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The non-native invasive box-tree moth Cydalima perspectalis causes severe damage to ornamental box trees (Buxus spp.) and natural boxwood stands. So far, no promising natural enemy of C. perspectalis has been discovered in Europe. Many garden owners would like to protect their box trees from C. perspectalis without the use of insecticides, which also harm other arthropod species. In a controlled experiment under natural conditions, we tested whether box trees covered with a net during the flight period of C. perspectalis are as well protected against the moth as trees treated with a bioinsecticide. After 1 year, the box trees covered with a net during the moths' flight activity (monitored by light traps) showed no damage by larvae (average loss of leaves 0%), as did box trees regularly treated with a bioinsecticide (control group 1). In contrast, box trees with no protection (untreated box trees; control group 2) lost 97.7% of their leaves due to larval feeding. In a second experiment, we investigated whether defoliated box trees can recover when covered with a net during the flight period of the moth. Protected by the net, the emerging new leaves were not attacked by C. perspectalis. After 1.5 years, the trees had 24% of their original foliage again. Our study demonstrates that temporarily covering box trees with a net protects them against damage by C. perspectalis in an effective way. [ABSTRACT FROM AUTHOR]

The functioning of forest ecosystems depends on the taxonomic and ecological diversity of soil fungi. Urbanization is increasing worldwide and is regarded as a key driver of environmental change altering local species assemblages in urban forest. We investigated whether the degree of urbanization and local forest characteristics affect the soil fungal community in 20 beech forests located along a rural–urban gradient in the city of Basel and its suburbs (Switzerland). We analyzed their soil fungal communities by DNA metabarcoding of the rDNA ITS2 region and related these data to local forest vegetation characteristics and soil properties. The number of fungal OTUs in the 20 forests examined ranged from 170 to 303. Richness, diversity and evenness of fungal communities were all significantly affected by the degree of urbanization, but in different ways. Soil fungal richness was highest in forests in areas with a low degree of urbanization and lowest in forests in rural areas. In contrast, the fungal community diversity increased with the increasing degree of urbanization. Different fungal phyla and fungal guilds showed distinct patterns in their relative abundance along the rural–urban gradient. The degree of urbanization reduced the relative abundance of symbiotrophic fungi, but increased that of saprotrophic and pathotrophic fungi. Our results show that urbanization changes soil fungal community, which in turn can lead to alterations in forest ecosystems. [ABSTRACT FROM AUTHOR]

Rock-dwelling land snails, feeding on algae and lichens that grow on stone surfaces, may influence the structure and function of these ecosystems. Yet, little is known about the life history of rock-dwelling snails. We performed a 30-month mark-release-resight study in four populations of Chondrina clienta (Westerlund, 1883) inhabiting vertical walls of abandoned limestone quarries on the Baltic island of Oland, Sweden, to assess growth rate and survival of juvenile snails and determine age at maturity. We marked 800 individuals ranging in shell height from 1.4 to 4.9 mm, released them in their original habitat, and remeasured their shell height at intervals of 6 months. Shell growth of juvenile C. clienta was affected by the site (quarry wall) and the size of the individual, being highest in medium-sized snails. Shell growth occurred during both summer and winter. Annual apparent survival rates of C. clienta were size-dependent and ranged from 58.6% to 96.3%. Sexual maturity was reached at an age of 5 years, which is later than in most large snail species. Our study extends current knowledge on life history of land snails to a rarely studied group dwelling on rock surfaces. Key words: age at maturity, annual survival rate, Chondrina clienta, individual growth, life history, rock-dwelling land snail, terrestrial gastropod. Si les escargots terrestres vivant sur la roche et se nourrissant d'algues et de lichens sur les surfaces rocheuses peuvent influencer la structure et la fonction de ces ecosystemes, les connaissances sur le cycle biologique de ces animaux sont pourtant tres limitees. Nous avons mene une etude consistant a marquer, relacher, puis reexaminer des individus sur une periode de 30 mois dans quatre populations de Chondrina clienta (Westerlund, 1883) vivant sur les parois verticales de carrieres de calcaire abandonnees dans l'ile balte d'Oland (Suede), afin d'evaluer le taux de croissance et la survie d'escargots juveniles et de determiner leur age a la maturite. Nous avons marque 800 individus dont les hauteurs de la coquille allaient de 1,4 a 4,9 mm, les avons ensuite relaches dans leur habitat d'origine, puis remesure la hauteur de leur coquille tous les 6 mois. La croissance de la coquille de C. clienta juveniles variait selon le site (paroi de la carriere) et la taille de l'individu, le taux de croissance etant le plus eleve pour les escargots de taille moyenne. La croissance de la coquille s'effectuait tant l'ete que l'hiver. Les taux annuels de survie apparente de C. clienta dependaient de la taille et allaient de 58,6 % a 96,3 %. La maturite sexuelle etait atteinte a l'age de 5 ans, soit plus tard que pour la plupart des especes d'escargot de grande taille. Notre etude elargit les connaissances actuelles sur le cycle biologique des escargots terrestres a un groupe rarement etudie qui vit sur les surfaces rocheuses. [Traduit par la Redaction] Mots-cles : age a la maturite, taux de survie annuel, Chondrina clienta, croissance individuelle, cycle biologique, escargot terrestre vivant sur la roche, gasteropode terrestre., Introduction Growth is an important life-history process, influencing a range of later fitness-related traits such as age and size at maturity and total reproductive output (Stearns 1992; Charnov 2004; English [...]

