In a changing world, large carnivores are making a significant comeback in Europe. Despite this success for conservation and ecosystem functioning, the coexistence of humans with such species is a challenge for societies worldwide. One of the main conflicts is attacks on livestock by wolves and brown bears. To protect livestock, practices are recommended that have been used successfully in countries where large carnivores have never become extinct. Sheep and goats are the most vulnerable livestock species to large carnivore attacks. In Austria, they are particularly at risk on alpine pastures, where they tend to graze unattended and unprotected. In this study, we developed an algorithm that can predict suitable prevention measures against large carnivore attacks on sheep and goats for each individual alpine pasture in the Austrian Alps. The prevention measures considered are electric fencing and shepherding with herding dogs, livestock guard dogs and night pens. We show that all sheep and goats on the Austrian alpine pastures can be protected by these measures, but this includes moving some of the animals to other pastures. This algorithm was validated by field visits to 22 alpine pastures. These results show firstly that damage prevention is possible in Austria, even on alpine pastures. However, these results are based solely on technical feasibility, such as terrain, land cover and capacity, rather than operational and institutional feasibility, such as labour, agreements, acceptance and costs. These results also show that it will require major changes, because these measures are costly and, perhaps more importantly, will break with some local traditions, because some of the sheep and goats will have to be moved to other alpine pastures. Public support must therefore include not only subsidies for the prevention measures themselves, but also technical and logistical support to make this change feasible.

Abstract Background Understanding and predicting the dynamics of rodent populations, particularly for endangered or pest species, requires knowledge of potential background factors. We collected long-term data on the abundance of European ground squirrels, Spermophilus citellus, in 64 colonies as part of the Hungarian Biodiversity Monitoring System to investigate the abiotic factors that could explain the spatial and temporal dynamics of populations in Hungary. We used information theory-based modelling and multi-model inference to investigate the effects of environmental and climate variables on relative population densities, using monitoring records of burrow counts as proxies for density collected annually between 2000 and 2018. We examined data carefully for any clues of inconsistencies, errors, or missing data, which resulted in 57% of the complete dataset. Results Our generalised additive models (GAM) with splines identified geographical location, year, and principal components reflecting winter temperature, precipitation, and summer temperature to affect population densities. Contour plots derived from the best GAM model uncovered increasing density in the Kiskunság and Kisalföld meso-regions with favourable water management characteristics and decreasing densities in the northern and southern regions, which in fact, cover floodplain of River Tisza and other flash-flood regions. Ambient temperature and precipitation of the wettest and warmest months during hibernation and summer contributed most to counts fluctuations, though these factors were dwarfed by spatial effects. Increased temperatures and aridification in the Kiskunság, because of the warming Pannonian ecoregion, seemed to positively affect counts. Conclusions Analysis of our reduced dataset indicated unidentified local factors or a spatial effect on demographic variability of ground squirrel populations. Those fluctuations underscore the necessity of research and management on local populations to identify the reasons of declines and adapt management accordingly to stop or change decreasing population trajectories.

In Africa, hares (Lepus spp.) show a high variability in external phenotypes. Species identification, delimitation, and distinction are difficult, due to the generally shallow evolutionary divergence of species, high intraspecific phenotypic variability, potentially complex reticulate evolutionary scenarios, and absence of relevant data across large areas. Our microsatellite and mitochondrial (mt) CR1 sequence data of hares from Tunisia with four different coat color morphs revealed high levels of gene flow both in nuclear and mt gene pools but no relevant partitioning of genetic variability parallel to the four coat color types. Nuclear and mt gene pool correspondence was at a very low level, and no phylogenetic gaps were observed in the mtDNA. Our results indicate only one hare species with different coat colors in Tunisia that shows no signals of reticulate evolution or incipient speciation. Because of potential reticulate evolutionary signals, especially in the mtDNA and the probably high adaptive significance of coat colors and patterns, external phenotypes combined with mtDNA alone may not serve as good proxies for species delimitation in hares from wide ranges in Africa. Combined nuclear and mtDNA population genetic and phylogenetic data allow more complex inferences on current and ancestral evolutionary processes for species identification and delimitation.

The external phenotypic variation of brown hares (Lepus europaeus) from Türkiye could represent climate-related adaptation, despite low neutral population genetic differentiation. Here, we investigated whether minor occlusal character variation of brown hares, previously used in phylogenetic or phylogeographic contexts in hare species, exhibit phylogenetic or ecogenetic variation in Türkiye, i.e., whether it corresponds to neutral population differentiation or climate variation in Türkiye. We used multi-model inference, i.e., model ranking and model averaging for binary coded occlusal traits to distinguish possible phylogenetic (neutral population genetic) from ecogenetic (climatic) effects. Our logistic models revealed a few statistically important phylogenetic and ecogenetic signals, taking into account sex, age category, skull size, and geographic coordinates of sample location. All of the latter explanatory factors/variables also showed some effects on character variation, independent of population genetic and climate effects. This could be due to a developmental (ontogenetic) background of occlusal character variation. Our calculations of pairwise phenetic distances, i.e., C.A.B. Smith´s Mean Measures of Divergence (MMD) between populations were similarly low or non-significant as previously studied microsatellite-based genetic differentiation between populations. Notably, the MMD values were based on only three occlusal characters, the only ones that showed significant variation between at least two populations. Importantly, unlike the traditional MMD calculation, our character modeling was not limited by the lack of significant spatial variation in occlusal characters; moreover, it considered all explanatory factors that were of interest simultaneously, when testing phylogenetic or ecogenetic character causation.

