Reproduktion und Jugendentwicklung von Wildkatzen im Südharz : eine Projektvorstellung

Die Wildkatze (Felis silvestris silvestris) gehört in Deutschland zu den stark gefährdeten Tierarten, in Sachsen Anhalt gilt sie als vom Aussterben bedroht. Grundlage für einen effektiven Wildkatzenschutz sind detaillierte Kenntnisse über die ökologischen Ansprüche der Art. Hierbei sind Informationen über die Lebensraumbedingungen, die den Erfolg der Reproduktion einschließlich der Entwicklung der Jungtiere sicherstellen, von essentieller Bedeutung. Eine Telemetriestudie im geplanten Biosphärenreservat „Karstlandschaft Südharz“ soll dazu beitragen, den Themenkomplex „Reproduktion – Entwicklung – Dismigration“ zu erforschen. Die erfolgreiche Besenderung von jungen Wildkatzen hat erstmals Einblicke in die Jungendentwicklung von Felis sylvestris im Freiland ermöglicht. Dem Totholz im reich strukturierten Laubwald kommt bei der Aufzucht der Jungtiere offenbar eine essentielle Bedeutung zu. Über diese Erkenntnis hinaus gelang es, die Lebensabschnitte, in denen die Jungtiere einem erhöhten Mortalitätsrisiko ausgesetzt sind zu bestimmen und teilweise die Ursachen für die Verluste von Jungtieren zu ermitteln

Wildkatzen und Straßen : Ermittlung von Unfallschwerpunkten im Ostharz

Seit einigen Jahren wird für Teilpopulationen der Wildkatze (Felis s. silvestris) in Deutschland ein positiver Ausbreitungstrend beobachtet. Auch an der Peripherie ihres nördlichen Verbreitungsgebietes, dem Harz, wird die Art wieder häufiger nachgewiesen. Dennoch beschränkt sich die Verbreitung der Wildkatze heute lediglich auf einen Bruchteil ihres ursprünglichen Areals, so dass die Art weiterhin als gefährdet gilt und eines hohen internationalen wie nationalen Schutzes bedarf. Neben der Gefahr einer zunehmenden Hybridisierung mit Hauskatzen (Felis catus), ist heute der Straßenverkehr die häufigste anthropogen bedingte Gefährdungsursache für die Wildkatze. Wie stark der Einfluss der Straßenverkehrsmortalität auf die Entwicklung einer Population ist, wurde bisher nicht untersucht. Die genaue Erfassung von Verkehrsopfern ermöglicht, Gefahrenschwerpunkte zu benennen, um effektive Artenschutzmaßnahmen herzuleiten. Diese Studie, die im Auftrag der Biosphärenreservatsverwaltung Karstlandschaft Südharz erstellt wurde, fokussiert auf die Ermittlung von Verkehrsstrecken mit erhöhter Mortalität und Unfallschwerpunkten. Im Folgenden werden Methoden und Ergebnisse vorgestellt sowie Handlungsempfehlungen für den Wildkatzenschutz formuliert

Three study decades on irrigation performance and salt concentrations and loads in the irrigation return flows of La Violada irrigation district (Spain)

30 Pags., 3 Tabls., 9 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/01678809Irrigation district salt balances identify the main sources and sinks of salts and quantify salt loads in irrigation return flows. Salt balances were performed in La Violada Irrigation District during the 80s (1982–1984), 90s (1995–1998) and 00s (2006–2008) decades. Total Dissolved Solids (TDS) and loads in irrigation return flows were related with changes in irrigation performance and infrastructures during these decades. TDS increased linearly to increases in Irrigation Consumptive Use Coefficient (ICUC) (P 66%, and decreased exponentially for values above and below these thresholds, respectively. Therefore, the key management strategy to reduce salt discharge to downstream areas is to decrease drainage volumes by improving irrigation management.This work was sponsored by the Spanish Ministry of Science and Education project AGL2006-11860/AGR, the European Regional Development Fund (FEDER) and the European Union project INCO CT-2005-015031.Peer reviewe

