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Agricultural intensification, afforestation and land abandonment are major drivers of biodiversity loss in semi‐natural grasslands across Europe. Reversing these losses requires the reinstatement of plant–animal interactions such as pollination. Here we assessed the differences in species composition and patterns of plant‐pollinator interactions in ancient and restored grasslands and how these patterns are influenced by landscape connectivity, across three European regions (Belgium, Germany and Sweden).We evaluated the differences in pollinator community assemblage, abundance and interaction network structure between 24 ancient and restored grasslands. We then assessed the effect of surrounding landscape functional connectivity (i.e. green infrastructure, GI) on these variables and tested possible consequences on the reproduction of two model plants, Lotus corniculatus and Salvia pratensis.Neither pollinator richness nor species composition differed between ancient and restored grasslands. A high turnover of interactions across grasslands was detected but was mainly due to replacement of pollinator and plant species. The impact of grassland restoration was consistent across various pollinator functional groups, whereas the surrounding GI had differential effects. Notably, bees, butterflies, beetles, and dipterans (excluding hoverflies) exhibited the most significant responses to GI variations. Interestingly, networks in restored grasslands were more specialised (i.e. less functionally redundant) than in ancient ones and also showed a higher number of insect visits to habitat‐generalist plant species. Landscape connectivity had a similar effect, with habitat‐specialist plant species receiving fewer visits at higher GI values.Fruit set in S. pratensis and L. corniculatus was unaffected by grassland type or GI. However, the fruit set in the specialist S. pratensis increased with the number of pollinator visits, indicating a positive correlation between pollinator activity and reproductive success in this particular species.Synthesis and applications. Our findings provide evidence of the necessity to enhance ecosystem functions while avoiding biotic homogenisation. Restoration programs should aim at increasing landscape connectivity which influences plant communities, pollinator assemblages and their interaction patterns. To avoid generalist species taking over from specialists in restored grasslands, we suggest reinforcing the presence of specialist species in the latter, for instance by means of introductions, as well as increasing the connectivity to source populations. [ABSTRACT FROM AUTHOR]

Wild boar is among the most abundant ungulates in Europe and its spread is locally creating concerns as a major threat to biodiversity. However, through their rooting activity, wild boars could play an effective role in the creation of specific microhabitat resources for plants and animals. Here, we tested the hypothesis that wild boar affects the habitat suitability to threatened butterflies, by evaluating the influence of rooting on multiple key aspects of the biology and ecology of the Mediterranean endemic Zerynthia cassandra. Namely, we used Z. cassandra as a model to test the effects of wild boar rooting on adult foraging opportunities, host plant occurrence, and oviposition site selection. We found that herbaceous communities disturbed by wild boar rooting have a higher proportion of plants representing nectar resources for early-flying butterflies. We also discovered that wild boar rooting positively influences the occurrence and abundance of the larval host plant of Z. cassandra, as well as the butterfly site selection for egg-laying. Our results indicate that wild boars may locally prove beneficial to endangered butterflies by favoring habitat quality and availability, and their role as ecosystem engineers should thus be further investigated to improve species and habitat management and conservation actions. [ABSTRACT FROM AUTHOR]

Agriculture intensification threatens farmland bird populations because, among other reasons, it reduces the availability of food resources required to rear their offspring. In our study, we sampled and analyzed total arthropod abundance, biomass and richness, and orthopteran and coleopteran abundance and biomass in different agricultural habitats (alfalfa fields, stubble fields, grazed fields, and field margins) across 4 study localities with different levels of agriculture abandonment–intensification, comparing between areas used and not used by one of the most threatened farmland birds in Europe, the little bustard (Tetrax tetrax), during the chick‐rearing season. Field margins were the taxonomically richest habitat, while alfalfa fields presented significantly higher total arthropod abundance and biomass than other habitats. All arthropod variables were the highest in the localities with clear conservation‐focused agrarian management, and the lowest in the most intensive one. Areas used by little bustards had higher orthopteran and coleopteran abundance and biomass than nonused areas, except for coleopteran biomass in grazed fields. These results highlight the relevance of these arthropods for the species, the importance of dry alfalfa fields as food reservoirs in this critical time of year, the food scarcity in sites where agrarian management disregards farmland bird conservation, and the role of stubbles as providers of food resources during the chick‐rearing season in areas used by the species. The adequate management of alfalfa fields and stubbles to provide those key resources seems crucial to improve little bustard breeding success. [ABSTRACT FROM AUTHOR]

Agricultural intensification and subsequent landscape homogenisation have caused severe losses of insects across major parts of Europe. In consequence, most animal and plant populations today exist in small and isolated habitat patches. Thus, there is an urgent need to increase landscape permeability to foster the exchange of individuals and thereby to promote the long‐term persistence of populations and species. Corridors can help to connect local habitats and populations. Nonetheless, whether species use a corridor and how species behave in a corridor strongly depend on species' ecology and the quality of the corridor.In this study, we analysed the behaviour of 753 individuals of five butterfly species of the subfamily Satyrinae (Coenonympha pamphilus, C. arcania, Maniola jurtina, Melanargia galathea, and Erebia medusa) in a high‐quality habitat, in two corridors with different habitat qualities, and in arable fields.Butterflies undertake more frequent and much longer flights in arable fields, and a more range‐restricted behaviour with perching and visiting of flowers in corridors and inside the original high‐quality habitat. Specialist butterflies only rarely leave the corridor and fly into the matrix if compared with generalist butterfly species. Furthermore, the relative difference in the probability of leaving a corridor was much more pronounced between the two corridor qualities for specialists than for generalists.In conclusion, corridors with high habitat quality, such as many flowering plants, support species and population persistence. Specialist species especially respond to corridor quality, such as the availability of flowers or a calcareous grassland‐like species composition. [ABSTRACT FROM AUTHOR]

