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Species monitoring plays an important role in determining whether conservation targets are being met. However, monitoring programs can be costly and logistically demanding. When site characteristics are strongly linked to species' status, managers may instead choose to monitor the site characteristics themselves as a surrogate of species status. In this study, we modelled the occupancy status and abundance of pond-breeding amphibians in a network of protected areas across Switzerland. We incorporated remotely-sensed data describing habitat within breeding sites in order to identify any characteristics which could act as monitoring surrogates for amphibian species' status. We found that connectivity between amphibian breeding sites was an important predictor of occupancy patterns for all species, but that abundance patterns were poorly predicted. Despite expectations that the habitat characteristics assessed from aerial images were important for the species studied, we found that these variables were rarely strong predictors of occupancy patterns. These results highlight the importance of caution in identifying species monitoring surrogates, and the need to explicitly demonstrate strong relationships between surrogates and state variables of interest before surrogates are used. [ABSTRACT FROM AUTHOR]

Abstract: Traditionally managed arable fields host a specialised flora adapted to regular disturbance through tillage. Agricultural intensification during the 20th century resulted in a pronounced biodiversity decline in European agroecosystems. Anthoceros agrestis and Phaeoceros carolinianus, both largely confined to cultivated land in Central Europe and the only representatives of hornworts in northern Switzerland, are examples of species that decreased in Central Europe during the last century. A repeated survey of 28 arable fields in the Swiss Plateau from 1989 to 1995 demonstrated that crop type and associated farming routines were critical in determining hornwort occurrences. During the 10 years following the completion of this survey, agri-environment schemes were introduced aiming at a more environmental-friendly agricultural production. We re-investigated the selected sites in 2005–2007 to examine whether these programmes favoured hornworts. We found a significant decrease of untilled autumn stubble-fields, which accounted for a decline of hornworts. High relative summer air humidity positively affected hornwort occurrence. Gametophytic populations of both taxa regenerated from the persistent diaspore bank after years of unfavourable conditions. To ensure the long-term persistence of hornworts in the Swiss Plateau, we recommend three alternative modifications of current Swiss agri-environment schemes to be implemented in cereal fields with known hornwort occurrences: (1) Tailored conservation headlands, (2) Autumn stubble-fields and (3) Field margin strips sown with arable flora but without crop plants. The proposed practices will promote other typically ephemeral arable bryophytes and seed plants and are likely to be advantageous also for other organisms, such as farmland birds. [Copyright &y& Elsevier]

Abstract: Many ecosystems of high conservation value have been shaped by human impacts over centuries. Today, traditional management of semi-natural habitats is a common conservation measure in Europe. However, despite traditional management, habitat remnants may still loose specialist species due to surrounding land-use change or atmospheric nitrogen deposition. To detect trends in species density (2-m2 plot scale) and habitat quality in calcareous fens in the pre-Alps of Switzerland, we surveyed 36 traditionally managed fens in 1995/97 and again in 2005/06 (five plots per fen). The fens occurred at three altitudinal levels (800–1000, 1000–1200, 1200–1400masl) and were either extensively grazed or mown once a year. Despite these traditional management regimes, species density of fen specialists and of all bryophytes decreased during this decade (vascular plant specialists: −9.4%, bryophyte specialists: −14.9%, all bryophytes: −5.7%). Management had no effect on the number of Red-List species and habitat specialists of vascular plants per plot. However, bryophyte species density was more strongly reduced in grazed fens. Species density of vascular plant generalists increased between the two surveys (+8.2%) but not of bryophytes. Among vascular plants, Red-List species decreased from 1.01 to 0.78 species per plot. Furthermore, between the two surveys aboveground plant biomass, mean plant-community indicator values for nutrients and species density of nutrient indicators increased, whereas mean plant indicator values for soil moisture, light and peat, and species density for peat indicators, decreased. We attribute these changes and the loss of specialist species over the past decade mainly to land-use change in the surrounding area and to nutrient inputs. Thus, despite traditional management, calcareous fens in the pre-Alps suffer from ongoing habitat deterioration and endangered plant species remain threatened. For their long-term protection, we suggest to reduce nutrient inputs and, where necessary, to restore hydrology and adjust grazing management. [Copyright &y& Elsevier]

