Open-cast mines are valuable secondary habitats for many European amphibian species. Threatened pioneer amphibians, such as natterjack toads (Epidalea calamita), are especially bound to them and lignite mining districts in Central Europe have become a stronghold of the species. However, these secondary habitats are shrinking due to the coal phase-out. Studies on factors limiting E. calamita metamorphic success in mining ponds are missing, but they are essential to inform conservation efforts in post-mining landscapes. Thus, we surveyed the metamorphic success of E. calamita, along with amphibian species richness, in two lignite mines in Central Germany. We further recorded important pond parameters, such as morphometry, water chemistry, hydroperiod and vegetation. Since species-rich habitats do not necessarily support specialist species, we hypothesized that E. calamita metamorphic success and amphibian species richness depend on different pond characteristics. To test this hypothesis, we used ordination, generalized linear mixed models (GLMMs) and multimodel inference to determine the most important predictors for (i) E. calamita breeding activity, (ii) metamorphic success and (iii) amphibian species richness. Except for water acidity (pH), E. calamita metamorphic success and amphibian species richness depended on different parameters. Precipitation, (short) hydroperiod of ephemeral ponds (or young age of perennial ponds) and breeding site identity were important for E. calamita, while pond size, depth and water surface stability were important for species richness. We therefore argue that, in post-mining landscapes, clusters of ponds that address natterjack toad needs should be managed and constructed spatially separated from ponds targeting a wider range of species.

The endangered natterjack toad ( Epidalea calamita ) faces ongoing habitat loss, requiring effective conservation measures. Field surveys must therefore address its highly variable detectability in terrestrial habitats. We investigated the factors influencing capture success comparing two methods: artificial cover boards (ACBs) and wildlife detection dogs (WDDs). We first analysed environmental and training factors influencing toad detectability for four detection dogs with varying experience using a binomial generalized linear model (GLM). Then, we compared capture success of ACBs and WDD transects (deploying two dogs) considering weather and habitat type using negative binomial GLMs. Across 200 tests, each detection dog displayed a unique learning curve, with performance influenced mainly by dog behaviour, wind, test blindness and insect presence. Detection rates across dogs levelled off at 87.2% (75.7%–94.8%). Capture success of both methods under real‐deployment conditions was separately analysed for juvenile and (sub‐)adult toads by calculating a success rate. For juvenile toads, capture success was primarily influenced by capture method, habitat type and study year, while adult toads capture success mainly depended on habitat type and precipitation. Overall, WDDs (mean rate juvenile toads = 4.15, mean rate adult toads = 5.61) showed higher success rates than ACBs (mean rate juvenile toads = 0.51, mean rate adult toads = 4.73), particularly in dense and versatile habitats. Practical implication . This study provides practical guidance for the selection and implementation of survey methods for E. calamita , identifying critical factors to consider when designing a study to maximize survey success. Dog handlers should be able to adapt search and training strategies to their dogs' individual pace and limitations and keep environmental influences in mind. Both ACBs and WDDs are suitable methods for detecting E. calamita in terrestrial habitats; however, detection dogs are particularly useful in densely vegetated areas, for finding juveniles and for covering larger regions more efficiently. Success rates for adult toads increase in favourable habitat and climatic conditions, such as warmer temperatures and sufficient moisture. Our findings provide a framework that may be extended to the monitoring and conservation of other amphibian species.

Post-mining areas are populated by many taxa and are particularly important for pioneer species whose primary habitats, such as dynamic floodplains, have largely been degraded. For such species, habitats must be optimally managed beyond the end of mining activities to preserve their populations; therefore knowledge of their habitat requirements is needed. To provide such evidence, we investigated the microhabitat selection of juvenile and (sub)adult natterjack toads (Epidalea calamita), a pioneer amphibian with high conservation priority, at two structurally contrasting lignite mining sites (unreclaimed vs. reclaimed) in Central Germany. Over three years, we conducted multiple surveys using artificial coverboards complemented by microclimate measurements. We applied multi-season occupancy models to examine the effects of microhabitat characteristics, such as vegetation cover, slope, and distance to breeding ponds, on the detection and occupancy probabilities for different life stages. While the unreclaimed sites supported high rates of occupancy and low rates of local extinction — especially for (sub)adults — few (sub)adult toads remained in the reclaimed area after a first year with high recruitment. Moreover, we found that microhabitat preferences between juveniles and (sub)adults partly diverged, as juveniles preferably occupied flat areas near breeding ponds, while (sub)adults preferred steeper microhabitats further from ponds. These findings provide evidence that management strategies must consider life stage-specific habitat requirements to maintain viable populations of pioneer species like E. calamita. We conclude that preserving unreclaimed, structurally diverse post-mining landscapes is vital in conservation of pioneer amphibians.

