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Forestry plantations have been established globally to meet timber demands, often leading to the conversion of natural to artificial forests. Forestry plantations may support natural elements of forest biodiversity, but understanding their role in the maintenance of biodiversity is a crucial question. We performed a meta-analysis of 48 studies to determine how forestry plantations relative to natural forests influence the species richness and abundance of three important coleopteran groups (i.e., ground beetles, rove beetles, and dung beetles), given their essential role in ecosystem functioning. We assessed whether beetle responses depended on taxonomic group, geographical location, native or exotic character of the planted tree species, and associated management characteristics (i.e., composition, size, age, and connectivity of the plantations). We found that forestry plantations negatively affected coleopteran species richness and abundance compared to natural forests. The negative impact was most severe in plantations with exotic tree species and located in tropical biomes. Species richness and abundance of beetles significantly increased with plantation age in native plantations but decreased in exotic ones. Also, small plantations close to native forest had higher beetle species richness and abundance than ones located far away from native forest. Stopping the conversion of natural forests to plantations, promoting the use of native tree species, and lengthening rotations are critical for allowing biodiversity recovery in forestry plantations, combined with a robust conservation strategy to protect threatened biodiversity and ecosystem functioning., Hungarian Basic Research Fund, Remedinal, Natural Environment Research Council, Ministerio de Ciencia e Innovación

Urbanization is increasing worldwide, fragmenting, isolating or destroying native habitats with a subsequent loss of biodiversity, structural and compositional changes of biotic communities and weakening of the functioning of biological processes and ecosystem services. In urban ecosystems, terrestrial mammals provide important functions and services, but we do not have a synthesis of the impacts of urbanization on terrestrial mammals. Terrestrial mammals are vulnerable to habitat loss and modification caused by urbanization, thus we hypothesised that the abundance and diversity of mammals would decrease as urbanization progresses. In addition, due to the declining number of predators and thus to decreasing predation pressure in urban habitats, we assumed that herbivore and omnivore mammals would gain dominance. To clarify the inconsistency of previous urbanization studies on terrestrial mammals, we synthetized and re-evaluated published results by meta-analysis. Based on 50 rural-urban comparisons, terrestrial mammals were not significantly more abundant or diverse in rural than urban habitats. This was not only found at the community level, but also at the level of taxonomic groups (carnivores, marsupials, rodents), feeding habit (carnivorous, herbivorous or omnivorous species) or at the level of their interactions. Our results suggest that the studied urban-dwelling mammal species are probably well adapted to environmental conditions and pressures accompanied by urbanization via individual-level adaptation.

Over the past 30 yr, multiple species of predatory Coccinellidae, prominently Coccinella septempunctata L. and Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) have spread to new continents, influencing biodiversity and biological control. Here we review the mechanisms underlying these ecological interactions, focusing on multi-year field studies of native and non-native coccinellids and those using molecular and quantitative ecological methods. Field data from Asia show that H. axyridis, C. septempunctata, and Propylea japonica (Thunberg) (Coleoptera: Coccinellidae) are regularly among the most abundant predatory species but their rank varies by habitat. Studies of these species in their native Asian range, primarily related to their range in mainland China, document different patterns of seasonal abundance, species specific associations with prey, and habitat separation. Intraguild predation is well documented both in Asia and in newly invaded areas, and H. axyridis benefits most from this interaction. Harmonia axyridis also seems to rely more on cannibalism in times of prey scarcity than other species, and relatively sparse data indicate a lower predation pressure on it from natural enemies of coccinellids. Declines in the abundance of native coccinellids following the spread and increase of non-native species, documented in several multi-year studies on several continents, is a major concern for native biodiversity and the persistence of native coccinellid species. We suggest that future studies focus more attention on the community ecology of these invasive species in their native habitats. China Scholarship CouncilChina Scholarship Council; National Key R&D Program of China [2017YFE0104900]; National Institute of Food and Agriculture, United States Department of Agriculture, Hatch Program [1008480] Published version We thank the China Scholarship Council for a scholarship supporting H. Li's research in the Department of Entomology at the University of Kentucky. This work was supported by the National Key R&D Program of China (2017YFE0104900, to B. Li). J.J.O. was supported by the National Institute of Food and Agriculture, United States Department of Agriculture, Hatch Program under accession number 1008480.

Monitoring ecosystem processes resulting in ecosystem services (ESs) and disservices (EDs) is crucial in agricultural ecosystems. Traditionally, ESs/EDs provided by arthropods have been estimated indirectly by measuring arthropod abundance and diversity, overlooking the recognised limitations of such approach. Using a consistent methodology based on the sentinel approach, we quantified the intensity of five ecological processes leading to four ESs and two EDs in vineyards and citrus orchards on Terceira Island, Azores. We assessed herbivory rates on lettuce plants (ED), predation rates on green plasticine caterpillars by vertebrates and invertebrates (ES), the intensity of insect pollination on strawberry plants (ES), the rates of predation on wheat and dandelion seeds (ED and ES, respectively) by rodents and invertebrates, and decomposition rates using tea and rooibos leaves (ES). Herbivory rates after 2 weeks were significantly lower in vineyards (mean ± SD; 0.5 ± 0.6%) than in citrus orchards (3.6 ± 2.9%). Vertebrate predation rates in vineyards (4.0 ± 13.6% d⁻¹) were significantly higher than in citrus orchards (2.4 ± 10.7% d⁻¹), while no differences were observed for overall and invertebrate predation rates. Pollination efficiency in vineyards (214.5 ± 23.9 seeds/fruit) was significantly higher than in citrus orchards (162.0 ± 14.7 seeds/fruit). Seed predation rates were higher, although not significantly so, in citrus orchards (2.0 ± 5.8% d⁻¹) than in vineyards (0.3 ± 0.8% d⁻¹). Decomposition was significantly higher on tea than on rooibos leaves, both in vineyards (1.15 ± 0.11 g vs. 0.72 ± 0.16 g) and citrus orchards (1.34 ± 0.06 g vs. 0.78 ± 0.13 g); no differences between mass loss in the two habitats were observed. Our results demonstrated the suitability of simple, direct monitoring tools for a quantitative comparison of agricultural habitats, confirm that landscape complexity does not always support ESs, and that the same agro-ecosystem characteristics that support ESs could occasionally also favour EDs. This work was financed by FEDER (European Regional Development Fund) in 85% and by Azorean Public Funds by 15% through Operational Program Azores 2020, under the project AGRO-ECOSERVICES (ACORES-01-0145-FEDER-000073). info:eu-repo/semantics/publishedVersion

Worldwide human-induced habitat fragmentation intensifies the emergence of forest edges. In addition to these edges, there are edges evolved by natural processes. Edge-maintaining processes (natural vs. anthropogenic) fundamentally determine edge responses, and thus edge functions. Species with various traits show fundamentally different edge response, therefore the trait-based approach is essential in edge studies. We evaluated the edge effect on the body size of ground beetles in forest edges with various maintaining processes. Our results, based on 30 published papers and 221 species, showed that natural forest edges were impenetrable for small species, preventing their dispersal into the forest interiors, while both the medium and the large species penetrated across these edges and dispersed into the forest interiors. Anthropogenic edges maintained by continued human disturbance (agriculture, forestry, urbanisation) were permeable for ground beetles of all size, allowing them to invade the forest interiors. Overwintering type (overwintering as adults or as larvae) was associated with body size, since almost two-thirds of the small species, while slightly more than a third of both the medium and the large species were adult overwintering. Based on this, size-dependent permeability of natural edges may be related to overwintering type, which basically determines species tolerance to human disturbance.