Horticultural trade is considered the most important pathway for the introduction of non-native plant species. Numerous horticultural plants are spreading from private gardens and public green space into natural habitats and have the potential to alter native biodiversity and ecosystem functioning. We assessed the invasiveness of the horticultural plant Lamium galeobdolon subsp. argentatum. We documented its spread in semi-natural habitats in the surroundings of Basel, Switzerland, over the past decades. We compared the performance of L. g. argentatum with that of the native subspecies Lamium galeobdolon galeobdolon based on surveys in forests and a pot experiment under standardized conditions. We also assessed whether the two subspecies differentially affect native forest vegetation and various physical, chemical and biological soil properties. The horticultural L. g. argentatum has tripled its occurrence in forests in the region of Basel in the last four decades. Lamium g. argentatum had both a higher growth rate and regeneration capacity than the native subspecies. Furthermore, L. g. argentatum reduced native plant species richness and changed the species composition of the ground vegetation, in addition to altering several soil properties in deciduous forests. Lamium g. argentatum should therefore be considered an invasive taxon. [ABSTRACT FROM AUTHOR]

We synthesize findings from a 7-year fragmentation experiment in species-rich, nutrient-poor, dry calcareous grasslands in the north-western Jura mountains, Switzerland. We used a standardized approach with 48 fragments (0.25–20.25 m2) and corresponding control plots in three sites. The 5-m-wide isolation area around the fragments was maintained by frequent mowing. Fragments experienced various ecological changes, e.g., plant biomass increased along fragment edges. We examined fragmentation effects on species richness and composition, abundance, genetic diversity, functional diversity, species traits and species interactions (pollination, herbivory, parasitism, disease) in a wide array of invertebrate (gastropods, spiders, woodlice, various insect groups) and plant taxa. Responses to fragmentation differed between taxonomical groups and species. While species richness and individual density were lower in fragments in some groups, the opposite was true for other groups. Fragmentation effects were most pronounced on species interactions; however, some effects only occurred with a delay. For example, fragmentation influenced foraging patterns of bumblebees, affecting pollination, which in turn resulted in a decreased outcrossing frequency and reduced genetic diversity in a focal plant species. We highlight key findings of the experiment and emphasize their implications for grassland conservation. [ABSTRACT FROM AUTHOR]

Knowledge of patterns of genetic diversity in populations of threatened species is vital for their effective conservation. However, destructive sampling should be avoided in threatened species so as not to additionally increase the risk of local population extinction. We exclusively used beetle remains and beetles collected after death to analyze local and regional patterns of genetic variation in the endangered flightless longhorn beetle Iberodorcadion fuliginator in the border region of Switzerland, France and Germany, in grassland remnants. We extracted DNA from the beetles' remains and genotyped 243 individuals at 6 microsatellite loci. We found moderate genetic differentiation between populations, each belonging to one of two metapopulations situated on either side of the river Rhine, but distinct genetic differentiation between populations across metapopulation. The genetic distance between populations was correlated with the geographic distance between the sites sampled. Genetic structure analysis inferred the presence of two genetic clusters. The populations in the Alsace (France) represent one cluster, together with the Swiss populations near Basel, which is separated by the river Rhine from the cluster composed of the populations in southwestern Germany. Thus, the historical separation by the river Rhine surpasses more recent effects of human-induced habitat fragmentation on the genetic differentiation in I. fuliginator. [ABSTRACT FROM AUTHOR]

Carabid beetles of the tribe Licinini use their asymmetric mandibles to open the shells of land snails. Prey handling of large snails has been described in a few Licinini species. We observed for the first time how a male of Licinus depressus (Paykull, 1790) opens the shells of small prey snails (Chondrina arcadica (Reinhardt, 1881)) and eats their soft bodies. The beetle holds the conical snail shell with its forelegs and breaks the wall of the right-hand coiled shell. In doing so, the beetle rotates the shell counter-clockwise opening it stepwise along the dorsal part of the whorls towards the apex. After some bites, the beetle interrupts the opening process and begins to feed on the snail's soft tissue. Then the beetle continues to break up the shell, shortly after which there is another feeding phase. The alternating sequence of shell breaking and feeding ends after 2 to 2.5 whorls when the beetle can no longer hold the prey's remaining intact shell. We compare this previously unknown way of prey handling with the reported predatory behaviour in large snails by other Licinini species. Our observations confirm the high plasticity of predatory behaviour in Licinini beetles. [ABSTRACT FROM AUTHOR]