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Context: Conservation of endangered species necessitates an in-depth understanding of their ecological requirements. Particularly in landscape ecology, the behavioural tendencies of threatened butterfly species in Gotland, a biodiversity-rich island in the Baltic Sea, become crucial. Objectives: The primary aim of this study was to elucidate the movement patterns of three threatened butterfly species—Euphydryas aurinia, Parnassius apollo, and Phengaris arion—in Gotland and to identify the influence of specific land characteristics on these patterns. Methods: Our study, conducted from 2017 to 2020 across 60 km2 in Gotland, involved detailed capture-mark-recapture (CMR) efforts of 29,584 captures including 16,223 unique butterflies. We investigate the departure and arrival events of butterflies, specifically focusing on the associations between movements when individuals leave or enter a hectare grid different from their previously recorded location and key landscape features: open vegetated land, ground moisture, and forest cover. We model landscape features to examine the interplay between these and butterfly movement patterns, providing insights into preferred landscape features and conservation strategies. Results: Among the 4821 arrivals and 5083 departures documented, the species exhibited differential responses to the evaluated habitat features. Both E. aurinia and P. apollo displayed a positive density-dependent dispersal, while P. arion's movements were not significantly associated with any of the examined habitat features. Landscape properties like open vegetated land and ground moisture index statistically influenced the likelihood of arrival and departure. Conclusions: The study accentuates the relationship between land cover and the behavioural tendencies of the subject butterfly species. It has broader implications for the targeted habitat management strategies that would benefit threatened butterfly populations in Gotland. [ABSTRACT FROM AUTHOR]

The dynamic interplay between anthropogenic activities and biodiversity conservation necessitates a nuanced understanding of habitat change, especially in contexts marked by transitions from grasslands to forested areas. This investigation utilised three threatened butterfly species—the Marsh Fritillary, Apollo, and Large Blue—as models to explore how grassland associated species respond to altered environmental conditions. The methodology encompassed extensive field surveys and statistical analyses with ecological niche modelling to determine their current and future distributions on the Island of Gotland. The species were surveyed under distinct years from 2017 to 2020 in a total of 3333 hectares in a 6000 hectare area—the Marsh Fritillary in 2017 (1232 hectares), Apollo in 2019 (2346 hectares), and Large Blue in 2020 (2256 hectares). Results revealed that the estimated current extents of suitable habitats were 49,104 hectares for the Marsh Fritillary (15.6% of the island), 45,646 hectares for Apollo (14.5%), and 33,089 hectares for Large Blue (10.5%). In general, increased forest and shrub cover and decreased heterogeneity negatively affected butterfly occupancy, but each species exhibited unique habitat preferences. The predictive modelling demonstrated that continued succession would reduce the amount of habitats predicted to be suitable and generated alarming forecasts—a twofold increase in forest and shrub cover suggests habitat declines of 41%, 47%, and 65% for the Marsh Fritillary, Apollo, and Large Blue, respectively. Given these findings, proactive measures are imperative for strategically managing these habitats to preserve landscape heterogeneity and accommodate diverse ecological needs. This study is important to conservation management providing, crucial insights amid anthropogenic and ecological changes. [ABSTRACT FROM AUTHOR]

While some species rapidly decline, compromising vital ecosystem services, others are stable or even increasing in abundance. We studied shifts in species richness and abundance of moths over five decades in Central Sweden and examined whether and how changes were associated with phenotypic traits. We combined information from captures in a light trap in historical time (the 1970s) and contemporarily (2019) with provincial colonisation records. Both community species richness and the abundance of moths increased between the time periods. A large fraction (38%) of the 410 species were not present in both periods, 101 species had colonised the area (an estimated influx of about 2.5 new species per year), and 51 species had disappeared (an estimated local extinction rate of about 1.16 species per year). Abundance increased with an increasing number of host plants and with increasing colour pattern variation. The composition of the community shifted towards species characterised by smaller wingspan and larger ranges. The functional trait variability of the moth community was homogenised from the historical to the contemporary period, in line with reports from other species communities in modern landscapes. However, our finding of a concomitant increase in species richness and total abundance differs from the results of many recent studies of insect communities in other geographic regions. Implication for insect conservation: We conclude that the entire boreal moth fauna is undergoing a substantial biogeographical shift, changing to the moth species historically occurring at more southern latitudes. The alterations in species composition, overall abundance, and community-wide trait distribution described here may cascade up and down in the ecosystem because moths are important pollinators, herbivores, and prey. [ABSTRACT FROM AUTHOR]