Song complexity has been identified as one song characteristic important in female choice, whereas its role in male-male interactions is less clear and not much is known which song characteristics are specifically important for territorial defense. In Acrocephalus warblers, males seem to increase song complexity towards females but reduce it during territorial disputes. One possibility to reduce song complexity could be achieved by repeating individual syllables. In this context here we examined the importance of males repeating syllables in male-male interactions. We hypothesis that repeating syllables signals a males general fighting ability, aggressive status or willingness to attack. In a playback experiment we investigated the behavioral response of unmated, territorial Eurasian reed warbler ( Acrocephalus scirpaceus ) males towards two simultaneously singing intruders whereby the song of the two simulated intruders differs in the degree of syllable repetitions. The response of the territory owner was determined by using several behavioral parameters. Our results revealed that males approached faster and stayed significantly longer near the song with few syllable repetitions. However, the proportion of males approaching the song with high or low syllable repetitions first, as well as the minimal distance to which males approach to the two song types did not differ as well. Thus, the weaker response towards the high repetitive song playback suggests territorial males to be more intimidated by the aggressive nature of that song type.

The non-stationarity in habitat selection of expanding populations poses a significant challenge for spatial forecasting. Focusing on the grey wolf ( Canis lupus ) natural recolonization of Germany, we compared the performance of different distribution modelling approaches for predicting habitat suitability in unoccupied areas. Furthermore, we analysed whether grey wolf showed non-stationarity in habitat selection in newly colonized areas, which will impact the predictions for potential habitat. Germany. Using telemetry data as presence points, we compared the predictive performance of five modelling approaches based on combinations of distribution modelling algorithms—GLMM, MaxEnt and ensemble modelling—and two background point selection strategies. We used a homogeneous Poisson point process to draw background points from either the minimum convex polygons derived from telemetry or the whole area known to be occupied by wolves. Models were fit to the data of the first years and validated against independent data representing the expansion of the species. The best-performing approach was then used to further investigate non-stationarity in the species' response in spatiotemporal restricted datasets that represented different colonization steps. While all approaches performed similarly when evaluated against a subset of the data used to fit the models, the ensemble model based on integrated data performed best when predicting range expansion. Models for subsequent colonization steps differed substantially from the global model, highlighting the non-stationarity of wolf habitat selection towards human disturbance during the colonization process. While telemetry-only data overfitted the models, using all available datasets increased the reliability of the range expansion forecasts. The non-stationarity in habitat selection pointed to wolves settling in the best areas first, and filling in nearby lower-quality habitat as the population increases. Our results caution against spatial extrapolation and space-for-time substitutions in habitat models, at least with expanding species.

AimThe non-stationarity in habitat selection of expanding populations poses a significant challenge for spatial forecasting. Focusing on the grey wolf (Canis lupus) natural recolonization of Germany, we compared the performance of different distribution modelling approaches for predicting habitat suitability in unoccupied areas. Furthermore, we analysed whether grey wolf showed non-stationarity in habitat selection in newly colonized areas, which will impact the predictions for potential habitat.LocationGermany.MethodsUsing telemetry data as presence points, we compared the predictive performance of five modelling approaches based on combinations of distribution modelling algorithms-GLMM, MaxEnt and ensemble modelling-and two background point selection strategies. We used a homogeneous Poisson point process to draw background points from either the minimum convex polygons derived from telemetry or the whole area known to be occupied by wolves. Models were fit to the data of the first years and validated against independent data representing the expansion of the species. The best-performing approach was then used to further investigate non-stationarity in the species' response in spatiotemporal restricted datasets that represented different colonization steps.ResultsWhile all approaches performed similarly when evaluated against a subset of the data used to fit the models, the ensemble model based on integrated data performed best when predicting range expansion. Models for subsequent colonization steps differed substantially from the global model, highlighting the non-stationarity of wolf habitat selection towards human disturbance during the colonization process.Main ConclusionsWhile telemetry-only data overfitted the models, using all available datasets increased the reliability of the range expansion forecasts. The non-stationarity in habitat selection pointed to wolves settling in the best areas first, and filling in nearby lower-quality habitat as the population increases. Our results caution against spatial extrapolation and space-for-time substitutions in habitat models, at least with expanding species.

