BUND Naturschutz

Abstract Knowledge of the range of bird vocalisations is crucial not only for estimating the range of species acoustic communication but also for the detection radius of an observer in monitoring projects and expert assessments. Using calibrated sound recordings and parallel acoustic localisation, we assessed three methods of determining the sound pressure level for four species of rail [Corn Crake ( Crex crex ), Water Rail ( Rallus aquaticus ), Spotted Crake ( Porzana porzana ), Little Crake ( Zapornia parva )], whose calls differ significantly in temporal organisation and spectral composition. We calculated sound propagation over long distances, taking into account spherical propagation losses and atmospheric absorption. Atmospheric absorption was calculated including all frequencies contained in the signal. In the case of the Corn Crake in particular, we demonstrated that all spectral components of the signal must be considered when estimating its range. To ensure comparability between studies, we recommend establishing a reference library containing calibrated sound recordings . The results were discussed in the context of their significance for the acoustic communication of the species.

Existing literature on pediatric traumatic brain injury (TBI) transfers to higher-level trauma centers is limited. Most studies focus on inhospital mortality and neurosurgical intervention rates, often overlooking outcomes such as early discharge without neurosurgical intervention, intensive care unit length of stay, and discharge disposition. To assess the impact of transfer to a higher-level trauma center on clinical outcomes of pediatric severe TBI patients. This retrospective cohort study used the American College of Surgeons Trauma Quality Improvement Program database between 2017 and 2023 to evaluate pediatric trauma patients with isolated severe TBI transferred from lower-level to higher-level trauma centers. The primary outcome was the odds of discharge within 24 or 48h without requiring neurosurgical intervention and rates of neurosurgical intervention. Secondary outcomes included emergency department and 24-h mortality, initial and repeat computerized tomography scan rates, intensive care unit length of stay, ventilator-free days, and discharge home. Of the 4,154 pediatric patients with isolated severe TBI, 1,723 (41.5%) were transferred, and 2,418 (58.2%) were not. Transferred patients had a 42% lower odds of discharge within 24h without neurosurgical intervention (OR: 0.58, 95% CI [0.41, 0.80], p <.001), were more likely to undergo neurosurgical intervention (OR: 1.26, 95% CI [1.04, 1.53], p =.016), and were more likely to be discharged home (OR: 1.58, 95% CI [1.30, 1.92], p <.001). Mortality rates did not differ significantly between groups. Transfer to higher-level trauma centers is associated with increased neurosurgical intervention and higher rates of discharge home in pediatric patients with severe TBI, without differences in mortality.

Abstract The garden dormouse (Eliomys quercinus) inhabits a wide range of habitats, from urban areas in warm temperate lowlands to cool mountain ranges. Despite its adaptability, it has largely disappeared from its former range. While most forest populations in Germany are declining, some populations in cities remain stable. To better understand the ecology of this endangered species, VHF telemetry studies were conducted. Between May and September in 2021, 2022, and 2023, 19 adult individuals (7 males, 12 females) were tracked between 15 to 79 days. The animals were assigned to one of three habitat types: ‘Urban’ (entirely human-modified areas, n = 7), ‘Forest’ (forest habitat with minimal human presence, n = 6), and ‘Mixed’ (a combination of forest and human-modified areas, n = 6). Garden dormice had the largest home ranges (MCP100) in ‘Forest’ habitats (4.06 ha) followed by ‘Mixed’ (1.2 ha) and ‘Urban’ habitats (0.56 ha). They preferred structures with high coverage and proximity to food resources, such as structurally rich plant communities (‘Urban’), rock crevices and ruderal shrub vegetation, including berry bushes (‘Forest’). Nest sites offered protection from predators and a stable microclimate, and were predominantly located in buildings (‘Mixed’, ‘Urban’) and rock crevices (‘Forest’). They were changed frequently. Garden dormice occupied smaller home ranges in areas where human-provided resources were concentrated in a small space. Although garden dormice habitats and the resources they use differ in appearance, they fulfill the same ecological needs: sufficient food, safe movement through the habitat and secure nest sites.

