Das Rebhuhnschutzprojekt im Landkreis Göttingen - Blühstreifenmanagement für das Rebhuhn

Auch im Landkreis Göttingen ist das Rebhuhn in den letzten Jahrzehnten stark zurückgegangen. Das Rebhuhnschutzprojekt im Landkreis Göttingen hat das Ziel, den Rebhuhnbestand langfristig anzuheben, um damit das Risiko des lokalen Aussterbens zu reduzieren. Ca. 300-400 Rebhuhnpaare leben im Landkreis. Seit 2005 werden rebhuhngerecht bewirtschaftete Blühstreifen angebaut, 2007 waren ca. 1.000 solcher Flächen etabliert, insgesamt 540 Hektar. Alljährliche Zählungen des Rebhuhnbestandes auf 90 km² haben in den Jahren nach 2007 einen deutlichen Anstieg der Rebhuhnzahlen nachweisen können. 2007 war der Großteil der Blühstreifen eingerichtet worden. Auch die Populationseinbrüche nach den schneereichen Wintern 2009/10 und 2010/11 konnten schnell aufgeholt werden. Ab 2012 lief ein Teil der Blühstreifenverträge aus und die Rebhuhnpopulation konnte nicht wieder den vorübergehenden Höchststand von 2009 erreichen. Lokal, bei einem Blühstreifenanteil von ca. 7 % der Ackerfläche, hat sich der Rebhuhnbestand innerhalb von drei Jahren verzehnfacht. In einer Telemetriestudie zur Habitatnutzung, Mortalität und zum Bruterfolg wurden 139 Rebhühner besendert und ihre Lebensläufe verfolgt. Die Blühstreifen werden überproportional genutzt und sind mit einem Viertel aller Brutplätze ein bedeutender Bestandteil des Lebensraumes geworden. Die Überlebensrate von Nestern in den breiten Blühstreifen und –flächen ist doppelt so hoch wie die in Hecken und Feldrainen. Fast alle Verluste von Rebhühnern sind der Prädation zuzuschreiben. Besonders schwer wiegt die Prädation der Hennen auf dem Nest, die gleichzeitig die wichtigste Ursache für Nestverluste ist. Die winterlichen Verluste sind nur bei Schneelage hoch. Wichtigster Prädator ist der Fuchs. Trotz der hohen Prädationsraten wird im Projekt kein Einfluss auf die Bejagung genommen, der Focus liegt ausschließlich auf den Lebensraumaufwertungen. Schwellenwerte des Anteils von Blühstreifen an der landwirtschaftlich genutzten Fläche werden diskutiert. Eine stabile Verdopplung des Rebhuhnbestandes würde ca. die dreifache Menge an Blühstreifen im Landkreis erfordern, sofern diese gezielt platziert werden.Stichwörter: Rebhuhn, Perdix perdix, Agrarumweltmaßnahme, Blühstreifen, PrädationThe partridge conservation project at the district of Göttingen - management of fl ower stripsAbstractThe partridge declined at the district of Göttingen seriously. The partridge conservation project of the Göttingen district tries to minimize the local extinction risk, by raising the population size. 300 – 400 pairs of partridges still exist. Flower strips adapted to the needs of partridges are introduced since 2005; in 2007 about 1.000 flower strips have been established (540 hectare). Our partridge count scheme detects an increase in numbers in the two following years. After two winters with long periods of high snow cover the population decreased, but recovered quickly in 2011. In 2012 many flower strip contracts ended and the population did not reach the level of 2009 again. Locally the flower strips covered about 7 % of the agricultural area. There the partridge numbers increased tenfold within 3 years. We studied habitat use, mortality and breeding success of partridges by radiotracking 139 partridges during 2009-2013. They used flower strips much more than expected. One quarter of nests was located in flower strips. Survival rate of nests in the broad flower strips and fl ower fields was 50 %, in hedgerows and other linear structures only 25 % due to a different predation rate of breeding hens. Winter losses were only high during periods of snow cover. Losses are mainly attributed to foxes. We do not take any infl uence on predation control. We discuss thresholds for the amount of area covered by flower strips which is needed to raise the partridge population. To double population size 1500 hectares are necessary, if placed selectively.Keywords: Grey partridge, Perdix perdix, agri-environment scheme, flower strip, predatio

A universal strategy for high-yield production of soluble and functional clostridial collagenases in E. coli

Clostridial collagenases are foe and friend: on the one hand, these enzymes enable host infiltration and colonization by pathogenic clostridia, and on the other hand, they are valuable biotechnological tools due to their capacity to degrade various types of collagen and gelatine. However, the demand for high-grade preparations exceeds supply due to their pathogenic origin and the intricate purification of homogeneous isoforms. We present the establishment of an Escherichia coli expression system for a variety of constructs of collagenase G (ColG) and H (ColH) from Clostridium histolyticum and collagenase T (ColT) from Clostridium tetani, mimicking the isoforms in vivo. Based on a setup of five different expression strains and two expression vectors, 12 different constructs were expressed, and a flexible purification platform was established, consisting of various orthogonal chromatography steps adaptable to the individual needs of the respective variant. This fast, cost-effective, and easy-to-establish platform enabled us to obtain at least 10 mg of highly pure mono-isoformic protein per liter of culture, ideally suited for numerous sophisticated downstream applications. This production and purification platform paves the way for systematic screenings of recombinant collagenases to enlighten the biochemical function and to identify key residues and motifs in collagenolysis

Prediction of second neurological attack in patients with clinically isolated syndrome using support vector machines