We used observational data collected during a mark-recapture study that generated a total of 7503 captures of 6108 unique individuals representing three endangered butterfly species to quantify inter-and intraindividual variation in temperature utilization and examine how activity patterns vary according to season, time of day, and ambient temperature. The Marsh Fritillary, the Apollo, and the Large Blue differed in utilized temperatures and phenology. Their daily activity patterns responded differently to temperature, in part depending on whether they were active in the beginning, middle or end of the season, in part reflecting interindividual variation and intraindividual flexibility, and in part owing to differences in ecology, morphology, and colouration. Activity temperatures varied over the season, and the Apollo and the Large Blue were primarily active at the highest available ambient temperatures (on the warmest days and during the warmest part of the day). The Marsh Fritillary was active early in the season and decreased activity during the highest temperatures. The relationship between individual lifespan and the average temperature was qualitatively different in the three species pointing to species-specific selection. Lifespan increased with an increasing range of utilized temperatures in all species, possibly reflecting that intra-individual flexibility comes with a general survival benefit. [ABSTRACT FROM AUTHOR]

Pesticide use in developing countries increases rapidly. In many regions, we miss knowledge of how frequently pesticides are applied and which active ingredients are used. We present a new cost-efficient and rapid assessment method of recording pesticides diversity in rice-dominated landscapes and present some evidence of the misuse of active ingredients in our study regions. We investigated 17 rice fields in two regions of Northern Vietnam in 2014 and 2015. At each region, we explore the abundance of pesticides used with three methods including (1) the novel approach of collecting pesticide packages close to our target rice fields, (2) observations of farmers spraying pesticides in the surrounding and (3) interviewing local farmers. By collecting pesticide packages, we found 811 packages containing 74 different active ingredients. On average, 19 active ingredients (ranging from four to 40 active ingredients) were applied with an average content of 275.3 g of active ingredients per site. Insecticide packages (39%) were most abundant followed by those of fungicides (31%), herbicides (16%) and other active ingredients (14%). On all sites, active ingredients banned in the European Union were applied by the farmers. Collecting pesticide packages proved to be an efficient and rapidly implemented method to obtain some baseline information about pesticide application (for Northern Vietnam). We suspect that improved agricultural extension services could contribute to good agricultural practices in pest management. Generally, better information and education for local farmers for appropriate use of pesticides seem a necessity. [ABSTRACT FROM AUTHOR]

Bees are important pollinators of wild plants and crops, but little is known about bee habitat requirements and pollinator management in tropical mountainous agricultural regions. Here, smallholder farmers produce fruits and vegetables in homegardens that depend upon or benefit from bee pollination. We hypothesized that abundance and richness of wild and domesticated bees and the complexity of plant-pollinator interactions are higher in homegardens surrounded by woody habitats than in homegardens found farther from woodlands. Bees were sampled in 20 homegardens in the rice terraces of the Philippine Cordilleras. We used linear mixed effect models to analyse effects of woody habitats around homegardens on bee richness and abundance. Based on pooled observations for each garden category, we built pollinator-plant interactions networks to illustrate shifts in interaction frequencies. We recorded 354 bee individuals of 13 wild and one domesticated bee species (Apis cerana). Wild bee richness was significantly higher in homegardens surrounded by woody habitats. Bee abundance increased significantly with increasing flower cover. Wild bees visited cultivated plants significantly more often than domesticated bees. Six vegetable species and 76% of all flower visits on cultivated plants in total were performed by wild bees and three plant species and 24% by domesticated bees. Pollinator-plant networks were more complex in homegardens surrounded by woody habitats. We conclude that woody habitats increase abundance and richness of wild and domesticated bees. Increasing availability of floral resources also promotes bee abundance. In order to promote pollination services in the landscape mosaic of smallholder rice farms, woody habitats and forest fragments together with numerous floral resources should be protected and restored. [ABSTRACT FROM AUTHOR]