Wolves have large spatial requirements and their expansion in Europe is occurring over national boundaries, hence the need to develop monitoring programs at the population level. Wolves in the Alps are defined as a functional population and management unit. The range of this wolf Alpine population now covers seven countries: Italy, France, Austria, Switzerland, Slovenia, Liechtenstein and Germany, making the development of a joint and coordinated monitoring program particularly challenging. In the framework of the Wolf Alpine Group (WAG), researchers developed uniform criteria for the assessment and interpretation of field data collected in the frame of different national monitoring programs. This standardization allowed for data comparability across borders and the joint evaluation of distribution and consistency at the population level. We documented the increase in the number of wolf reproductive units (packs and pairs) over 21 years, from 1 in 1993-1994 up to 243 units in 2020-2021, and examined the pattern of expansion over the Alps. This long-term and large-scale approach is a successful example of transboundary monitoring of a large carnivore population that, despite administrative fragmentation, provides robust indexes of population size and distribution that are of relevance for wolf conservation and management at the transnational Alpine scale.

Exposing female house mice ( Mus musculus ) to male urinary scent accelerates their sexual development (Vandenbergh effect). Here, we tested whether exposing juvenile male mice to females’ urine similarly influences male growth and size of their sexual organs. We exposed three-week old male house mice to female urine or water (control) for ca. three months. We found that female-exposed males grew significantly faster and gained more body mass than controls, despite all males being reared on a controlled diet, but we detected no differences in males' muscle mass or sexual organs. In contrast, exposing juvenile males to male urine had no effect their growth. We tested whether the males' accelerated growth imposed functional trade-offs on males' immune resistance to an experimental infection. We challenged the same male subjects with an avirulent bacterial pathogen ( Salmonella enterica ), but found no evidence that faster growth impacted their bacterial clearance, body mass or survival during infection compared to controls. Our results provide the first evidence to our knowledge that juvenile male mice accelerate their growth when exposed to the urine of adult females, though we found no evidence that increased growth had negative trade-offs on immune resistance to infectious disease.

IntroductionThe two-humped Bactrian camel (Camelus bactrianus) is a large, even-toed ungulate native to the steppes of Central Asia. Domestic Bactrian camels are economically important in Mongolia and other Central Asian countries. These animals are used for transport, milk and meat production, and camel racing which is a great culture of nomads. Eimeriosis, also known as coccidiosis, is considered as an economically important parasitic diseases in Bactrian camels. There is still considerable lack of data concerning the spectrum of monoxenous Eimeria species, their epizootiology as well as their precise life cycles in Bactrian camels. This study was performed to determine the prevalence of Eimeria species in camelids from southern part of Mongolia.MethodsA total of 536 fresh camel fecal samples (n = 536) collected from herds located in five different Aimags (provinces) of Mongolia were examined. Eimeria spp. oocysts were isolated using the sugar flotation technique, and after sporulation, oocysts were identified by morphometric evaluation.ResultsWe identified the most common Eimeria species infecting Mongolian Bactrian camels: Eimeria cameli (22.3%), Eimeria rajasthani (37.3%) and Eimeria dromedarii (27.7%). Interestingly, mixed infections were detected in 24.8% (n = 133) of the samples, while 39.0% (n = 209) were negative for coccidian stages. To investigate the immunogenetic response of the Mongolian Bactrian camels to Eimeria spp. infection, we screened the genetic diversity in a functional important immune response gene of the major histocompatibility complex (MHC). We detected two polymorphic sites in the MHC class II DRA exon 2, which translated into one non-synonymous and one synonymous amino acid (aa) change.DiscussionThe resulting aa alleles were not significantly associated with any of the three detected Eimeria species infections, nor could we show heterozygote advantage in non-infected Mongolian Bactrian camels. Further investigations on molecular epidemiology, in vitro culture, pathogenicity and host–parasite interactions will be necessary to better understand the impact of eimeriosis in Bactrian camels.

