Coping with unpredictable environments: fine-tune foraging microhabitat use in relation to prey availability in an alpine species.

Microhabitat utilisation holds a pivotal role in shaping a species' ecological dynamics and stands as a crucial concern for effective conservation strategies. Despite its critical importance, microhabitat use has frequently been addressed as static, centering on microhabitat preference. Yet, a dynamic microhabitat use that allows individuals to adjust to fine-scale spatio-temporal prey fluctuations, becomes imperative for species thriving in challenging environments. High-elevation ecosystems, marked by brief growing seasons and distinct abiotic processes like snowmelt, winds, and solar radiation, feature an ephemeral distribution of key resources. To better understand species' strategies in coping with these rapidly changing environments, we delved into the foraging behaviour of the white-winged snowfinch Montifringilla nivalis, an emblematic high-elevation passerine. Through studying microhabitat preferences during breeding while assessing invertebrate prey availability, we unveiled a highly flexible microhabitat use process. Notably, snowfinches exhibited specific microhabitat preferences, favoring grass and melting snow margins, while also responding to local invertebrate availability. This behaviour was particularly evident in snow-associated microhabitats and less pronounced amid tall grass. Moreover, our investigation underscored snowfinches' fidelity to foraging sites, with over half located within 10 m of previous spots. This consistent use prevailed in snow-associated microhabitats and high-prey-density zones. These findings provide the first evidence of dynamic microhabitat use in high-elevation ecosystems and offer further insights into the crucial role of microhabitats for climate-sensitive species. They call for multi-faceted conservation strategies that go beyond identifying and protecting optimal thermal buffering areas in the face of global warming to also encompass locations hosting high invertebrate densities.

Species interactions and climate change: How the disruption of species co-occurrence will impact on an avian forest guild.

Interspecific interactions are crucial in determining species occurrence and community assembly. Understanding these interactions is thus essential for correctly predicting species' responses to climate change. We focussed on an avian forest guild of four hole-nesting species with differing sensitivities to climate that show a range of well-understood reciprocal interactions, including facilitation, competition and predation. We modelled the potential distributions of black woodpecker and boreal, tawny and Ural owl, and tested whether the spatial patterns of the more widespread species (excluding Ural owl) were shaped by interspecific interactions. We then modelled the potential future distributions of all four species, evaluating how the predicted changes will alter the overlap between the species' ranges, and hence the spatial outcomes of interactions. Forest cover/type and climate were important determinants of habitat suitability for all species. Field data analysed with N-mixture models revealed effects of interspecific interactions on current species abundance, especially in boreal owl (positive effects of black woodpecker, negative effects of tawny owl). Climate change will impact the assemblage both at species and guild levels, as the potential area of range overlap, relevant for species interactions, will change in both proportion and extent in the future. Boreal owl, the most climate-sensitive species in the guild, will retreat, and the range overlap with its main predator, tawny owl, will increase in the remaining suitable area: climate change will thus impact on boreal owl both directly and indirectly. Climate change will cause the geographical alteration or disruption of species interaction networks, with different consequences for the species belonging to the guild and a likely spatial increase of competition and/or intraguild predation. Our work shows significant interactions and important potential changes in the overlap of areas suitable for the interacting species, which reinforce the importance of including relevant biotic interactions in predictive climate change models for increasing forecast accuracy.

Assessing common birds' ecological requirements to address nature conservation in permanent crops: Lessons from Italian vineyards.

