Abstract: European beaver population in Central Europe originated from several refugial populations. Although these populations are currently well-researched, but the manifestations that may reflect genetic variability, are not known. In the Czech Republic there are beavers who spread from Saxony, from Magdeburg refugia, and other stocks that are created by beavers from Austria and Bavaria, or are the offspring of individuals coming from refuges in Poland, Russia, Norway and France. There are many indications that individuals from northern Bohemia (Elbe individuals of the population) have a considerable amount of differences. The aim of this study was to determine the exact age of mortalities beaver from the collection of the Department of Ecology FES. The most accurate estimate of the age is the closing of the basal opening of the tooth root and the sum of cement layers molars, but this method is time-consuming and technically challenging and therefore the work of trying to find another reliable criterion to determine the age of mortalities in the form of intervals of specific characteristics for each age class (juvenil, subadult, adult). Using statistical analysis, I conclude that the most cranial size determination for individuals age the length dimension is LCB (condyobasal length of the skull) and LAZ (zygomatic width of the skull). The most appropriate metristic characteristic to estimate the age appeared weight.

Šio tiriamojo darbo tikslas buvo įvertinti Radviliškio girininkijoje aptiktas upinio bebro (Castor fiber) populiacijas. Tyrimas atliktas 2012 - 2013 metais. Pirmiausia tyrimo metu buvo renkama informacija apie Radviliškio girininkijoje, Linkaičių miško teritorijoje, esančiuose melioracijos grioviuose, įsikūrusias bebravietes, jų gausumą. Taip pat tyrimo eigoje nustatytas bebrų skaičius kiekvienoje aptiktoje bebravietėje. Nustatyta bebrų gyvenamoji aplinka, mitybos įpročiai bei jų padaroma žala miškui. / The aim of this research was to evaluate the detected Eurasian beaver (Castor fiber) population in Radviliškis forestry. The study was accomplished in the year of 2012 - 2013. In the beginning of the study was collected information about the beaver lodges at drainage ditches in Linkaičiai forest teritory, Raviliškis forestry. Also during the investigation was detecded number of the beavers in each beaver lodge.

1871 var bäver utrotad i Sverige, 1922 gjordes den första återintroduceringen i Jämtland. Det dröjde ända till 1960-talet innan bäver återintroducerades i Norrbotten. Återintroduceringarna i Sverige är ett relativt outforskat område och syftet med denna uppsats är att kartlägga återintroduceringarna i Norrbotten som skedde mellan 1960 - 1976. Resultaten som sådana är inte generaliserbara då de första utsättningarna i Norrbotten gjordes avsevärt senare än i övriga län, vilket innebär att aktörer och processer kan ha varit annorlunda. Dock visar denna undersökning på de bakomliggande motiv och restriktioner som fanns, vilket potentiellt kan tillämpas även vid andra återintroduceringar. Av bäverinventeringsmaterialet används endast information gällande Norrbotten, trots att inventeringar över hela Sverige redovisas, vilket gör det möjligt att potentiellt undersöka om samma mönster även gäller generellt. / By 1871 the beaver was extinct in Sweden. The beaver was first reintroduced in the county of Jämtland in 1922 and during the 1960s it was also reintroduced in the county of Norrbotten. This is a relatively unexplored field and the intention is to chart the reintroduction of beavers in Norrbotten between 1960-1976. This essay will not study the reintroductions in general. It will only study Norrbotten during the period mentioned above. The results as such is not generalizable because the first reintroduction in Norrbotten was considerably later than in the other counties, which means that the agents and processes involved may have been different in other parts of the country. However, this survey shows the underlying motivations and constraints that existed and this might be applicable on other reintroductions. In the materials of the beaver inventories only information regarding Norrbotten has been used, even though the inventories contains a chart of the beavers in all of Sweden. It is possible to investigate if these patterns might be generally applicable

