@misc{MelcherWeberBirkhoferetal., author = {Melcher, Anja Carina and Weber, Sven and Birkhofer, Klaus and Harms, Danilo and Krehenwinkel, Henrik}, title = {To pool or not to pool : pooled metabarcoding does not affect estimates of prey diversity in spider gut content analysis}, series = {Ecological Entomology}, volume = {49}, journal = {Ecological Entomology}, number = {6}, issn = {0307-6946}, doi = {10.1111/een.13382}, pages = {768 -- 778}, abstract = {1. Gut content metabarcoding has provided important insights into the food web ecology of spiders, the most dominant terrestrial arthropod predators. In small invertebrates, like spiders, gut content analysis is often performed on whole body DNA extracts of individual predators, from which prey sequences are selectively enriched and sequenced. 2. Since many spider species are generalist predators, large numbers of samples comprising individual spider specimens must be analysed to recover an exhaustive image of a spider species' prey spectrum, which is costly and time-consuming. 3. Pooled processing of bulk samples of multiple specimens has been suggested to reduce the necessary workload and cost while still recovering a representative estimate of the prey diversity. However, it is still unclear if pooling approaches lead to bias in recovering the prey spectrum and if the results are comparable with data from individually processed spiders. 4. Here, we test the effects of metabarcoding pooled spider gut content on the recovered taxonomic diversity and composition of prey. Using a newly adapted primer pair, which efficiently enriches COI barcode sequences of diverse arthropod prey groups while suppressing spider amplification, we test if pooling leads to reduced taxonomic diversity or skewed estimates of prey composition. 5. Our results show that pooling and individual processing recover highly correlated taxonomic diversity and composition of prey. The only exception are very rare prey items which were less well recovered by pooling. Our results support pooling as a cost-effective and time-efficient approach to recover the diet of generalist predators for population-level studies of spider trophic interactions.}, language = {en} } @misc{KoberBirkhoferGlemnitz, author = {Kober, Klarissa and Birkhofer, Klaus and Glemnitz, Michael}, title = {High soil moisture promotes the emergence of ground beetles and spiders from soils in wheat fields}, series = {Basic and Applied Ecology}, journal = {Basic and Applied Ecology}, number = {80}, issn = {1439-1791}, doi = {10.1016/j.baae.2024.09.001}, pages = {72 -- 80}, abstract = {Promoting arthropods in agricultural landscapes can contribute substantially to stop their decline and enhance pest control. Higher soil moisture and the presence of field margins can increase the abundance of arthropods in agricultural landscapes and influence their distribution within crop fields. However, little is known about the influence of soil moisture and distance from field margins on the overwintering of arthropods in arable fields. We investigated the influence of soil moisture and distance from a field margin on the numbers of arthropods, ground beetles and spiders emerging from soil in winter wheat fields. We established transects in winter wheat fields away from two different types of field margins: (i) around small standing water bodies (kettle holes) to capture a wide range of soil moisture values and (ii) other semi-natural landscape elements. At three distances (1 m, 20 m, 50 m), we sampled arthropods with emergence traps and measured soil moisture between March and June. We found that soil moisture had a positive effect on the emergence numbers of arthropods in general and ground beetles and spiders in particular. Distance from field margins generally had negative effects on the emergence numbers of ground beetles, but positive effects on the emergence numbers of spiders. Emergence numbers and soil moisture content did not differ significantly between the two types of field margins. The high emergence numbers inside the fields indicate that arable fields are important overwintering habitats for beneficial arthropods. Proper management of arable soils to promote soil water holding capacity and soil moisture content may have the added benefit of promoting the production of beneficial natural enemies from local soils.