Estimating damage caused by wild animals to crops by comparing yields

Wachsende Populationen großer Pflanzenfresser haben in den letzten Jahren erhebliche Schäden an Nutzpflanzen verursacht. Verschärft wird die Situation durch das Fehlen verlässlicher Methoden zur Bestimmung des Schadensausmaßes und zur anschließenden Berechnung der Entschädigung für die zerstörten Ernten. In dieser Studie haben wir die Bedingungen und Möglichkeiten für die Anwendung der Methode zur Abschätzung der durch Wildtiere verursachten Schäden definiert, die auf dem Vergleich der Erträge in geschädigten und nicht geschädigten Gebieten basiert. Diese Methode ist ein guter Kompromiss zwischen Zeitaufwand und Genauigkeit der Schadensermittlung. Die vorgeschlagene Methode deckt auch Wettbewerbsprobleme (unbeschädigte Pflanzen mit eliminierter Konkurrenz können einen erhöhten Ertrag haben) und Wachstumskompensation ab (z. B. wenn die Pflanze in einem frühen Wachstumsstadium beschädigt wird), die mit den derzeit verwendeten Methoden nicht objektiv bewertet werden können. Diese Methode ist auch für die Schadensbestimmung einer Vielzahl von landwirtschaftlichen Kulturen geeignet. Sie muss jedoch in Zukunft durch weitere Studien weiterentwickelt werden. Bei der beschriebenen Methode handelt es sich um ein Gedankenexperiment. Sie muss in der Praxis getestet werden, um ihre Genauigkeit und Komplexität mit anderen Methoden zu vergleichen.Growing populations of large herbivores have caused significant damage to crops in recent years. The situation is exacerbated by the lack of reliable methods for determining the extent of the damage and for the subsequent calculation of the compensation for the destroyed crops. In this study, we defined the conditions and options for application of method for estimating damage caused by wild animals, which is based on comparison of yields in damaged and undamaged areas. This method is a good compromise between time consumption and accuracy of the damage determination. The proposed method also covers competition problems (undamaged plants with eliminated competition may have an increased yield) and growth compensation (for example when the plant is damaged at an early stage of growth) that the currently used methods could not objectively evaluate. This method is also suitable for determining the damage of a wide range of agricultural crops. The method described is a thought experiment and needs to be tested in practice to compare its accuracy and complexity with other methods

History of the Moravian branch of house Žerotín until the late Middle Ages.

(česky): Původních moravských šlechtických rodů, které se v průběhu dějin zařadily mezi vysokou šlechtu není mnoho. Jedním z nich je rod Žerotínů, jehož počátkům a vývoji do počátku 15. století je věnována následující práce. První písemné zmínky o rodu pocházejí z konce 12. století, kdy je již patrná jejich vazba ať už na moravského markraběte či českého krále, v této době pro šlechtu typická. Ve 13. století pak dochází k první fázi rozšíření rodových držav a také k rozrůstání původního rodu Bludoviců do dvou větví - jičínské, vymřelé na počátku 14. století a šumvaldské, která v průběhu 14. století získala ves Žerotín, po které se rod později psal. V celém sledovaném období nepřekročil rod oblast Moravy, dokázal se však v několika případech prosadit do struktur zemské správy, ať už ve správě zeměpanských měst, nebo v oblasti soudní apod. Předci rodu Žerotínů tak nestáli stranou a z pramenů je patrný jejich kontakt s předními církevními a světskými představiteli Moravy, potažmo celého království, i když poněkud ojediněle. V průběhu 14. století se pak stále zřetelněji odděluje větev šumvaldská od žerotínské a díky moravským zemským deskám, lze také rekonstruovat nakládání rodu s majetkem, který až na několik výjimek nedosahoval velkého územního rozsahu.(in English): There are not many of the original Moravian noble families that have been ranked among the high nobility in history. One of them is the Žerotín family, whose origins and development until the beginning of the 15th century is devoted to the following work. The first written mention of the family comes from the end of the 12th century, when their connection to the Moravian Margrave or the Czech King, typical for the nobility, is already evident. In the 13th century, the first phase of the expansion of family possessions and the expansion of the original family of Bludovicové into two branches - jičínská, which at the beginning of the 14th century died out and the šumvaldská, which in the 14th century acquired the village of Žerotín, after which the family later wrote. Throughout the period under review, the family did not exceed the Morava region, but in several cases it managed to assert itself into the structures of the provincial administration, whether in the administration of landlords or in the judicial area, etc. The ancestors of the Žerotín family did not stand aside and their contacts with the prominent ecclesiastical and religious communities, secular representatives of Moravia, or the whole kingdom, were evident, though sometime sporadically. In the course of the 14th...Ústav českých dějinInstitute of Czech HistoryFaculty of ArtsFilozofická fakult