Viticulture has contributed to shaping cultural landscapes in several regions across all continents. Recent farming intensification is causing landscape homogenization and biodiversity loss in several of those areas, but knowledge about the impacts on biodiversity in vineyards is still scarce. Simplified agro-ecosystems resulting from intensification host mainly generalist and common species, which still play a key role in the regulation of ecosystems and in the provision of ecosystem services. We assessed the abundance of 11 common bird species at 47 linear transects in a vineyard-dominated landscape in Trentino (NE Italy), in both spring and winter, and analysed abundance variation in relation to three independent groups of predictors: landscape, management, and topographic-climatic variables. In the majority of species (7), abundance was primarily or considerably affected by landscape attributes. However, an additional 5 species were largely affected by management practices, often with conspicuous seasonal differences. Overall, landscape and management heterogeneity positively affected the abundance of 6 species. Vineyard cover (and in particular the new spalliera trellising system) was negatively related with the abundance of 6 species, with the strongest impacts occurring in winter. On the contrary, the cover of marginal habitats had major positive effects over 8 species. Hedgerows, tree rows, and dry stone walls, as well as traditional pergola vineyards and landscape and management heterogeneity should be conserved or restored in viticultural landscapes to promote the abundance of common bird species. This strategy would ensure the maintenance of the ecosystem services they provide, while promoting the general sustainability of the agroecosystem.

Direct and indirect causal effects of heterozygosity on fitness-related traits in Alpine ibex.

Heterozygosity-fitness correlations (HFCs) are a useful tool to investigate the effects of inbreeding in wild populations, but are not informative in distinguishing between direct and indirect effects of heterozygosity on fitness-related traits. We tested HFCs in male Alpine ibex (Capra ibex) in a free-ranging population (which suffered a severe bottleneck at the end of the eighteenth century) and used confirmatory path analysis to disentangle the causal relationships between heterozygosity and fitness-related traits. We tested HFCs in 149 male individuals born between 1985 and 2009. We found that standardized multi-locus heterozygosity (MLH), calculated from 37 microsatellite loci, was related to body mass and horn growth, which are known to be important fitness-related traits, and to faecal egg counts (FECs) of nematode eggs, a proxy of parasite resistance. Then, using confirmatory path analysis, we were able to show that the effect of MLH on horn growth was not direct but mediated by body mass and FEC. HFCs do not necessarily imply direct genetic effects on fitness-related traits, which instead can be mediated by other traits in complex and unexpected ways.

Contribution to the knowledge of the arthropods community inhabiting the winter-flooded meadows (marcite) of northern Italy.

BACKGROUND: Flooded semi-natural grasslands are endangered ecosystems throughout Europe. In Italy, amongst flooded meadows, one special type called "marcita" is strongly threatened. It is a stable flooded grassland used to produce green forage even during winter months due to the thermal properties of water coming from springs and fountains that prevent the soil from freezing. To date, some research has been carried out to investigate the role of the marcita for ornithological and herpetological communities. However, no comprehensive data on invertebrates inhabiting this particular biotope available. The aim of this study was to characterise the terrestrial entomological community of these typical winter-flooded meadows in northern Italy and, in particular, in six marcita fields located in the Ticino Valley Regional Park. We collected data on species richness and diversity of Carabidae, Staphylinidae, Araneae, Lepidoptera and Orthoptera inhabiting marcita during the summers of 2014 and 2015 and data on overwintering Coleoptera during the winter of 2014-2015. Amongst the collected species, we identified those highly linked to this habitat. NEW INFORMATION: We found a total of 47 ground beetle species, 35 rove beetle species, 29 spider species, one Lucanidae, 16 butterfly species and 24 grasshopper and cricket species. Most of the species were collected during the summers of 2014 and 2015, while some others were also, or exclusively, overwintering (17 ground beetles, four rove beetles and one Lucanidae) and were collected during the winter of 2014-2015.Marcita fields hosted specialised species and species typical of hygrophilous habitats, amongst which are included the butterfly Lycaena dispar, the ground beetle Dolichus halensis and the grasshopper Chrysochraon dispar. This study represents the first contribution to the knowledge of terrestrial arthropod communities associated with this particular type of winter-irrigated meadow in Europe and confirms the importance of this biotope for invertebrate conservation in agricultural landscapes.

Seeding and Overseeding Native Hayseed Support Plant and Soil Arthropod Communities in Agriculture Areas.