• LiDAR data generally increases predictive performance of SDMs for woody species. • Especially light-demanding shrubs profit from including LiDAR data. • Opposing responses of light-demanding and shade-tolerant species along LiDAR data. • LiDAR data can decrease SDM-performance if it replaces important abiotic predictors. Modern multifunctional forest management can profit from high-quality information on the potential distribution of woody species generated by species distribution models (SDMs). Forest structure is an important factor in determining the distribution of woody species in forests, for example because it affects light conditions within forest stands. Remotely sensed data from light detection and ranging (LiDAR) can capture this three-dimensional structure of forests, leading to the expectation that LiDAR-derived data should enhance the predictive performance of SDMs. We test if and how LiDAR-derived data increases the predictive performance of SDMs for light-demanding and shade-tolerant shrub and tree species in Swiss forests. Our analyses suggest that LiDAR-derived data generally increases predictive performance of models. However, the response to including LiDAR-derived data varies depending on plant functional type: the increase in predictive performance is largest for light-demanding shrubs, reduced for light-demanding trees, and is lost for shade-tolerant species. We further find that shade-tolerant and light-demanding species show opposing responses along the LiDAR-derived predictors. Our results suggest that LiDAR-derived data indeed capture some aspects of light availability in forests, and that including LiDAR-derived predictors in SDMs should be considered for light-demanding shrubs, but may be of less use for trees (especially if shade-tolerant). We conclude that improving SDMs and resulting maps by including LiDAR-derived predictors potentially helps to ameliorate multifunctional, biodiversity-friendly forest stand management. [ABSTRACT FROM AUTHOR]

Biodiversity is currently experiencing an accelerated decline in terms of species and populations, mainly because of habitat loss. The designation of protected areas has therefore become essential for biodiversity conservation. However, compelling evidence for the long-term effectiveness of protected areas in maintaining species diversity is still scarce, especially for plant species, as analyses are often hampered by the limited availability of informative datasets from different time periods. Here we analysed the effectiveness of Swiss protected areas in maintaining vascular plant species typical for two habitat types, namely wetlands and dry grasslands. Furthermore, we tested whether the effect of protected areas on species persistence varies between low (<1000 m a.s.l.) and high elevations (≥1000 m a.s.l.). Data included several thousand historical occurrences, which were re-surveyed after 2002 at the scale of square kilometres. For each re-surveyed species, we identified the square kilometres where it had disappeared and those where it still occurred. We found that the amount of protected area within the square kilometres had a positive effect on the persistence of plant species in the studied habitat types. The effect, however, primarily occurred at low elevations, and even in square kilometres with the largest amount of protected area species declines were still observed. While protected areas at higher elevations are often embedded in a less intensively used matrix, which provides small habitat patches for threatened species, protected areas at lower elevations are often islands within an inhospitable, intensively managed matrix. This explains why protected areas at higher elevations are less important for the persistence of species within square kilometres studied here. Moreover, wetlands and dry grasslands have suffered from changes in land use or heavy exploitation during the past centuries, especially at lower elevations, with ongoing losses of species and populations occurring even within protected areas. Protected areas thus decelerate the landscape-scale loss of species but (apparently) do not fully stop it. [ABSTRACT FROM AUTHOR]

Abstract: Owing to their ability to accumulate heavy metals, mosses are especially suitable to monitor heavy metal airborne pollution. In Europe, starting in 1990 within the framework of UNECE ICP-Vegetation, the monitoring of background heavy metal deposition based on concentrations found in mosses were performed every five years in Switzerland, and, since 1995 also Bulgaria. Here we compare spatial and temporal trends of heavy metal depositions in these two countries and we assess to what extent a large scale European deposition model (MSCE-HM model) can be applied on these two countries. Highly significant differences in concentrations in mosses between the two countries were found for Cd, Cu, Ni, V, Cr, Fe, Pb. For Zn the differences were less clear, but still significant in 2000 and 2005. In Bulgaria, with the exception of Cr, heavy metal concentrations decreased between 1995 and 2005 (−14% to −29%). In Switzerland, Cd (−38%), Pb (−63%) and V (−23%) showed the strongest decrease between 1995 and 2005. For Fe, Ni and Zn no or only small concentration changes were found, whereas a considerable rise was recorded for Cr (+65%) and Cu (+15%). In comparison to median heavy metal concentrations in Europe, concentrations in Bulgaria were nearly always higher, while concentrations in Switzerland were always lower. For both Pb and Cd, relationships between modelled and moss-derived values for all of the years were highly significant, but explained variances were rather low. Overall, relationships between moss-derived depositions and modelled depositions were rather close to a 1:1-relationship in Switzerland. In Bulgaria the modelled depositions were considerably lower than the moss-derived depositions. Although deposition levels in Bulgaria also decreased, heavy metal concentrations in mosses were still high. In contrast to Switzerland, Bulgaria has a strong non-ferrous and ferrous heavy industry. New technologies must be implemented in order to reduce deposition levels in Bulgaria. Continuing the moss monitoring is crucial for future evaluations of environmental measures. [Copyright &y& Elsevier]

Extinction risk is not randomly distributed among species but depends on species traits, their relationship to climate and land use, and corresponding threats by global change. While knowledge of which factors influence extinction risk is increasingly available for some taxonomic groups, this is still largely lacking for bryophytes. Here, we used random forest models to study which biological and ecological traits and bioclimatic variables are important predictors for extinction risk in European bryophytes. We hypothesized that species with a high extinction risk have a short life span, low dispersal capacities, and are more likely specialists than generalists in terms of ecological traits and bioclimate. Overall, we found bioclimatic variables to be the most important predictors for extinction risk, most notably precipitation seasonality, and related ecological traits such as continentality and elevational range. Important biological traits were plant size, life strategy and sporophyte production. In general, species living at climatic extremes and/or those with a narrow environmental range are more likely to be threatened. In addition, small-sized species and/or species with low reproductive effort and/or larger spore size are more likely to be threatened. Our findings imply that climate change may become an important driver of bryophytes extinction risk and that biological and ecological traits will be most relevant for species in coping with future threats. [ABSTRACT FROM AUTHOR]