}, language = {en} } @misc{MenaresSaizSchenketal., author = {Menares, Esteban and Sa{\´i}z, Hugo and Schenk, No{\"e}lle V. and Garcia de la Riva, Enrique and Krauss, Jochen and Birkhofer, Klaus}, title = {Co-occurrence patterns do not predict mutualistic interactions between plant and butterfly species}, series = {Ecology and Evolution}, volume = {14}, journal = {Ecology and Evolution}, number = {11}, issn = {2045-7758}, doi = {10.1002/ece3.70498}, pages = {13}, abstract = {Biotic interactions are crucial for determining the structure and dynamics of communities; however, direct measurement of these interactions can be challenging in terms of time and resources, especially when numerous species are involved. Inferring species interactions from species co-occurrence patterns is increasingly being used; however, recent studies have highlighted some limitations. To our knowledge, no attempt has been made to test the accuracy of the existing methods for detecting mutualistic interactions in terrestrial ecosystems. In this study, we compiled two literature-based, long-term datasets of interactions between butterflies and herbaceous plant species in two regions of Germany and compared them with observational abundance and presence/absence data collected within a year in the same regions. We tested how well the species associations generated by three different co-occurrence analysis methods matched those of empirically measured mutualistic associations using sensitivity and specificity analyses and compared the strength of associations. We also checked whether flower abundance data (instead of plant abundance data) increased the accuracy of the co-occurrence models and validated our results using empirical flower visitation data. The results revealed that, although all methods exhibited low sensitivity, our implementation of the Relative Interaction Intensity index with pairwise null models performed the best, followed by the probabilistic method and Spearman's rank correlation method. However, empirical data showed a significant number of interactions that were not detected using co-occurrence methods. Incorporating flower abundance data did not improve sensitivity but enhanced specificity in one region. Further analysis demonstrated incongruence between the predicted co-occurrence associations and actual interaction strengths, with many pairs exhibiting high interaction strength but low co-occurrence or vice versa. These findings underscore the complexity of ecological dynamics and highlight the limitations of current co-occurrence methods for accurately capturing species interactions.}, language = {en} } @misc{BucherBataryBaudryetal., author = {Bucher, Roman and Batary, P{\´e}ter and Baudry, Julia and Beaumelle, L{\´e}a and Čerevkov{\´a}, Andrea and Garcia de la Riva, Enrique and Dirilgen, Tara and Gall{\´e}, Robert and Kesse-Guyot, Emmanuelle and Rembiałkowska, Ewa and Rusch, Adrien and Stanley, Dara A. and Ulrich, Werner and Birkhofer, Klaus}, title = {Functional diversity of ground beetles improved aphid control but did not increase crop yields on European farms}, series = {Ecological Applications}, volume = {2024}, journal = {Ecological Applications}, issn = {1051-0761}, doi = {10.1002/eap.3035}, pages = {16}, abstract = {Land-use intensification is often associated with a decline in functional diversity, potentially undermining the provision of ecosystem services. However, how changes in traits affect ecosystem processes remains poorly understood. Variation in trait values among species in a community may drive ecosystem processes. Alternatively, the mass ratio hypothesis proposes that trait values of the dominant species in a local community are related to ecosystem processes. Using data from 159 farms in six European countries, we quantified the impact of local and landscape-level land-use intensity on ground beetles as pest control agents. We then assessed the extent to which functional diversity and community-weighted mean trait values relate to pest control and cereal yield. In addition, we assessed how the responses to land use and the effects of different species on pest control and yield varied with their traits to compare the relative impact of the traits studied. Functional diversity of ground beetles improved aphid removal, but did not translate into higher crop yields. Pest control of aphids was enhanced by a higher proportion of smaller, mobile ground beetles with a preference for the vegetation layer. Smaller, predatory ground beetles in communities improved crop yield. The magnitude of responses to land-use intensification and the effects on pest control and yield were more strongly influenced by body size than other traits. Our study provides evidence that reduced management intensity can improve pest control by supporting small-sized, macropterous ground beetles. In contrast to the claims of ecological intensification, our joint analysis of the direct effects of land use on yield and indirect effects via functional diversity of ground beetles and pest control suggests that ecosystem services by ground beetles cannot compensate for the yield gap due to a reduction in land-use intensity.