Influence of the vegetation structure on the nest-site selection of birds of prey in the March floodplain forests, Lower Austria

Zwischen Januar und Juli 2008 wurden im March-Auwald zwischen Hohenau und Drösing im niederösterreichischen Bezirk Gänserndorf (19,7 km2) systematisch Greifvogelhorste kartiert, und auf Besetzung und Bruterfolg kontrolliert. Im weitgehend geschlossenen Waldgebiet sind zwei unterschiedliche Forstwirtschaftsformen vorrangig. Der nördliche Teil wird als Hochwald (960 ha) geführt, der südliche Teil als Mittel- und Niederwald (1010 ha). Analysen zur Waldstruktur rund um jeden Horstplatz (Mikrohabitat, r=15 m, 706,5 m2), sowie zum Anteil verschiedener Biotoptypen im Kernbereich der Greifvogelreviere (Makrohabitat, r=250 m, 19,6 ha) geben Aufschluss, welche Faktoren die Verbreitung der Greifvögel in den March-Auen beeinflussen. Um einen repräsentativen Querschnitt des vorhandenen Strukturangebots zu erhalten, wurden die Erhebungen in gleicher Art auf 50 zufällig bestimmten Flächen wiederholt. Die erhobenen Daten zur Habitatwahl wurden in einem geographischen Informationssystem ausgewertet. Insgesamt wurden 167 Horste kartiert, davon waren 57 von Greifvögeln besetzt. Die häufigste Art ist der Mäusebussard (Buteo buteo) mit 34 besetzten Horsten, gefolgt von der Rohrweihe (Circus aeroginosus) mit 5-6 Brutpaaren. Der Rotmilanbestand (Milvus milvus) von 3 Brutpaaren ist von nationaler Bedeutung. Schwarzmilan (Milvus migrans), Wespenbussard (Pernis apivorus) und Habicht (Accipiter gentilis) sind mit je 3 Brutpaaren, Turmfalke (Falco tinnunculus) und Baumfalke (Falco subbuteo) mit je 2 Brutpaaren vertreten. Seit 2002 brütet auch ein Seeadlerpaar (Haliaeetus albicilla) erfolgreich im Untersuchungsgebiet. Zusätzlich brüten Sperber (Accipiter nisus), Sakerfalke (Falco cherrug) und Kaiseradler (Aquila heliaca) in den umliegenden Flächen. Die Greifvogelbestände sind seit den 1990er Jahren weitgehend stabil. Allein beim Mäusebussard ist eine Bestandszunahme zu verzeichnen, die auf natürliche Schwankungen entsprechend der Mäusegradation und auf eine Entdynamisierung der Au zurückzuführen ist. Die vorgefundenen Siedlungsdichten der Greifvögel an der March sind auch in einem mitteleuropäischen Vergleich als hoch einzustufen. Die Habitatanalyse hat gezeigt, dass Greifvögel Stieleichenüberhälter und zusammenhängende, alte Pappelkulturen als Horstbäume bevorzugen. Diese Baumarten finden sich im Mittelwald häufiger als im Hochwald. Auch sind im Mittelwald mehr Großhorste zu finden, die wertvoll für Seeadler und Kaiseradler, sowie den Schwarzstorch sind. Darüber hinaus bevorzugen Greifvögel strukturierte Altholzbestände mit einer ausgeprägten vertikalen Schichtung und einem hohen Totholzanteil. Diese Strukturen deuten auf einen geringen forstlichen Nutzen und dadurch eine geringe menschliche Störung der Nistplätze hin. Die genannten Kriterien erfüllen insbesondere eingerichtete Horstschutzgebiete, die frei von forstlicher Nutzung sind. Die Ausdehnung der Altholzbestände, die Reduzierung von Störungen durch den Menschen sowie die Dynamisierung der Au durch Revitalisierungsprojekte sind wichtige Schritte für einen langfristigen Erhalt der vielfältigen Greifvogelfauna der March-Auen.Between Austria, Slovakia and the Czech Republic, were studied in 2008. The study area (19.7 km2) had not been explored by ornithologists until the 1990s due to the considerable flood dynamics and the subsequent limited accessibility. The present field study was performed between January and July 2008 between Hohenau and Drösing (Lower Austria), consisting of two reference areas of comparable size but with different cultivation techniques, i.e. the high forest cultivation in the North (960 ha) and the middle forest cultivation in the South (1010 ha). Additionally, the field study was conducted to explore the influence of the vegetation structure around the nesting site (microhabitat, r=15 m, 706.5 m2) and the landscape characteristics (macrohabitat, r=250 m, 19.6 ha) on the habitat choices of birds of prey. To get a representative sample for comparison, the same data were collected at 50 randomly selected sites. Aeries were mapped along transects between 50 m intervals, and 167 were found in total. 57 out of 167 aeries were occupied by birds of prey. In total, nine breeding raptor species were recorded. The most abundant species was the Common Buzzard (Buteo buteo), occupying 34 aeries, followed by the Marsh Harrier (Circus aeroginosus) with five or six pairs. The Red Kite (Milvus milvus) population, with a quantity of three pairs was remarkable on a national scale. The Black Kite (Milvus migrans) (three pairs), the Honey Buzzard (Pernis apivorus) (three pairs), the Goshawk (Accipiter gentilis) (three pairs), the Kestrel (Falco tinnunculus) (two pairs) and the Hobby (Falco subbuteo) (two pairs) also bred in the study area. Since 2002 the White-tailed Eagle (Haliaeetus albicilla) has bred successfully in the floodplains. The Sparrowhawk (Accipiter nisus), the Saker Falcon (Falco cherrug) and the Imperial Eagle (Aquila heliaca) were not found as breeders in the study area, but were known to breed nearby. The results indicated a population growth of the Common Buzzard, whereas the density of other predatory birds has been steady for the last 15 years. The density is high compared to other places in central Europe, including the Danube floodplains in Austria. Besides, the density seems to be independent from the type of cultivation. The data concerning the habitat structure were analyzed in a Geographic Information System (GIS) and indicate the March flood-plain forests as very attractive for raptors. The investigation area offers a varied and structured landscape with abundant waterbodies and meadows. Predatory birds prefer old growth trees, particularly oaks (Quercus sp.) and poplars (Populus sp.) for nesting. These types of trees are numerous in middle forest cultivation. Additionally, a higher number of older aeries can be found there compared to high forest cultivations. Birds of prey prefer a distinctive forest structure with plenty of deadwood, far away from paths or protected by dense shrub and undergrowth. Therefore, the conservation of mature forests, the reduction of human disturbance and the reactivation of the flood dynamics could have a positive effect on the raptor population in the long term

