Successfully releasing jackdaws, Corvus monedula: spatial dispersion and the fusion of social groups

In der vorliegenden Studie untersuchten wir eine Auswilderung von in einer Voliere gehaltenen Dohlen (Corvus monedula), die in einer erfolgreichen Etablierung einer Wildkolonie mündete. Die Auswilderung erfolgte in zwei Stufen in den Jahren 2007 und 2009. Im ersten Projektjahr lag der Fokus unserer Untersuchung auf der räumlichen Ausbreitung der ausgewilderten Individuen, die zunächst nur allmählich, dann jedoch fast sprunghaft erfolgte. Mit der räumlichen Ausbreitung der Individuen auf andere als die in unmittelbarer Nähe zur Voliere gelegenen Bereiche war auch eine veränderte funktionelle Nutzung des Raumes verbunden, in der vor allem das Zentrum der Aktivitäten der Vögel verlagert wurde. Das zweite Projektjahr war der Untersuchung gewidmet, wie sich eine neuerlich ausgewilderte Dohlengruppe mit der bereits bestehenden Wildkolonie zu einer sozialen Gruppe zusammenschließen würde. In diesem Prozess benutzten die beiden Kolonien unterschiedliche Strategien der Annäherung. Während Individuen der Wildkolonie mit den hinzugekommenen Individuen häufiger in aggressiver Weise Kontakt aufnahmen, zeigten umgekehrt die neu ausgewilderten Individuen gegenüber Individuen der Wildkolonie vor allem soziopositives Verhalten. Obwohl die beiden Kolonien nach nur rund zwei Wochen räumlich als eine Kolonie betrachtet werden durften, zeigen unsere Ergebnisse, dass der soziale Zusammenschluss erst nach etwa zwei Monaten erreicht war. Unsere Studie zeigt auch Kontextfaktoren bzw. Faktoren der Biologie von Dohlen auf, die für eine erfolgreiche Auswilderung von besonderer Bedeutung sind: das visuelle Kennenlernen der neuen Umgebung, die Dynamik von Dohlenkolonien als offene Gruppen, in denen Abwanderungen und Neuzugänge ein häufiges Phänomen sind und für Auswilderungszwecke genutzt werden können und die Wichtigkeit einer etablierten Dominanzhierarchie in der dominante Individuen Führungsrollen übernehmen und Artgenossen diesen folgen können.The focus of the present study was a release project on jackdaws (Corvus monedula) which was carried out in two steps in 2007 and 2009. In 2007 we focused on the spatial dispersion of individuals which started gradually but then turned into a stepwise increase. A change in the functional use of space was associated with the birds’ spatial dispersion into areas other than those immediately surrounding the aviary in which especially the centre of the birds’ activities was relocated. 2009 focused on the analysis of the process how a newly released group of jackdaws and the already existing wild colony of birds would unite into a single social group. In this process both colonies used different strategies: in contrast to the individuals of the wild colony that mainly approached the newly released individuals in an aggressive manner, the latter initiated more sociopositive interactions towards the former. Although after two weeks the two colonies could be considered as one when referring to their spatial cohesiveness, our results show that their social cohesiveness was achieved only after about two months. Furthermore, our study indicates which factors of the context and the biology of jackdaws, respectively, may be especially important for a successful release in these birds: visual acquaintance with the new environment, social dynamics of jackdaw colonies that represent free entry groups in which emigration and immigration are frequent phenomena and can be used for releasing purposes, and the importance of an established dominance hierarchy due to which dominant individuals can take the lead while subdominant conspecifics may follow them

Social relations affect social learning in ravens, Corvus corax, and jackdaws, Corvus monedula