Šio darbo tikslas buvo ištirti atsitiktinai padaugintos polimorfinės DNR (APPD) metodu skirtingas Europinio bebro (Castor fiber) subpopuliacijas Lietuvoje. Buvo ištirtos Europinio bebro 4 subpopuliacijose: Mituvos, Vilkaraisčio, Giedraičių ir Rusnės salos. DNR atsitiktinai padaugintų fragmentų polimorfizmas buvo tirtas naudojant 10 pradmenų. Pagal Nei apskaičuotą genetinę distanciją tarp populiacijų, labiausiai genetiškai panašios buvo Giedraičių ir Vilkraisčio subpopuliacijos (0,936), didžiausia genetinė distancija nustatyta tarp Rusnės salos ir Vilkaraisčio subpopuliacijų (0,288). Ištirtos subpopuliacijos grupuojasi į du klasterius: vieną klasterį sudaro Rusnės salos ir Mituvos subpopuliacijos, kitą – Vilkaraisčio ir Giedraičių subpopuliacijos. Europinio bebro subpopuliacijų genetinei įvairovei nustatyti, Popgene programa buvo apskaičiuoti 4 parametrai. Shannon informacinis indeksas svyravo nuo 0,2527 (Rusnės sala) iki 0,3895 (Giedraičiai). Nei genetinė įvairovė svyravo nuo 0,1677 (Rusnės sala) iki 0,2589 (Mituva). Didžiausias nustatytas alelių skaičius buvo Mituvoje (1,8911), mažiausias Rusnės saloje (1,5050). Efektyvus alelių skaičius svyravo nuo 1,2864 (Rusnės sala) iki 1,444 (Giedraičiai). Didžiausia genetinė įvairovė buvo aptikta Mituvos subpopuliacijoje, o mažiausia genetine įvairove pasižymi Rusnės salos subpopuliacija. Daugiausia polimorfinių lokusų buvo aptikta Mituvos subpopuliacijoje (89,11%), o mažiausiai Rusnės salos subpopuliacijoje (50,5%). Nustatėmė, kad... [toliau žr. visą tekstą] / The aim of this study is to evaluate genetic structure of European beavers (Castor fiber) subpopulations from Lithuania using RAPD (Random Amplified Polymorphic DNA) method. We investigated genetic variability of 4 subpopulations from Rusne, Mituva, Giedraiciai and Vilkaraistis. 10 primers were used in this analysis. Acording to Nei‘s genetic identity, the most similar were subpopulations from Giedraiciai and Vilkaraistis (0,936), the highest genetic distance was observed between subpopulations from Rusnes island and Vilkaraistis (0,288). These subpopulations form two clusters: Mituva and Rusnes island forms one cluster and Vilkaraistis and Giedraiciai – another. To evaluate the genetic variation in subpopulations we analysed four parameters. Shannon’s informations index was from 0,2527 in Rusnes island to 0,3895 in Giedraiciai.The highest Nei‘s genetic variaty was observed in subpopulation from Mituva and the smallest in Rusnes island (0,1677).The highest number of alleles was detected in Mituva (1,8911) and the smalest in Rusnes island (1,5050). The efective number of alleles was from 1,2864 in Rusnes island to 1,444 in Giedraiciai. From these parametres we can see that the most genetic diversity is observed in subpopulation from Mituva and the smallest in subpopulation from Rusnes island. We detected that the in Rusnes island 50,5 % of loci were polimorphic, and in subpopulation from Mituva even 89,11% of loci were polimorphic. We found out that molecular diversity is... [to full text]

Managed forest landscapes in Sweden are dominated by boreal coniferous forest and are deficient in broad-leaved trees. Both beavers (Castor fiber) and ungulate browsers prefer broad-leaved trees to conifers, and the interaction between multiple herbivores may have a considerable impact on the recruitment of deciduous trees in riparian areas. To evaluate the relative importance of beavers and browsers on tree recruitment, I conducted an inventory of broad-leaved tree species at five beaver sites in Färnebofjärden National Park, Sweden. At each site, five transects were established perpendicular to the shoreline in the riparian zone, resulting in a grid of 35 sample plots at each beaver site. Foraging activity of both beavers and browsers (e.g. ungulates) was concentrated to a narrow band in the riparian zone and there was a decrease in the proportion of beaver-cut and browsed trees further away from the shoreline. Beavers preferred birch (Betula spp.) and grey willow (Salix cinerea) while browsers preferred oak (Quercus robur). Beavers targeted larger trees while browsers targeted seedlings <1 cm in diameter. Old-growth trees of high conservation value, such as aspen (Populus tremula) and birch, are at risk to be cut by beaver, yet long-term protection of broad-leaved stands requires a shift in focus towards strategies that enhance tree recruitment by considering and mitigating pressure from multiple herbivores. / Svenska skogslandskap domineras av boreal barrskog med en brist på lövträd. Både bäver (Castor fiber) och betande klövvilt föredrar lövträd framför barrträd, och interaktionen mellan dessa herbivorer kan ha en betydande påverkan på föryngring av lövträd i strandnära skogar. För att utvärdera den relativa betydelsen av bävrar och betare på trädföryngring så genomförde jag en inventering av lövträdsarter och betestryck vid fem bäverlokaler i Färnebofjärden Nationalpark, Sverige. Vid varje bäverlokal lades fem transekter i rät vinkel mot strandkanten i den strandnära zonen, med provrutor var femte meter längs varje transekt, vilket resulterade i ett nätverk av 35 provrutor vid varje lokal. Både bävrars och betares (dvs. klövvilts) födosökande var begränsat till ett smalt band längs strandkanten, och andelen bävergnagda och betade trädstammar minskade med ökat avstånd från strandkanten. Bäver föredrog björk och gråvide medan betare föredrog ek. Bäver föredrog större träd medan betare föredrog groddplantor <1 cm i diameter. Gamla lövträd som är viktiga att bevara, såsom asp och björk, hotas av bäveraktivitet, men långsiktigt bevarande av lövträdsbestånd kräver ett fokus på strategier som främjar trädföryngring, bland annat genom att beakta och begränsa den sammantagna påverkan av olika herbivorers betning.