Significantly improved precision of cell migration analysis in time-lapse video microscopy through use of a fully automated tracking system

<p>Abstract</p> <p>Background</p> <p>Cell motility is a critical parameter in many physiological as well as pathophysiological processes. In time-lapse video microscopy, manual cell tracking remains the most common method of analyzing migratory behavior of cell populations. In addition to being labor-intensive, this method is susceptible to user-dependent errors regarding the selection of "representative" subsets of cells and manual determination of precise cell positions.</p> <p>Results</p> <p>We have quantitatively analyzed these error sources, demonstrating that manual cell tracking of pancreatic cancer cells lead to mis-calculation of migration rates of up to 410%. In order to provide for objective measurements of cell migration rates, we have employed multi-target tracking technologies commonly used in radar applications to develop fully automated cell identification and tracking system suitable for high throughput screening of video sequences of unstained living cells.</p> <p>Conclusion</p> <p>We demonstrate that our automatic multi target tracking system identifies cell objects, follows individual cells and computes migration rates with high precision, clearly outperforming manual procedures.</p

Изменение структурных характеристик асфальтенов тяжелого углеводородного сырья в термических процессах

AbstractObjectives. We attempted to evaluate the efficacy and tissue reaction of a new miniature interventional ductal occlusion device in neonatal pigs.Background. A variety of devices are used to close persistent ductus arteriosus (PDA) by interventional measures. Because of the size of these devices, they have not been applied to term or preterm neonates. Newborn piglets are comparable in size and fragility to human term and preterm neonates.Methods. Memory-shaped double-cone stainless steel coils were mounted on a titanium-nickel core wire. A snap-in mechanism attaches the coil to the delivery wire, allowing intravascular coil retrieval and repositioning. The system was placed through a 3F Teflon catheter. Two piglet models of PDA were used: 1) ductal patency maintained by stents (n = 6), and 2) ductal patency produced by angioplasty (n = 7) to avoid stent-coil interaction.Results. Placement of the coils within the PDA was possible in all piglets. Before final detachment, the coils were retrieved or repositioned, or both, up to eight times. In all but two piglets the ductus was closed within 1 h of the procedure. The coils were never dislocated and caused no infections or relevant aortic and pulmonary artery obstruction (95% confidence interval for missing complications [0 of 13] extends to 23%). Histologic and electron microscopic studies revealed endothelial coverage of the implants and histiocytic reaction but no local or systemic inflammation or erosion of the implant.Conclusions. The device was effective in experimental models of PDA. The information obtained warrants initial trials of the device in neonates

Agriculture intensity and landscape configuration influence the spatial use of wildcats across Europe

Land use intensification is increasing worldwide and affects wildlife movements, particularly of specialist carnivores. Resource availability and anthropogenic activities drive the extent and shape of home range size. Wildlife may respond to decreased resource availability under intensification scenarios by increasing their home ranges; however they may be less affected when inhabiting sustainable agricultural landscapes. We investigate whether agricultural practices and landscape configuration influence the spatial behaviour of wildcats, a medium-sized specialist carnivore inhabiting landscapes with different degrees of agricultural presence across Europe. We focus on the effect of the proportions of high impact and low impact agriculture, forest integrity and forest edge density on wildcat home range size. We found that wildcat home range increased along with the proportion of high impact agriculture and the forest integrity, whereas it decreased when forest edge density increased. Forest edge density buffered the detrimental effects caused by high impact agriculture. To enhance the long term conservation of wildcats in Europe it is crucial to protect the sustainable mosaic-structured landscapes and prevent its conversion to homogenous intensified agricultural landscapes.HRV is beneficiary of a PhD scholarship “Severo Ochoa” from the Regional Government of Principality of Asturias. JVLB was supported by a Ramón y Cajal research contract (RYC-2015-18932) from the Spanish Ministry of Economy, Industry and Competitiveness. F. Díaz-Ruiz was supported by a postdoctoral contract from the University of Málaga (I Plan Propio de Investigación y Transferencia, call 2020).Peer reviewe

