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Hothorn T.,Ludwig Maximilians University of Munich | Muller J.,Nationalparkverwaltung Bayerischer Wald | Schroder B.,University of Potsdam | Kneib T.,Carl von Ossietzky University | Brandl R.,University of Marburg
Ecological Monographs | Year: 2011

Species distribution models are an important tool to predict the impact of global change on species distributional ranges and community assemblages. Although considerable progress has been made in the statistical modeling during the last decade, many approaches still ignore important features of species distributions, such as nonlinearity and interactions between predictors, spatial autocorrelation, and nonstationarity, or at most incorporate only some of these features. Ecologists, however, require a modeling framework that simultaneously addresses all these features flexibly and consistently. Here we describe such an approach that allows the estimation of the global effects of environmental variables in addition to local components dealing with spatiotemporal autocorrelation as well as nonstationary effects. The local components can be used to infer unknown spatiotemporal processes; the global component describes how the species is influenced by the environment and can be used for predictions, allowing the fitting of many well-known regression relationships, ranging from simple linear models to complex decision trees or from additive models to models inspired by machine learning procedures. The reliability of spatiotemporal predictions can be qualitatively predicted by separately evaluating the importance of local and global effects. We demonstrate the potential of the new approach by modeling the breeding distribution of the Red Kite (Milvus milvus), a bird of prey occurring predominantly in Western Europe, based on presence/absence data from two mapping campaigns using grids of 40 km2 in Bavaria. The global component of the model selected seven environmental variables extracted from the CORINE and WorldClim databases to predict Red Kite breeding. The effect of altitude was found to be nonstationary in space, and in addition, the data were spatially autocorrelated, which suggests that a species distribution model that does not allow for spatially varying effects and spatial autocorrelation would have ignored important processes determining the distribution of Red Kite breeding across Bavaria. Thus, predictions from standard species distribution models that do not allow for real-world complexities may be considerably erroneous. Our analysis of Red Kite breeding exemplifies the potential of the innovative approach for species distribution models. The method is also applicable to modeling count data. © 2011 by the Ecological Society of America.


Meyer C.,Ludwig Maximilians University of Munich | Heurich M.,Nationalparkverwaltung Bayerischer Wald | Huber I.,Bayerisches Landesamt fur Gesundheit und Lebensmittelsicherheit | Krause G.,Bundesinstitut For Risikobewertung | And 2 more authors.
Berliner und Munchener Tierarztliche Wochenschrift | Year: 2014

The use of antimicrobial agents is responsible for the emergence and spread of antibiotic resistant bacteria. Nevertheless, multiresistant bacteria have been found in animals that have never been exposed to antimicrobial agents. Wild animals that are carriers of methicillin-resistant organisms represent a hazard since they can transmit their bacteria to other animals and to humans. In the hunting season 2009/2010 nasal swabs of 98 red deer and 109 wild boars were examined for the presence of methicillin-sensitive and methicillin-resistant staphylococci. From each wild boar methicillin-susceptible staphylococci (Staphylococcus aureus in 28% and Staphylococcus spp. in 72% of the animals) were isolated. In red deer the detection rate of Staphylococcus (S.) aureus and methicillin-susceptible staphylococci was 49% and 17%, respectively. The occurrence of S. aureus was significantly higher (p<0.05) in red deer than in wild boars. Methicillin-resistant staphylococci were not found. However, in one third of the red deer, methicillin-resistant bacteria of the genus Enterococcus spp. and Bacillus spp. were isolated. The results of the present study indicate that wildlife, especially red deer are an important reservoir for S. aureus and that the upper respiratory tract of red deer is regularly colonised with methicillin-resistant bacteria such as Bacillus spp. and Enterococcus spp. Primarily, commensal bacteria are harmless to human health, however, red deer may be a reservoir for antibiotic-resistant bacteria. © 2014 Schlütersche Verlagsgesellschaft mbH & Co. KG.


Fischer H.S.,TU Munich | Winter S.,TU Munich | Lohberger E.,Amt fur Landwirtschaft und Forsten Landau a.d.Isar | Jehl H.,Nationalparkverwaltung Bayerischer Wald | Fischer A.,TU Munich
Folia Geobotanica | Year: 2013