ZusammenfassungMit dem anwachsenden Wolfsbestand nehmen auch die Übergriffe auf Nutztiere in Deutschland von Jahr zu Jahr zu. In einem Punkt sind sich Landwirtschaft, Naturschutz und Politik einig: Wolfsübergriffe auf Nutztiere sollen nachhaltig minimiert werden. Darüber, wie dieses Ziel am besten erreicht werden kann, gibt es jedoch unterschiedliche Ansichten. In der öffentlichen Debatte werden Forderungen nach einem vereinfachten Abschuss von Wölfen oder einer generellen Bejagung immer lauter. Dabei wird davon ausgegangen, dass durch solche Maßnahmen Nutztierschäden durch Wölfe nachhaltig minimiert werden könnten.Bevor Maßnahmen des Wildtiermanagements angewandt werden, braucht es klare Zielvorgaben. Die erste Frage muss daher lauten: Was ist das primäre Ziel der Managementmaßnahme? Auf Basis wissenschaftlicher Evidenz muss dann vorab evaluiert werden, ob die in Frage kommenden Maßnahmen geeignet sind, das Ziel zu erreichen. Dies ist zwingend, wenn die Maßnahmen auch das Töten von empfindungsfähigen und noch dazu streng geschützten Tieren beinhalten. Um überprüfen zu können, wie wirksam die gewählten Managementmaßnahmen im konkreten Einsatz sind, werden Kriterien zur Bewertung des Erfolgs benötigt.In diesem Kapitel gehen wir der Frage nach, welche Managementmaßnahmen nach aktuellem Wissensstand geeignet sind, das Ziel, Wolfsübergriffe auf Nutztiere nachhaltig zu minimieren, zu erreichen. Wir erläutern zunächst, warum Wölfe Nutztiere töten und ob es einen Zusammenhang zwischen der Anzahl der Wölfe und der Höhe der Nutztierschäden gibt. Dafür untersuchen wir unter anderem die Daten von Wolfsübergriffen auf Nutztiere in Deutschland. Anhand einer umfangreichen Literaturübersicht analysieren wir, ob die folgenden Managementmaßnahmen geeignet sind, Wolfsübergriffe auf Nutztiere nachhaltig zu minimieren: 1) eine generelle Bejagung von Wölfen, 2) die selektive Entnahme von einzelnen schadensverursachenden Wölfen und 3) nicht-letale Herdenschutzmethoden. Abschließend legen wir Empfehlungen zu einem evidenzbasierten und lösungsorientierten Wolfsmanagement in Bezug auf den Wolf-Nutztierkonflikt vor.In Deutschland steigen mit der Zunahme der Wolfsterritorien auch die Übergriffe auf Schafe und Ziegen. Allerdings unterscheidet sich die Stärke des Anstiegs zwischen den Bundesländern erheblich. Einzelne Bundesländer erreichen bei der gleichen Anzahl an Wolfsterritorien sehr unterschiedliche Schadensniveaus. Dies deutet darauf hin, dass das Ausmaß der Schäden nicht allein durch die Anzahl der Wölfe bestimmt wird. Wir vermuten, dass die Unterschiede im Schadensniveau vor allem in der unterschiedlichen Umsetzung von Herdenschutzmaßnahmen in den einzelnen Bundesländern begründet sind.Die Ergebnisse der Literaturrecherche bezüglich der Wirksamkeit von letalen und nicht-letalen Managementmaßnahmen zum Schutz von Nutztieren zeigen klar: Eine generelle Bejagung von Wölfen führt nicht zu einer Reduktion von Nutztierschäden. Es gibt keine wissenschaftlichen Belege dafür, dass durch eine Bejagung die Schäden deutlich und nachhaltig verringert werden, es sein denn, der Bestand wird drastisch reduziert oder ganz ausgelöscht. Das ist in Deutschland und in der Europäischen Union bei aktueller Rechtslage nicht möglich. Im Gegensatz zu einer undifferenzierten Bejagung des Wolfs kann der gezielte Abschuss von Einzeltieren wirksam sein, wenn es sich tatsächlich um Individuen handelt, die gelernt haben, empfohlene funktionstüchtige Schutzmaßnahmen zu überwinden. Allerdings sind solche Fälle selten, und es ist schwierig in der freien Natur, ein bestimmtes Individuum sicher zu identifizieren und zu töten. Nicht-letale Herdenschutzmaßnahmen sind im Vergleich zu letalen Maßnahmen deutlich besser geeignet, eine nachhaltige Reduktion der Schäden zu erreichen. Der einzige Weg, um in Koexistenz mit Wölfen eine dauerhafte Reduktion von Schäden an Nutztieren zu erreichen, ist die fachgerechte Umsetzung von Herdenschutzmaßnahmen in breiter Fläche. Übergriffe auf Nutztiere lassen sich zwar auch dadurch nicht vollständig verhindern, sie können jedoch durch korrekt angewandte Herdenschutzmaßnahmen deutlich reduziert werden.Das Wissen, wie Schäden an Weidetieren durch Herdenschutzmaßnahmen verringert werden können, ist auch in Deutschland vorhanden. Viele Tierhaltende haben hier inzwischen ein hohes Maß an Fachkompetenz entwickelt. Die Erfahrung aus den vergangenen 20 Jahren zeigt allerdings auch, dass die Auszahlung von Fördergeldern für Herdenschutzmittel allein nicht ausreicht, um die Anzahl der Übergriffe deutlich zu senken. Es muss auch gewährleistet werden, dass die fachliche Expertise für die korrekte Anwendung und Wartung zur Verfügung steht. Vor allem in Gebieten mit Prädations-Hotspots sollte aktiv auf die Tierhaltenden zugegangen werden und sollten die Gründe für die vermehrten Übergriffe analysiert und abgestellt werden.Bisher fehlen aus Deutschland Daten zur Funktionstüchtigkeit der geförderten und im Einsatz befindlichen Schutzmaßnahmen. Solche Daten sind notwendig, um zu verstehen, warum trotz steigender Präventionsausgaben die Nutztierschäden teilweise auch in Gebieten mit jahrelanger Wolfspräsenz nicht zurückgehen. Sie sind zudem die Grundlage für wissenschaftliche Studien zu möglichen Unterschieden in der Wirksamkeit verschiedener Herdenschutzmethoden. Daten zur Funktionstüchtigkeit von geförderten Herdenschutzmaßnahmen sollten zumindest stichprobenartig gesammelt werden, unabhängig davon, ob es in dem jeweiligen Gebiet Wolfsübergriffe gibt. Neben der Untersuchung der rein technischen Aspekte des Herdenschutzes ist es ebenso wichtig herauszufinden, wie die Akzeptanz gegenüber Herdenschutzmaßnahmen bei den Tierhaltenden verbessert und deren Eigenmotivation erhöht werden kann. Hierfür sind Daten zur Umsetzbarkeit und Akzeptanz der eingesetzten Herdenschutzmaßnahmen erforderlich. Nutztierhaltende sollten schon in die Konzeption entsprechender Studien mit eingebunden werden, um sicherzustellen, dass die Fragen untersucht werden, deren Beantwortung für sie am dringendsten ist.Der Weg von einem emotionsbasierten zu einem evidenzbasierten Wolfsmanagement führt über wissenschaftlich robuste Daten und Analysen. Entsprechende Untersuchungen sind nur in enger Zusammenarbeit zwischen Weidetierhaltung und Wissenschaft möglich. Basierend auf der Fachkompetenz und den praktischen Erfahrungen der Weidetierhaltenden kann die Wissenschaft helfen, die Herdenschutzmaßnahmen zu identifizieren und weiterzuentwickeln, die Nutztierübergriffe am effektivsten reduzieren.SummaryAs the wolf population grows, the number of attacks on livestock in Germany also increases from year to year. Agriculture, nature conservation and politics agree on one point: that wolf attacks on livestock should be reduced sustainably. However, there are differing views on how this goal can best be achieved. In the public debate, calls for simplified shooting of wolves or general hunting are becoming louder and louder. The assumption is that such measures could sustainably reduce livestock damage caused by wolves.Before wildlife management measures are applied, clear objectives are needed. The first question, therefore, must be: What is the primary objective of the management measure? Based on scientific evidence, it must be evaluated in advance whether the measures under consideration are suitable for achieving the objective. This is mandatory if the measures include the killing of sentient animals, particularly if they are strictly protected. Criteria for evaluating if the objective was reached are needed in order to be able to verify how effective the selected management measures are when applied.In this chapter, we address the question of which management measures are suitable, based on current knowledge, to achieve the goal of sustainably reducing wolf attacks on livestock. We first explain why wolves kill livestock and whether there is a relationship between the number of wolves and the amount of livestock damage. To do this, we examine, among other things, data on wolf attacks on livestock in Germany. Based on an extensive literature review, we analyse whether the following management measures are suitable to sustainably reduce wolf attacks on livestock: 1) a general hunting of wolves, 2) the selective removal of individual wolves causing damage, and 3) non-lethal livestock protection methods. Finally, we present recommendations for evidence-based and solution-oriented wolf management with respect to wolf-livestock conflict.In Germany, as wolf territories increase, attacks on sheep and goats also increase. However, the magnitude of the increase differs considerably among the federal states. Individual federal states achieve very different levels of damage with the same number of wolf territories. This suggests that the extent of damage is not solely determined by the number of wolves. We suspect that the differences in damage levels are mainly due to the different implementation of livestock protection measures in the individual federal states.The results of the literature review regarding the effectiveness of lethal and non-lethal management measures to protect livestock clearly show that general hunting of wolves does not reduce livestock damage. There is no scientific evidence that hunting significantly and sustainably reduces damage, unless the wolf population is drastically reduced or completely eradicated. This is not possible in Germany and in the European Union under the current legal situation. In contrast to an undifferentiated hunting of the wolf, the targeted shooting of individual animals can be effective if they are actually individuals that have learned to overcome recommended functional livestock protection measures. However, such cases are rare and it is difficult in the field to safely identify and kill a specific individual. Non-lethal livestock protection measures are much better at achieving sustained reductions in damage compared to lethal measures. The only way to achieve a lasting reduction of damage to livestock in coexistence with wolves is the professional implementation of livestock protection measures on a broad scale. Non-lethal livestock protection measures do not completely prevent attacks on livestock. However, if correctly applied they can significantly reduce wolf caused damages on livestock.The knowledge of how to reduce livestock depredation by wolves through herd protection measures is also available in Germany. Many livestock farmers have developed a high level of expertise in this field. However, experience from the past 20 years also shows that the funding of livestock protection measures alone is not enough to significantly reduce the number of wolf attacks. It is also necessary to ensure that technical expertise is available for proper application and maintenance of the measures. Especially in areas with predation hotspots, livestock owners should be actively approached and the reasons for increased attacks analysed and remedied.To date, there is a lack of data from Germany on the functionality of funded and applied protection measures. Such data are necessary to understand why, despite increasing prevention expenditures, livestock damage has not decreased in some cases, even in areas where wolves have been present for years. Moreover, such data are the basis for scientific studies on possible differences in the effectiveness of different livestock protection methods. Data on the functionality of funded protection measures should be collected at least on a random basis, regardless of whether there are wolf attacks in the respective area. In addition to investigating the purely technical aspects of herd protection, it is equally important to find out how the acceptance towards livestock protection measures can be improved among livestock owners and how their self-motivation can be increased. This requires data on the feasibility and acceptance of the applied protection measures. Livestock keepers should be involved already in the conception of appropriate studies to ensure that the investigations will answer the most urgent questions for them.The path from emotion-based to evidence-based wolf management is through scientifically robust data and analysis. Appropriate research is only possible through close collaboration between livestock owners and science. Based on the expertise and practical experience of farmers, science can help identify and improve the livestock protection measures that most effectively reduce wolf attacks on livestock.