14 páginas, 3 figuras, Urbanization is an important driver of the diversity and abundance of tree-associated insect herbivores, but its consequences for insect herbivory are poorly understood. A likely source of variability among studies is the insufficient consideration of intra-urban variability in forest cover. With the help of citizen scientists, we investigated the independent and interactive effects of local canopy cover and percentage of impervious surface on insect herbivory in the pedunculate oak (Quercus robur L.) throughout most of its geographic range in Europe. We found that the damage caused by chewing insect herbivores as well as the incidence of leaf-mining and gall-inducing herbivores consistently decreased with increasing impervious surface around focal oaks. Herbivory by chewing herbivores increased with increasing forest cover, regardless of impervious surface. In contrast, an increase in local canopy cover buffered the negative effect of impervious surface on leaf miners and strengthened its effect on gall inducers. These results show that-just like in non-urban areas-plant-herbivore interactions in cities are structured by a complex set of interacting factors. This highlights that local habitat characteristics within cities have the potential to attenuate or modify the effect of impervious surfaces on biotic interactions., This study was carried out with financial support from the French National Research Agency (ANR) in the frame of the Investments for the Future Programme, within the Cluster of Excellence COTE (Continental To coastal Ecosystems: evolution, adaptability, and governance) (ANR-10-LABX-45) and was further funded by the BNP Paribas Foundation as part of its Climate & Biodiversity Initiative the citizen science project Tree Bodyguards. The authors warmly thank all the young European citizens and their teachers who made this study possible. They also thank the professional scientists who kindly agreed to participate in this study: Alexander Kozel (Belarusian State Technological University and American Psychological Association), Andreas Schuldt (Forest Nature Conservation, Georg-August-University Göttingen, Göttingen, German), Aurélien Sallé (Laboratoire de Biologie des Ligneux et des Grandes Cultures, INRAE, Université d'Orléans), Chloe Mendiondo and Claire Colliaux (Department of Agroecology, Aarhus University, Flakkebjerg Research Centre, DK-4200 Slagelse, Denmark), György Csóka (Department of Forest Protection, NARIC Forest Research Institute, Mátrafüred, Hungary), Lars Opgennoorth (Biodiversity and Conservation Biology, Ecological Genetics, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland), Laurent Augusto (INRAE, Bordeaux Sciences Agro), Marija Popović (Faculty of Forestry, University of Belgrade, Belgrade, Serbia), Mickael Pihain (Research Unit “Ecosystèmes, Biodiversité, Evolution”, University of Rennes 1/CNRS, 35042 Rennes, France), Olivier Bouriaud (Applied Ecology Laboratory, Forestry Faculty, “Ștefan cel Mare, University of Suceava, Suceava, Romania), Stefan K. Müller (Freie evangelische Schule Lörrach), Tomas Roslin (Department of Ecology; Swedish University of Agricultural Sciences), Valentin Queloz (Forest Entomology, Swiss Federal Research Institute WSL), and Vojtech Lanta (Institute of Botany CAS, Dukelská 135, 37901 Třeboň, Czech Republic). They also thank Michael Scherer-Lorenzen (Geobotany, Faculty of Biology, University of Freiburg) for the help during the coordination of the research.

Describing and conserving ecological interactions woven into ecosystems is one of the great challenges of the 21st century. Here, we present a unique dataset compiling the biotic interactions between two ecologically and economically important taxa: ground beetles (Coleoptera: Carabidae) and fungi. The resulting dataset contains the carabid-fungus associations collected from 392 scientific publications, 129 countries, mostly from the Palearctic region, published over a period of 200 years. With an updated taxonomy to match the currently accepted nomenclature, 3,378 unique associations among 5,564 records were identified between 1,776 carabid and 676 fungal taxa. Ectoparasitic Laboulbeniales were the most frequent fungal group associated with carabids, especially with Trechinae. The proportion of entomopathogens was low. Three different formats of the data have been provided along with an interactive data digest platform for analytical purposes. Our database summarizes the current knowledge on biotic interactions between insects and fungi, while offering a valuable resource to test large-scale hypotheses on those interactions., Measurement(s)species associationsTechnology Type(s)digital curationFactor Type(s)associations between Carabidae and FungiSample Characteristic - OrganismCarabidae • Fungi • LaboulbenialesSample Characteristic - Locationglobal Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14602770

Repeatability is the cornerstone of science, and it is particularly important for systematic reviews. However, little is known on how researchers’ choice of database, and search platform influence the repeatability of systematic reviews. Here, we aim to unveil how the computer environment and the location where the search was initiated from influence hit results.We present a comparative analysis of time‐synchronized searches at different institutional locations in the world and evaluate the consistency of hits obtained within each of the search terms using different search platforms.We revealed a large variation among search platforms and showed that PubMed and Scopus returned consistent results to identical search strings from different locations. Google Scholar and Web of Science's Core Collection varied substantially both in the number of returned hits and in the list of individual articles depending on the search location and computing environment. Inconsistency in Web of Science results has most likely emerged from the different licensing packages at different institutions.To maintain scientific integrity and consistency, especially in systematic reviews, action is needed from both the scientific community and scientific search platforms to increase search consistency. Researchers are encouraged to report the search location and the databases used for systematic reviews, and database providers should make search algorithms transparent and revise access rules to titles behind paywalls. Additional options for increasing the repeatability and transparency of systematic reviews are storing both search metadata and hit results in open repositories and using Application Programming Interfaces (APIs) to retrieve standardized, machine‐readable search metadata., The consistency level with which scientific search platforms return hits for the same search initiated at different locations and from different computing environments was investigated. Scopus and PubMed returned the same results regardless of the location or computing environment but Web of Science and Google Scholar varied substantially. Since this is a crucial issue for the repeatability of systematic reviews, action should be taken to improve the within‐database consistency in the returned search hits.