Ziel meiner Dissertation war es, mittels eines vergleichenden Ansatzes, den Einfluss sozialer Beziehungen auf soziales Lernen zu untersuchen. Ich arbeitete mit zwei phylogenetisch nahe verwandten Arten, Kolkraben (Corvus corax) und Turmdohlen (Corvus monedula). Dieser Arbeit lag die Hypothese zugrunde, dass Toleranz und eine enge soziale Verbindung zwischen Individuen deren soziale Lernleistung begünstigt. Die besten Voraussetzungen für den Austausch an Information bestünden zwischen Individuen, die zur selben Zeit am selben Ort sind, was in nicht-egalitär strukturierten Gruppen nur zwischen bestimmten Individuen der Fall wäre. Daher seien manche Demonstratoren für bestimmte Artgenossen einflussreicher als andere in Hinblick auf gerichtetes soziales Lernen, welches darüber hinaus der wahrscheinlichste Mechanismus sei mittels dessen sich Information innerhalb einer Gruppe verbreite. Raben- und Dohlengruppen sind nicht-egalitär strukturiert, wodurch die Wahrscheinlichkeit, dass gerichtetes soziales Lernen auftritt, erhöht wird. Zunächst analysierte ich die sozialen Beziehungen zwischen den unter Einjährigen unserer beiden handaufgezogenen und in Volieren gehaltenen Gruppen von Raben und Dohlen. Die Ergebnisse zeigten, dass Jungvögel beider Arten enge soziale Beziehungen mit ihren Nestgeschwistern unterhalten, also jenen Artgenossen mit denen sie gemeinsam in einem Nest handaufgezogen wurden. Detailliertere Analysen der Beziehungen zwischen Dohlen ergaben, dass diese als wertvolle Beziehungen bezeichnet werden können, die sich durch enge räumliche Nähe, gegenseitiges Füttern, Putzen und Berühren, Unterstützung bei agonistischen Interaktionen und gemeinsames Objektspiel charakterisieren lassen. Daher wurden die Vögel in darauffolgenden „stimulus enhancement“ Lernexperimenten in Dyaden getestet, deren Individuen entweder enge (Nestgeschwister) oder nicht enge (Nicht-Nestgeschwister) Beziehungen zueinander pflegen. Die Ergebnisse der Jungraben unterstützten die oben genannte Hypothese insofern als sie besser von ihren Nestgeschwistern als von ihren Nicht-Nestgeschwistern lernten. Gestützt werden diese Ergebnisse ebenso von der Nahrungsökologie von Raben. Raben verstecken ihre Nahrung zu einem großen Teil und die innerartliche Konkurrenz an monopolisierbaren Nahrungsressourcen ist hoch. Um Zugang zu Nahrung zu erlangen und um adäquate Strategien zum Schutz ihrer Verstecke zu entwickeln benötigen Raben Erfahrungen rund um ihre eigenen Verstecke mit potentiellen Versteck-Plünderern. Diese potentiellen Plünderer sind mit großer Wahrscheinlichkeit Individuen mit denen sie viel Zeit in unmittelbarer Umgebung verbringen, also ihre Nestgeschwister, wodurch der Wert der Nestgeschwister als relevante Informationsquelle erhöht wird, was gerichtetes soziales Lernen von denselben zweckmäßig erscheinen lässt. Im Gegensatz dazu lernten Dohlen in meinen Versuchen besser von Individuen, mit denen sie keine engen Beziehungen pflegen, also von Nicht-Nestgeschwistern und Nicht-Paarpartnern. Anders als Raben ernähren sich Dohlen vor allem von verstreuten Nahrungsressourcen, weshalb sie vor allem räumliche Information darüber benötigen wo die Nahrungssuche lohnt. Auch sie verbringen die meiste Zeit in unmittelbarer Umgebung zu jenen Individuen, mit denen sie enge Beziehungen pflegen (Nestgeschwister und Paarpartner), wodurch die Wahrscheinlichkeit erhöht wird, dass diese Individuen ähnliche Informationen aus ihrer Umwelt beziehen als sie selbst. Räumlich weiter entfernte Individuen jedoch, also jene, zu denen keine engen Beziehungen unterhalten werden, könnten bei der Nahrungssuche andere Erfahrungen machen und daher unterschiedliche und/oder relevantere Information bieten. Das könnte deren Wert im Nahrungskontext erhöhen und in sozialem Lernen, welches auf sie gerichtet ist, resultieren. Selbst qualitativ ähnliche soziale Beziehungen zwischen juvenilen Raben und Dohlen bedingen somit nicht zwangsläufig ähnliche Ergebnisse im sozialen Lernen. Soziale Beziehungen sind nicht alleine für Lernmuster verantwortlich, sondern man muss vielmehr auch den Wert der räumlichen