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Genetic variation in North American crayfish species introduced to Europe and the prevalence of the crayfish plague pathogen in their populations
Filipová, Lenka ; Petrusek, Adam (advisor) ; Diéguez-Uribeondo, Javier (referee) ; Trontejl, Peter (referee)
- ABSTRACT (IN ENGLISH) - Biological invasions by crustaceans represent a serious threat for native species in Europe. In my thesis I focus on non-indigenous freshwater crayfish introduced to Europe and their parasite Aphanomyces astaci, the pathogen of the crayfish plague. The thesis consists of four already published first-author papers (chapters I, II, IV and V), two first-author manuscripts (chapters III and VI), and one paper which I co-authored (chapter VII). The first part (chapters I-V) focuses on genetic variation in North American crayfish introduced to Europe. We showed that in two crayfish species, both successful invaders in Europe, genetic variation differs significantly, reflecting their different colonization histories on the continent. The spiny-cheek crayfish Orconectes limosus was likely introduced to Europe just once, in small numbers (90 individuals). Variation at the mitochondrial DNA (mtDNA) level in the spiny-cheek crayfish in Europe is much lower compared to North America (chapter I), although some variation was revealed by nuclear markers in its Central European populations (chapter II). In contrast, the signal crayfish Pacifastacus leniusculus was introduced to Europe several times, in large numbers. Its European populations are highly diverse genetically and belong to a single...
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Genetic variation in North American crayfish species introduced to Europe and the prevalence of the crayfish plague pathogen in their populations
Filipová, Lenka
- ABSTRACT (IN ENGLISH) - Biological invasions by crustaceans represent a serious threat for native species in Europe. In my thesis I focus on non-indigenous freshwater crayfish introduced to Europe and their parasite Aphanomyces astaci, the pathogen of the crayfish plague. The thesis consists of four already published first-author papers (chapters I, II, IV and V), two first-author manuscripts (chapters III and VI), and one paper which I co-authored (chapter VII). The first part (chapters I-V) focuses on genetic variation in North American crayfish introduced to Europe. We showed that in two crayfish species, both successful invaders in Europe, genetic variation differs significantly, reflecting their different colonization histories on the continent. The spiny-cheek crayfish Orconectes limosus was likely introduced to Europe just once, in small numbers (90 individuals). Variation at the mitochondrial DNA (mtDNA) level in the spiny-cheek crayfish in Europe is much lower compared to North America (chapter I), although some variation was revealed by nuclear markers in its Central European populations (chapter II). In contrast, the signal crayfish Pacifastacus leniusculus was introduced to Europe several times, in large numbers. Its European populations are highly diverse genetically and belong to a single...
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Distribution and Ecology of the Stone Crayfish and Noble Crayfish in the Drainage Area of the Zákolanský stream
Kubínyiová, Eva ; Mourek, Jan (advisor) ; Hanel, Lubomír (referee)
This thesis is composed of two parts - research part, focused on field research of occurence and abundance of the Stone Crayfish and the Noble Crayfish in the basin of Zákolanský stream, and a pedagogical part, project Crayfish in the Czech Republic and their protection, aimed for grammar school students. The literature outline summarizes contemporary knowledge about all five species of crayfish in the Czech Republic. Our native species are the Stone Crayfish (Austropotamobius torrentium) and Noble Crayfish (Astacus astacus). The non-native are Narrow-clawed Crayfish (Astacus leptodactylus), Spiny-cheek Crayfish (Orconectes limosus) and Signal Crayfish (Pacifastacus leniusculus). Aside from the chapters concerning the particular species and their determination, the literature outline also contains general information about the life and endangerment of crayfish. I have conducted the field research from April to September 2009. I also noted and evaluated the environmental conditions of the crayfish habitats. Based on the adjusted AOPK ČR methodology, I selected eight 100-meter long brook-sections of the Europe-important locality of Zákolanský stream, with the previously confirmed occurrence of crayfish. From the eight sections, I found crayfish only in three. All the captured specimens were of the...