In wild boar, Sus scrofa, from Europe, domestic pig-typical ancestry is traced at varying levels. We hypothesised wild boar with pig-typical gene pool characteristics, i.e., “introgression”, congregate more in peri-urban habitats, because of less shyness and better adaptation to anthropogenic stress. We used 16 microsatellites to study introgression levels of 375 wild boar from peri-urban Vienna, Austria, and rural regions in comparison to commercial slaughter pigs, Mangaliza, and Turopolje pigs. We also expected more introgression in locations of warmer climates and lower precipitation. Despite discrimination of wild boar and pigs with 99.73% and 97.87% probability, respectively, all wild boars exhibited pig-typical gene pool characteristics, mostly at a very low level. Recent hybridisation was suspected in only 0.53% of wild boar, corresponding to the current largely indoor pig breeding/rearing in the region, with no chance of natural gene exchange between pigs and wild boar. Rather, pig ancestry in wild boar stems from incomplete gene pool differentiation during domestication and/or historical introgressions, when free-ranging pig farming was common. Individual introgression levels were lower in wild boar from peri-urban habitats, possibly reflecting the largely historical absence of pig farms there. Moreover, a marginal precipitation effect, but no temperature effect on introgression was observed. The latter, however, needs to be explored further by a more comprehensive data set.

