Unionoid mussels are globally threatened and their conservation requires species-specific knowledge on their ecology and parasite-host interaction. Unio crassus is one of Europe’s most threatened unionoid species and has a temporary obligate parasitic life stage (glochidia) on fish. A lack of suitable hosts is probably a major limitation for mussel recruitment, but host species composition, suitability and availability in time and space have yet to be fully explored. This thesis examines different aspects of the host fish species, including their composition, suitability and ecological importance, in relation to U. crassus, using both field and laboratory studies. The effects of mussel and host density on mussel reproductive potential were considered, as were aspects of evolutionary adaptations between mussels and fish and how climate change may affect their interaction. The results show that U. crassus is a host generalist, parasitizing a variety of fish species. Host suitability and density, which varied among fish species and rivers, affected the level of glochidia encapsulation, hence mussel reproductive potential, more so than the density of mussels taking part in reproduction. Ecologically important hosts included both highly suitable primary hosts, and less suitable hosts that were highly abundant. Whether or not U. crassus has specific adaptations to its hosts to enhance juvenile transformation remains unclear. No distinct pattern of local adaptation was found, nor was there an effect of host fish presence on the timing of glochidia release by adult mussels. Instead, temperature played a major role, with results suggesting that changes in spring water temperature regimes can cause temporal and spatial mismatches in the mussel-host interaction. This thesis indicates that investigations of local mussel-host interactions help in identifying mechanisms important for unionoid conservation management and prioritization. / Många sötvattenmusslor har en komplex livscykel där larverna (glochidier) under sin utveckling till frilevande musslor parasiterar på gälarna hos lämpliga värdfiskar. Flera av våra musslor, såsom den tjockskaliga målarmusslan (Unio crassus), är globalt hotade och för att kunna bevara och förvalta dessa arter på bästa sätt behöver vi lära oss mer om deras ekologi och samspelet mellan musslan och dess värdfiskar. Avsaknaden av värdfiskar innebär förmodligen en stor begränsning för rekryteringen av juvenila musslor, men det finns trots detta en begränsad kunskap om hur artsammansättningen i fisksamhället och dess tillgänglighet påverkar musselpopulationer.  Min avhandling undersöker olika aspekter av interaktioner mellan U. crassus och dess värdfiskar, som hur värdfisksamhällen och fiskarters värdlämplighet påverkar musslans reproduktionspotential. Jag har även studerat hur tätheter av olika fiskarter och vuxna musslor påverkar rekryteringen, eventuella evolutionära anpassningar samt om en förhöjd temperatur skulle kunna påverka interaktionen mellan U. crassus och dess värdfiskar. Resultaten visar att U. crassus är en generalist som parasiterar på en mängd olika fiskarter. Jag fann dock en stor variation i dominerande fiskarter och lämpliga värdar mellan olika åar, vilket påverkade reproduktionspotentialen hos musslorna mer än vad tätheten vuxna musslor som deltog i reproduktionen gjorde. Som ekologiskt viktiga värdar fanns således både särskilt lämpliga, primära värdarter, men också mindre lämpliga arter som förekom i höga tätheter. Ingen tydlig lokal anpassning kunde observeras, och fiskens närvaro påverkade inte tidpunkten för när de vuxna musslorna släppte sina glochidielarver. Däremot fann jag att temperaturen spelade en viktig roll för musslans reproduktion, där ökad temperatur föreslås ha negativa effekter på interaktionen mellan musslan och dess värdfiskar. Avhandlingen visar på vikten av att studera interaktioner mellan den tjockskaliga målarmusslan och dess värdar på lokal skala för att bättre kunna identifiera och prioritera viktiga naturvårdsåtgärder. / UnioCrassusforLIFE (European LIFE+ project: LIFE10 NAT/SE/000046)