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Distribution and genetic variation of invasive crayfish of the genus Orconectes
Filipová, Lenka ; Petrusek, Adam (advisor) ; Kozák, Pavel (referee)
Crayfish are an important part of European fauna, but since the 19th century native crayfish species have been largely influenced by biological invasions, when large number of their populations was dramatically reduced due to the introduction of the pathogen of the crayfish plague (oomycete Aphanomyces astaci) to Europe. Several North American crayfish species were then brought to the European continent to substitute lost populations of native crayfish, the most widespread being the spiny-cheek crayfish (Orconectes limosus), the signal crayfish (Pacifastacus leniusculus) and the red swamp crayfish (Procambarus clarkii). However, these crayfish can carry pathogen of the crayfish plague and therefore represent a serious threat to the native species. My work focused mostly on the spiny-cheek crayfish (O. limosus). Available literature data suggest that the species was brought to Europe only once, and all European individuals may be descendants of the founder population. However, other cases of introduction may not have been documented, and cannot be ruled out. The first aim of my thesis was to evaluate the haplotype variation of the spiny-cheek crayfish populations from Europe and North America. Mitochondrial gene for cytochrome c oxidase subunit 1 (COI) of selected O. limosus individuals from several...
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Occurrence of PBDE compounds and Bisphenol A in rivers with the occurrence of cryfish
Svobodová, Kateřina ; Vach, Marek (advisor)
The thesis deals with result evaluation of a project under the auspices of the EAA and Norway Grants, which ran from 2015 to 2016. The project's goal was to evaluate water quality at sites with native and invasive crayfish. The project also included monitoring organic substances such as Polybrominated diphenyl ethers (PBDEs). I mainly focused on a subset of PBDEs, the brominated flame retardants (BFRs). These substances have been monitored since the 1970s, when food was accidentally contaminated leading to the contamination of the nearby area in the US. What is alarming is their persistence in the environment, which leads to their constantly increasing levels. Information about the transformation and biodegradation of PBDEs in the environment is still limited and is continually analyzed in new studies. These substances are poorly volatile and insoluble, which makes dust and particles arising from the products containing BPAs the main sources of contact. Another agent, whose presence in the environment of the Czech Republic I analyzed, is Bisphenol A (BPA). BPA is used in the production of epoxy resins and polycarbonate plastics. BPA is a toxic substance with the ability to disrupt hormone function. Baby feeding bottles have been confirmed to contain these compounds. In April 2004, the Czech government approved a (program to reduce pollution of surface waters by dangerous harmful substances). In August 2004, the EU enacted a ban on the sale and use of penta-BDE and octa-BDE in all fields. Since 2011, Bisphenol A may not be used in the manufacture of baby feeding bottles. The goal of this thesis is to analyze and evaluate the amount and possible consequences of these substances in our environment, which are alarming even after full or partial bans on the use of these substances.
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The issue of crayfish repatriation - A literature search and examples from practice
HRBEK, Vladimír
The issue of crayfish repatriation - A literature search and examples from practice The numbers of crayfish in our water bodies decreased in last few decades. Mainly because of crayfish plague which is carried by American crafish species. That is why it is important to do repatriation processes. For the repatriation or any manipulation with crayfish is needed an exception based in law. This exceptions are provided since 2009 by regional offices or by the management of protected landscape areas. Before 2009 this competence belonged to the Ministry of Environment. The authorities claim they have issued only six exceptions concerning reapatriation. unfortunately the reality is different. Particularly the Ministry of Environment provided information that they did not find any records of exception concerning repatriation. The truth is that they did so even several times.
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The effect of metribuzine on oxidative stress and antioxidant enzymes of signal crayfish
LIDOVÁ, Jaroslava
The aim of this study was to investigate effects of the triazine herbicide metribuzine on oxidative stress level and antioxidant enzymes activity in gills, muscle and hepatopancreas of signal crayfish (Pacifastacus leniusculus Dana) and also extension of knowledge about effect of metribuzine on the environment. The experiment took up 60 days. Crayfish were exposured to metribuzine concentrations of 0.52 micrograms.l-1 (real environmental concentration) and 3.06 mg.l-1 (10% 96hLC50) for the first 30 days. Then a second phase followed depuration without metribuzine (30 days). Changes in the oxidative stress level (TBARS), superoxiddismutase (SOD) activity and catalase (CAT) activity were observed in all examined tissues. Changes in glutathionreductase (GR) activity were observed only in hepatopancreas. Chronic exposure of metribuzine demonstrated an oxidative damage of cell lipids, proteins and also changes in antioxidant activity in examined crayfish tissues.The results of this study suggest that crayfish are a very suitable organisms for toxicological tests and simultaneously extend knowledge about effect of metribuzine on the environment.