The potential natural vegetation (PNV) is a tool for landscape planning, nature preservation and the assessment of naturalness. It is mostly constructed by the application of expert knowledge. This paper shows the advantages of using a more sophisticated and formalized PNV construction that overlays vegetation types and site factor maps by applying a Bayes model and herewith improving existing PNV maps solely based on expert knowledge. The investigation was conducted in the forest complex of the Bavarian Forest National Park (Germany) and the adjacent Šumava National Park (Czech Republic). The project reached two major results: (1) The existing heterogeneous country-specific databases of natural site conditions and of vegetation types could be adapted to each other to construct a solid scientific basis to deduce a PNV map. The habitat requirements of the occurring harmonized vegetation types can now be quantitatively described in a formalized way. (2) The combination of terrestrial PNV mapping and numerical modeling allows the synthesis of the views of the different experts that generated the maps used for model calibration. However, the modeled map loses the details of the expert-based map that cannot be derived from the underlying site maps. A common modeled PNV map of both national parks covering an area of about 92,000 ha was created. While the former expert-based PNV maps display breaks along the country border, the modeled PNV presents a harmonized view based on the common database of both national parks. © 2012 Institute of Botany, Academy of Sciences of the Czech Republic.


Barancekova M.,Academy of Sciences of the Czech Republic | Krojerova-Prokesova J.,Academy of Sciences of the Czech Republic | Sustr P.,NP and PLA Sumava | Heurich M.,Nationalparkverwaltung Bayerischer Wald
European Journal of Wildlife Research | Year: 2010

The composition of roe deer diet in the Bohemian Forest was analysed with the aim to assess its role in forest habitat altered by bark beetle outbreaks and wind calamities. The annual diet of roe deer was studied at both, Czech and German, sides of the Bohemian Forest using microscopic analyses of faeces. On average, the largest part of the roe deer diet consisted of forbs (32%), followed by three other components-grasses (17%), coniferous trees (13%) and broadleaved trees (11%). Overall the results show that the composition of roe deer diet in the Bohemian Forest is that of a typical concentrate selector. © 2009 Springer-Verlag.


Nel P.,CNRS Systematics, Biodiversity and Evolution Institute | Nel P.,Agro ParisTech | Schmidt A.R.,University of Gottingen | Bassler C.,Nationalparkverwaltung Bayerischer Wald | Nel A.,CNRS Systematics, Biodiversity and Evolution Institute
Acta Palaeontologica Polonica | Year: 2013

The new fossil thrips Uzelothrips eocenicus P. Nel and A. Nel sp. nov. (Thysanoptera: Uzelothripidae) is described from two lowermost Eocene amber-preserved specimens (one macropterous and one apterous). The family Uzelothripidae is only known so far from a single extant species, Uzelothrips scabrosus. The fossils differ from the extant species only by the antennal segments III and IV, which appear distinctly separated instead of being fused as in the in the extant U. scabrosus. Dark-coloured hyphae and conidia of the Dothideomycetes (Ascomycota) which are likely to belong to the sooty moulds (Capnodiales) are attached to the apterous fossil specimen. We consider this arthropod-fungus association not to be accidental since these fungi are also found in extant specimens of these uzelothripids, suggesting very specific long-term interactions and strong habitat specificity. © 2013 P. Nel et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Hofner B.,Friedrich - Alexander - University, Erlangen - Nuremberg | Muller J.,Nationalparkverwaltung Bayerischer Wald | Muller J.,TU Munich | Hothorn T.,Ludwig Maximilians University of Munich
Ecology | Year: 2011

Flexible modeling frameworks for species distribution models based on generalized additive models that allow for smooth, nonlinear effects and interactions are of increasing importance in ecology. Commonly, the flexibility of such smooth function estimates is controlled by means of penalized estimation procedures. However, the actual shape remains unspecified. In many applications, this is not desirable as researchers have a priori assumptions on the shape of the estimated effects, with monotonicity being the most important. Here we demonstrate how monotonicity constraints can be incorporated in a recently proposed flexible framework for species distribution models. Our proposal allows m notonicity constraints to be imposed on smooth effects and on ordinal, categorical variables using an additional asymmetric L2 penalty. Model estimation and variable selection for Red Kite (Milvus milvus) breeding was conducted using the flexible boosting framework implemented in R package mboost. © 2011 by the Ecological Society of America.


Heurich M.,Nationalparkverwaltung Bayerischer Wald | Ochs T.,TU Munich | Andresen T.,TU Munich | Schneider T.,TU Munich
European Journal of Forest Research | Year: 2010

The survey and continuing inventory in the Bavarian Forest National Park of deadwood areas resulting from a spruce bark beetle calamity are being performed by means of visual evaluation of colour infrared aerial photographs. With the aid of the object-oriented image analysis software eCognition, it was possible to develop a partially automated method for this purpose. In order to verify the classification results, a test area was classified, and the results compared with those obtained by the previously used method. In addition, the classification results from two consecutive years were compared, and accuracy assessment methods were used to scrutinize the results. Classification in the deadwood areas yielded a total classification accuracy of 91.5%. In regard to objectivity and degree of detail, the newly developed method is significantly superior to the former method, which is based on visual interpretation with a stereo workstation. One problem, however, was the insufficient spatial accuracy of the respective orthophotos. Because of this, it was not possible to detect changes over the course of specified time intervals. Therefore, a practical application of this method would require that the orthophotos from various dates or times be precisely spatially assigned. This requirement can be achieved with the production of new orthophotos. © Springer-Verlag 2009.