Enneacanthus chaetodon, the blackbanded sunfish, has become increasingly rare throughout its distribution in the Eastern United States. In Virginia, E. chaetodon maintains an endangered status and individuals persist in six populations. Mitochondrial DNA (mtDNA) and microsatellite data were assessed to determine the genetic characters and gene diversity of the Virginia populations. The results of these analyses were then compared to five additional populations; four from New Jersey and one from North Carolina that were known to have relatively good fitness and were not impacted severely by habitat alteration. The results of this study are relevant to selection of proper management techniques and strategies for this species. Mitochondrial DNA analyses detected no variation in the Virginia populations but significant (P F > 0.2) of inbreeding. The New Jersey and North Carolina populations demonstrated lower amounts of inbreeding than populations in Virginia. New Jersey displayed a significant (P < 0.05) amount of subdivision among populations compared to Virginia. Hypothesis testing supported the contention that the regions are significantly different from one another and that Virginia populations may have gone through one or more population bottlenecks in the past, explaining the low levels of diversity observed and significantly high inbreeding coefficients. Captive breeding programs could be implemented as a management measure to increase population numbers and restore fish into areas where they have been known to inhabit in the recent past. From a proper management perspective, habitat protection and maintenance are more important than supplementation to population survival. Success of either approach with Virginia populations would provide a useful model for managing small populations of blackbanded sunfish in other regions.This project was supported by a grant from the Virginia Department of Game and Inland Fisheries (VDGIF), grant #ED0817BB.

The name and the central topic of this thesis is "Criminal Liability in Environmental Protection" and it is divided into two main parts. Firstly, it is an analysis and a description of a valid legal regulatory framework of criminal liability in environmental matters within the Czech legal system with a full description of each of the offences against environment under the new Criminal Code, Act N. 40/2009 Coll., as amended. The focus of the second part is on the international illegal trade in wildlife and the problems of enforcement. First chapter of this part is dedicated to the Convention on International Trade in Endangered Species of Wild Fauna and Flora. In the second chapter I focus primarily on the problems of enforcement, which remain even though wildlife crime (and environmental crime in general) seems to benefit from an increasing profile amongst agencies tasked with its control. The last chapter of this part aims to explain the term "Situational Crime Prevention".

This thesis deals with geographical distribution and taxonomy of Steccherinum genus in the Czech Republic. Members of this genus are corticioid fungi of Meruliaceae family, characterized by odontioid hymenophore, small spores and encrusted pseudocystidia. Presence of nine species was confirmed in Czech Republic on the basis of herbarium specimen revision and study of my own collections. Analysis of ITS and LSU nrDNA gene regions was used to create phylogenetic trees. These trees show relations in Steccherinum genus and related species. Selected traits in specimens of S. ochraceum s. l. (number of spines, their length, spore size and pseudocystidia size) were measured. This was followed by investigation of morphological variability in individual specimens and in relationship to ecological conditions (substrate and elevation). Morphology of selected individuals was compared with molecular data afterwards. Two clades were defined in S. ochraceum s. l. - existing differences between them are presumably caused by intraspecific genetic variability. S. rhois could not be separated as individual species on the basis of phylogenetic analysis. Dependence of fruiting body morphology on ecological conditions wasn't supported by results. Maps of geographic distribution of individual species of Steccherinum genus are...

The purpose of the thesis is to describe international, EU and Czech wildlife trade laws by identifying the regulatory measures established at these levels of law and examining them from the perspective of each. It further seeks to analyze how CITES obligations governing these measures are incorporated into the EU and Czech legislation and investigate whether they are likely implemented inadequately or, conversely, more strictly. Additionally, it points out some of the potential problems of the current legal framework as well. The thesis is composed of six chapters. Chapter one explains the goals of environmental policy in the area of nature conservation and biodiversity protection related to wildlife trade and reasons for the very existence of its regulation. Chapter two is concerned with general aspects of wildlife trade law such as its objective, purpose, principles and role within environmental law. Chapter three outlines the main and also some other relevant sources of law. Chapter four determines the principal regulatory measures which are contained within the legal regime in order to enable it to achieve its objectives. The fifth chapter then focuses on two groups of legal means designed to ensure the compliance of CITES parties and to enforce the provisions of EU and Czech wildlife trade legislation...