The seasonal activity of six carabid species (Nebria brevicollis, Carabus nemoralis, C. hortensis, C. coriaceus, Pterostichus melanarius and Abax parallelepipedus) was studied along an urbanisation gradient (rural forest – suburban forest – forest fragments in urban park) in Sorø, Denmark, during April–October 2004 and 2005.Two groups were identified: 1) Species with constant seasonality, in which seasonal activity profiles did not differ along the gradient (C. hortensis, C. coriaceus, and A. parallelepipedus); 2) Species with flexible seasonality,with remarkable differences along the gradient and between the years (C. nemoralis, N. brevicollis and P. melanarius). In four out of six studied species, 2005 was less favourable than 2004. Spring activity in the urban habitat started earlier than in the suburban or forested ones. A better understanding of urban green infrastructures in biodiversity assessments may need the study of seasonality in order to distinguish whether the bioindicator’s responses are to habitat quality or stochastic seasonal events.

Edges are on the increase world-wide due to increasing fragmentation and loss of natural habitats. After formation, edges are maintained by various processes (natural vs. continued anthropogenic interventions: forestry, agriculture, urbanization) which influence the reaction of individual species to edge effects (history-based edge effect hypothesis), and this will be reflected in the diversity of assemblages. Diversity, however, is not the most appropriate indicator of the edge effect because species with different traits may respond differently to the edges. To further articulate the history-based edge effect hypothesis, we evaluated the edge effect on one of the most commonly used life-history traits, the feeding habit of ground beetles in forest edges. A meta-analysis based on 28 publications and 422 comparisons showed that natural vs. continued anthropogenic interventions as edge-maintaining processes reflected at the trait level. Abundance of herbivorous, omnivorous, and predatory ground beetle species were all higher in the natural edges than in the forest interiors, while no similar pattern occurred in edges with continued anthropogenic influence. These results suggest that structural and environmental changes at edges sustained by repeated anthropogenic influence adversely influencing ecosystem functions, with negative effects on ecosystem services like pest or weed control.

AIM: The strength of species interactions is traditionally expected to increase toward the Equator. However, recent studies have reported opposite or inconsistent latitudinal trends in the bottom-up (plant quality) and top-down (natural enemies) forces driving herbivory. In addition, these forces have rarely been studied together thus limiting previous attempts to understand the effect of large-scale climatic gradients on herbivory. LOCATION: Europe. TIME PERIOD: 2018–2019. MAJOR TAXA STUDIED: Quercus robur. METHODS: We simultaneously tested for latitudinal variation in plant–herbivore–natural enemy interactions. We further investigated the underlying climatic factors associated with variation in herbivory, leaf chemistry and attack rates in Quercus robur across its complete latitudinal range in Europe. We quantified insect leaf damage and the incidence of specialist herbivores as well as leaf chemistry and bird attack rates on dummy caterpillars on 261 oak trees. RESULTS: Climatic factors rather than latitude per se were the best predictors of the large-scale (geographical) variation in the incidence of gall-inducers and leaf-miners as well as in leaf nutritional content. However, leaf damage, plant chemical defences (leaf phenolics) and bird attack rates were not influenced by climatic factors or latitude. The incidence of leaf-miners increased with increasing concentrations of hydrolysable tannins, whereas the incidence of gall-inducers increased with increasing leaf soluble sugar concentration and decreased with increasing leaf C : N ratios and lignins. However, leaf traits and bird attack rates did not vary with leaf damage. MAIN CONCLUSIONS: These findings help to refine our understanding of the bottom-up and top-down mechanisms driving geographical variation in plant–herbivore interactions, and indicate the need for further examination of the drivers of herbivory on trees. This study was carried out with financial support from the French National Research Agency (ANR) in the frame of the Investments for the Future Programme, within the Cluster of Excellence COTE (Continental To coastal Ecosystems: evolution, adaptability and governance) (ANR-10-LABX-45). E.V.C. was funded by the BiodivERsA (BiodivERsA is a network of national and regional funding organisations promoting pan-European research on biodiversity and ecosystem services, and offering innovative opportunities for the conservation and sustainable management of biodiversity) project SPONFOREST (Unraveling the potential of spontaneous forest establishment for improving ecosystem functions and services in dynamic landscapes) (BiodivERsA3-2015-58). info:eu-repo/semantics/publishedVersion

Deserts, despite being extreme environments, contain multiple habitats of different productivity and vegetation structure, affecting the abundance and diversity of desert arthropods. Predatory arthropods may be exceptionally diverse where scattered vegetation provides micro-habitats, concentrations of prey, and protection from predation risk. We examined the effect of habitat differences and local vegetation structure on abundance, diversity and assemblage composition of ground-active spiders in the Negev desert, Israel. Our monthly pitfall trapping in four main habitat types – dunes, loess plain, rocky slopes and wadis (dry watercourses), collected 5937 adults of 136 species. The abundance of ground-active spiders was highest in the dunes due to two dominant species, Haplodrassus pugnans and Zodarion nitidum. Both habitat and season significantly affected species richness, which peaked in the warm season; wadis had consistently higher species richness (63–74 spp.) than other habitats (48–61 spp.). Vegetation height positively correlated with both species richness and abundance in all habitats. Spider assemblages in the same, but geographically distant, habitats were more similar than those in adjacent but different habitats. Several numerically dominant species were habitat specialists. Our results confirm the need for large- and local-scale habitat management to maintain spider diversity in the face of increasing anthropogenic threats. US-Israel Binational Science Foundation (1989/060); Jacob Blaustein Center for Scientific Cooperation; Jacob Blaustein Center for Scientific Co-operation. info:eu-repo/semantics/publishedVersion

AIM: Urbanization profoundly changes environments, ecosystems and biodiversity. The urban heat island (UHI) effect represents one of the most consistent human-induced environmental change in urbanized areas. Recently, it was observed that the UHI causes community-wide shifts towards species with smaller body sizes in urban communities of ectotherms due to increased metabolic costs. We here assembled a large dataset of published data of geographically distant carabid communities collected along urbanization gradients to examine whether we could confirm this consistent change in body size distribution. LOCATION: Rural and urban forests at 11 northern temperate locations, spanning 25 latitudinal degrees. TIME PERIOD: 2002-2018. MAJOR TAXA STUDIED: Species of ground beetles (Coleoptera: Carabidae). METHODS: We evaluated size distribution changes using community-weighted mean body sizes of ground beetles collected from similarly vegetated rural and urban habitats between 2002 and 2018. We separately examined the UHI effect on the various sub-assemblages of the carabid community. RESULTS: When analysing the entire dataset, we could not detect any clear trend in the community body size mean, with urban communities showing similar values to those sampled in rural areas. However, the sub-assemblage of forest habitat specialists consistently displayed a significant shift towards smaller species from rural to urban habitats. The inconsistent trend at the community level was likely due to the influx into urban habitat fragments of non-specialist species. The UHI effect also had a significant influence but only on the forest specialist sub-assemblage. MAIN CONCLUSIONS: Our results indicated that forest-specialist species were most affected by the UHI as a powerful urbanization-related environmental filter, whereas this effect was not evident for the overall community. Urban management practices should aim to minimize the intensity of urbanization-related environmental filters such as the UHI, to enable habitat specialists to survive in habitat fragments under urbanized conditions. Aarhus University Forskningsfond; Hungarian National Research, Development and Innovation Fund (OTKA K-131459) info:eu-repo/semantics/publishedVersion