The genes of the major histocompatibility complex (MHC) are among the best candidates for studying adaptive variation driven often by pathogen-mediated selection. However, diversity of these genes might be differently shaped by selective and non-selective evolutionary mechanisms. In this study, we assessed the spatial distribution of MHC class II DRB exon 2 gene diversity in hares from Tunisia (Lepus capensis) across a steep ecological gradient and tried to disentangle the driving mechanisms shaping the observed diversity. We also compared the current data with previous results from the MHC class II DQA and DQB loci of the same individuals. We found a relatively high level of diversity and spatial differentiation similar to that observed earlier for DQA and DQB. We also detected clear evidence of positive selection acting on the DRB gene. Nevertheless, recombination was considered as a more important process shaping the evolution of the DRB locus. Our information theory-based models revealed statistically meaningful climate effects on the occurrence of some alleles (i.e., protein variants), regardless of their geographical distribution patterns, supposedly reflecting adaptation to spatial pathogen variation.

Air-borne chemicals are highly abundant sensory cues and their use in navigation might be one of the major evolutionary mechanisms explaining the development of olfaction in animals. Despite solid evidence for the importance of olfaction in avian life (e.g., foraging or mating), the importance of chemical cues in avian orientation remains controversial. In particular, songbirds are sorely neglected models, despite their remarkable orientation skills. Here we show that great tits ( Parus major ) require olfactory cues to orientate toward winter-feeding sites within their home range after displacement. Birds that received an olfaction-depriving treatment were impaired in homing. However, the return rates between olfaction-deprived and control individuals did not differ. Birds with decreased perception of olfactory cues required more time to return to the winter feeding sites. This effect became apparent when the distance between the releasing and capture sites was greater. Our results indicate that even in a familiar environment with possible visual landmarks, scent cues might serve as an important source of information for orientation.

