint was observed, and the numbers of catches decreased to the level of the 1950s. It can be stated that these locaties appear very suitable for this species under specific conditions. However it is necessary to monitor the general dynamics of this biotope, in order to possibly establish an optimal regime fit for present organisms and therefore to form a stable equilibrium