Survival and cause-specific mortality of European wildcat (Felis silvestris) across Europe

Humans have transformed most landscapes across the globe, forcing other species to adapt in order to persist in increasingly anthropogenic landscapes. Wide-ranging solitary species, such as wild felids, struggle particularly in such landscapes. Conservation planning and management for their long-term persistence critically depends on understanding what determine survival and what are the main mortality risks. We carried out the first study on annual survival and cause-specific mortality of the European wildcat with a large and unique dataset of 211 tracked individuals from 22 study areas across Europe. Furthermore, we tested the effect of environmental and human disturbance variables on the survival probability. Our results show that mortalities were mainly human-caused, with roadkill and poaching representing 57% and 22% of the total annual mortality, respectively. The annual survival probability of wildcat was 0.92 (95% CI = 0.87–0.98) for females and 0.84 (95% CI = 0.75–0.94) for males. Road density strongly impacted wildcat annual survival, whereby an increase in the road density of motorways and primary roads by 1 km/km2 in wildcat home-ranges increased mortality risk ninefold. Low-traffic roads, such as secondary and tertiary roads, did not significantly affect wildcat's annual survival. Our results deliver key input parameters for population viability analyses, provide planning-relevant information to maintain subcritical road densities in key wildcat habitats, and identify conditions under which wildcat-proof fences and wildlife crossing structures should be installed to decrease wildcat mortality.This research was funded by: the German Federal Ministry of Transport and Digital Infrastructure (BMVI) as part of the mFund project “WilDa—Dynamic Wildlife–Vehicle Collision warning, using heterogeneous traffic, accident and environmental data as well as big data concepts” grant number 19F2014B; the Deutscher Akademischer Austauschdienst (DAAD) Research Grants, Short-Term Grants, 2020 (57507441); the Deutsche Wildtier Stiftung (DeWiSt). The data from Cabañeros National Park were collected in the frame of the project OAPN 352/2011 funded by Organismo Autónomo Parques Nacionales. MM was supported by a research contract Ramón y Cajal from the MINECO (RYC-2015-19231). FDR was supported by a postdoctoral contract funded by the University of Málaga through the grants program “Ayudas para la Incorporación de Doctores del I Plan Propio de Investigación de la Universidad de Málaga (Call 2019)”. PM was supported by UIDB/50027/2020 with funding from FCT/MCTES through national funds.Peer reviewe

A common statement on anthropogenic hybridization of the European wildcat (Felis silvestris)

Preserving natural genetic diversity and ecological function of wild species is a central goal in conservation biology. As such, anthropogenic hybridization is considered a threat to wild populations, as it can lead to changes in the genetic makeup of wild species and even to the extinction of wild genomes. In European wildcats, the genetic and ecological impacts of gene flow from domestic cats are mostly unknown at the species scale. However, in small and isolated populations, it is known to include genetic swamping of wild genomes. In this context, it is crucial to better understand the dynamics of hybridization across the species range, to inform and implement management measures that maintain the genetic diversity and integrity of the European wildcat. In the present paper, we aim to provide an overview of the current scientific understanding of anthropogenic hybridization in European wildcats, to clarify important aspects regarding the evaluation of hybridization given the available methodologies, and to propose guidelines for management and research priorities

Im Fokus der Wissenschaft : die Wildkatze im Unterharz

Im südöstlichen Teil des Harzes steht die Europäische Wildkatze (Felis s. silvestris) (Abb. 1) bereits seit den 1950er Jahren im Mittelpunkt des wissenschaftlichen Artenschutzes. Rudolf Piechocki (1919–2000) beruft sich in seiner 1990 erschienenen und heute als Standardwerk geltenden Monografie der Wildkatze immer wieder auf umfangreiche Datensammlungen aus dem östlichen Gebiet der Harzpopulation (Piechocki 1990). Einen Großteil der ökologischen Erkenntnisse über die Wildkatze gewann er im Südharz zusammen mit dem engagierten Artenschützer Harro Möller (1923–2001) aus Sangerhausen