The Eurasian lynx (Lynx lynx) population in Switzerland serves as a source for reintroductions in neighboring countries. In 2016–2017, three lynx from the same geographical area were found seropositive for feline immunodeficiency virus (FIV) in the framework of an international translocation program. This novel finding raised questions about the virus origin and pathogenicity to lynx, the emerging character of the infection, and the interpretation of serological results in other lynx caught for translocation. Archived serum samples from 84 lynx captured in 2001–2016 were retrospectively tested for FIV antibodies by Western blot. All archived samples were FIV-negative. The three seropositive lynx were monitored in quarantine enclosures prior to euthanasia and necropsy. They showed disease signs, pathological findings, and occurrence of co-infections reminding of those described in FIV-infected domestic cats. All attempts to isolate and characterize the virus failed but serological data and spatiotemporal proximity of the cases suggested emergence of a lentivirus with antigenic and pathogenic similarities to FIV in the Swiss lynx population. A decision scheme was developed to minimize potential health risks posed by FIV infection, both in the recipient and source lynx populations, considering conservation goals, animal welfare, and the limited action range resulting from local human conflicts. Development and implementation of a cautious decision scheme was particularly challenging because FIV pathogenic potential in lynx was unclear, negative FIV serological results obtained within the first weeks after infection are unpredictable, and neither euthanasia nor repatriation of multiple lynx was acceptable options. The proposed scheme distinguished between three scenarios: release at the capture site, translocation, or euthanasia. Until April 2021, none of the 40 lynx newly captured in Switzerland tested FIV-seropositive. Altogether, seropositivity to FIV was documented in none of 124 lynx tested at their first capture, but three of them seroconverted in 2016–2017. Diagnosis of FIV infection in the three seropositive lynx remains uncertain, but clinical observations and pathological findings confirmed that euthanasia was appropriate. Our experiences underline the necessity to include FIV in pathogen screenings of free-ranging European wild felids, the importance of lynx health monitoring, and the usefulness of health protocols in wildlife translocation.

For most animals, the rearing environment is an important factor influencing early offspring development and behaviour. Also, in altricial birds, where the rearing environment (nest) is usually restricted, it is known that if sufficient nest space is provided, offspring show social interactions and a variety of other behaviours. In fact, the available nest space has been identified as an important determinant for the occurrence or outcome of social interactions. In this context, we predict different behaviours like food acquisition, intra-brood competition, comfort behaviour or defecation activities also happen at specific sites within the nest and allow differential nest-space use. We further predict, that even offspring within a brood may differently experience their rearing environment. In line with this, e.g. nestling age, brood size or parental food allocation rules could be influential factors. In this study, we therefore investigated offspring nest-space use in altricial hoopoe nestlings (Upupa epops) raised in spacious nest boxes. In particular, we focused on nest-space use in relation to four major offspring behaviours, namely successful food acquisition, aggressive interactions, comfort and resting behaviour and defecation, additionally including parental feeding strategy (feeding from inside or outside the nest box), nestling age and brood size as potentially influential factors. Our results reveal that nestlings do not use the nest space equally but use specific locations for different purposes. Our results further suggest that beside behaviour also offspring age, brood size and parental feeding strategy influence their nest-space use. In conclusion, differential nest-space use can occur even in nestlings and already at an early age. Thus, nest space seems to be an important nest quality feature determining not only nest-space use but also affects offspring social interactions.

BACKGROUND:Animal mitochondria play a central role in energy production in the cells through the oxidative phosphorylation (OXPHOS) pathway. Recent studies of selection on different mitochondrial OXPHOS genes have revealed the adaptive implications of amino acid changes in these subunits. In hares, climatic variation and/or introgression were suggested to be at the origin of such adaptation. Here we looked for evidence of positive selection in three mitochondrial OXPHOS genes, using tests of selection, protein structure modelling and effects of amino acid substitutions on the protein function and stability. We also used statistical models to test for climate and introgression effects on sites under positive selection.RESULTS:Our results revealed seven sites under positive selection in ND4 and three sites in Cytb. However, no sites under positive selection were observed in the COX1 gene. All three subunits presented a high number of codons under negative selection. Sites under positive selection were mapped on the tridimensional structure of the predicted models for the respective mitochondrial subunit. Of the ten amino acid replacements inferred to have evolved under positive selection for both subunits, six were located in the transmembrane domain. On the other hand, three codons were identified as sites lining proton translocation channels. Furthermore, four codons were identified as destabilizing with a significant variation of Δ vibrational entropy energy between wild and mutant type. Moreover, our PROVEAN analysis suggested that among all positively selected sites two fixed amino acid replacements altered the protein functioning. Our statistical models indicated significant effects of climate on the presence of ND4 and Cytb protein variants, but no effect by trans-specific mitochondrial DNA introgression, which is not uncommon in a number of hare species.CONCLUSIONS:Positive selection was observed in several codons in two OXPHOS genes. We found that substitutions in the positively selected codons have structural and functional impacts on the encoded proteins. Our results are concordantly suggesting that adaptations have strongly affected the evolution of mtDNA of hare species with potential effects on the protein function. Environmental/climatic changes appear to be a major trigger of this adaptation, whereas trans-specific introgressive hybridization seems to play no major role for the occurrence of protein variants.