}, language = {en} } @misc{FengArvidssonDjoudietal., author = {Feng, Lanya and Arvidsson, Fredrik and Djoudi, El Aziz and Birkhofer, Klaus}, title = {Terrestrial generalist predators have larger isotopic niches but rely less on aquatic prey at a natural compared to a post-mining lakeshore}, series = {Food webs}, volume = {41}, journal = {Food webs}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-2496}, doi = {10.1016/j.fooweb.2024.e00368}, pages = {1 -- 9}, abstract = {The flooded pits from former opencast mining (post-mining lakes) are young aquatic ecosystems often with low primary productivity due to the high acidity. The limited availability of nutrients and simplified aquatic food webs in these artificial lakes may affect the matter fluxes towards food webs in adjacent terrestrial habitats. To understand the impact of emerging prey from a post-mining lake on terrestrial food webs and associated arthropod communities, we compared the emergence and activity of arthropods as well as the isotopic niches of generalist predators and their potential prey between lakeshores of a post-mining and a natural lake. We used aquatic and terrestrial emergence tents to sample potential prey that emerged locally (Collembola and Diptera) and pitfall traps to sample terrestrial arthropod predators (Carabidae and Araneae) from lakeshores. Community and stable isotope (δ13C and δ15N) analyses were performed to compare diversity and isotopic niches of generalist arthropod predators between the natural and post-mining lakeshores. The number of emerging aquatic and terrestrial prey did not differ significantly between lakes, but the δ15N values of aquatic emerging dipterans differed between the two lakes. Predator community diversity did not differ significantly between lakeshores, but generalist predator species from the natural lakeshore generally had larger isotopic niche sizes than the same species at the post-mining lakeshore indicating a more diverse diet. Additional estimates of diet composition suggest that predators at the natural lakeshore utilized aquatic prey to a lesser degree than at the post-mining lake, but still had a more diverse diet.}, language = {en} } @misc{GavinCentolSerranoCarneroMontserratetal., author = {Gav{\´i}n-Centol, Mar{\´i}a Pilar and Serrano-Carnero, Diego and Montserrat, Marta and Balanzategui, I{\~n}aki and Scheu, Stefan and Truu, Jaak and Birkhofer, Klaus and S{\´a}nchez-Moreno, Sara and Moya-Lara{\~n}o, Jordi}, title = {Drought impairs detritivore feeding activity more strongly in northern than in southern European latitudes}, series = {Soil biology and biochemistry}, volume = {199}, journal = {Soil biology and biochemistry}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0038-0717}, doi = {10.1016/j.soilbio.2024.109594}, pages = {1 -- 15}, abstract = {Soil detritivores play key roles in decomposition processes closely related to ecosystem services. Drought and soil organic carbon depletion due to agricultural management are detrimental to soil biodiversity, but their interactive effects on soil biota and associated processes have not been thoroughly investigated. In 2018, we used rain-out shelters to experimentally induce drought in wheat fields of contrasting levels of organic carbon in Sweden, Germany and Spain. That year Europe experienced a climatic dipole, with exceptionally severe droughts in northern latitudes. We assessed the feeding activity of soil detritivores by bait-lamina tests, and measured several abiotic and biotic soil parameters. In the peak of the dipole drought (summer) southern fields had the driest soils. Nonetheless, detritivore feeding activity responded to the experimental drought by shifting to deeper soil layers there. Low soil organic carbon (SOC) levels exacerbated the latter effect. However, in this same period, feeding activity in northern and central Europe was two orders of magnitude lower than in the south, and failed to respond to either the experimental treatment and/or SOC levels. Using mixed-effects longitudinal random forests, we detected various candidate drivers of detritivore feeding activity: soil moisture, phosphorus content, bacteria and nematodes. Different bacterial taxa were associated to detritivory in each country, but their potential influence was pervasive. Thus, our results suggest that drought had adverse effects on detritivore feeding, which were exacerbated northwards due to the climatic dipole. Increased SOC levels mitigated drought effects only in southern soils. Regional adaptation of soil biota to aridity could explain the response of detritivores in southern Europe to drought. Machine learning algorithms arise as useful tools for exploring potential drivers relating biodiversity to soil processes. Overall, future research on the effects of drought on soil biodiversity and processes will be key for tackling climate change impacts in terrestrial ecosystems.