BackgroundConspicuous color patterns are traditionally believed to advertise the toxicity of prey to potential predators. However, many aposematic species show drastic variation in coloration, indicating the possibility of other functions of coloration such as intraspecific communication. To study these other functions, we can investigate the influence of intrinsic (e.g., sex) and external factors (e.g., climate) on color variation. We used the aposematic European fire salamander (Salamandra salamandra) to study drivers of variation in the yellow-to-black ratio of the dorsal coloration based on citizen science data available in a new online database.ResultsOur results suggest a widespread sexual dichromatism in fire salamanders in Germany with males displaying a larger yellow-to-black ratio, i.e. are more yellow, than females. This dichromatism persisted even after correcting for a sex-difference in body shape that accounts for some of the variation in the yellow-to-black ratio. Among six investigated putative drivers of this color variation, the proportion of the aposematic yellow coloration increased with latitude but showed no association with other environmental variables such as temperature or the productivity of the habitat.ConclusionsIntegrating citizen science data in this study enabled a comparison of fire salamander populations across large parts of their distribution and highlights widespread sexual dichromatism. Future studies should further investigate potential mechanisms of mate choice in fire salamanders and other selective forces on coloration such as differential predation pressure between both sexes or the role in crypsis. Lastly, multi-national studies supported by citizen science data could fully unravel the extent of color variation in this species.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12862-025-02461-0.

ZusammenfassungDer Nordamerikanische Waschbär gehört zu den gebietsfremden Vertretern der deutschen Raubsäugerfauna und ist eine der am stärksten omnivor ausgerichteten Säugetierarten weltweit. Der seit Ende der 1930er-Jahre in Deutschland angesiedelte Kleinbär wird in den letzten Jahren vermehrt als Gefahr für einheimische Tierarten sowie als potenzieller Krankheitsüberträger wahrgenommen. Aufgrund seiner anpassungsfähigen, urbanophilen Lebensweise nehmen auch Mensch-Waschbär-Interaktionen und damit verbundene Problemfelder im Siedlungsraum zu. Der Artikel fasst den aktuellen Kenntnisstand zu den Auswirkungen der Waschbärenbesiedlung in Deutschland zusammen, gibt einen Überblick zum rechtlichen Status des Neubürgers und stellt konkrete Managementmaßnahmen und Handlungsempfehlungen als Resultat von Freilandforschung und Praxiserfahrung vor, mit denen die wesentlichen Konfliktfelder nachhaltig und effektiv minimiert werden können.SummaryThe North American raccoon is an introduced carnivore species in Germany and one of the most omnivorous mammal species worldwide. Established in Germany since the end of the 1930s, the procyonid has become increasingly perceived as a threat to native species as well as a potential vector of disease in recent years. Due to its adaptable, urbanophilic lifestyle, human-raccoon interactions and associated problems in settlement areas are also increasing. The article summarises the current state of knowledge on the impacts of raccoon settlement in Germany and provides an overview of the legal status of the newcomer. Concrete management measures and recommendations for action are presented as a result of field research and practical experience. In this way, the areas of conflict caused by the raccoon presence can be minimised sustainably and effectively.

BackgroundThe extent and impact of evolutionary change occurring in natural populations in response to rapid anthropogenic impact is still poorly understood on the genome-wide level. Here, we explore the genetic structure, demographic history, population differentiation, and domestic introgression based on whole genome data of the endangered European wildcat in Germany, to assess potential genomic consequences of the species’ recent spread across human-dominated cultural landscapes.ResultsReconstruction of demographic history and introgression rates based on 47 wildcat and 37 domestic cat genomes suggested late introgression between wild and domestic cat, coinciding with the introduction of domestic cat during the Roman period, but overall relatively low rates of hybridization and introgression from domestic cats. Main population divergence found between an eastern and central German wildcat clade was found to be of rather recent origin (200 y), and thus the likely consequence of anthropogenic persecution and resulting isolation in population refugia. We found similar effective population sizes and no substantial inbreeding across populations. Interestingly, highly differentiated genes between wild cat populations involved in the tryptophan-kynurenine-serotonin pathway were revealed, which plays a role in behavioral processes such as stress susceptibility and tolerance, suggesting that differential selection acted in the populations.ConclusionsWe found strong evidence for substantial recent anthropogenic impact on the genetic structure of European wildcats, including recent persecution-driven population divergence, as well as potential adaptation to human-dominate environments. In contrast, the relatively low levels of domestic introgression and inbreeding found in this study indicate a substantial level of “resistance” of this elusive species towards major anthropogenic impacts, such as the omnipresence of domestic cats as well as substantial habitat fragmentation. While those findings have strong implications for ongoing conservation strategies, we demand closer inspection of selective pressures acting on this and other wildlife species in anthropogenic environments.

Der durch die steigenden Oberflächentemperaturen voranschreitende Klimawandel wird sich zunehmend auf das Wirtschaften auswirken – und damit auch auf die Unternehmen. So konstatierte die Bundesregierung in ihrem zweiten Fortschrittsbericht zur Deutschen Anpassungsstrategie an den Klimawandel, dass sich die mittlere Lufttemperatur in Deutschland im Zeitraum von 1881 bis 2019 um 1,6 °C erhöht hat.