Habitat conversion in mountain areas threatens their biodiversity. The effect on biodiversity of creating a mountain landscape with a network of forest fragments and a cultivated habitat matrix is poorly documented in China. Bird communities in forest fragments and tea plantations were censused by field observations in two years (2018&ndash, 2019) in three tea-growing locations, Anxi, Beifeng, and Wuyishan in Fujian Province, south-eastern China. Out of a potential pool of 247 forest-associated bird species, we detected the presence of 82, mostly resident species, 32&ndash, 47 of those regularly visiting tea plantations. Species-accumulation curves indicated the near-completeness of the census. The R&eacute, nyi diversity profiles indicated a more diverse community in forest fragments than nearby tea plantations at Anxi and Beifeng, but the tea plantations at Wuyishan supported a more diverse bird community than the forest. Avian communities in tea plantations were a significantly nested subset of the forest communities. Tea plantations can provide resources for forest-associated birds, but the effectiveness of preserving avian diversity depends on natural forest fragments and can be enhanced by landscape-scale management, when the biocontrol potential of birds can also be enhanced.

Scientific knowledge in the field of ecology is increasingly enriched by data acquired by the general public participating in citizen science (CS) programs. Yet, doubts remain about the reliability of such data, in particular when acquired by school children. We built upon an ongoing CS program - Oak bodyguards - to assess the ability of European schoolchildren to accurately estimate the strength of biotic interactions in terrestrial ecosystems. We used standardized protocols to estimate predation rates on artificial caterpillars and insect herbivory on oak leaves and compared estimates made by school children, trained and untrained professional scientists (with no or limited expertise in predation or herbivory assessment). Compared to trained scientists, both schoolchildren and untrained professional scientists overestimated predation rates, but assessments made by the latter were more consistent. School children overestimated insect herbivory, as did untrained professional scientists. Thus, raw data acquired by school children participating in CS programs cannot be used and require several quality checks. However, such data are of no less value than data collected by untrained professional scientists and can be calibrated for bias.

Forest edges are formed by natural or anthropogenic processes and their maintaining processes cause fundamentally different edge responses. We evaluated the published evidence on the effect of various edges on the abundance of ground beetles of different habitat affinity and dispersal power. Our results, based on 23 publications and 86 species, showed that natural forest edges were impenetrable for open-habitat species with high dispersal power, preventing their influx into the forest interiors, while forest specialist species of limited dispersal power penetrated and reached abundances comparable to those in forest interiors. Anthropogenic edges, maintained by continued disturbance were permeable by macropterous open-habitat species, allowing them to invade the forest interiors, while such edges (except the forestry-induced ones) deterred brachypterous forest specialists. Different permeability of forest edges with various maintaining processes can affect ecosystem functions and services, therefore the preservation and restoration of natural forest edges are key issues in both forest ecology and nature conservation.

Tea (Camellia sinensis) is an important food product with thousands of years of human use. Being a non-washable food, no pesticide residues are allowed, which increases the importance of natural means of plant protection. Predation, a component of natural pest control, is an important contributor to this, but its level and sustainability are not known in most of the areas of tea production. We quantified predation intensity using the artificial sentinel prey method in a tea-growing landscape containing remnants of the original forest vegetation in Fujian Province, China. The most common predators were chewing arthropods (49.8% of predation events) and birds (48.1%). Overall, predation rates at the edges of forest fragments (18.9% d-1) were lower than either in fragment interiors (25.4%d&minus, 1) or in the surrounding tea plantations (19.2&ndash, 24.1%d-1). Arthropod predation was higher inside, and at the edge of, forest fragments than within plantations, and generally decreased with increasing distance from a fragment edge, indicating limited spillover of arthropod predators from the native habitat remnants to the cultivated matrix at the local scale. Bird predation, though, showed a different trend: it was lower on the inside of forest fragments than in the tea planation, and bird attack rates increased at increasing distances (up to 40 m) from the forest fragment edge. We also found a reciprocal relationship between attack rates by birds and arthropods, suggesting intra-guild predation. Measures protecting arthropod natural enemies could increase the combined pest suppression effect, contributing to pesticide-free tea production in China.

Urbanization is one of the most important global trends which causes habitat reduction and alteration which are, in turn, the main reasons for the well-documented reduction in structural and functional diversity in urbanized environments. In contrast, effects on ecological mechanisms are less known. Predation is one of the most important ecological functions because of its community-structuring effects. We studied six forest habitats along a riverside urbanization gradient in Szeged, a major city in southern Hungary, crossed by the river Tisza, to describe how extreme events (e.g., floods) as primary selective pressure act on adaptation in riparian habitats. We found a generally decreasing predation pressure from rural to urban habitats as predicted by the increasing disturbance hypothesis (higher predator abundances in rural than in urban habitats). The only predators that reacted differently to urbanization were ground active arthropods, where results conformed to the prediction of the intermediate disturbance hypothesis (higher abundance in moderately disturbed suburban habitats). We did not find any evidence that communities exposed to extreme flood events were preadapted to the effects of urbanization. The probable reason is that changes accompanied by urbanization are much faster than natural landscape change, so the communities cannot adapt to them.

Urbanization effects on terrestrial isopod (Isopoda, Oniscidea) populations were studied in forested areas along a rural-to-urban gradient including a native beech forest, suburban and urban forest fragments in Soro, Denmark. The seasonal activity patterns of the dominating species (Oniscus asellus, Philoscia muscorum and Porcellio scaber) indicated differences among the areas, but these patterns were idiosyncratic. There were more females than males in most areas. The seasonal patterns of males and non-gravid females were similar and often bimodal; gravid females showed markedly different, usually unimodal activity patterns. Temporal changes of sex ratios were — in each species — characterized by an early summer activity peak of males, followed by the activity peak of gravid females. We suggest that these trends might indicate a reproduction-driven surface activity of males. The small response of the three isopod species to urbanization may reflect their wide ecological tolerance as well as the “soft management” of the urban park.

We suggest the use of a graphical method, involving a standardisation of the seasonal activity curves and their subsequent comparison by a percentile-percentile graph as an easy way to compare seasonal activities in arthropods. To test the suitability of the suggested method, the seasonal dynamics of three common carabid beetles, Pterostichus melanarius, Nebria brevicollis and Carabus nemoralis were compared in three habitats (rural forest, suburban and urban forest fragments) along an urbanisation gradient near Soro, Denmark, in 2004 and 2005. Activity in urban habitats often started earlier, possibly caused by the warmer microclimate in the city centre. The comparative graphs indicated the unsuitability of the suburban habitat for N. brevicollis, and the differential suitability as overwintering habitat of the three urbanisation stages for C. nemoralis. The method seems suitable to analyse differences in seasonal activity while being more sensitive than traditional seasonal-activity graphs.