}, language = {en} } @misc{MichalkoBirkhoferTraugottetal., author = {Michalko, Radek and Birkhofer, Klaus and Traugott, Michael and Jonsson, Mattias}, title = {Negative intraguild interactions drive niche variation in arthropod predators}, series = {Entomologia generalis}, volume = {44}, journal = {Entomologia generalis}, number = {3}, publisher = {Schweizerbart}, address = {Stuttgart}, issn = {2363-7102}, doi = {10.1127/entomologia/2024/2282}, pages = {525 -- 534}, abstract = {The niche variation hypothesis states that the population niche width expands with increasing interindividual differences in prey utilization (i.e., individual dietary specialization). The main ecological drivers forming this relationship include a) ecological opportunity, b) food limitation and exploitative competition, and c) intraguild interference. Only a limited number of empirical studies have tested the impact of these drivers on the niche variation-width relationship and focused only on vertebrates. Using molecular gut content analysis, we investigated how prey diversity (proxy for ecological opportunity), prey abundance (proxy for exploitative competition / food-limitation), and activity density of guild members (proxy for intraguild interference) affect the short-term individual dietary specialization and consequently the population niche width in local communities of 13 species of predatory beetles and spiders. The study took place in 10 spring barley fields in Sweden in 2011. We found that the niche variation and consequently the average population niche width of the spe- cies in the predator community decreased with prey abundance but increased with activity density of guild members. The results indicate that intraguild interference and exploitative competition / food limitation increased dietary variation. The increased diet variation led to the observed population diet expansion. Our results support the niche variation hypothesis and, in contrast to the traditional view, show that negative intraguild interactions may act as a diversifying force.}, language = {en} } @misc{KocsisSchnerch, author = {Kocsis, Timea and Schnerch, Benjamin}, title = {First record of Diplocephalus graecus (O. Pickard- Cambridge, 1873) in the Netherlands (Araneae, Linyphiidae)}, series = {Nieuwsbrief spined}, volume = {41}, journal = {Nieuwsbrief spined}, publisher = {European Invertebrate Survey}, address = {Leiden}, issn = {0926-0781}, pages = {7 -- 9}, abstract = {The sheet weaver Diplocephalus graecus O. Pickard-Cambridge, 1873 is a common species in the holomediterranean region, but has been extending its northward distribution in the recent two decades. Our recording of the species marks the northernmost distribution of the species as of yet. With our recording, the number of species belonging to the Linyphiidae family in the Netherlands has been raised to 238.}, language = {en} } @misc{SchnerchBucherDjoudietal., author = {Schnerch, Benjamin and Bucher, Roman and Djoudi, El Aziz and Hossain, Mohammad and Bapfubusa Niyibizi, Ingrid Aline and Birkhofer, Klaus}, title = {Growth stage, management and habitat influence the taxonomic and functional composition of arthropod communities in apple orchards}, series = {Agriculture, ecosystems \& environment}, volume = {394}, journal = {Agriculture, ecosystems \& environment}, publisher = {Elsevier BV}, address = {Amsterdam}, doi = {10.1016/j.agee.2025.109901}, pages = {1 -- 13}, abstract = {Apples are the most cultivated fruits in temperate regions, and their production relies on heavy use of synthetic pesticides, causing major environmental problems and the loss of biodiversity. Pests in tree canopies are commonly controlled by the use of synthetic pesticides, but habitat manipulations in orchard alleys are an alternative practice to promote natural pest control services. Integrated pest management (IPM) and organic production methods are considered to be more sustainable and environmentally friendly than conventional production, but the knowledge of the differences between arthropod communities in IPM and organic apple orchards differ from each other is limited. Therefore, we sampled alley and canopy arthropod communities in eight orchards under IPM and eight organic apple orchards, respectively, during three sampling dates in the apple growing season. Our results show that seasonal effects predominantly shape the taxonomic composition and abundance of arthropod community, especially within canopy habitats, while management effects are context-dependent for several taxonomic groups. The species composition of spider communities in canopy habitats differed significantly between management systems depending on dates, with some common species being more abundant in IPM than in organic orchards later in the season. The functional diversity of spider communities was significantly lower in the orchard alleys than in tree canopies, and increased in alley, but decreased in canopy habitats over time. Communities in IPM orchards had a higher proportion of spiders with ballooning ability, indicating