Comparative morphology of the mouthparts of the megadiverse South African monkey beetles (Scarabaeidae: Hopliini): feeding adaptations and guild structure

Although anthophilous Coleoptera are regarded to be unspecialised flower-visiting insects, monkey beetles (Scarabaeidae: Hopliini) represent one of the most important groups of pollinating insects in South Africa’s floristic hotspot of the Greater Cape Region. South African monkey beetles are known to feed on floral tissue; however, some species seem to specialise on pollen and/or nectar. The present study examined the mouthpart morphology and gut content of various hopliine species to draw conclusions on their feeding preferences. According to the specialisations of their mouthparts, the investigated species were classified into different feeding groups. Adaptations to pollen-feeding included a well-developed, toothed molar and a lobe-like, setose lacinia mobilis on the mandible as well as curled hairs or sclerotized teeth on the galea of the maxillae. Furthermore, elongated mouthparts were interpreted as adaptations for nectar feeding. Floral- and folial-tissue feeding species showed sclerotized teeth on the maxilla, but the lacinia was mostly found to be reduced to a sclerotized ledge. While species could clearly be identified as floral or folial tissue feeding, several species showed intermediate traits suggesting both pollen and nectar feeding adaptations. Mismatches found between mouthpart morphology and previously reported flower visiting behaviours across different genera and species requires alternative explanations, not necessarily associated with feeding preferences. Although detailed examinations of the mouthparts allowed conclusions about the feeding preference and flower-visiting behaviour, additional morphological and behavioural investigations, combined with greater taxon sampling and phylogenetic data, are still necessary to fully understand hopliine host plant relationships, related to monkey beetle diversity

Pollen Processing Behavior of Heliconius Butterflies: A Derived Grooming Behavior