Verteilung aufgrund sozialer Beziehungen und die Nahrungsökologien verschiedener Arten in Betracht ziehen, um testbare Vorhersagen machen zu können wie sich die Beeinflussung von Verhalten durch soziales Lernen innerhalb einer Gruppe auswirken könnte.It was the aim of this study to investigate the influence of social relations between individuals on their social learning performance. I compared two phylogenetically closely related species, common ravens, Corvus corax, and jackdaws, Corvus monedula. The hypothesis tested suggests that tolerance and affiliation between individuals benefit their social learning performance. Transfer of information will be highest between individuals that are together in the same place at the same time. This will only be the case between certain individuals in non-egalitarian structured groups. Hence, particular individuals will be more influential models for certain others and information will spread among group members most likely via directed social learning. Raven and jackdaw groups show non-egalitarian social structures, providing the base for directed social learning. In a first step we therefore analyzed social relationships and dynamics in our groups of handraised and captive ravens and jackdaws, based on behavioural observations. Juvenile birds maintained affiliate relations with their nestmates, i.e. individuals that have been handraised together in the same nest, and also with their pair partners when adult (jackdaws). Analysis of jackdaw data also showed that these relationships meet the main characteristics of valuable relationships, such as spending more time in proximity, exchanging more friendly behaviours, such as allopreening and allofeeding and supporting each other more in agonistic interactions than do average dyads in the group. We therefore tested individuals in dyads of affiliated (nestmates) and non-affiliated (non-nestmates) individuals in stimulus enhancement experiments. The social learning performance of juvenile ravens supported the hypothesis tested because observers learned from affiliated individuals, their nestmates, more readily than from non-affiliated individuals. These findings are in alignment with the ravens` feeding ecology. Ravens intensively cache food and intra-specific competition at monopolizable food sources is high. For getting access to food and developing adequate cache protection strategies ravens need experiences with potential pilferers about their own caches being pilfered. They might gain most information from those individuals with which they spend most time in close proximity, i.e. their nestmates. This would increase the value of nestmates as a source of relevant information and may result in directed social learning from them. Jackdaws on the other hand learned more readily from non-affiliated (non-nestmates, non-pair partners) than from affiliated birds, which contradicts the hypothesis. In contrast to ravens, jackdaws forage mainly on distributed food sources and need spatial information about where feeding is profitable. They also spend most time in close proximity with affiliated individuals, i.e. nestmates and pair partners, which increases the probability that they gather similar information about their environment. However, spatially more distant individuals, which are more likely to be non-affiliated, may face different foraging situations and therefore provide different and/or more relevant information. This might increase the value of non-affiliated individuals in a feeding context and result in directed social learning from them. The main conclusion drawn from my data would be that even similar qualities of social relations between juvenile birds in ravens and jackdaws may not lead to similar outcomes in social learning experiments. Therefore, social relations do not solely account for learning patterns but also the value and use made of social spacing and and social relations, as well as different feeding ecologies have to be taken into account to provide testable predictions with regard to the pattern a behaviour spreads within a certain species