that aerial dispersal is more common for spiders in IPM compared to organic orchards. The results of this study highlight the context dependency of management effects on the taxonomic and functional composition of arthropod communities, as these are likely to be most pronounced at certain times of the growing season and in certain habitats. Functional diversity and trait composition were more sensitive to management differences than taxonomic composition. Our results therefore emphasise the need to consider both taxonomic and functional metrics, and to incorporate seasonal and habitat considerations, when assessing the effects of sustainable management practices on arthropod communities in the future}, language = {en} } @misc{BucherMasson, author = {Bucher, Roman and Masson, Aline M.}, title = {Black garden ants reduce aphid predation by native and invasive ladybirds}, series = {Ecological entomology}, journal = {Ecological entomology}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {1365-2311}, doi = {10.1111/een.70033}, pages = {1 -- 4}, abstract = {1. Intraguild interference between predators can hamper top-down regulation. For example, aphid-tending ants often defend their mutualistic partners against antagonists. Greater ant aggression against native ladybirds compared to non-native ladybirds might benefit the non-native predator, due to predator-predator na{\"i}vet{\´e}. As a consequence, non-native ladybirds are expected to consume more aphids and might thus outcompete native ladybirds. 2. We established microcosms with a bean plant (Vicia faba) infested with black bean aphids (Aphis fabae). The microcosms were divided into the following treatments: no ants, aphids tended by common red ants (Myrmica rubra) and aphids tended by black garden ants (Lasius niger). We added either a native ladybird (Coccinella septempunctata) or an invasive ladybird (Harmonia axyridis) to the microcosms. We compared deterrence of ladybirds from plant-based aphids by ants and the number of aphids remaining at the end of the experiment. 3. Our results indicate that L. niger, but not M. rubra, deterred ladybirds from the plant and strongly increased the number of remaining aphids in the presence of both ladybird species. In contrast to our expectation, more aphids tended to remain in the presence of H. axyridis and M. rubra compared to the C. septempunctata and M. rubra combination. 4. We conclude that intraguild interference can weaken top-down control and depends on the aggressiveness and potentially prey consumption of competing species. However, we found no support for the predator-predator na{\"i}vet{\´e} hypothesis suggesting that non-native predators would be released from intraguild interference and thus consume more prey.}, language = {en} } @misc{BapfubusaNiyibiziSchnerchDjoudietal., author = {Bapfubusa Niyibizi, Ingrid Aline and Schnerch, Benjamin and Djoudi, El Aziz and Birkhofer, Klaus}, title = {Aphid proliferation in orchard alleys and canopy predator aggregation in eastern German apple orchards}, series = {Agricultural and forest entomology}, volume = {27}, journal = {Agricultural and forest entomology}, number = {4}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {1461-9563}, doi = {10.1111/afe.12699}, pages = {742 -- 754}, abstract = {1. European apple (Malus domestica) orchards face persistent threats from aphid infestations, which can severely compromise fruit yields. 2. In this study, we compared aphid communities in two microhabitats (tree canopy and orchard alley) in commercial apple orchards under organic and integrated pest management (IPM), in relation to aphidophagous predator abundance at three stages of the growing season: early fruit development, fruit maturity and post-harvest. 3. We sampled eight organic and eight IPM apple orchards in eastern Germany using standardised canopy beating of apple trees and suction sampling in the orchard alleys. 4. Our results indicate no significant differences in aphid infestation between organic and IPM orchards, regardless of the sampled microhabitat. However, aphid communities in the tree canopy of organic orchards exhibited greater evenness across species than those of IPM orchards. Eriosoma lanigerum consistently dominated canopy aphid communities across both management systems, highlighting the need for targeted management practices for this pest. Additionally, aphidophagous predator abundance in the tree canopy increased over time and showed a positive association with aphid abundance. Aphid community structure varied significantly across sampling periods and microhabitats. Differences between organic and IPM orchards were observed during the early fruit development phase in orchard alleys, with higher levels of infestation in organic orchards. Aphid taxa such as Macrosiphum euphorbiae, Dysaphis spp., Aphis spiraecola and Rhopalosiphum insertum contributed to these differences. 