Human pressures on the environment are changing spatially and temporally, with profound implications for the planet's biodiversity. Butterflies are important indicators for environmental change and are a suitable group to detect areas of high conservation concern and prioritize conservation efforts. To obtain data to support urgently-needed conservation measures, we surveyed the butterfly fauna in a mountainous region of northern Vietnam, using transect counts over 8 months (121 survey days) from June 2014 to April 2015. In total, we recorded >26,000 butterflies belonging to 231 species, including at least two species new to Vietnam, three red-listed and protected species listed by CITES. Most species were rare: we recorded members of 100 species ≤5 times and 52 species just once. Males dominated the sample, accounting for 81% of all observed butterflies and all members of 84 observed species. Species richness and abundance were highest in July, and there were surprisingly large changes in species composition between months. Species richness curves reached saturation, indicating that we detected most species present in the area, except for members of two families (Lycaenidae and Hesperiidae). Our results highlight the importance of thorough studies using standardized methods, capable of detecting most species in an area, over a whole season. There are urgent needs to integrate butterflies into conservation programs and use their potential as indicator species of habitat degradation and land use intensity. [ABSTRACT FROM AUTHOR]

Predicted climate change implies warmer weather and a higher frequency of extreme weather situations. The consequences of the warm July in 2003 was investigated in contrast to the cold July in 2004 in southern Sweden with focus on the dispersal rate of two species of burnet moths (Zygaenidae). During an extensive mark-release-recapture program in metapopulations of burnet moths substantial differences in inter habitat patch dispersal rates were observed. For two species of Zygaena it was 2.14 and 2.18 times higher during the warm year. Measured patch dispersal rate significantly declined towards the edges of the large study-area, suggesting that individuals disperse outside the study-area. No significant differences in dispersal rates were found between the two species studied. The dispersal rates were similar for both females and males, and no density dependent effects on dispersal or effects of amount of nectar rich flowers were found. Dispersal events appeared as distinct movements, often reaching several kilometres. We conclude that dispersal depend on climatic conditions. Exceptionally warm years may be especially important for survival of certain species in metapopulation systems and this may be crucial for the survival of populations during scenarios of climate change. [ABSTRACT FROM AUTHOR]

The Large Copper ( Lycaena dispar) has been extensively studied due to its high conservation priority. The species has declined severely in North-West Europe, but is currently expanding in Central and North-East Europe. In this study, we investigated egg deposition patterns at three different spatial scales (site, plant, and leaf level) for L. dispar at 23 sites within the municipality of Vienna (Austria). In one season, a total of 2,457 eggs were counted on six Rumex species, of which two ( R. stenophyllus, R. patientia) represent novel host plant records. Rumex crispus harboured 87.6% of all egg counts and was significantly preferred (4.4 eggs per plant) over the second-ranked R. obtusifolius for oviposition (1.1 eggs per plant). At the habitat scale, eggs were observed at all study sites. Egg numbers per site were equal across landscape zones, including stretches of waste land in urban habitats, except for lower egg numbers on meadows at the margin of the Vienna forest. Mowing was negatively related to the number of eggs found on all three studied scales. We conclude that L. dispar eggs are easier to find compared to adult butterflies, the butterfly can utilize more host plant species than what was previously known, and that mowing has a strong negative influence on the local butterfly populations. Urban wastelands provide important habitats, in which the species can sustain substantial population densities which are in comparison to those in the countryside. Conservation action should focus on applying less intensive rotational mowing, preferably involving mowing of suitable sites every 2 years. [ABSTRACT FROM AUTHOR]

Knowing how species' traits relate to processes that underlie occupancy patterns such as colonisation and population persistence, is important for our understanding of how species survive in fragmented and changing landscapes. We used automatic UV light-traps to sample noctuid moths on two remote islands, and compared traits of island occupants with those of a species pool from mainland southeast Sweden. Widely distributed species, generalist species, species with a long adult activity period and species active late in the summer had higher probability of occupancy on the remote islands. The results were consistent between islands. The traits of host plant specificity and species with an adult activity period during late summer remained robust and were statistically significant after controlling for any possible phylogenetic bias. This indicates that species exhibiting those traits survive better when habitat and climate changes. It is crucial to include our results in; (1) conservation planning, e.g. when devising conservation measures in fragmented landscapes; (2) for predictions of future occupancy patterns; and (3) ecosystem impact assessments, e.g. the importance of moths as pollinators, herbivores and being the functional link between parasitoids, plants, consumers and predators. [ABSTRACT FROM AUTHOR]