Daugiau, kaip 80 % hidrografinio tinklo Lietuvoje sudaro melioracijos kanalai. Daugiau kaip 30 % bebrų populiacijos gyvena šiuose kanaluose. Bebrų veikla neretai trikdo normalų melioracijos sistemų funkcionavimą. Tyrimui pasirinktos dviejuose skirtinguose kraštovaizdžiuose esančios bebravietės (Molėtų bei Panevėžio rajonuose). Šiame darbe buvo tiriama bebraviečių tankumas, pasiskirstymas, erdvinės charakteristikos bei statybinės veiklos intensyvumas melioracijos kanaluose. Nustatytas bebrų poveikio mastas bei šio masto pokyčiai. Ištirtose teritorijose bebrų veikiama pusė melioracijos kanalų linijinio ilgio. Per 10 metų (1995-2005) bebraviečių skaičius melioracijos kanaluose praktiškai nepakito, taigi nekito ir melioracijos sistemoms daromas poveikis. / More than 80 % of hydro-graphical network in Lithuania is composed of drainage channels. More than 30 % of beaver populations in Lithuania live in drainage channels. Beaver activity often dislocates irrigations systems. This research was taken in two different landscapes. Beaver sites were visited in Moletai and Panevezys districts. Density, spread, dimensions and constructional activity were recorded in drainage channels. Also this study shows influence over the environment of changing number in beaver populations. Half of linear lengths of irrigation systems are influenced by beaver activity. The number of beaver sites did not change in a ten year period (1995-2005) as well as did not change the damage caused by beaver activity.

No description available.

The semiaquatic mammals - amongst them the beaver Castor fiber - are inhabitants of the land-water-ecotone, which is characterized by length and low depth.Due to specific adaptations to their habitats, semiaquatic mammals are highly dependent on the specific structures and resources of the ecotone riverbank. Anthropogenic influences on the ecotone riverbank often cause destruction of the resources that leads to a decrease of structural diversity.Being a primary consumer, the beaver mainly uses the water as a medium for locomotion and escape. The equipment of the riverbank, mainly the bankside vegetation, is of great importance concerning foraging. The presence and the quantity of certain biofacts like feeding or cutting places and scent mounds give a hint on the value of different structures and resources of the bankside with regard to certain modes of behaviour. They also give information on different qualities of the used and unused parts of the bankside.Biofacts of beaver-activity were recorded along 20 km of riverbank during a five-year-period. The results of the statistical analysis show that beavers - concerning species-specific mode of behaviour - prefer certain riverbank structures. Biofacts and near-natural structures such as steep bank, riparian forest and willows correlate significantly positive whereas biofacts and anthropogenic structures as slope, farmland or absence of woody plants show significantly negative correlation. There is a strong connection between the number of biofacts - that is use of the riverbank or slope - and structural diversity. Based on these results, an eco-ethological model has been developed which makes it possible to predict behaviour in dependence on the specific structures and resources of the banks and slopes of anthropogenic influenced streams.

The aim of the master diploma work is to investigate origin of Czech populations and genetic variability of almost all Eurasian populations of the European beaver (Castor fiber). For our purposes we collected specimens from Czech populations, reintroduced population in Kirov district in Russia and all European and Asian refugia. At the end of the 19th century the species was on the verge of extinction due to overhunting, surviving only in eight isolated refugial areas. The population size at the end of the 19th century was estimated as 1 200 animals. The number of individuals has increased thanks to the legal protection and reintroductions. The current population size is estimated at 640 000. It is obvious that the populations of beaver have recently undergone severe bottleneck. Beaver was completely extirpated in the Czech Republic in the 18th century. Since the 80th of the 20th century beavers re-established in the Czech Republic due to migration from neighbouring countries and reintroduction programmes, however we knew only little about the origin of beavers in the Czech Republic. I showed that our beavers are derived from individuals in France, Germany, Norway and east Europe. Mitochondrial DNA of Castor canadensis has not been found in Czech beavers. I studied microsatellite loci (first use for...

The submitted M.Sc. thesis describes development in populations of the bird and mammalian species, having been involved in human - wildlife conflicts, particularly of the specially protected species, in the Czech Republic as well as in compensation payments for damages caused on private properties by the selected specially protected wild animal species. At the same time, it compares various tools, applied to solve human - willdife conflicts in the different parts of the world. The study presents information provided by governmental authorities or gained from grey literature, expert databases and scientific papers. Trends both in the development in conflict species populations and in compensation payments were assessed and the relationship between both variables was found. In total, payments for damages caused by conflict wild animal species has been increasing in the Czech Republic since 2000, but trends in the conflict species populations differ from each other, influenced particularly by their bionomics. The analysis performed shows, that the act on the topic is effective only for some of the above wild animal species. For large carnivores, namely the Grey Wolf (Canis lupus), Eurasian Lynx (Lynx lynx) and Brown Bear (Ursus arctos), the above tool does not provide suitable solutions for their...