The establishment of a sustainable land use system is crucial in Hungary (SE Europe) where 30% of croplands lie on former floodplains, and 40–45% of arable lands are drought-prone. We calculated and compared the monetary value of the main wetland ecosystem services, the profitability of land use and the additional costs of grain producer system on land at risk from groundwater inundation on the Hungarian Plain. We show that orchards and forestry generate a much higher profitability in former wetlands than cropland farming. Using the replacement cost method, we prove that the reservoir capacity of restored wetlands with an ecologically optimal 0.5 m water depth could replace 2150 €ha−1 flood protection investment cost. The calculated costs of protecting land under the two highest groundwater risk categories between 1999–2005 was 37.2 €ha−1 y−1 and 14.9 €ha−1 y−1, respectively. Although the flood protection benefits of former wetlands may provide an appropriate value base for restoration per se, combined with the potential advantages of land use change from cropland to forest in former wetlands and the carbon sequestration benefit provide ‘win-win’ solutions for land users and institutional actors interested in flood prevention, environmental protection and climate mitigation.

Numerous recent studies report an alarming decrease in diversity, biomass, or abundance of arthropods in various habitats. Given that they are important food for other organisms, the ecological consequences of such a decline could be severe. We used data from the Hungarian Forestry Light Trap Network to examine whether the spring caterpillar biomass showed any long term (23–58 years) declining trend in oak-dominated forests. Light trap data for 43 selected macrolepidopteran species (suitable bird food in the larval stage) from six different locations were used for the estimation of the total available caterpillar biomass. Time series analyses showed strong year-to-year fluctuations, and over all locations and time windows there was an increasing rather than decreasing trend. The increase found at some locations may suggest increasing herbivore pressure and negative impacts on forest health. We conclude that foliage-feeding macrolepidopteran species with spring-developing larvae did not show a drastic decrease in recent decades, and food availability in the long term will not negatively influence the breeding success of birds in such forests.

Humankind draws important benefits from large-scale ecological processes termed ecosystem services, yet the status of several of them is declining. Reliable monitoring methods are essential for tracking the status of ecosystem services. Predation is the mainstay of natural pest control, a key ecosystem service. We used green plasticine caterpillars to monitor predation pressure, and to obtain baseline data on predator activity in transgenic Bt versus non-Bt maize fields in Old and New World countries. Predation pressure was measured at ground and canopy levels using an identical, small-plot experimental design in four European countries (Denmark, Slovakia, Romania and Italy) and Argentina. Total predation rate in maize was 11.7%d −1 (min. 7.2%d −1 in Argentina, max. 29.0%d −1 in Romania). Artificial caterpillars were attacked both by invertebrates (mostly chewing insects with 42.0% of the attack marks, and ants with 7.1%, but also predatory and parasitoid wasps, spiders and slugs), and vertebrates (small mammals 25.5%, and birds 20.2%). Total predation at ground level (15.7%d −1 ) was significantly higher than in maize canopies (6.0%d −1 ) in all countries, except Argentina. We found no significant differences between predator pressure in Bt versus non-Bt maize plots. The artificial caterpillar method provided comparable, quantitative data on predation intensity, and proved to be suitable for monitoring natural pest control. This method usefully expands the existing toolkit by directly measuring ecological function rather than structure.

Physiological condition of an animal is flexible and can quickly change in relation to the quality of its environment. This makes it potentially suitable as an estimator of environmental stress. We studied the condition in three predatory ground beetles, Carabus nemoralis, Nebria brevicollis and Pterostichus melanarius along an urbanisation gradient (forest-suburban area - forest fragments in urban park) in Soro, Denmark to test whether urbanisation-related stress is reflected in body condition. We also considered the interaction between condition and the true asymmetry using a local polynomial regression model. Females showed consistently better condition than males in all studied species. The condition indices in C. nemoralis and N. brevicollis were higher in the urban habitats than the other sites, while P. melanarius showed better condition in the suburban forest fragments than the forest or urban habitats. A significant negative correlation was found between condition and asymmetry for C. nemoralis and N. brevicollis in the suburban as well as urban forest fragments. This indicates a complex interaction between tolerance limits, feeding conditions and stress levels during advancing urbanisation, emphasising the importance of using multiple criteria for assessing its impact on biodiversity.

In a fragmented landscape, transitional zones between neighbouring habitats are common, and our understanding of community organisational forces across such habitats is important. Edge studies are numerous, but the majority of them utilise information on species richness and abundance. Abundance and taxonomic diversity, however, provide little information on the functioning and phylogeny of the co-existing species. Combining the evaluation of their functional and phylogenetic relationships, we aimed to assess whether ground beetle assemblages are deterministically or stochastically structured along grassland-forest gradients. Our results showed different community assembly rules on opposite sides of the forest edge. In the grassland, co-occurring species were functionally and phylogenetically not different from the random null model, indicating a random assembly process. Contrary to this, at the forest edge and the interior, co-occurring species showed functional and phylogenetic clustering, thus environmental filtering was the likely process structuring carabid assemblages. Community assembly in the grassland was considerably affected by asymmetrical species flows (spillover) across the forest edge: more forest species penetrated into the grassland than open-habitat and generalist species entered into the forest. This asymmetrical species flow underlines the importance of the filter function of forest edges. As unfavourable, human-induced changes to the structure, composition and characteristics of forest edges may alter their filter function, edges have to be specifically considered during conservation management. This article is protected by copyright. All rights reserved

South America is undergoing a rapid and large scale conversion of natural habitats to cultivated land. Ecosystem services (ESs) still remain important but their level and sustainability are not known. We quantified predation intensity in an Argentinian agricultural landscape containing remnants of the original chaco serrano forest by using artificial sentinel prey. We sought to identify the main predators, and the effect of landscape configuration and maize phenology on predation pressure by invertebrate and vertebrate predators in this landscape. The most common predators were chewing insects (50.4% predation events), birds (22.7%), and ants (17.5%). Overall predation rates in forest fragments (41.6% d-1) were significantly higher than in the surrounding maize fields (21.5% d-1). Invertebrate predation was higher inside and at the edge of forest fragments than within fields, and did not change with increasing distance from a fragment edge, indicating a lack of spillover from the native habitat remnants to the cultivated matrix at the local scale. Distance from a continuous forest had a positive impact on predation by invertebrates and a negative impact on vertebrate predation. Fil: Ferrante, Marco. Aarhus University. Flakkebjerg Research Centre. Department of Agroecology; Dinamarca Fil: González, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Gabor L., Lovei. Aarhus University. Flakkebjerg Research Centre. Department of Agroecology; Dinamarca