The objective of our study was to evaluate the hypothesis that the constraints on the expansion of the range of the common genet ( Genetta genetta ) in Europe are limitations derived from the species’ patterns of habitat selection. From a sample of 2073 genet occurrence data and using species distribution models (SDM) built with Maxent, our results show that temperature-related variables were the main factor explaining the current distribution of the species. The maximum winter temperature was by far the most important environmental constraint of the presence of the species, with genets showing a preference for higher temperatures in the two coldest seasons of the year. Genets appeared also associated to Mediterranean zones, preferred mid-elevations and were more often present in habitats dominated by sclerophyllous vegetation. Our results stongly support the view that the influence of temperature is a major limiting factor that impedes the spread of the genet northwards and eastwards into continental Europe and limits its distribution. Nevertheless, the current spread of its colonization fronts could lead to future changes in its distribution, so it would seem that its expansion has not yet finished. [ABSTRACT FROM AUTHOR]

Highlights: [•] Comparison of methods for hydromorphological assessment. [•] Statistic values calculated from HD models provide good information. [•] The urban Boise River shows hydromorphological good conditions, compared to Europe. [•] Need for transferability of methods to compare rivers in different regions. [ABSTRACT FROM AUTHOR]

Sediment quantity and quality are key considerations in the sustainable management of fluvial systems. Increasing attention is being paid to the role of aquatic biota as geomorphic agents, capable of altering the composition, mobilization and transport of fluvial sediments at various spatiotemporal scales. In this paper invasive species are presented as a special case since: (1) populations may not be constrained by factors characteristic of their native habitats; and (2) they represent a disturbance to which the system may not be resilient. Discussion is centred on the signal crayfish which has rapidly colonized catchments in Europe and Japan, but the hypotheses and models presented provide a framework applicable to other invasive species. This paper explores the mechanisms by which signal crayfish may influence sediment dynamics from the patch scale to the catchment scale. There is potential for signal crayfish to impact significantly on river sediments and morphology as a function of their interactions with river bed and bank material, and with other aquatic organisms, combined with their large body size and aggressive nature, their presence in very high densities, and the lack of effective mitigation strategies. Potential catchment-scale management issues arising from these factors include habitat degradation, mobilization of sediment-associated nutrients and contaminants, and sediment-related flood risks. Further interdisciplinary research is required at the interface between freshwater ecology, fluvial geomorphology and hydraulics, in order to quantify the significance and extent of these impacts. The paper points to the key research agendas that may now emerge. [ABSTRACT FROM PUBLISHER]

Approximately 75% of the Victorian Box-Ironbark ecosystem has been cleared since European settlement. There are few public land areas of high habitat quality, and significant Box-Ironbark remnant vegetation (BIR) is known to exist on private land. A landholder mail survey collected information about BIR to ascertain its size, use and habitat quality. Ground-truthing validated the landholder assessment of habitat quality. Livestock grazing had impacted Fifty percent of BIR, and approximately 20-50% was of moderate to high quality. Fifty four percent of BIR were less than 15 ha. Remnant size had the largest impact on quality, with larger remnants being of higher quality. [ABSTRACT FROM PUBLISHER]

Limited knowledge of dispersal for most organisms hampers effective connectivity conservation in fragmented landscapes. In forest ecosystems, deadwood-dependent organisms (i.e., saproxylics) are negatively affected by forest management and degradation globally. We reviewed empirically established dispersal ecology of saproxylic insects and fungi. We focused on direct studies (e.g., mark-recapture, radiotelemetry), field experiments, and population genetic analyses. We found 2 somewhat opposite results. Based on direct methods and experiments, dispersal is limited to within a few kilometers, whereas genetic studies showed little genetic structure over tens of kilometers, which indicates long-distance dispersal. The extent of direct dispersal studies and field experiments was small and thus these studies could not have detected long-distance dispersal. Particularly for fungi, more studies at management-relevant scales (1-10 km) are needed. Genetic researchers used outdated markers, investigated few loci, and faced the inherent difficulties of inferring dispersal from genetic population structure. Although there were systematic and species-specific differences in dispersal ability (fungi are better dispersers than insects), it seems that for both groups colonization and establishment, not dispersal per se, are limiting their occurrence at management-relevant scales. Because most studies were on forest landscapes in Europe, particularly the boreal region, more data are needed from nonforested landscapes in which fragmentation effects are likely to be more pronounced. Given the potential for long-distance dispersal and the logical necessity of habitat area being a more fundamental landscape attribute than the spatial arrangement of habitat patches (i.e., connectivity sensu strict), retaining high-quality deadwood habitat is more important for saproxylic insects and fungi than explicit connectivity conservation in many cases., (© 2018 Society for Conservation Biology.)