Evaluation of Damage to Forest Tree Plantations by Wild Boar in the Czech Republic

Wild boar (Sus scrofa) populations in Central Europe have been growing long-term, and damages to crops and forests where boars damage freshly planted tree seedlings are growing too. In addition to having a significant economic impact, these damages worsen the prospect of successful restoration of bare land. This study presents an analysis of damage to tree seedling plantations caused by wild boar in the Czech Republic. We used data from an extensive questionnaire survey among forest owners, our own survey of the extent of damage in model areas, and experiments in locations with a large boar population. Damage to plantings is a widespread phenomenon, and up to 80% of planted trees may be damaged in heavily affected locations. The wild boar does not differentiate between bareroot or containerized seedlings or tree species. Trees were often simply pulled out, without any traces of damage to the root system. Wild boar preferences were not affected by the composition of the substrate of containerized seedlings. Seedlings were damaged most often during the 4 weeks after planting; after this period, the risk of damage fell considerably. Based on the obtained data, we estimated that the damage caused by wild boar rooting out seedlings in 2019 throughout the Czech Republic amounted to $3,199,200 USD, which is equivalent to$122 USD per km2 of forest land. As we are not currently aware of any method of protection against this damage, the most expedient solution seems to be the reduction of the wild boar population, as well as to monitor and protect freshly established cultures, for a period of at least 4 weeks after planting

Winter Food Availability for Wild Herbivores Depending on the Type of Forest Regeneration

This study compares the amount of available biomass for wild herbivores (red deer (Cervus elaphus L.), roe deer (Capreolus capreolus L.), and hare (Lepus europaeus Pallas)) depending on three different types of forest silvicultural systems-presented using the example of beech and spruce stands in wintertime. During the winter period, spruce provided ten times more biomass for herbivores than beech. However, beech provided more metabolizable energy, 7.38 MJ/kg on average, whereas spruce only provided 6.57 MJ/kg. From the point of view of "risk of damage by herbivores", artificial regeneration suffered the worst damage after using the Clear Cutting method of forest regeneration, as there was the least amount of biomass available, and thus, herbivores caused the greatest damage. On average, 12% of shoots were damaged in clearings. Most at risk was young forest vegetation up to 1 m tall. In summer, the area was overgrown with available plants, but in winter, the herbivores focused mainly on eating woody shoots. Damage to the natural regeneration when using the Shelterwood Cutting and Strip Cutting regeneration methods ranged up to 3%. At the same time, a high amount of available biomass was measured there, most likely due to its frequent natural regeneration. Thus, both types of trees regenerated in this way were not as susceptible to damage by herbivores as when regenerated using the Clear Cutting method.O

Feeding Behaviour of Eurasian Beavers (Castor fiber) Along Small Streams in an Agricultural Landscape

In areas with high population density, the Eurasian beaver may be forced to utilise sparsely forested landscapes where living conditions may not be optimal for the species. Here, we examine the feeding strategy of Eurasian beavers along a number of small (mainly) forested streams in the Czech agricultural landscape. Diet availability in these sparsely forested landscapes is characterised by a lack of woody plants but a large supply of herbaceous vegetation, including agricultural crops grown close to the watercourse. The beaver has adapted to such conditions by building dams on low-water streams, allowing it to move between scattered diet resources. In winter, the main dietary component was woody plants (70% V), with species normally neglected in optimal sites (e.g. Acer negundo, Prunus spp.) taken in the absence of more favoured species (e.g. Salix spp., Populus spp.), the remaining 30%V consisting of herbaceous vegetation. In summer, however, the main component in the diet was herbaceous vegetation (90% F), which included agricultural crops (56% V). Where there were not enough trees, the beaver tended to leave its summer territory and move to stretches with denser tree stands. Thus, beavers in sparsely forested agricultural landscapes have adapted by utilising the diverse supply of herbaceous vegetation, though its continued presence in the landscape is still primarily dependent on sufficient stocks of woody plants, which the beaver needs to survive winter.O