Following historical restrictions to isolated and patchy populations, large carnivores like the brown bearUrsus arctosare recolonizing areas of their historical range in Europe. This process is of particular interest in the Alps and the Dinaric Mountains in Central Europe, the largest mountain range in the continent and of transboundary conservation interest. To assist policies focused on the expansion of bears in this region, we conducted habitat selection analyses accounting for different behaviour between three populations (Trentino, pre-Alps and Dinaric) where bears have adapted to different intensities of human persecution. We then identified the landscape connectivity between these fragmented populations that could provide viable habitat and stepping-stone patches for recolonization. To handle individual and population differences in space-use, we modelled habitat selection per population from an individual-level and integrated results into a multi-population model using scale-integrated resource selection functions. We then calculated connectivity indices per patch and the contribution of various countries involved in bear management in the region to enhancing connectivity. Bears mostly selected forests across all populations while preferences for other variables differed among populations and across scales. Bears in the highly humanized habitats of the Trentino selected the most intricate topography, where they could more easily find refuge. Suitable but fragmented habitat patches were common all over the study area with the most suitable habitat in the pre-Alpine and Dinaric populations. However, the Trentino and pre-Alp included the patches of maximum/medium priority as stepping-stones to connect these populations. Transboundary initiatives for the conservation of existing habitat and the facilitation of connectivity are required to promote current bear expansion and reduce conflicts with humans. Our framework provides insight into the adaptive behaviour of large carnivores in human-dominated landscapes in a conservation context.

In this study, we investigated the influence of different weather aspects on breeding performance, food supply and nest-space use in hoopoe offspring (Upupa epops). Camera recordings of 88 nests were used to examine how ambient environmental conditions influence food supply, offspring nest-space use and the trade-off nestlings face regarding the two mainly used locations in the nest. Therefore, we provide a comprehensive analysis involving different factors including weather parameters together with food provisioned to nestlings on different temporal scales to identify the factors having the most influence on nest-space use. We found that different breeding conditions significantly influenced how nestlings used the nest. During excessively humid weather, nestlings spent more time under the entrance hole when small food was delivered. However, nestlings supplied with large prey more often remained hidden in the distant area, despite the adverse weather situation. In all three aspects and temporal scales, our analysis confirmed that prey was the most important factor influencing offspring nest-space use, suggesting a crucial role of large insects for hoopoes. Finally, we found that long-term effects of weather affect overall food provisioned to nestlings and thus offspring behaviour. We provide evidence that parental feeding location and prey size, which are in turn influenced by weather conditions, are the most influential factors for nest-space use. This study expands our knowledge of parent–offspring communication and how environmental factors may lead to differential nest-space use, which may be regarded as the earliest form of habitat preference in birds. Nests are usually constrained in space but designed to protect offspring from the environment while giving them limited possibilities to express behavioural diversity. This is particularly true for bird nests, where nestlings are usually packed in close contact with one another and without much space for movement, except begging. Here we demonstrate that nest features, such as available nest space together with environmental conditions surrounding a nest, influence nestling strategies and behaviours, including social interactions between nest mates, which further leads to fitness consequences. Our results seem to be of great importance for habitat selection theory in birds, in particular regarding the early development of habitat preferences (imprinting) and use. On the other hand, the result may also have important implications for conservation issues given that nestling behaviour may be used as a determinant of environmental quality.

AbstractBackgroundIn Europe, golden jackals (Canis aureus) have been expanding their range out of the southern and southeastern Balkans towards central Europe continually since the 1960s. Here, we investigated the level of functional diversity at the MHC class IIDLA-DQA1exon 2 in golden jackal populations from Bulgaria, Serbia, and Hungary. Specifically, we tested for positive selection on and geographic variation at that locus due to adaptation to supposedly regionally varying pathogenic landscapes. To test for potential fitness effects of different protein variants on individual body condition, we used linear modeling of individual body mass indexes (bmi) and accounted for possible age, sex, geographical, and climatic effects. The latter approach was performed, however, only on Serbian individuals with appropriate data.ResultsOnly three differentDLA-DQA1alleles were detected, all coding for different amino-acid sequences. The neutrality tests revealed no significant but positive values; there was no signal of spatial structuring and no deviation from the Hardy–Weinberg equilibrium across the studied range of expansion. However, we found a signal of trans-species polymorphism and significant test results for positive selection on three codons. Our information-theory based linear modeling results indicated an effect of ambient temperature on the occurrence of individualDLA-DQA1genotypes in individuals from across the studied expansion range, independent from geographical position. Our linear modeling results of individual bmi values indicated that yearlings homozygous forDLA-DQA1*03001reached values typical for adults contrary to yearlings carrying other genotypes (protein combinations). This suggested better growth rates and thus a possible fitness advantage of yearlings homozygous forDLA-DQA1*03001.ConclusionsOur results indicate a demographic (stochastic) signal of reducedDLA-DQA1exon 2 variation, in line with the documented historical demographic bottleneck. At the same time, however, allelic variation was also affected by positive selection and adaptation to varying ambient temperature, supposedly reflecting geographic variation in the pathogenic landscape. Moreover, an allele effect on body mass index values of yearlings suggested differential fitness associated with growth rates. Overall, a combination of a stochastic effect and positive selection has shaped and is still shaping the variation at the studied MHC locus.