Sentinel prey can provide a direct, quantitative measure of predation under field conditions. Live sentinel prey provides more realistic data but rarely allows the partitioning of the total predation pressure; artificial prey is less natural but traces left by different predators are identifiable, making it suitable for comparative studies. We reviewed the available evidence of the use of both types of invertebrate sentinel prey. Fifty-seven papers used real prey, usually measuring predation on a focal (often pest) species, with studies overwhelmingly from North America. The median predation was 25.8% d-1 . Artificial sentinel prey (45 papers) were used in both temperate and tropical areas, placed more above ground than at ground level. The most commonly used artificial prey imitated a caterpillar. Up to 14 predator groups were identified, registering a median of 8.8% d-1 predation; half the studies reported only bird predation. Predation on real prey was higher than on artificial ones, but invertebrate predation was not higher than vertebrate predation. Invertertebrate but not vertebrate predation was negatively related to prey size. Predation near the Equator was not higher than at higher latitudes, nor in cultivated than noncultivated habitats. The use of sentinel prey is not yet standardised in terms of prey size, arrangement, exposure period or data reporting. Due to the simplicity and ease of use of the method, such standardisation may increase the usefulness of comparative studies, contributing to the understanding of the importance and level of predation in various habitats worldwide.

Urbanization is one of the most important processes shaping our environment, which causes habitat reduction and alteration which are, in turn, the main reasons for the reduced structural and functional diversity in urbanized environments. Predation is one of the most important ecological functions because of its community-structuring effects. Quantification of predation on invertebrate prey is difficult, because the attacks are mostly cryptic and it is rare when evidence is present. Using dummy prey, which is fixed to a surface, the marks left by predators allows us to identify them. Current evidence indicates that predation pressure is lower in urban than rural areas. According to the natural flow-regime paradigm, extreme events (e.g. floods) constitute a primary adaptive pressure in riparian habitats. We tested the validity of the paradigm in urbanized habitats. Our study site was in and around the city of Szeged (Hungary), along two urbanization gradients selected according to the Globenet protocol along the banks of the river Tisza and Maros. Data collection was conducted from April to October, 2014-2016. Both urbanization gradients included rural, suburban and urban areas, each characterised by an increase in the built up area (0%-25%-50%), intensity of forest management, and visitation rates by city residents. Overall 12672 dummy caterpillars ware placed, 6336 were on the ground level and 6336 on tree trunks. The dummy caterpillars (20 mm long, 3 mm thick) were made of light green plasticine, using a modified garlic press, fixed to the bark of trees or on a suitable surface on the ground with superglue, exposed for 24 h. The marks were identified using a hand-held magnifying glass (10 x). Overall the most active predator group was small mammals, followed by insects and birds. Urban predation activity on ground level, caused mainly by carabid beetles was significantly lower than the suburban or rural ones. Carabid predation pressure was higher in suburban than in rural habitats, while all other predator groups (other insects, birds and small mammals) had a decreasing trend towards urban habitats. This means, that all studied predator groups act according to the Gray’s increasing disturbance hypothesis, while carabid beetles react to urbanization according to Connell’s intermediate disturbance hypothesis. We found no evidence for the natural flow-regime paradigm along the examined urbanization gradients.

We studied the effects on spiders of a three-step rural-urban urbanisation gradient near a Danish town embedded in a historically forested landscape. Using pitfall traps set in forested habitat patches, we collected a total of 3075 adult spiders of 80 species; the habitats under different degrees of urbanisation had 45–47 species. We found support for Gray’s Increasing Disturbance Hypothesis: the species richness trap −1 was significantly higher in the rural habitat than in any other one, and decreased from the rural forest to forest fragments dominated by non-native trees in the urban park. The number of forest specialist species also decreased along the urbanisation gradient. Neither the presence of generalists nor light-preferring species increased under more urbanised conditions, but web builders and hygrophilous species were more species-rich in the rural habitat than elsewhere. Using indicator values, we identified Coelotes atropos, Walckenaeria corniculans, Walckenaeria cucullata, and Pachygnatha listeri as species linked to the rural and suburban habitats; Trochosa terricola, Saaristoa abnormis, Robertus lividus as characteristic of the rural habitat; and Gongylidium rufipes and Diplocephalus latifrons as urban habitat specialists.

Scientific knowledge in the field of ecology is increasingly enriched by data acquired by the general public participating in citizen science (CS) programs. Yet, doubts remain about the reliability of such data, in particular when acquired by schoolchildren. We built upon an ongoing CS program, Oak Bodyguards, to assess the ability of schoolchildren to accurately estimate the strength of biotic interactions in terrestrial ecosystems. We used standardized protocols to estimate attack rates on artificial caterpillars and insect herbivory on oak leaves. We compared estimates made by schoolchildren with estimates made by professional scientists who had been trained in predation and herbivory assessments (henceforth, trained scientists), and trained scientists’ estimates with those made by professional scientists with or without expertise (untrained) in predation or herbivory assessment. Compared with trained scientists, both schoolchildren and untrained professional scientists overestimated attack rates, but assessments made by the latter were more consistent. Schoolchildren tended to overestimate insect herbivory, as did untrained professional scientists. Raw data acquired by schoolchildren participating in CS programs therefore require several quality checks by trained professional scientists before being used. However, such data are of no less value than data collected by untrained professional scientists. CS with schoolchildren can be a valuable tool for carrying out ecological research, provided that the data itself is acquired by professional scientists from material collected by citizens.

Urbanization is one of the most important global trends which causes habitat reduction and alteration which are, in turn, the main reasons for the reduced structural and functional diversity in urbanized environments. Predation is one of the most important ecological functions because of its community-structuring effects. According to previous studies effects of urbanization on predation rates appear inconsistent. Predator species are vulnerable to habitat alteration and loss caused by urbanization, therefore, we hypothesised that predation rate would decrease along the rural-urban gradient. To clarify the impact of urbanization on predation, we performed a meta-analysis on predation rates in rural vs. urban areas using published data of 25 studies. Predation rates on taxa other than birds were underrepresented, preventing an overall evaluation. Reported predation rates on birds were significantly higher in rural than in urban habitats.

Diversity changes can be evaluated at various spatial scales, and the relationship between changes in diversity at the local, landscape and regional scales is not evident. The overall patterns of functional and beta diversity of bird assemblages were evaluated along a five-stage urbanization gradient, censused over the months of January to April in the years 2010–2013, in and around Amravati city, Deccan Plateau, Central India. We expected the abundance of large and predatory species to decline along the gradient, and urbanization to homogenize species richness at the landscape level. Overall, 112,829 birds belonging to 89 species were identified in the region, and species richness decreased from the rural forest (73 species) to more urbanized areas (lowest at the centre of Amravaty city with 29 species). Along the urbanization gradient, bird assemblages contained more small species, and the share of frugivorous and omnivorous species also increased, while that of insectivorous species decreased. Diversity partitioning indicated that of the overall pattern, local (alpha) diversity accounted for 50.1% of the total (gamma) diversity, and urbanization stages another 36.2%; the contribution of within-stage, local diversity was rather small (2.7%), indicating fairly homogeneous assemblages.