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Vliv triazinových pesticidů na ryby
STARÁ, Alžběta
Fish and crayfish are widely used as biological monitors of environmental levels of anthropogenic pollutants. The present thesis is a contribution to the assessment of the toxicity and effects of long-term effect of triazines on the different developmental stages of common carp (Cyprinus carpio L.) and adult red swamp crayfish (Procambarus clarkii). The carp was selected as a model fish due to its economic importance, e.g. carp farming contributes about 90% to total fish production in the Czech Republic. Crayfish are easily identified species representing given locality, they are widespread, and they provide a sufficient amount of tissue for individual biochemical and chemical analyses. The results of these studies provide further data on chronic exposure to triazines for consideration in risk assessment. We selected three active substances of triazine herbicides which are the most frequently detected in surface waters such as prometryne, simazine and terbutryn. The findings contribute to knowledge of the toxic potential of triazine herbicides to carp and crayfish at environmentally relevant concentrations in Czech rivers. There is a scarcity of information regarding the toxicity of triazines on freshwater organisms. During the tests we monitored several parameters: behaviour, mortality, biometric, haematological, biochemical blood, histopathology, oxidative stress and antioxidants. The data obtained from all tests performed during my thesis are very valuable for assessment and evaluation of long-term effects xenobiotics on aquatic organisms, especially fish and crayfish. In the future, I would extend the focus of my research for study of possible synergic or amplifying effect of mixtures triazines with other xenobiotics which are often found in the aquatic environment. This approach is recently accented as the aquatic environment is polluted by mixtures of different compounds. Therefore, more research is needed in order to clarify the more detailed effects of xenobiotics on non-target aquatic organisms.
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Cray fish as bioindicators of human impact in freshwater ecosystems in CR - sensitivity of model species on selected toxic compounds and case study from the model catchment
MAHOVSKÁ, Ivana
This thesis deals with monitoring the occurrence of crayfish in selected river basins in the western Bohemia, considering the human impact on freshwater ecosystems and his influence on crayfish and other aquatic organisms. The selected river basin territory was Úhlava, Úslava and Otava. In the localities, numerical and species-wise representation of crayfish was monitored by finding data from the Agency for Nature Conservation and Landscape of Czech Republic database. The flow and environment characteristics were also monitored. This thesis focuses on water quality in streams of selected major river basins, Úhlava, Úslava and Otava rivers in the period from 2006 to 2011. Results of the findings show a sympatric occurrence of original species, stone crayfish (Austropotamobius torrentium), noble crayfish (Astacus astacus) and part of the original danube crayfish (Astacus leptodactylus) with invasively spreading species of spiny-cheek crayfish (Orconectes limosus) and signal crayfish (Pacifastacus leniusculus). With respect to this fact, the sensitivity of spiny-cheek crayfish (Orconectes limosus) and signal crayfish (Pacifastacus leniusculus) are evaluated in a form of own test results on acute toxicity. The thesis compared current results of occurrence and the protection of crayfish in the Czech Republic and abroad. The conclusion of this thesis is a proposal of a freshwater biomonitoring system, using the crayfish.
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Impact of american mink on stone crayfish populations
PAVLUVČÍK, Petr
1. Impact of introduced American mink (Mustela vison) predation on endangered stone crayfish (Austropotamobius torrentium) was examined in western Bohemian middle-sized streams for two years. Mink diet selectivity and its impact on its prey abundance were been investigating as the main target of this study. 2. The mink diet was described from excrements which were found on the target areas. The importance of different types of prey was specified by their relative numeric contribution to diet. The number of hunted crayfish was elicited from the number of crayfish remains which were collected during two years. The crayfish abundance was determined by capture {--} recapture method. 3. The crayfish was most frequently observed component of mink diet. The rate of mink predation on crayfish was dependent on density of crayfish population. This observed rate was lower during winters than during summers. The mink preferred significantly longer crayfish than was the mean of this value in population. 4. Although the crayfish was important part of mink diet the trend of impact of mink on crayfish is still inexplicit. It would be important to continue in this research to determine correlation between these two species.
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