The aim of this study is to predict the conversion from clinically isolated syndrome to clinically definite multiple sclerosis using support vector machines. The two groups of converters and non-converters are classified using features that were calculated from baseline data of 73 patients. The data consists of standard magnetic resonance images, binary lesion masks, and clinical and demographic information. 15 features were calculated and all combinations of them were iteratively tested for their predictive capacity using polynomial kernels and radial basis functions with leave-one-out cross-validation. The accuracy of this prediction is up to 86.4% with a sensitivity and specificity in the same range indicating that this is a feasible approach for the prediction of a second clinical attack in patients with clinically isolated syndromes, and that the chosen features are appropriate. The two features gender and location of onset lesions have been used in all feature combinations leading to a high accuracy suggesting that they are highly predictive. However, it is necessary to add supporting features to maximise the accuracy. © 2013 IEEE

An individual based model of the impact of suboptimal habitat on survival of the grey bush cricket, Platycleis albopunctata (Orthoptera: Tettigoniidae)

We developed an individual based model that investigates the importance of suboptimal habitats for the survival of the grey bush cricket Platycleis albopunctata living in a core habitat. Our model consists of two submodels. The first describes the demographic growth of the cricket known to mainly depend on temperature. The second introduces a simple heterogeneous habitat that consists of two areas of variable size and different suitability for reproduction. An optimal habitat is surrounded by a suboptimal habitat and both together are located within an unsuitable area. Applying Monte Carlo simulations we demonstrate that the extinction probability of a bush cricket population is significantly lower in an optimal habitat with a surrounding suboptimal habitat than without. Even small suboptimal habitats are sufficient to significantly reduce the extinction risk of the core population. For a bush cricket population living in a heterogeneous habitat mean minimum viable population estimates range from 13 000 to 15 000 adults, whereas 30 000 adults are required for a population living in an optimal habitat without a surrounding suboptimal habitat. Thus, the presence of a suboptimal habitat can reduce minimum viable population by 50%. For any species, our model predicts that the type of dispersal between optimal and suboptimal habitat and the type of habitat selection determine whether suboptimal habitat is useful or detrimental for species persistence

Camera trap data suggest uneven predation risk across vegetation types in a mixed farmland landscape

Abstract Ground‐nesting farmland birds such as the grey partridge (Perdix perdix) have been rapidly declining due to a combination of habitat loss, food shortage, and predation. Predator activity is the least understood factor, especially its modulation by landscape composition and complexity. An important question is whether agri‐environment schemes such as flower strips are potentially useful for reducing predation risk, for example, from red fox (Vulpes vulpes). We employed 120 camera traps for two summers in an agricultural landscape in Central Germany to record predator activity (i.e., the number of predator captures) as a proxy for predation risk and used generalized linear mixed models (GLMMs) to investigate how the surrounding landscape affects predator activity in different vegetation types (flower strips, hedges, field margins, winter cereal, and rapeseed fields). Additionally, we used 48 cameras to study the distribution of predator captures within flower strips. Vegetation type was the most important factor determining the number of predator captures and capture rates in flower strips were lower than in hedges or field margins. Red fox capture rates were the highest of all predators in every vegetation type, confirming their importance as a predator for ground‐nesting birds. The number of fox captures increased with woodland area and decreased with structural richness and distance to settlements. In flower strips, capture rates in the center were approximately 9 times lower than at the edge. We conclude that the optimal landscape for ground‐nesting farmland birds seems to be open farmland with broad extensive vegetation elements and a high structural richness. Broad flower blocks provide valuable, comparatively safe nesting habitats, and the predation risk can further be minimized by placing them away from woods and settlements. Our results suggest that adequate landscape management may reduce predation pressure

Assessing in-field pesticide effects under European regulation and its implications for biodiversity: a workshop report

Abstract Background Biodiversity loss is particularly pronounced in agroecosystems. Agricultural fields cover about one-third of the European Union and are crucial habitats for many species. At the same time, agricultural fields receive the highest pesticide input in European landscapes. Non-target species, including plants and arthropods, closely related to targeted pests, are directly affected by pesticides. Direct effects on these lower trophic levels cascade through the food web, resulting in indirect effects via the loss of food and habitat for subsequent trophic levels. The overarching goals of the European pesticide legislation require governments to sufficiently consider direct and indirect effects on plants and arthropods when authorising pesticides. This publication provides an overview of a workshop's findings in 2023 on whether the current pesticide risk assessment adequately addresses these requirements. Results Effects due to in-field exposure to pesticides are currently not assessed for plants and inadequately assessed for arthropods, resulting in an impairment of the food web support and biodiversity. Deficiencies lie within the risk assessment, as defined in the terrestrial guidance document from 2002. To overcome this problem, we introduce a two-step assessment method feasible for risk assessors, that is to determine (i) whether a pesticide product might have severe impacts on plants or arthropods and (ii) whether these effects extend to a broad taxonomic spectrum. When each step is fulfilled, it can be concluded that the in-field exposure of the pesticide use under assessment could lead to unacceptable direct effects on non-target species in-field and thus subsequent indirect effects on the food web. While our primary focus is to improve risk assessment methodologies, it is crucial to note that risk mitigation measures, such as conservation headlands, exist in cases where risks from in-field exposure have been identified. Conclusions We advocate that direct and indirect effects caused by in-field exposure to pesticides need to be adequately included in the risk assessment and risk management as soon as possible. To achieve this, we provide recommendations for the authorities including an evaluation method. Implementing this method would address a major deficiency in the current in-field pesticide risk assessment and ensure better protection of biodiversity