Using native seed mixtures to create or recover grassland habitats in rotation to crops or in strips surrounding fields is considered a cost-effective practice to enhance ecosystem resilience and agro-biodiversity. The aim of this research was to assess the effects of native hayseed mixtures on plant and microarthropod communities in an agricultural area of Northern Italy. Three different experimental treatments were set up. The first was a control (C) (i.e., non-seeded plots left to spontaneous vegetation succession after ploughing no deeper than 15 cm). The second, hayseed seeded (Hs) after ploughing no deeper than 15 cm. The third experimental treatment was hayseed overseeded (Ov) on the resident plant community after only a superficial harrowing. Ov plots exhibited the preeminent positive effects on the total productivity and quality of the grassland in terms of total vegetation cover, cover and richness of typical grassland species (i.e., Molinio-Arrhenatheretea species), and cover of legumes, grasses and perennial species. Moreover, Ov sites exhibited the highest abundance of microarthropod taxa and soil biological quality (QBS-ar) but only in spring, when the disturbance of ploughing negatively affected Hs and C plots. On the other hand, Hs sites showed a great reduction of invasive alien (i.e., Ambrosia artemisiifolia and Artemisia verlotiorum) and segetal weed species (i.e., Capsella bursa-pastoris and Spergula arvensis) in terms of cover. This study provides valuable indication on using hayseed mixtures to create grassland habitats as reservoir of native flora and soil biodiversity in agriculture areas.

The orthopterans of the rice agroecosystem in western Lomellina (Lombardy, Italy).

Rice fields represent a valuable surrogate habitat for many wetland species, playing an important role for biodiversity conservation in human-managed landscapes. Despite the fact that several taxonomic groups have been thoroughly investigated in this agroecosystem, little is known about the orthopteran fauna which lives in and around rice paddies, especially in Europe. In this paper, we provide a first description of the orthopteran assemblages hosted in the rice agroecosystems of northern Italy, trying to evaluate their conservation value through an analysis of species ecological traits (habitat specificity and dispersal capacity). During field samplings in summer 2016, we detected 25 orthopteran species. The 24% of the community was composed by habitat specialist species and the 56% of the sampled taxa was characterised by high dispersal capacities. Rice fields are an extremely dynamic ecosystem, characterised by the continuous succession of flooding and drying periods and conditioned by many other farming activities. Consequently, the orthopteran fauna in rice crops is mainly composed of species well adapted to sudden environmental changes. On the other hand, rice fields represent a particular biotope, providing a suitable habitat especially for hygrophilous species, which are otherwise restricted to scattered marsh areas. In order to preserve orthopteran diversity in rice agroecosystems, sustainable farming practices should be applied, especially by preserving and restoring marginal semi-natural habitats, by reducing grass management intensity on paddy banks and by discouraging rice cultivation in dry soils.

Combining habitat requirements of endemic bird species and other ecosystem services may synergistically enhance conservation efforts.

Biodiversity conservation and the optimisation of other ecosystem service delivery as a contribution to human well-being are often tackled as mutually alternative targets. Modern agriculture is a great challenge for the fulfilment of both. Here, we explore the potential benefits of integrating biodiversity conservation and the preservation of wider ecosystem services, considering the conservation of an endemic species (Moltoni's warbler Sylvia subalpina; Aves: Sylvidae) and soil erosion control (a final ecosystem service) in intensive vineyards in Italy. We modelled factors affecting warbler occurrence and abundance at 71 study plots by means of N-mixture models, and estimated soil erosion at the same plots by means of the Universal Soil Loss Equation. Shrub cover had positive effects on both warbler abundance and soil retention, whereas higher slopes promote warbler abundance as well as soil erosion. Creating shrub patches over sloping sites would be at the same time particularly suited for warblers and for soil retention. We simulated three alternative conservation strategies: exclusive focus on warbler conservation (1), exclusive focus on soil preservation (2), integration of the two targets (3). Strategies assumed the creation of 1.5-ha shrub patches over 5% of the total area covered by plots and targeted either at wildlife or soil conservation. The exclusive strategies would allow an increase of 105 individuals and the preservation of 783 tons ha-1year-1, respectively. Each individual strategy would ensure benefits for the other target corresponding to 61-64% of the above totals. The integrated strategy would allow for the achievement of 91-93% of the benefits (96 warblers and 729 tons ha-1year-1) of the individual strategies. The integration of the two approaches could provide important synergies, allowing to broaden the effects of conservation strategies, such as agri-environmental schemes that could be drawn from our results (and which are particularly urgent for intensive permanent crops).