ICU mortality following ICU-acquired primary bloodstream infections according to the type of pathogen: A prospective cohort study in 937 Germany ICUs (2006-2015)

Objective: Mortality due to intensive care unit (ICU) acquired primary blood stream infections (PBSI) is related primarily to patient co-morbidities, types of pathogens and quality of care. The objective of this study is to determine the impact of various types of pathogen on ICU mortality. Methods: Data from the German National Nosocomial Infection Surveillance System of patients with PBSI from 2006 to 2015 was used for this analysis. A BSI is primary when the pathogen recognized is not related to an infection on another site. Only mono-microbial infections stratified into the 13 pathogens most frequently causing PBSI were considered. Univariate and multivariate risk factor analyses were performed using the following risk factors: Sex, age, length of stay, device use, time until onset of PBSI, type and size of hospital, type of ICU and type of pathogen. ICU mortality following S. aureus PBSI was used as the reference value. Results: A total of 4,556,360 patients with 16,978,882 patient days from 937 ICUs were considered in the analysis. Of 14,626 PBSI in total, 12,745 mono-microbial PBSI were included. The ICU mortality was 18.6%. Compared with S. aureus and adjusted by age, sex and type of ICU, S. maltophlfia was associated with significantly higher ICU mortality (OR 1.71; 95% CI 1.19-2.47) as followed by Enterococci (OR 1.20; 95% CI 1.06-1.36), Ecoli (OR 1.24; 95% CI 1.02-1.49), C. albicans (OR 1.37; 95% CI 1.16-1.61), non albicans Candida spp. (OR 1.49; 95% CI 1.18-1.88) and P. aeruginosa (OR 1.49; 95% CI 1.21-1.84). Coagulase negative Staphylococci were associated with significant lower ICU mortality (OR 0.86; 95% Cl 0.75-0.99). Conclusion: Because of the limitation of the study in adjusting for severity of illness and appropriateness of therapy, the differences between the pathogens may not only be explained by differences in virulence, but may reflect the prognosis after receiving the microbiological results and may therefore be useful for intensive care physicians

Recipients Affect Prosocial and Altruistic Choices in Jackdaws, Corvus monedula

Other-regarding preferences are a critical feature of human cooperation but to what extent non-human animals exhibit these preferences is a matter of intense discussion. We tested whether jackdaws show prosocial behaviour (providing benefits to others at no cost to themselves) and altruism (providing benefits to others while incurring costs) with both sibling and non-sibling recipients. In the prosocial condition, a box was baited on both the actor's and the recipient's side (1/1 option), whereas another box provided food only for the actor (1/0 option). In the altruistic condition, the boxes contained food for either the actor (1/0 option) or the recipient (0/1 option). The proportion of selfish (1/0 option) and cooperative (1/1 and 0/1 option, respectively) actors' choices was significantly affected by the recipients' behaviour. If recipients approached the boxes first and positioned themselves next to the box baited on their side, trying to access the food reward (recipient-first trials), actors were significantly more cooperative than when the actors approached the boxes first and made their choice prior to the recipients' arrival (actor-first trials). Further, in recipient-first trials actors were more cooperative towards recipients of the opposite sex, an effect that was even more pronounced in the altruistic condition. Hence, at no cost to the actors, all recipients could significantly influence the actors' behaviour, whereas at high costs this could be achieved even more so by recipients of different sex. Local/stimulus enhancement is discussed as the most likely cognitive mechanism to account for these effects

No increase of device associated infections in German intensive care units during the start of the COVID-19 pandemic in 2020