Pollen feeding behaviors Heliconius and Laparus (Lepidoptera: Nymphalidae) represent a key innovation that has shaped other life history traits of these neotropical butterflies. Although all flower visiting Lepidoptera regularly come in contact with pollen, only Heliconius and Laparus butterflies actively collect pollen with the proboscis and subsequently take up nutrients from the pollen grains. This study focused on the behavior of pollen processing and compared the movement patterns with proboscis grooming behavior in various nymphalid butterflies using video analysis. The proboscis movements of pollen processing behavior consisted of a lengthy series of repeated coiling and uncoiling movements in a loosely coiled proboscis position combined with up and down movements and the release of saliva. The proboscis-grooming behavior was triggered by contamination of the proboscis in both pollen feeding and non-pollen feeding nymphalid butterflies. Proboscis grooming movements included interrupted series of coiling and uncoiling movements, characteristic sideways movements, proboscis lifting, and occasionally full extension of the proboscis. Discharge of saliva was more pronounced in pollen feeding species than in non-pollen feeding butterfly species. We conclude that the pollen processing behavior of Heliconius and Laparus is a modified proboscis grooming behavior that originally served to clean the proboscis after contamination with particles

Time management and nectar flow: flower handling and suction feeding in long-proboscid flies (Nemestrinidae: Prosoeca)

A well-developed suction pump in the head represents an important adaptation for nectar-feeding insects, such as Hymenoptera, Lepidoptera and Diptera. This pumping organ creates a pressure gradient along the proboscis, which is responsible for nectar uptake. The extremely elongated proboscis of the genus Prosoeca (Nemestrinidae) evolved as an adaptation to feeding from long, tubular flowers. According to the functional constraint hypothesis, nectar uptake through a disproportionately elongated, straw-like proboscis increases flower handling time and consequently lowers the energy intake rate. Due to the conspicuous length variation of the proboscis of Prosoeca, individuals with longer proboscides are hypothesised to have longer handling times. To test this hypothesis, we used field video analyses of flower-visiting behaviour, detailed examinations of the suction pump morphology and correlations of proboscis length with body length and suction pump dimensions. Using a biomechanical framework described for nectar-feeding Lepidoptera in relation to proboscis length and suction pump musculature, we describe and contrast the system in long-proboscid flies. Flies with longer proboscides spent significantly more time drinking from flowers. In addition, proboscis length and body length showed a positive allometric relationship. Furthermore, adaptations of the suction pump included an allometric relationship between proboscis length and suction pump muscle volume and a combination of two pumping organs. Overall, the study gives detailed insight into the adaptations required for long-proboscid nectar feeding, and comparisons with other nectar-sucking insects allow further considerations of the evolution of the suction pump in insects with sucking mouthparts. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00114-013-1114-6) contains supplementary material, which is available to authorized users

Effect of anisotropy and destructuration on behavior of Haarajoki test embankment

This paper investigates the influence of anisotropy and destructuration on the behavior of Haarajoki test embankment, which was built by the Finnish National Road Administration as a noise barrier in 1997 on a soft clay deposit. Half of the embankment is constructed on an area improved with prefabricated vertical drains, while the other half is constructed on the natural deposit without any ground improvement. The construction and consolidation of the embankment is analyzed with the finite-element method using three different constitutive models to represent the soft clay. Two recently proposed constitutive models, namely S-CLAY1 which accounts for initial and plastic strain induced anisotropy, and its extension, called S-CLAY1S which accounts, additionally, for interparticle bonding and degradation of bonds, were used in the analysis. For comparison, the problem is also analyzed with the isotropic modified cam clay model. The results of the numerical analyses are compared with the field measurements. The simulations reveal the influence that anisotropy and destructuration have on the behavior of an embankment on soft clay

The allometry of proboscis length in Melittidae (Hymenoptera: Apoidae) and an estimate of their foraging distance using museum collections