We censused terrestrial bird assemblages along a five-stage urbanisation gradient (rural forest, industrial zone, peri-urban, suburban and urban habitats) in and around Amravati City, Central India ...

Lepidoptera is one of the most diverse orders of insects, their larvae are very abundant in many habitats, and frequent prey of various predators. To decrease predation risk, caterpillars developed several means of defence, among them timing their activity to avoid predators (seeking enemy-free time). Although the enemy-free time hypothesis is often invoked to explain caterpillar behaviour, empirical evidence for it is scarce. We tested whether such enemy-free time exists in a temperate forest by comparing predation pressure on artificial caterpillars during day and night on the ground in forest fragments in Denmark. We found a high predation rate, 23.9% d(-1), and higher predation rate at night (30.9% d(-0.5)) than during the day (17.0% d(-0.5)), both by invertebrate (23.3% d(-0.5) vs. 12.4% d(-0.5)) and vertebrate (8.5% d(-0.5) vs. 3.3% d(-0.5)) predators. The most important predators were chewing insects (73.4% of all attacks) and small mammals (19.0%). Attack rates on red caterpillars were higher (30.0% d(-1)) than on green ones (19.5% d(-1)). Overall, these data do not support the idea that night activity can provide enemy-free time for solitary caterpillars on the temperate forest floor.

The sentinel prey method can quantify predation pressure in various habitats. Real prey is assumed to more realistically mimic the predator experience but the predator can rarely be identified. Artificial prey made of plasticine may lack real chemical cues, but provides information about predator identity. However, the relationship between predation pressure registered by artificial versus real prey is not clear. We tested the relative attractiveness of artificial caterpillars, and intact, wounded, or dead larvae of the cabbage moth (Mamestra brassicae) for the carabid predator Pterostichus melanarius Illiger (Coleoptera: Carabidae). P. melanarius adults were attracted to dead caterpillars more than to live or wounded ones. Coating artificial caterpillars with caterpillar haemolymph increased their attractiveness. However, predators were not attracted more to healthy, real caterpillars than to “untreated” artificial ones. We conclude that using artificial caterpillars does not underestimate predation pressure by this carabid on healthy caterpillars.

Non-cultivated areas in agricultural landscapes can substantially contribute to biodiversity. Therefore, to examine the role of tree-line hedges in supporting arthropod diversity in an agricultural landscape, we sampled carabid beetles in three replicates of a native deciduous (hawthorn, Crataegus mono-gyna), a non-native deciduous (rowan, Sorbus intermedia), and a non-native coniferous (spruce, Picea spp.) hedge in Jytland, Denmark. We hypothesised that hedgerows with deciduous trees harbour more diverse carabid assemblages than hedges composed of non-native trees. The number of carabid individuals and species was highest in the hawthorn hedges and significantly lower in rowan and spruce. This was caused by the presence of forest specialist species. Differences in the number of the grassland and the cropland specialist ground beetle individuals and species were not statistically significant among the hedges. Litter depth and the density of herbs and grasses negatively, while hedge width positively influenced carabid diversity. Overall, hedges composed of the native, deciduous hawthorn were superior to ones composed of the non-native rowan, and especially to coniferous ones to conserve and maintain carabid diversity in this cultivated Danish landscape.

Most edges are anthropogenic in origin, but are distinguishable by their maintaining processes (natural vs. continued anthropogenic interventions: forestry, agriculture, urbanization). We hypothesized that the dissimilar edge histories will be reflected in the diversity and assemblage composition of inhabitants. Testing this “history‐based edge effect” hypothesis, we evaluated published information on a common insect group, ground beetles (Coleoptera: Carabidae) in forest edges. A meta‐analysis showed that the diversity‐enhancing properties of edges significantly differed according to their history. Forest edges maintained by natural processes had significantly higher species richness than their interiors, while edges with continued anthropogenic influence did not. The filter function of edges was also essentially different depending on their history. For forest specialist species, edges maintained by natural processes were penetrable, allowing these species to move right through the edges, while edges still under anthropogenic interventions were impenetrable, preventing the dispersal of forest specialists out of the forest. For species inhabiting the surrounding matrix (open‐habitat and generalist species), edges created by forestry activities were penetrable, and such species also invaded the forest interior. However, natural forest edges constituted a barrier and prevented the invasion of matrix species into the forest interior. Preserving and protecting all edges maintained by natural processes, and preventing anthropogenic changes to their structure, composition, and characteristics are key factors to sustain biodiversity in forests. Moreover, the increasing presence of anthropogenic edges in a landscape is to be avoided, as they contribute to the loss of biodiversity. Simultaneously, edges under continued anthropogenic disturbance should be restored by increasing habitat heterogeneity.

Urbanisation results in a marked modification of habitats and influences several ecological processes, some of which give rise to beneficial ecological services. Natural pest control, the effect of predators on prey is one of such services. We quantified changes in the incidence of predation with increasing levels of urbanisation using artificial caterpillars made of green plasticine. Potential predators can be identified by the "attack marks" they leave on these artificial caterpillars. We conducted this study from May to October 2010 around the city of Sorø (Zealand, Denmark), in forests along an urbanisation gradient (rural-suburban-urban). Artificial caterpillars were placed on the ground in order to obtain an estimate of the incidence of predation at ground level. Half (50%) of the 1398 caterpillars were "attacked" and 28.8% of the bites were those of chewing insects. We attributed the majority of these to carabids, the most common group of ground-active arthropods. Chewing insects exerted the greatest predation pressure in the original forest (52.1%), with lower values recorded in the suburban (10.1%) and urban (16.4%) forest fragments. Ants were responsible for only 4.7% of the attacks in forest, 11.3% in suburban and 16.4% in urban forest fragments. Mammals exerted the highest predation pressure in suburban habitats (22.2% vs. 4.9% in forest, and 8.1% in urban forest fragments).