Reliable assessments of population status and trends underpin conservation management efforts but are complicated by the fact that imperfect detection is ubiquitous in monitoring data. We explore the most commonly considered variables believed to influence detection probabilities, quantifying how they influence detectability and assessing how occupancy rates are impacted when a variable is ignored. To do so, we used data from two multi-species amphibian monitoring programmes, collected by volunteers and professional surveyors. Our results suggest that although detection rates varied substantially in relation to commonly considered factors such as seasonal and annual effects, ignoring these factors in the analysis of monitoring data had negligible effect on estimated occupancy rates. Variation among surveyors in detection probabilities turned out to be most important. It was high and failing to account for it led to occupancy being underestimated. Importantly, we identified that heterogeneity among observers was as high for professional surveyors as for volunteers, highlighting that this issue is not restricted to citizen-science monitoring. Occupancy modelling has greatly improved the reliability of inference from species monitoring data, yet capturing the relevant sources of variation remains a challenge. Our results highlight that variation among surveyors is a key source of heterogeneity, and that this issue is just as pertinent to data collected by experts as by volunteers. Detection heterogeneity should be accounted for when analysing monitoring data. Furthermore, efforts to increase training of field crews and collecting data to quantify differences between observer abilities are important to avoid biased inference resulting from unmodelled observer differences. • Imperfect detection of species is common in species monitoring. • The detection process is influenced by many factors. • Detection heterogeneity among observers was very strong. • Unmodelled detection heterogeneity led to biased estimates of occupancy. [ABSTRACT FROM AUTHOR]

Old herbarium specimens and historical floristic data give insight into regional floras for given time periods. They often cover historical time periods for which few other data are available. Herbaria thus allow the study of changes of the flora of a region across time. Using a 150-year-old regional herbarium together with a historical publication, we investigated to which extent the flora of the Swiss canton of Schaffhausen has changed, which habitats were particularly affected by local extinction, what the environmental requirements of extinct plants were and whether conclusions about the respective drivers such as land use change can be drawn. A total of 987 species were historically recorded in the study region of which 154 are currently no longer reported and are regionally extinct. This means that about one species disappeared from the region every year. Species that are currently in a high category of endangerment on the Swiss Red List have declined markedly in the canton of Schaffhausen, showing that Red Lists well portrait the endangerment of species. Looking at plant strategies, the more stress-tolerant and less competitive plants have disappeared. In addition, wetland, pioneer, ruderal and mountain species as well as agricultural weeds and light-demanding species showed highest extinction rates. In contrast, forest species had a low extinction rate, and species from fertilized meadows showed no decline. Our evaluation of a regional herbarium helps to inform nature conservation about particularly endangered habitats and possible drivers of species decline. [ABSTRACT FROM AUTHOR]

• Swiss steppes harbour many specialist and threatened vascular plant species. • Total species richness peaks at intermediate productivity levels. • Productivity and wood cover reduce proportions of threatened and specialist species. • Low-intensity management and wood removal maintain low-productivity habitats. • Remote sensing-based warning system detects negative habitat changes. In Switzerland, steppe vegetation is restricted to inner alpine dry valleys in the West (Valais) and the East (Grisons). They harbour many specialist and threatened species. In 2011, a long-term program was established to monitor changes in Swiss habitats of national importance. Here, we studied patterns of vascular plant diversity in a subset of 148 steppe plots of 10 m2 from this program. Plots were either grazed or abandoned. On average, we found 23.3 species per plot. The proportion of steppe specialists and of threatened species out of the total species richness was 29.3% and 12.2%, respectively. The total number of species increased with elevation and peaked at intermediate productivity levels. In contrast, the proportion of threatened and steppe specialist species was generally negatively related to higher productivity and wood cover – two factors considered as indicators of habitat degradation. Abandonment vs. pasture had no effects on total species richness. Productivity was positively related to ecological indicator values for moisture, competition and ruderality, as well as the community mean traits of plant height and specific leaf area, but negatively with the indicator value for light. Similarly, wood cover was positively associated with higher ecological indicator values for productivity, moisture and competition, as well as the community mean trait of plant height, but negatively with the indicator value for light and ruderality. The negative response of threatened and steppe specialist vascular plant species to habitat degrading factors suggests their proportional richness to be a better indicator of habitat quality than the total species richness. We conclude that management regimes which guarantee low productivity and low wood cover and avoid intensification by fertilization and irrigation are essential for the conservation of steppe habitats. Beside periodic clearing of woody species, low-intensity grazing might prevent shrub encroachment. [ABSTRACT FROM AUTHOR]