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Genetická diverzita ohrožených druhů ryb – nezbytný základ efektivní ochrany biodiverzity
Ústav živočišné fysiologie a genetiky AV ČR, v.v.i., Liběchov ; Ústav biologie obratlovců AV ČR, v.v.i., Brno ; Lusk, Stanislav
Hlavním cílem projektu je identifikace vnitrodruhové genetické diverzity ohrožených druhů mihulí a ryb v ČR (2 druhy mihulí a 20 druhů ryb). Výsledky získané v rámci řešení projektu jednoznačně prokázaly, že dosud nerespektovaná „vnitrodruhová“ nebo "genetická" diverzita je nesmírně cenný fenomén, který má vysokou hodnotu a je nezbytné realizovat opatření, které zásadním způsobem sníží rizika jeho narušení a devastace, v krajním případě zamezí jeho zániku. Získané výsledky nastolují i některé problémy. Jednak je to problém ochrany vnitrodruhové diverzity u druhů, které nejsou posuzovány jako ohrožené, a které nejsou z hlediska legislativního předmětem ochrany. Jako příklad lze uvést situaci u hrouzka obecného. S tím souvisí další problém, tj. kdy poznatky o genetické diverzitě vedou k tomu, že místo jednoho druhu, který je předmětem ochrany, determinujeme několik druhů, jak je tomu např. u hrouzka běloploutvého. Popis výsledků řešení a prezentační výstupy výsledků řešení projektu.
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The latest findings concerning the species diversity of gudgeon of the genera Gobio and Romanogobio in the territory of the Czech Republic and Slovakia
Mendel, Jan ; Lusk, Stanislav ; Lusková, Věra ; Koščo, J. ; Vetešník, Lukáš ; Halačka, Karel
During last 15 years the taxonomy of gudgeon have undergone extensive changes. The findings important for preservation of ichthyofauna of the Czech Republic and Slovakia include confirmation of generic differentiation of the original genus Gobio into two genera Gobio and Romanogobio. On the basis of genetic analyses, the originally accepted uniform structure of the species Gobio gobio was divided into the structures which can be assigned the level of species (G. gobio, G. obtusirostris, G. carpathicus, Gobio sp.). The original R. albipinnatus can be divided into the species R. vladykovi and R. belingi. The original species R. kesslerii can be divided into R. banaticus and apparently also Romanogobio sp. With regard to newly acquired knowledge it is necessary to revise the system of efficient preservation of the biodiversity found in the above mentioned taxa. The areas of sympatric occurrence of some species were localized and hybridization within both the genera was demonstrated.
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Molecular biological analyses of Sand gudgeon (Romanogobio kesslerii) in the waters of the Czech Republic and Slovakia
Mendel, Jan ; Lusk, Stanislav ; Lusková, Věra ; Koščo, J. ; Papoušek, Ivo ; Halačka, Karel ; Vetešník, Lukáš
Kessler's gudgeon belongs to critically endangered species protected by both national and European legislation. We present the first findings concerning the genetic diversity of 5 R. kesslerii populations from the Czech and Slovak rivers. On the basis of sequencing of the control region, as well as of the first intron of the S7 r-protein, 30 specimens were analysed. Altogether nine haplotypes were identified. Analyses of mtDNA showed the existence of two groups differing by 6.2%. The first group included the specimens from the rivers Bečva and Ipel and the second group included the specimens from the rivers Topl’á, Laborec and Morava. The inter-population diversity was 0.4% within the first group and it ranged from 0.5% to 1.0% within the second group. The combination of the methods of sequencing of parts of mtDNA and nDNA and allozyme analysis revealed the presence of hybrids of G. gobio and R. kesslerii in the Morava and Ipel’ rivers.
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On the occurrence of rare and protected lamprey and fish species in the Morava River drainage area
Lusk, Stanislav ; Lusková, Věra ; Lojkásek, B. ; Halačka, Karel ; Vetešník, Lukáš ; Merta, L.