BACKGROUND The two common whitefly species, Bemisia tabaci (Gennadius) MEAM1 and Trialeurodes vaporariorum (Westwood), often co-occur on their host plants. The effect of host plant occupation by one species on later-arriving conspecific individuals or on the other competing species was examined. RESULTS Resource preoccupied by T. vaporariorum had mostly negative effects on the life history parameters of later-arriving conspecifics. Red-eyed nymph and immature survival of T. vaporariorum decreased when resource was preoccupied by conspecifics, irrespective of the previous occupation scenario. However, resource preoccupied by T. vaporariorum had only minor detrimental effects on the performance of later-arriving B. tabaci MEAM1. In the opposite colonisation sequence, previous occupation by B. tabaci MEAM1 had no significant effects on the life history parameters of later-arriving conspecifics, but severe detrimental effects were observed on the performance of later-arriving T. vaporariorum. Total immature survival of T. vaporariorum decreased in both weak and strong previous occupation situations by B. tabaci MEAM1. CONCLUSION The interspecific interactions between B. tabaci MEAM1 and T. vaporariorum were asymmetric, with B. tabaci MEAM1 being the superior competitor. This superiority could partially explain the rapid spread of B. tabaci MEAM1 in China. © 2013 Society of Chemical Industry

The continued decline in farmland biodiversity in Europe despite substantial funding for agri-environment schemes (AES) has prompted calls for more effective biodiversity conservation measures. The current AES regime allows for both holistic measures, such as organic farming, that broadly target the agricultural environment and biodiversity-specific measures, such as flowering fields, but little is known of their relative efficacies. To address this gap, we studied carabids in 48 arable fields that presented four crop types under different management practices along a gradient of landscape complexity: (a) conventionally managed crop (winter wheat), (b) biodiversity-specific AES under conventional management (sown flowering field), (c) organically managed mono-crop (winter spelt) and (d) organically managed lentil-mixedcrop (lentil intercropped with cereal or camelina). For these crop-use types, we compared functional diversity of carabid assemblages at the edge and center of the fields. Using pitfall traps, we collected more than 55,000 carabids of 95 species over two years. We characterized diversity using community weighted means and functional divergence of three ecological traits – body size, feeding type, and flight ability. Conventional flowering fields and organic winter spelt, but not organic spring sown lentil-mixed-crop, increased the proportion of plant-feeding carabids; moreover, trait characteristics and their divergences were most affected by field edges, with smaller, less carnivorous and more flight-enabled carabid assemblages found there than in the center. Divergence of body size and feeding type but not of flight ability was larger at the field edges than centres. Surrounding landscape complexity did not affect carabid traits. We conclude that future AES policy should avoid strict decisions between biodiversity specific- and holistic measures. Instead, priority should be given to a diversity of different measures, targeting the enhancement of edge habitats as well as productive and non-productive measures.

Sentinel prey can provide a direct, quantitative measure of predation under field conditions. Live sentinel prey provides more realistic data but rarely allows the partitioning of the total predation pressure; artificial prey is less natural but traces left by different predators are identifiable, making it suitable for comparative studies. We reviewed the available evidence of the use of both types of invertebrate sentinel prey. Fifty-seven papers used real prey, usually measuring predation on a focal (often pest) species, with studies overwhelmingly from North America. The median predation was 25.8% d

In China, two invasive pests, Bemisia tabaci MEAM1 (Gennadius) and Frankliniella occidentalis (Pergande), often co-occur with the native pest, Aphis gossypii (Glover), on plants of Malvaceae and Cucurbitaceae. All three are preyed on by the native ladybird, Harmonia axyridis (Pallas); however, the native predator might be expected to prefer native prey to the exotic ones due to a shared evolutionary past. In order to clarify whether the presence of native prey affected the consumption of these two invasive species by the native predator, field-cage experiments were conducted. A duplex qPCR was used to simultaneously detect both non-native pests within the gut of the predator. H. axyridis readily accepted both invasive prey species, but preferred B. tabaci. With all three prey species available, H. axyridis consumption of B. tabaci was 39.3 +/- 2.2% greater than consumption of F. occidentalis. The presence of A. gossypii reduced (by 59.9% on B. tabaci, and by 60.6% on F. occidentalis), but did not stop predation on the two exotic prey when all three were present. The consumption of B. tabaci was similar whether it was alone or together with A. gossypii. However, the presence of aphids reduced predation on the invasive thrips. Thus, some invasive prey may be incorporated into the prey range of a native generalist predator even in the presence of preferred native prey.

Sampling effort in pitfall trapping sessions is routinely calculated as a product of trap numbers and time period, expressed in units of trap-days or trap-weeks. This assumes that these two components contribute equally to the catch, so that the catch from 2n traps run for z days should be equivalent to the catch of n traps run for 2z days. We tested this equivalence relationship by comparing two pitfall trapping sessions, representing an identical trapping effort, performed in the same habitat (an apple orchard in Hungary), using the same pitfall trapping arrangement. The Time Series session had 20 traps operating for 20 weeks (400 trap-weeks), while the Spatial Series session had 100 traps operating for 4 weeks (400 trap-weeks). The Time Series session caught 1265 individuals of 44 species, while the Spatial Series session had fewer (757) individuals but 52 species. The virtual structure of the two carabid assemblages was different, although the major species were the same. Rarefaction curves clearly show that the Spatial Series indicated the presence of a significantly more species-rich ground beetle assemblage than the Time Series. The “common currency” for trapping effort needs to be re-examined because its two components, number of traps and length of operation do not contribute to the final catch in the same way. This has an important consequence for the design of biodiversity monitoring: trapping effort allocation for monitoring may be better when the number of traps is at the possible maximum and the time of sampling shortened rather than the other way around.

‘Carabidologists do it all’ (Niemelä 1996a) is a phrase with which most European carabidologists are familiar. Indeed, during the last half a century, professional and amateur entomologists have contributed enormously to our understanding of the basic biology of carabid beetles. The success of the field is in no small part due to regular European Carabidologists’ Meetings, which started in 1969 in Wijster, the Netherlands, with the 14th meeting again held in the Netherlands in 2009, celebrating the 40th anniversary of the first meeting and 50 years of long-term research in the Dwingelderveld. This paper offers a subjective summary of some of the major developments in carabidology since the 1960s. Taxonomy of the family Carabidae is now reasonably established, and the application of modern taxonomic tools has brought up several surprises like elsewhere in the animal kingdom. Progress has been made on the ultimate and proximate factors of seasonality and timing of reproduction, which only exceptionally show non-seasonality. Triggers can be linked to evolutionary events and plausibly explained by the “taxon cycle” theory. Fairly little is still known about certain feeding preferences, including granivory and ants, as well as unique life history strategies, such as ectoparasitism and predation on higher taxa. The study of carabids has been instrumental in developing metapopulation theory (even if it was termed differently). Dispersal is one of the areas intensively studied, and results show an intricate interaction between walking and flying as the major mechanisms. The ecological study of carabids is still hampered by some unresolved questions about sampling and data evaluation. It is recognised that knowledge is uneven, especially concerning larvae and species in tropical areas. By their abundance and wide distribution, carabid beetles can be useful in population studies, bioindication, conservation biology and landscape ecology. Indeed, 40 years of carabidological research have provided so much data and insights, that among insects - and arguably most other terrestrial organisms - carabid beetles are one of the most worthwhile model groups for biological studies.