Climate change is occurring more rapidly in the Arctic than elsewhere, and is predicted to have a large impact on biodiversity, since entire cold-adapted ecosystems are likely to disappear. Here, we highlight changes in the insect species richness and community composition of wild bees, butterflies and moths over 60 years in an area situated above the tree limit (Padjelanta National Park) in northern Sweden. Although there were changes in habitat availability, indicated by a significant decrease in the area of a glacier (from 22 km in 1898 to 7.5 km in 2009), and an increase in the area of birch forest in the National Park, we nevertheless found relatively moderate changes in the insect communities. Indeed, the observed number of species increased from 52 in 1944 to 64 in 2008. Remarkably, the mean number of butterflies and moths per site, but not wild bee species, increased significantly. Among the species that were recorded in both periods, the average altitude of 17 species had shifted downhill, 12 shifted uphill, and the altitude of the remaining 17 had not changed. While alterations in community composition were greater at the highest altitudes, changes in the insect community were smaller than expected, indeed much smaller than those reported from agricultural landscapes in North-West Europe. Interestingly, our results suggest that lower alpine altitudes (600-800 m a.s.l.) have become colonized by southern species, but also that high alpine areas (above 1,000 m a.s.l.) have recently become colonized by high alpine species previously absent from these sites, likely as a result of increasing habitat availability. We conclude that wild bee, butterfly, and moth communities in Arctic areas in northern Sweden are in flux, as a result of climate change and suggest that increased attention must be given to conservation planning in cold areas. In addition, we propose that monitoring programs should be established, because more pronounced climate-driven changes can be expected in the future. [ABSTRACT FROM AUTHOR]

Cold-adapted ecosystems are often considered to be stable, species poor, and well protected. However, such ecosystems have been identified as being especially sensitive to threats from global warming. Despite this, recent studies have found low proportions of Red Listed species in these systems. In this study we explored the number of alpine species (dependent on alpine habitats for their survival) and their Red List status in Sweden. We determined the proportion of Red Listed species and explored discrepancies among different groups of organisms in terms of the proportion of Red Listed species and the criteria used for Red Listing. We found a total of 389 alpine species in twelve analyzed species groups. The overall proportion of Red Listed species was 29%, with 15% regarded as threatened. There were substantial differences among taxonomic groups with respect to the proportion of Red Listed species. Among mammals 75% of the species are Red Listed, along with 63% of butterflies and 50% of birds. In addition the single alpine dragonfly species and all three alpine stinging wasp species are also Red Listed. Although beetles, bumblebees and grasshoppers are represented by a total of 17 alpine species, none are Red Listed. In contrast to previous studies, our results show that the proportion of Red Listed species is high in alpine environments, indicating that ecosystems found above the tree line are indeed threatened. No species in Sweden have been Red Listed on the basis of the IUCN criterion E (unfavorable quantitative analysis), this is surprising since entire cold-adapted ecosystems are likely to disappear in the future. We highlight the need for a better and more coordinated application of the IUCN criteria, as well as a more stringent strategy to assess the extinction risks for alpine species, thus maintaining reliable Red Lists. [ABSTRACT FROM AUTHOR]

The landscape matrix is suggested to influence the effect of habitat fragmentation on species richness, but the generality of this prediction has not been tested. Here, we used data from 10 independent studies on butterfly species richness, where the matrix surrounding grassland patches was dominated by either forest or arable land to test if matrix land use influenced the response of species richness to patch area and connectivity. To account for the possibility that some of the observed species use the matrix as their main or complementary habitat, we analysed the effects on total species richness and on the richness of grassland specialist and non-specialist (generalists and specialists on other habitat types) butterflies separately. Specialists and non-specialists were defined separately for each dataset. Total species richness and the richness of grassland specialist butterflies were positively related to patch area and forest cover in the matrix, and negatively to patch isolation. The strength of the species-area relationship was modified by matrix land use and had a slope that decreased with increasing forest cover in the matrix. Potential mechanisms for the weaker effect of grassland fragmentation in forest-dominated landscapes are (1) that the forest matrix is more heterogeneous and contains more resources, (2) that small grassland patches in a matrix dominated by arable land suffer more from negative edge effects or (3) that the arable matrix constitutes a stronger barrier to dispersal between populations. Regardless of the mechanisms, our results show that there are general effects of matrix land use across landscapes and regions, and that landscape management that increases matrix quality can be a complement to habitat restoration and re-creation in fragmented landscapes. [ABSTRACT FROM AUTHOR]