The occurrence of a considerable number of rare and protected lamprey and fish species in the Czech Republic is exclusive for the drainage area of the Morava River. Eudontomyzon mariae occurs only in the Račí potok Brook. Lampetra planeri occurs in a section ca 20 km long in the upper part of the Morava R. Romanogobio kessleri initially occurred only in the Bečva R. After 2000 was newly recorded in the Morava R. Romanogobio albipinnatus occurs in the lower reaches of the rivers Morava and Dyje; locally, we have observed in the upper parts of these rivers. After 1990 species Pelecus cultratus, Gymnocephalus schraetser, G. baloni, Zingel streber, and Z. zingel re-occurred in the confluence of Morava and Dyje rivers. The only actual range of Sabanejewia balcanica in the Czech Republic is in a short section of the Vlára R. (the Váh R. drainage area) near the boundary of Slovakia. Cobitis elongatoides occurs, in its pure form, only in the upper part of the Dyje R. drainage area.
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Alien fish species in the Odra basin on Moravien and Silesian
Lojkásek, B. ; Lusk, Stanislav ; Papoušek, Ivo
In the territory of Moravian and Silesian, the upper part of basin of the River Odra is found, where the riverine net is formed by smaller streams. The original ichthyofauna species structure is therefore, relative poor, representing 2 lamprey and 33 fish species, from which at present, 1 lamprey and 3 fish species are considered to be extinct. During the 19th and 20th centuries within human activities, 8 alien exotic species were introduced and 5 non-native species for this area were dislocated. All introduced and dislocated species are subject to fishery management. Regards to the fact that the species Carassius carassius and Pseudorasbora parva reproduce naturally, their relationships and influence are negative to the native species, they are assessed as invasive alien species.
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Changes in abundance of bullhead (Cottus gobio L.) in the Loučka stream near Skryje in 1968-2004
Humpl, Martin ; Lusk, Stanislav
In the site of the Loučka R., the long-term (1968-2005) monitoring has been realized, always during the autumn period. A part of the Loučka R. was selected and included in the national list of the „European important localities“ for the bullhead Cottus gobio. In the monitored section of the Loučka R., the fish community of salmonid type occurred with dominance of the species brown trout Salmo trutta m. fario, grayling Thymallus thymallus, Cottus gobio and stone loach Barbatula barbatula. The estimated abundance of the bullhead ranged from 128 to 1778 ind.ha-1, means of 504 ind.ha-1. The abundance fluctuations occurred in 10-years’ cycles. The proportion of the bullhead in the total fish abundance ranged from 4% up to 30%. The positive correlation was found between the bullhead abundance and that of grayling and stone loach. The results obtained signalise the need of care in assessing the bullhead population status in the case of less numerous and unsystematic data on abundance.
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The first record of the black bullhead (Ameiurus melas) in the Třeboň district, Czech Republic
Hartvich, P. ; Lusk, Stanislav
In the Czech Republic, the occurrence of the Black bullhead, Ameiurus melas (Rafinesque, 1820) was recorded for the first time. The species occurs in some of the fishponds in the environs of Lomnice nad Lužnicí, southern Bohemia. The species was introduced unintentionally as an admixture to carp stocking material from Croatia in 2003. In the autumn of 2005, the occurrence was observed of adults as well as yearling fry, indicating that natural reproduction had taken place in some of the ponds. The water from the fishpond system is released into the Lužnice River so that there is a possibility of the species spreading over natural habitats of the river mentioned. The occurrence of this species in the fishponds in southern Bohemia tends to confirm the fact that transports of stocking fish, above all, carp but other species as well, present a real risk of unintentional introductions of non-native species and an important way of their subsequent dispersal.
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Long-term monitoring of the populations of Eudontomyzon mariae in the Račí potok brook (1998-2006)
Hanel, L. ; Lusk, Stanislav
The occurrence of the Ukrainian lamprey (Eudontomyzon mariae) in the Račí potok Brook is the only known population of this lamprey in the Czech republic. The status of the locality and population numbers of this species was followed up in 1998 through 2006. It is evident that the population size (as shown by the results of electro-fishings using invariably the same technique) is slightly increasing. Compared to 16 larvae.ha-1 in 1998, their number increased to 327 larvae.ha-1 in 2006. The abundance data were converted to the bottom surface, not only to that of suitable fine sediment deposits. In 2006, the same stream section was experimentally fished twice, and it has appeared that additional larvae were present in the second run (the increase in abundance being ca 38 %). In our opinion, the gradual increase in the population size of the Ukrainian lamprey in the Račí potok Brook is due to the recent revitalisation modifications of the brook bed.
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