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Masters in Science. Johannesburg, September 2017. / Sable antelope numbers have been declining in protected areas of South Africa and they are listed as Vulnerable in the National Red List Assessment. In Kruger National Park, since 1986, the abundance of sable antelope has declined from 2240 to just under 400 individuals in 2014, making them at risk of local extirpation. The aim of the study was to explore some of the possible explanations, not explored before, for sable antelope (Hippotragus niger) perceived decline in the Kgaswane Mountain Reserve (KMR), in the North-West Province of South Africa. I therefore looked at assessing sable antelope use of space in relation to ‘high risk’ areas as determined by distances to fences, campsites and roads; determining the seasonal variations in the nutritional status of sable antelope; estimating calves recruitment, survival and population sex ratio. To achieve these objectives two sable antelope heifers were collared in the reserve, one from the ‘vlei’ herd and one from the ‘woodland’ herd. Both herds avoided ‘high risk’ areas, especially areas close to camping huts. The herds made little use of areas where there was lots of human movement. I expected the herds to utilise areas close to fences, especially after security burns along the perimeter of the park, but that was not the case as these areas were little utilised. Both herds preferred the tall grassland type of vegetation. As expected both herds utilised burnt areas and the woodland herd used these areas more than the vlei herd. Faecal crude protein and faecal phosphorus values during the dry season were higher compared to a previous study in KMR, which seems to suggest that currently the sable population in KMR is doing better compared to 2002-2003. Since 2011 until 2014, there were a total of 34 calves born with 15 missing after the study but only one mortality recorded. Therefore the reasons for the missing calves are still unclear. The best way to monitor survival of populations for long term studies would be to mark individuals in a population but unfortunately this was impossible for this study. I expected more females to be born as compared to males and this was not the case as there were more males (20) born than females (14), further indicating that potentially currently the population is doing better than in the past. / MT2018

The state of the populations of many insects is critical in the Czech Republic, other species have already extinct. Among the species balancing at the limit of survival is myrmecophilus Alcon Blue (Phengaris alcon), especially its ecological form (P. alcon f. alcon), which is associated with the Marsh Gentian (Gentiana pneumonanthe) during the early larval stages. The general aim of my work was to evaluate the current distribution of the Alcon Blue butterfly (P. alcon f. alcon) in the Czech Republic, to estimate the size of the remaining populations and to propose a practical action plan for conservation of the species in the Czech Republic. The analysis of the databases showed that the species survives theoretically in 11 localities. The field survey in 2016 revealed, however, that at five other sites a species in the recent past was extinct. The remaining 6 localities are concentrated in Southwestern Bohemia on a total area of only 20 hectares. Two population is however close to extinction. The cause of local extinction of Alcon Blues was the extinction of host plants. The main factors influencing the size of butterfly populations in the last localities were the abundace and vitality of host plants (number of fertile shoots, height). Part of my work was an attempt to reintroduce Alcon Blue to a...

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Invasive species introductions are associated with negative economic and environmental impacts, including reductions in native species populations. Successful invasive species populations often grow rapidly and a new food web equilibrium is established. Invasive, predatory northern pike (Esox lucius; hereafter pike) were detected in 2010 in Utah Lake, UT, a highly-degraded ecosystem home to the endemic, endangered June sucker (Chasmistes liorus). Here we test whether pike predation could hinder the restoration efforts of June sucker using the number of June sucker consumed by pike at various population densities as our metric. More specifically, we considered pike density at which the population could consume all June sucker stocked a critical threshold. Currently the number of naturally recruited June sucker is drastically lower than the number stocked. Thus, the metric we used to determine whether the pike population could hinder the June sucker restoration efforts is the number of pike that could consume the number of June sucker stocked. We combined pike growth and foraging observations with an energy-budget, bioenergetics consumption model to quantify lake-wide pike predation on June sucker. We also used an age-structured density dependent population model to estimate the pike population growth trajectory under various mitigation scenarios. Of 125 pike, we found an average pike consumes 0.8-1.0% June sucker and 40% sport fish. According to our bioenergetics model simulations, a population of adult pike at a very high density (60 pike per hectare) has the potential to consume nearly 6 million age-0 June sucker per year, which is likely more June sucker consumed than exist in the environment. In addition, our model suggests that an adult pike density greater than 1.5 pike per hectare has the potential to consume all June sucker stocked annually. Our age-structured population model suggests the pike population will reach equilibrium around 2026 at between 8 and 12 adult pike per hectare with the potential to consume between 0.8 and 1.2 million age-0 June sucker per year, respectively. The growing pike population could hamper restoration efforts and threaten endangered June sucker, a population with a mere 2,000 adults, in jeopardy of extinction. Our findings not only inform pike management efforts, but also highlight the importance of allocating resources toward habitat restoration to provide refuge for juvenile June sucker from predation, preventing the spread of aquatic invasive species, and the need for aquatic invasive species education.