Over the last decades, the worldwide decline of amphibian populations has become a major concern of researchers and conservationists. Studies have reported a diversity of trends, with some species strongly declining, others remaining stable and still others increasing. However, only a few species have been monitored annually for a long period of time by specific monitoring programmes. Instead, there are many heterogeneous datasets that contain observations of amphibians from professional surveys as well as diverse citizen science and other voluntary surveys. The use of these data brings a number of challenges, raising concerns about their validity and use in ecological research and conservation. We assessed to what extent such heterogeneous occurrence data can provide information on the status and trends of amphibians by contrasting different approaches to overcoming challenges with the data, using the German state of Saxony as an example. We assessed the effects of data processing decisions to infer absences, the use of survey method information and the statistical model (generalised linear mixed-effect occurrence model [GLMM] versus occupancy-detection model) and compared the trends with expert opinions (Red Lists). The different data processing decisions mainly led to similar annual occupancy estimates, newts being an exception. Annual occupancy estimates were typically less certain when attempting to account for the effects of survey methods, which could be explained by many missing values on methods. Separate models for drift fence data reduced the uncertainty in the annual occurrence probability estimates of the GLMM models, but uncertainty remained high for occupancy-detection models. For both methods, strong peaks and troughs in the annual occupancy estimates occurred for several species, which were not biologically plausible. Some peaks align with periods of lower sampling effort and were probably caused by shifts in the sampling locations or target species amongst years. Only for three species (Bufotes viridis, Hyla arborea and Pelophylax esculentus) were the trend results consistent amongst approaches and with expert opinions. For most other species, some inconsistencies appeared amongst models or approaches, indicating that trend assessments are sensitive to analytical choices. While heterogeneous data have proved useful for other taxa, our results highlight the complexity of using them for amphibians. We strongly recommend better harmonisation of data collection and metadata documentation, including explicit absence data and, if available, abundance data, to enable more robust trend assessments in the future.

Alpine ecosystems harbour a rich and highly specialised biodiversity, which is particularly susceptible to anthropogenic disturbances such as habitat loss and fragmentation as well as to climate change. Combined with other forms of land-use conversion, construction and maintenance of ski resorts can have severe consequences on alpine biodiversity. In this study, we show how one amphibian and two reptile species, namely Rana temporaria, Zootoca vivipara and Vipera berus, respond to such impacts by means of a multi-season occupancy analysis. We found all three species both in and outside ski-runs, showing that these habitats do not necessarily preclude their occurrence. Contrarily, this is influenced more by microhabitat availability, such as ground vegetation, humid areas and rock cover, rather than by macro-characteristics like elevation or habitat type. Moreover, we found a climatic influence on the year-to-year occupancy change of the species, with activity-month conditions being more relevant than overwintering ones. Our results demonstrate how, in the specific case of reptiles and amphibians, ski resorts do not necessarily limit species' occurrence and that a mild series of management actions might secure the species' persistence in the area.