Nestedness of habitat specialists within habitat generalists in a butterfly assemblage.

The habitat requirements of a species are the resources, conditions and space required for survival and reproduction. The habitat requirements of butterflies have been well studied, but the extent to which individuals within a species and between species utilise and share the habitat is poorly known.In a butterfly assemblage in northern Italy, we found that adults from 30 species avoid deciduous high-density forests and their ecotones, and they were positively related to open areas and their ecotones. Besides these common features, five groups of species can be discriminated in relation to a gradient from open area to forest, and species within groups were not equally specialised, as observed from a bipartite network analysis. In particular, some species appeared to be specialised and others appeared to be generalist, suggesting a nested pattern of resource use, rather than a clustered pattern in which each species uses a different subset of habitat types.The degree of variation in specialisation among species varied with the number of species falling in each group. Thus, an increased number of species, and thus possibly competition, is more likely to promote the co-occurrence of generalist and specialised species (nested patterns) rather than an increased niche segregation among species.Ascertaining how species overlap their habitat use at a local scale can be relevant for conservation purposes, because specialised populations are potentially more susceptible to network distortions.

Modelling the Distribution of Forest-Dependent Species in Human-Dominated Landscapes: Patterns for the Pine Marten in Intensively Cultivated Lowlands.

In recent years, the "forest-specialist" pine marten Martes martes has been reported to also occur also in largely fragmented, lowland landscapes of north-western Italy. The colonization of such an apparently unsuitable area provided the opportunity for investigating pine marten ecological requirements and predicting its potential south- and eastwards expansion. We collected available pine marten occurrence data in the flood plain of the River Po (N Italy) and relate them to 11 environmental variables by developing nine Species Distribution Models. To account for inter-model variability we used average ensemble predictions (EP). EP predicted a total of 482 suitable patches (8.31% of the total study area) for the pine marten. The main factors driving pine marten occurrence in the western River Po plain were the distance from watercourses and the distance from woods. EP suggested that the pine marten may further expand in the western lowland, whilst the negligible residual wood cover of large areas in the central and eastern plain makes the habitat unsuitable for the pine marten, except for some riparian corridors and the pine wood patches bordering the Adriatic coast. Based on our results, conservation strategies should seek to preserve remnant forest patches and enhance the functional connectivity provided by riparian corridors.

Saproxylic beetles of the Po plain woodlands, Italy.