Background: The COVID-19 pandemic may have had a substantial impact on the incidence of device-associated healthcare-associated infections (HAI), in particular in intensive care units (ICU). A significant increase of HAI was reported by US hospitals when comparing incidence rates from 2019 and 2020. The objective of this study was to investigate the development of the most relevant device-associated HAI in German ICUs during the year 2020 as compared to 2019. Methods: We utilized the data of the ICU component of the German National Reference Center for Surveillance of Nosocomial Infections (KISS = Krankenhaus-Infektions-Surveillance-System) for the period 2019-2020. We focused on central line-associated bloodstream infections (CLABSI), catheter-associated urinary tract infections (CAUTI), ventilator-associated lower respiratory infections (VALRTI) and bloodstream infections associated with the use of Extracorporeal-Life-Support-Systems (ECLSABSI). Device use was defined as the number device days per 100 patient days; device-associated infection rates as the number of device-associated infections per 1000 device days. To compare the pooled means between the years and quarters we calculated rate ratios of device-associated infection rates with 95% confidence intervals by Poisson regression models. Results: The number of participating ICUs in the surveillance system decreased from 982 in 2019 to 921 in 2020 (6.2%). Device utilization rates increased significantly for central lines and ventilator use. VALRTI rates and CAUTI rates decreased in 2020 compared with 2019, however, no increase was shown for CLABSI or ECLSABSI. This result was also confirmed when the corresponding quarters per year were analyzed. Conclusions: The lack of an increase in device-associated healthcare associated infections (HAI) in German ICUs may be due to the lower overall incidence of COVID-19 cases in Germany in 2020 compared with US, to a very high availability of ICU beds per 100,000 inhabitants compared with many other countries, and a change in the ICU patient mix due to numerous elective procedures that were postponed during the first two waves. The primary reason seems to be that only 7% of all ICU patients in Germany in 2020 were COVID-19 patients

Slip rates variability and sediment mobilization on a shallow landslide in the northern Swiss Alps

Geomorphic and morphometric data imply that process rates of the Schimbrig landslide, located in the Entle watershed (Central Switzerland), are still limited by the elevation of the LGM base level. At present, the Entle watershed is in a stage of adjusting to the lowered post-glacial base level as indicated by knick zones in the trunk stream. Some thousands of years later when these knick zones will reach the Schimbrig site, we anticipate a substantial increase in process rates and sediment flux for the landslide. The pattern of slip rates was measured on the Schimbrig landslide over a 14-months period. We propose that a Bingham plastic model explains much of how measured slip rates are linked to the observed topography, climatic variations and thickness variability of the landslide mass. This model explains why slip rates have been highest where the thickness of the material is substantially higher. It also explains why slip rates are highest in late summer/autumn and early spring. It appears then that snow melt in spring and decreasing temperatures in late summer/autumn potentially result in a high retention of the pore water and thus in a low viscosity of the material, which, in turns, promotes slip rates. Interestingly, an extreme rainstorm like the one of August 2005 only had a local impact on the landslide mass by triggering small scale earth flows and debris flows. This implies that the earth slide material does not directly respond to an episodic pattern of rainfall. Such precipitation events, however, superimpose a smaller-scale imprint on the landslide relie

Concordance of copy number abnormality detection using SNP arrays and Multiplex Ligation-dependent Probe Amplification (MLPA) in acute lymphoblastic leukaemia

In acute lymphoblastic leukaemia, MLPA has been used in research studies to identify clinically relevant copy number abnormality (CNA) profiles. However, in diagnostic settings other techniques are often employed. We assess whether equivalent CNA profiles are called using SNP arrays, ensuring platform independence. We demonstrate concordance between SNP6.0 and MLPA CNA calling on 143 leukaemia samples from two UK trials; comparing 1,287 calls within eight genes and a region. The techniques are 99% concordant using manually augmented calling, and 98% concordant using an automated pipeline. We classify these discordant calls and examine reasons for discordance. In nine cases the circular binary segmentation (CBS) algorithm failed to detect focal abnormalities or those flanking gaps in IKZF1 probe coverage. Eight cases were discordant due to probe design differences, with focal abnormalities detectable using one technique not observable by the other. Risk classification using manually augmented array calling resulted in four out of 143 patients being assigned to a different CNA risk group and eight patients using the automated pipeline. We conclude that MLPA defined CNA profiles can be accurately mirrored by SNP6.0 or similar array platforms. Automated calling using the CBS algorithm proved successful, except for IKZF1 which should be manually inspected