Andrena hattorfiana is a rare solitary bee which has declined during the last decades throughout western Europe. It is specialised to forage pollen from plants of the family Dipsacaceae. Knowledge of distribution, dispersal propensity, and local population sizes is essential for successful conservation of A. hattorfiana. The investigated local bee populations ( n = 78) were dominated by small local populations and 60% were smaller than 10 female individuals and 80% were smaller than 50 female individuals. The area of the median occupied habitat patch was 1.25 hectare and harboured 7 female bees. Mark-release-recapture studies of female A. hattorfiana revealed a sedentary behaviour. Among pollen-foraging female bees the average registered distance moved was 46 m. The patch emigration rate was about 2%, with an observed maximum colonization distance of 900 m. Only 10% of the individuals crossed areas without the pollen plant within grassland patches, such as unpaved roads, stone walls and small tree-stands, even if these areas were less than 10 m wide. This study shows that solitary bees can occur in local populations of extremely small size and they have a sedentary behaviour. These are features that usually increase the risk of local population extinction. [ABSTRACT FROM AUTHOR]

An extensive follow-up study of day- and night-active Macrolepidoptera was performed during 2004 at the Kullaberg Nature Reserve located in the south-western part of Sweden. Butterflies were surveyed in an area of 100 km2 and night-active moths were trapped in the core area of the reserve. Macrolepidopteran species resident in the area in the 1950s were compared with species resident in the area in 2004. As much as 159 of 597 species (27%) resident in the area in 1950s were not found at all in 2004 and 22 species (4%) had colonised the area. Butterflies exhibited a disastrous decline with a loss of 45% of the fauna, and day-active species had declined more than night-active species had. Species distribution pattern and species characteristics were used to predict the probability that a species had become extinct or colonised the area. Species limited to one or a few food plants, with a short flight-period or restricted to non-forest habitats were all associated with a high extinction risk. Species occurring in fewer European countries and recorded from few provinces in Sweden were all associated with a higher extinction risk compared with ubiquitous species. For expanding species (colonisers), the best predictor was their distribution area in Sweden and colonising species were more likely to be limited to a few provinces in the southernmost part of Sweden. Species extinct from Kullaberg also have decreased in Finland and species that had colonised Kullaberg also have increased in Finland, while the species with no change in Kullaberg are also relatively constant in Finland. Indeed, the macrolepidopteran fauna was severely reduced in the last 50 years and almost 70% of the habitat specialists were lost. For red-listed species the situation was found to be alarming. Almost 70% of red-listed species, resident in the area in the 1950s, was not found in 2004. This study highlights that species composition changes rapidly even in protected nature reserves and that similar changes in the macrolepidopteran fauna seem to occur over large areas. [ABSTRACT FROM AUTHOR]

Range shifts have been documented in many organisms, and climate change has been implicated as a contributing driver of latitudinal and altitudinal range modifications. However, little is known about what species trait(s) allow for faster environmental tracking and improved capacity for distribution expansions. We used data for 416 species of moths, and show that range limits in Sweden have shifted to the north by on average 52.4 km per decade between 1973 and 2014. When also including non-expanding species, average expansion rate was 23.2 km per decade. The rate of boundary shifts increased with increasing levels of inter-individual variation in colour patterns and decreased with increasing latitude. The association with colour patterns indicate that variation in this functionally important trait enables species to cope with novel and changing conditions. Northern range limits also increased with average abundance and decreased with increasing year-to-year abundance fluctuations, implicating production of dispersers as a driver of range dynamics. Studies of terrestrial animals show that rates of poleward shifts differ between taxonomic groups, increase over time, and depend on study duration and latitude. Knowledge of how distribution shifts change with time, location, and species characteristics may improve projections of responses to climate change and aid the protection of biodiversity. [ABSTRACT FROM AUTHOR]