AimSquamate fitness is affected by body temperature, which in turn is influenced by environmental temperatures and, in many species, by exposure to solar radiation. The biophysical drivers of body temperature have been widely studied, but we lack an integrative synthesis of actual body temperatures experienced in the field, and their relationships to environmental temperatures, across phylogeny, behaviour and climate.LocationGlobal (25 countries on six continents).TaxaSquamates (210 species, representing 25 families).MethodsWe measured the body temperatures of 20,231 individuals of squamates in the field while they were active. We examined how body temperatures vary with substrate and air temperatures across taxa, climates and behaviours (basking and diel activity).ResultsHeliothermic lizards had the highest body temperatures. Their body temperatures were the most weakly correlated with substrate and air temperatures. Body temperatures of non-heliothermic diurnal lizards were similar to heliotherms in relation to air temperature, but similar to nocturnal species in relation to substrate temperatures. The correlation of body temperature with air and substrate temperatures was stronger in diurnal snakes and non-heliothermic lizards than in heliotherms. Body-substrate and body-air temperature correlations varied with mean annual temperatures in all diurnal squamates, especially in heliotherms. Thermal relations vary with behaviour (heliothermy, nocturnality) in cold climates but converge towards the same relation in warm climates. Non-heliotherms and nocturnal species body temperatures are better explained by substrate temperature than by air temperature. Body temperature distributions become left-skewed in warmer-bodied species, especially in colder climates.Main ConclusionsSquamate body temperatures, their frequency distributions and their relation to environmental temperature, are globally influenced by behavioural and climatic factors. For all temperatures and climates, heliothermic species' body temperatures are consistently higher and more stable than in other species, but in regions with warmer climate these differences become less pronounced. A comparable variation was found in non-heliotherms, but in not nocturnal species whose body temperatures were similar to air and substrate irrespective of the macroclimatic context.

Increasing agricultural intensification, combined with land transformation and fragmentation, poses significant threats to biodiversity. While extensively cultivated landscapes serve as vital refuges against biodiversity loss, they are modified by land abandonment and intensification. Orchard meadows in Central Europe represent traditional extensive land management systems, exhibiting high biodiversity. Comprising cultivated grasslands and scattered fruit trees, orchard meadows feature structures rich in different habitats supporting a diverse flora and fauna. However, their decreasing economic importance in recent decades has resulted in severe degradation or abandonment. Despite their importance for biodiversity conservation, there remains no comprehensive overview of orchard meadow biodiversity and management in Central Europe. This review aims to summarize existing knowledge on orchard meadows’ role in biodiversity conservation and the effects of management practices on habitat diversity and quality at both smaller (structure and microhabitats, local scale) and larger scales (surrounding landscape, regional scale). The first part focuses on orchard meadow biodiversity, including both plants and animals and their link to landscape-scale factors. Biodiversity in orchard meadows is predominantly affected by patch size, determining species richness and composition, and connectivity to neighbouring orchard meadows, influencing species migration and recolonization success. The second part evaluates management impacts, illustrating differences in the benefits of mowing versus grazing across taxonomic groups. An intermediate management intensity for orchard meadows determines their conservation value in terms of species composition, varying among different taxonomic groups. To prevent area loss and abandonment of orchard meadows, we advocate for political and public support, along with incentives for farmers to maintain their biodiversity.

Within the scope of the Helmholtz Metadata Collaboration (HMC), the ADVANCE project – Advanced metadata standards for biodiversity survey and monitoring data: supporting of research and conservation – aimed at supporting rich metadata generation with interoperable metadata standards and semantic artefacts that facilitate data access, integration and reuse across terrestrial, freshwater and marine realms. HMC's mission is to facilitate the discovery, access, machine-readability, and reuse of research data across and beyond the Helmholtz Association. We revised, adapted and expanded existing metadata schemas, vocabularies and thesauri to build a FAIR metadata schema and a metadata entry form built on it for users to provide their metadata instances focused on biodiversity monitoring data. The schema is FAIR because it is both machine-interpretable and follows domain-relevant community standards. This report provides a general overview of the project results and instructions on how to access, re-use and complete the metadata form.

Within the scope of the Helmholtz Metadata Collaboration, the ADVANCE project – Advanced metadata standards for biodiversity survey and monitoring data: supporting of research and conservation – aimed at supporting rich metadata generation with interoperable metadata standards and semantic artifacts that facilitate data access, integration and reuse across terrestrial, freshwater and marine realms. To this end, we revised, adapted and expanded existing metadata schemas, vocabularies and thesauri to build a FAIR metadata schema and a metadata entry form built on it for users to provide their metadata instances focused on biodiversity monitoring data. The schema is FAIR because it is both machine-interpretable and follows domain-relevant community standards. This report provides a general overview of the project results and instructions on how to access, re-use and complete the metadata form.