Forest ecosystems play an important role for the conservation of biodiversity, and for the protection of ecological processes. The Po plain woodlands which once covered the whole Plain, today are reduced in isolated highly threatened remnants by modern intensive agriculture. These close to natural floodplain forests are one of the most scarce and endangered ecosystems in Europe. Saproxylic species represent a major part of biodiversity of woodlands. The saproxylic insects are considered one of the most reliable bio-indicators of high-quality mature woodlands and have a very important role in regard to the protection and monitoring of forest biodiversity due to their highly specific living environments. As a result of the dramatic reduction of mature forests and the decreased availability of deadwood most of the saproxylic communities are greatly diminishing. The study was conducted in the Ticino Valley Regional Park and the aim is to contribute to the expansion of knowledge on the saproxylic beetles of Lombardy. We investigated 6 sampling sites belonging to alluvial and riparian mixed forests. For each forest we selected 12 trees. For beetles' collection we used two different traps: Eclector Traps and Trunk Window Traps (total of 72 traps and 864 samples collected). We determined 4.387 beetles from 87 saproxylic species belonging to 21 families. Of these species 51 were not included in the previous checklist of the Park. By comparing the two different techniques used for catching saproxylic beetles, we found a significantly high difference in species richness between Window Traps (WT) and Eclector Traps (ET) with a higher number of species captured in the Window Traps. However, the combined use of two different types of traps significantly expanded the spectrum of insects captured Among the species reported as Least Concern in the IUCN Red List, we found interesting species such as the ElateridaeCalambusbipustulats, the EucnemidaeMelasisbuprestoides and the following species never previously found in the Park: CerambycidaeXylotrechusrusticus, the CetoniidaeValgushemipterus, the ElateridaeLaconpunctatus, the MycetophagidaeMycetophaguspiceus, Litargusconnexus. Although we didn't find species listed in the Annexes of the EU Habitat Directive, some of the species found are locally threatened because of their rarity, local distribution, and strong linkage to old forests. Among these species there are the BothrideridaeBothrideresbipunctatus, the CerambycidaePrionuscoriarius and Xylotrechusrusticus, the DryophthoridaeDryophthoruscorticalis, the EucnemidaeNematodesfilum (with only 1 individual captured in Alnus unmanged forest), the HisteridaeAeletesatomarius and Paromalusflavicornis, the LaemophloeidaeCryptolestesduplicatus, the LatridiidaeEnicmusrugosus and Latridiushirtus, the MycetophagidaeMycetophaguspiceus, and the ZopheridaeColydiumelongatum and Pycnomerusterebrans.

Ground beetles (Coleoptera: Carabidae) of rice field banks and restored habitats in an agricultural area of the Po Plain (Lombardy, Italy).

An entomological investigation was carried out in an agricultural area, mainly rice fields, of the Po river plain, located in the municipalities of Lacchiarella (MI) and Giussago (PV) (Lombardy, Italy). In 2009 and 2010, ground beetles (Coleoptera: Carabidae) were sampled along rice field banks and in restored habitats, by means of pitfall traps. The area appeared as species-rich, compared to other anthropogenic habitats in the Po river pain. Most of the collected Carabids were species with a wide distribution in the Paleartic region, eurytopic and common in European agroecosystems. The assemblages were dominated by small-medium, macropterous species, with summer larvae. No endemic species were found. Species with southern distribution, rarely found north of the Po river, were also sampled. Amaralittorea is recorded for the first time in Italy.

The 50 most important questions relating to the maintenance and restoration of an ecological continuum in the European Alps.

The European Alps harbour a unique and species-rich biodiversity, which is increasingly impacted by habitat fragmentation through land-use changes, urbanization and expanding transport infrastructure. In this study, we identified the 50 most important questions relating to the maintenance and restoration of an ecological continuum - the connectedness of ecological processes across many scales including trophic relationship and disturbance processes and hydro-ecological flows in the European Alps. We initiated and implemented a trans-national priority setting exercise, inviting 48 institutions including researchers, conservation practitioners, NGOs, policymakers and administrators from the Alpine region. The exercise was composed of an initial call for pertinent questions, a first online evaluation of the received questions and a final discussion and selection process during a joint workshop. The participating institutions generated 484 initial questions, which were condensed to the 50 most important questions by 16 workshop participants. We suggest new approaches in tackling the issue of an ecological continuum in the Alps by analysing and classifying the characteristics of the resulting questions in a non-prioritized form as well as in a visual conceptualisation of the inter-dependencies among these questions. This priority setting exercise will support research and funding institutions in channelling their capacities and resources towards questions that need to be urgently addressed in order to facilitate significant progress in biodiversity conservation in the European Alps.