Intensive Hunting Pressure Changes Local Distribution of Wild Boar

Wild boar (Sus scrofa) is now an important species of wild ungulates in Central Europe. Next to conflicts of wild boar with agriculture, the main threat of wild boar presence lies in the expansion of African swine fever across Europe. The regulation of the wild boar population is complicated by the high reproduction rate and intelligent behavior of the species, which limits hunting effectiveness. We analyzed the spatial behavior of wild boar in an environment with a lack of natural food resources. The study area consisted of a forest complex (1,283 ha) with 2 areas. In the “risk” area, wild boar were intensively hunted, and in the “refuge” area, the hunting pressure was much lower. The distribution of wild boar was not regular within the study area. The wild boar density was higher in the refuge area than in the risk area. Even in times of food shortage, wild boar avoided the area where obtaining quality food was associated with a high risk of being killed. The conclusion applies to the winter season and an environment where the wild boar can become sufficiently fattened in the crop fields in the summer. For effective control of wild boar populations, it is therefore essential to organize the coordination of hunting pressure evenly in large areas

The Influence of Forestry Management on the Selection of a Non-Vegetative Diet by the Eurasian Beaver (Castor fiber L.)

Native ecosystems have been transformed by humans into cultural landscapes, resulting in the disruption of natural interactions, with some species unable to adapt and disappearing from such landscapes. Other species were able to adapt their behavior to current environmental conditions. In some places, forest management has gradually transformed native diversified forests into stands converted for the greatest profit in the wood matter, thereby affecting the food availability for herbivores, among them the Eurasian beaver (Castor fiber Linnaeus, 1758). This study summarizes knowledge on non-vegetation diet selection by beavers in commercial and natural forests in the Czech Republic. A sample size of 25,723 woody plant specimens checked in 288 forest stands showed that beavers prefer willow, poplar, or hazel, but where these are less available, commercial tree species such as oak may dominate the diet and cause economic losses in forestry. Significant differences were also observed in a preference for different trunk diameters and distances from water in different types of stands. In terms of stand types, commercial monocultures are the most felled, while the probability of felling decreases with the age of stands. Based on these results and discussion, it is suggested that commercial forest stands including economically valuable woody plant species (e.g., oak, ash) could be protected through appropriate management measures, such as increasing the proportion of deciduous softwood stands along the riverbanks, which would distract the beavers from commercial woody plant species.O

Reproductive characteristics of wild boar males (Sus scrofa) under different environmental conditions

The wild boar population has been on a permanent increase over the last decades, causing conflicts with the requirements of modern human society. Existing effort to stabilize wild boar numbers generally fails with one of the causes being the high reproductive potential of wild boar. The aim of this study was to assess the onset of sexual maturity in wild boar males with regard to age, physical frame and environmental conditions on the basis of testicle development and sperm production. This study assessed the dimensions of gonads and the occurrence of sperm in boars caught during common hunts. Environmental conditions were found as an important factor for growth and sexual maturity of wild boar males. The body weight was a more important factor for sperm production than the age of young wild boar males. The weight threshold for sperm production in the testes was 29 kg of live weight, which corresponds to 6 months of age on average. This study has proven that environmental conditions are a significant factor affecting the physical development of male wild boars, more specifically the growth rate of their body frames and the onset of sexual maturity. In a better quality environment boars grow faster and enter puberty at an earlier age. Poor food supply and/or high hunting pressure result in slower body and testicular growth, as well as the production of sperm at a later age (approx. 2-3 months later).O

Feeding ecology of ungulates and browsing damages

The damages caused by ungulates are mostly dependent on the attractivity of their food supply

The natural seasonal changes in the food choice and digestive tract of wild ruminants

Herbivore populations all over Europe have been strongly influenced by human activities. A combination of harvest, changes in forest structure, supplementary feeding, predator extirpation and others factors have led in most cases to increases of their populations and a severe impact on the composition and structure of the forest vegetation. The food choice of free living ungulate species is strongly influenced by season and animal species and changes in diet composition and quality cause the changes in the digestive tract. Effective management of ungulate populations and forest ecosystems should be based not only on detailed information about the impact of deer browsing and the number of deer to harvest but also on the density of deer species, the food supply, the structure of diets consumed by individual species, attraction and quality of the individual components of food supply the total quality of food taken and seasonal changes in digestive tract