Monitoring of wildlife populations is essential for their conservation and requires a carefully chosen methodology. We compared survey effectiveness of reptiles using coverboards and visual encounter surveys in two study sites in the Italian Alps with similar habitats and reptile communities. The two sites shared similar methodologies, cover boards and visual encounter surveys (VES), except for the temporal approach, with one employing a long-lasting monitoring scheme and the other operating on a much shorter time-frame. Coverboards were placed two years before the beginning of the monitoring in the first site, while they were installed only for ten days and then removed each year in the second site. Similarly, VES were spread across the whole reptile activity season (May-September) in the first site, while conducted over nine consecutive days in the second site. Although the observation rate of any species was mainly associated with its relative abundance, reptiles preferred long-established coverboards and all three species present ( Zootoca vivipara , Anguis veronensis and Vipera berus ) were found underneath them. Only Zootoca vivipara used recently installed ones. On the other hand, short-term daily visual encounter surveys led to a much higher observation rate of Z. vivipara than those spread over the entire season. Our results suggest that coverboards may provide a valuable monitoring tool for reptiles when projects are conducted over long periods. Conversely, when only short-term assessments are possible, no real difference exists between the two methods and observation rate is more influenced by the species abundance than by the chosen method.

Context Habitat connectivity can stabilise animal populations by facilitating immigration and genetic exchange, but it increases the risk of infectious diseases being spread by hosts. Chytridiomycosis caused by Batrachochytrium salamandrivorans ( Bsal ) threatens European salamander diversity. The extent to which the connectivity of populations of fire salamanders ( Salamandra salamandra ) contributes to the spread of Bsal remains unclear. Objectives We analysed the impact of habitat connectivity of fire salamanders on the spread of Bsal . Moreover, we show how local salamander abundance is associated with habitat connectivity over a five-year period. Methods We developed fire salamander habitat suitability models (HSMs) for the Eifel area (Germany), currently considered the core of the range of Bsal in Europe. Habitat models were used to calculate pairwise resistance between salamander occurrences to test whether Bsal presence and salamander abundance were associated with habitat connectivity. Results Fire salamanders are widely distributed in the Eifel. Solid bedrock and topographic positioning were important predictors of stream suitability as breeding habitats, while deciduous forests and grassland cover determined overall fire salamander habitat suitability along with breeding habitat suitability. Bsal -positive salamander occurrences were better-connected than Bsal -negative or untested occurrences. Nevertheless, fire salamander larvae were more abundant in well-connected sites. Conclusion The connection of salamander populations by suitable habitat seems to support local salamander abundance while facilitating the spread of Bsal. In situ conservation measures counteracting host species connectivity to interrupt Bsal transmission pathways must be implemented with caution, as they may weaken the demographic advantages of connectivity.

Amphibian species are declining worldwide, with a negative trend affecting both rare and widespread species. There is increasing evidence that resources must be allocated not only toward the monitoring of rare and charismatic species; however, the attention toward abundant species has often been minimal. Here, we describe the strong reduction in the numbers of several widespread amphibian species over the last 3 years observed in three independent amphibian monitoring studies conducted in an alpine, floodplain, and urban landscape in Italy, Germany, and Russia, respectively. The decline was particularly strong in juveniles, but adults and egg clutches were also affected. Such declining rates, if prolonged in the future years, will likely pose a serious threat to the populations' ability to recover and might increase extinction risk also in abundant and widespread species.

Vertical stratification and host tree species are factors with a high influence on the structure of communities of xylobiont beetles. However, little is known about how this influence varies between common and rare species. Based on estimated species richness, we compared alpha and beta diversity patterns of common and rare species in the canopy of the Leipzig floodplain forest to assess their response to vertical stratification and tree species. We used two measures of rarity: threat level in red lists and abundance based on octaves. The understory displayed a significantly higher number of common species than the canopy strata. Conversely, the canopy strata harbored a higher number of rare species. Turnover was always dominant over richness differences in beta diversity partitions. Using Raup–Crick null models and non-metric multidimensional scaling, we found that the vertical strata accounted for 19% of the overall beta diversity of common species and for 15% of the overall beta diversity of rare species. The tree species accounted for 7% of the overall beta diversity of the common species and 3% of the beta diversity of the rare species. Our results indicate that studies carried out in the understory alone do not allow drawing conclusions regarding the biodiversity in the canopy strata, and thus regarding the overall community structure of xylobiont beetles in the canopy.