Gunther S.,Nationalparkverwaltung Bayerischer Wald | Heurich M.,Nationalparkverwaltung Bayerischer Wald
Allgemeine Forst- und Jagdzeitung | Year: 2013

National parks, as a category for protected areas, are a relatively recent creation. With the exception of the Swiss National Park (1914), all other European national parks were established after 1970. According to proclaimed goals, natural processes in the national parks are to be allowed to develop free of human interference. The methods by which these aims are to be achieved in respect to the management of large wild animals are a subject of much controversy: hunting traditions and forestry practices play important roles and generally accepted management standards are nonexistent. In view of these facts, we undertook this project to develop a set of criteria that can be used to assess methods for the management of red reer in regard to their approximation of natural conditions and that are suited to evaluate the quality of protected areas. Near natural areas are defined as areas in which the animals are not fed, hunting is not allowed, and populations are regulated by natural processes. In order to assess the current situation in the central European national parks, questionnaires were sent to 20 national park administrations in countries that have red deer populations. A total of 16 national parks took part in the study (table 1). Questions focused on features of the protected area, the red deer population characteristics, types of management measures, and related general conditions. Red deer management practices (table 4) in the individual protected areas were then evaluated with the aid of criteria that had been developed for determining the degree to which they emulate natural conditions (table 2). As indicated by the results, red deer are managed to a great or very great degree in most of the protected areas (figure 2). This is not in accordance with the proclaimed goals of national parks. With the exception of the Swiss National Park, red deer Populations are strongly manipulated in all of the other protected areas that participated in this study, especially in regard to population development (regulatory culling, feeding), spatial-temporal behaviour (stress due to hunting and recreational activities), and genetics (selection as an effect of hunting). In contrast, mechanisms of natural regulation, such as those caused by the presence of large predators, have only been of subordinate significance.


Krop-Benesch A.R.,Leibniz Institute for Zoo and Wildlife Research | Berger A.,Leibniz Institute for Zoo and Wildlife Research | Hofer H.,Leibniz Institute for Zoo and Wildlife Research | Heurich M.,Nationalparkverwaltung Bayerischer Wald
Italian Journal of Zoology | Year: 2013

The investigation of activity patterns provides crucial information on the ecology of a species, yet there are very few long-term data available from free-ranging species. Here, we present the first continuous activity data of free-ranging roe deer covering an entire calendar year. Six male and five female roe deer in the National Park Bavarian Forest, Germany, were equipped with GPS collars containing a two-axis accelerometer. Activity data were analysed for daily activity patterns and their seasonal changes. Daily activity patterns resembled the patterns described in earlier VHF-telemetry based studies, but instead of a pure active/inactive discrimination, the level of activity was obtained continuously, allowing a more precise study of activity intensity.Activity was observed at all daytimes, but was most intense at twilight. These twilight peaks were less pronounced in winter. The intensity of activity showed stronger seasonal changes than the number and duration of activity bouts. Mean daily activity levels and the number of activity peaks per day were lower in winter than in spring and summer. Mean duration of activity peaks did not change during the year. At all seasons, activity had a significant 24-hour periodicity, but the time of its emphasis changed. The roe deer was most diurnal during winter, and most nocturnal in autumn. In spring and summer, activity was evenly distributed between day and night. Seasonal changes in activity could be explained by seasonal changes in physiological parameters and in environmental changes, especially food supply and climate. © 2013 Copyright 2013 Unione Zoologica Italiana.


Hothorn T.,Ludwig Maximilians University of Munich | Muller J.,Nationalparkverwaltung Bayerischer Wald
Forest Ecology and Management | Year: 2010

Browsing by free-living ungulates is a serious threat to forest regeneration. Although predictors of browsing and potential consequences are well researched, less information is available in the scientific literature about possible solutions to the problem. We investigated whether a large-scale game management system in a traditional sport hunting culture has the potential to effectively reduce browsing damage. Our analysis was based on browsing survey data from 2006 and 2009 covering more than 25,000km2 in Bavaria, Germany. After an initial assessment of browsing damage throughout Bavaria in 2006, game management plans were altered, and the effect of this intervention was assessed in 2009. Browsing damage clearly declined in 2009 in areas where the suggested deer harvests were increased in 2006 game management plans. This is the first report of a successful implementation of a large-scale game management system aiming at reducing browsing damage to facilitate unfenced forest regeneration. © 2010 Elsevier B.V.

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