An appreciation of body size allometry is central for understanding insect pollination ecology. A recent model utilises allometric coefficients for five of the seven extant bee families (Apoidea: Anthophila) to include crucial but difficult-to-measure traits, such as proboscis length, in ecological and evolutionary studies. Melittidae were not included although they are important pollinators in South Africa where they comprise an especially rich and morphologically diverse fauna. We measured intertegular distance (correlated with body size) and proboscis length of 179 specimens of 11 species from three genera of Melittidae. With the inclusion of Melittidae, we tested the between family differences in the allometric scaling coefficients. AIC model selection was used to establish which factors provide the best estimate of proboscis length. We explored a hypothesis that has been proposed in the literature, but which has not been tested, whereby body and range sizes of bees are correlated with rainfall regions. We tested this by using body size measurements of 2109 museum specimens from 56 species of Melittidae and applied the model coefficients to estimate proboscis length and foraging distance. Our results show that with the addition of Melittidae, we retained the overall pattern of significant differences in the scaling coefficient among Apoidea, with our model explaining 98% of the variance in species-level means for proboscis length. When testing the relationship between body size and rainfall region we found no relationship for South African Melittidae. Overall, this study has added allometric scaling coefficients for an important bee family and shown the applicability of using these coefficients when linked with museum specimens to test ecological hypothesi

Towards Symbolic Model-Based Mutation Testing: Combining Reachability and Refinement Checking

Model-based mutation testing uses altered test models to derive test cases that are able to reveal whether a modelled fault has been implemented. This requires conformance checking between the original and the mutated model. This paper presents an approach for symbolic conformance checking of action systems, which are well-suited to specify reactive systems. We also consider nondeterminism in our models. Hence, we do not check for equivalence, but for refinement. We encode the transition relation as well as the conformance relation as a constraint satisfaction problem and use a constraint solver in our reachability and refinement checking algorithms. Explicit conformance checking techniques often face state space explosion. First experimental evaluations show that our approach has potential to outperform explicit conformance checkers.Comment: In Proceedings MBT 2012, arXiv:1202.582

Observation of three-photon Greenberger-Horne-Zeilinger entanglement

We present the experimental observation of polarization entanglement for three spatially separated photons. Such states of more than two entangled particles, known as GHZ states, play a crucial role in fundamental tests of quantum mechanics versus local realism and in many quantum information and quantum computation schemes. Our experimental arrangement is such that we start with two pairs of entangled photons and register one photon in a way that any information as to which pair it belongs to is erased. The registered events at the detectors for the remaining three photons then exhibit the desired GHZ correlations.Comment: Revtex, 4 pages, uses floats, epsfi

Relationship between molecular pathogen detection and clinical disease in febrile children across Europe: a multicentre, prospective observational study

BackgroundThe PERFORM study aimed to understand causes of febrile childhood illness by comparing molecular pathogen detection with current clinical practice.MethodsFebrile children and controls were recruited on presentation to hospital in 9 European countries 2016-2020. Each child was assigned a standardized diagnostic category based on retrospective review of local clinical and microbiological data. Subsequently, centralised molecular tests (CMTs) for 19 respiratory and 27 blood pathogens were performed.FindingsOf 4611 febrile children, 643 (14%) were classified as definite bacterial infection (DB), 491 (11%) as definite viral infection (DV), and 3477 (75%) had uncertain aetiology. 1061 controls without infection were recruited. CMTs detected blood bacteria more frequently in DB than DV cases for N. meningitidis (OR: 3.37, 95% CI: 1.92-5.99), S. pneumoniae (OR: 3.89, 95% CI: 2.07-7.59), Group A streptococcus (OR 2.73, 95% CI 1.13-6.09) and E. coli (OR 2.7, 95% CI 1.02-6.71). Respiratory viruses were more common in febrile children than controls, but only influenza A (OR 0.24, 95% CI 0.11-0.46), influenza B (OR 0.12, 95% CI 0.02-0.37) and RSV (OR 0.16, 95% CI: 0.06-0.36) were less common in DB than DV cases. Of 16 blood viruses, enterovirus (OR 0.43, 95% CI 0.23-0.72) and EBV (OR 0.71, 95% CI 0.56-0.90) were detected less often in DB than DV cases. Combined local diagnostics and CMTs respectively detected blood viruses and respiratory viruses in 360 (56%) and 161 (25%) of DB cases, and virus detection ruled-out bacterial infection poorly, with predictive values of 0.64 and 0.68 respectively.InterpretationMost febrile children cannot be conclusively defined as having bacterial or viral infection when molecular tests supplement conventional approaches. Viruses are detected in most patients with bacterial infections, and the clinical value of individual pathogen detection in determining treatment is low. New approaches are needed to help determine which febrile children require antibiotics.FundingEU Horizon 2020 grant 668303