Habitat loss can increase the susceptibility of individuals to parasitic infections, and hence, parasite bad can serve as an early warning indicator of stress before the persistence of a population becomes threatened. In this study, we tested the effects of patch characteristics, isolation and landscape composition resulting from habitat loss on the tick bad of individuals from central populations of the Eastern Green Lizard Lacerta viridis. We identified the spatial scale at which each landscape composition parameter has the strongest effect and evaluated its effects at this scale. Additionally, we tested the relationships between tick bad and population density and body condition (BC) to understand possible mechanisms that determine tick loads in populations. We found that tick bad was not affected by host population density. BC was not found to be affected by tick bad, but BC did have a negative effect on lizards' tick loads. The proportion of habitat and cropland in the landscape and patch size had positive effects on tick loads, whereas the proportion of urbanized areas, iso-lation and perimeter/area ratio had negative effects. We discuss our finding in the context of how the landscape can affect tick populations and other potential hosts. We conclude that tick bad can be a suitable early warning indicator of nega-tive effects of habitat loss, reflecting the susceptibility of lizards to infestation. We suggest that this indicator be included in monitoring programs aiming at evaluating the status of populations of L. viridis in modified landscapes, and recom-mend that conservation measures be focused on the protection of habitat at broader scales to compensate negative effects of cropland and urbanized areas occurring at small scales.

Large‐scale biodiversity databases have great potential for quantifying long‐term trends of species, but they also bring many methodological challenges. Spatial bias of species occurrence records is well recognized. Yet, the dynamic nature of this spatial bias – how spatial bias has changed over time – has been largely overlooked. We examined the spatial bias of species occurrence records within multiple biodiversity databases in Germany and tested whether spatial bias in relation to land cover or land use (urban and protected areas) has changed over time. We focused our analyses on urban and protected areas as these represent two well‐known correlates of sampling bias in biodiversity datasets. We found that the proportion of annual records from urban areas has increased over time while the proportion of annual records within protected areas has not consistently changed. Using simulations, we examined the implications of this changing sampling bias for estimation of long‐term trends of species' distributions. When assessing biodiversity change, our findings suggest that the effects of spatial bias depend on how it affects sampling of the underlying land‐use change drivers affecting species. Oversampling of regions undergoing the greatest degree of change, for instance near human settlements, might lead to overestimation of the trends of specialist species. For robust estimation of the long‐term trends in species' distributions, analyses using species occurrence records may need to consider not only spatial bias, but also changes in the spatial bias through time.

Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging.

Over the last 40 years, a growing number of restoration projects have been implemented to improve the ecological conditions of highly degraded rivers and their floodplains. Despite considerable investment in these projects, information is still limited about the effectiveness and the success of such river restoration measures, mainly due to a lack of standardised and interdisciplinary assessment approaches. During the project ‘Wilde Mulde—Restoration of a dynamic riverine landscape in Central Germany’, we implemented hydromorphological restoration measures (installation of large wood, removal of rip‐rap, reconnection of a former river side‐arm) along a lowland river in Central Germany. We carried out intensive scientific monitoring of biodiversity, hydromorphology, ecosystem functions and services, as well as socio‐economic aspects. A Before/After‐Control/Impact (BACI) design was used to identify the spatial and temporal effects of the restoration measures and to distinguish them from changes caused by background variation. For this, we used a comprehensive set of indicators, including abiotic (flow velocity, diversity of riverbed topography, and flow resistance), biological (ecosystem respiration, macroinvertebrates, fish, carabids, vegetation, and birds) and socio‐economic (acceptance and public awareness) indicators as well as the ecosystem service indicator aesthetic quality of the landscape. To meet the inherent challenges of such a large‐scale field experiment, like unpredictable environmental conditions, we used an experimental approach that allowed us to demonstrate a measurable success of the implemented restoration measures. The majority of the abiotic and some of the biological and socio‐economic indicators at the restored sites approached values of a natural reference site while already deviating from values of a nonnatural reference site two years after restoration. In addition to the applied interdisciplinary approach, multiple scales of field investigations and data analyses are essential as key components for evaluating successful river and floodplain restoration projects.