5. Our findings provide a better understanding of the temporal dynamics of aphid communities in apple orchards in eastern Germany, highlighting the importance of microhabitats and host plant phenology.}, language = {en} } @misc{BirkhoferEkroosMaderetal., author = {Birkhofer, Klaus and Ekroos, Johan and Mader, Viktoria and Tschumi, Matthias and Wu, Ai-ping and Smith, Henrik G.}, title = {Taxonomy, habitat and conservation status explain the diet composition of insectivorous birds in Europe}, series = {Biological conservation}, volume = {313}, journal = {Biological conservation}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0006-3207}, doi = {10.1016/j.biocon.2025.111566}, pages = {1 -- 11}, abstract = {Populations of European birds and insects are declining, with consequences for trophic interactions. Insectivorous birds are particularly vulnerable to losses of arthropods, yet the factors shaping their diet composition remain insufficiently understood. We conducted a quantitative review of the arthropod diets of 94 European insectivorous bird species and assessed how diet richness and composition relate to taxonomy, developmental stage, climate, conservation status, habitat, migration status, sampling intensity, and methodological approach. Taxonomy, habitat and conservation status (both population trend over time and current status) were the primary predictors of diet richness and composition. Species of population concern in Europe relied more on Coleoptera and Orthoptera prey, while species with declining population trends and species in agricultural, artificial and semi-natural habitats showed strong dependence on Coleoptera prey. Species in forests and of global population concern had a higher percentage of Arachnida prey, while birds in inland water habitats relied on Diptera prey. Anthropogenic activities such as the use of insecticides and changes in land use in agricultural and forest habitats negatively impact the abundance and diversity of arthropods, including Coleoptera and Arachnida. These declines will cascade up the food chain, ultimately diminishing both common and threatened bird species by limiting their prey. Species of global conservation concern may be particularly at risk, as they exhibit the lowest prey taxonomic richness. It is therefore crucial that future legislation and policy interventions consider these indirect impacts on bird diets, as these vulnerable species are at high risk of further losses in arthropod prey.}, language = {en} } @misc{ArvidssonBirkhofer, author = {Arvidsson, Fredrik and Birkhofer, Klaus}, title = {The value of public databases for our knowledge of national spider biodiversity compared to a long-term scientific monitoring project.}, series = {Insect conservation and diversity}, volume = {19}, journal = {Insect conservation and diversity}, number = {1}, publisher = {Wiley}, issn = {1752-4598}, doi = {10.1111/icad.70024}, pages = {228 -- 239}, abstract = {Citizen science can be a valuable tool for monitoring changes in biodiversity, especially for less frequently studied taxonomic groups such as spiders. These collaborative projects between scientists and private citizens can provide a cost-effective means of collecting large data sets, while also raising awareness of environmental and sustainability issues. A comparison of two public databases ( iNaturalist and the Swedish biodiversity database Artportalen ) with a national scientific study using malaise traps (Swedish Malaise Trap Project, SMTP) sheds light on their individual and combined contribution to our understanding of spider biodiversity and geographical distribution in Sweden. iNaturalist is an important global platform for mobilising public participation in biodiversity research. While widely used internationally, its coverage in Sweden is relatively limited and tends to over-represent species that are easy to spot and often observed in densely populated areas. Artportalen includes a large body of observations contributed through citizen science. It offers wide species coverage, supported by higher expert input. Nevertheless, it exhibits sampling bias towards species that are diurnal and common in more populated areas. Projects based on large-scale sampling schemes such as SMTP therefore make essential contributions to our understanding of the occurrence of species, especially for rare and uncommon species or species with cryptic life histories. Records are, however, limited in distribution to the pre-defined sample locations. Given the more resource-intensive nature of traditional scientific surveys, a combined approach that integrates citizen science data with scientific sampling offers the most robust and comprehensive means of assessing biodiversity.}, language = {en} } @misc{AlfeusHeringDjoudietal., author = {Alfeus, Martha and Hering, Robert and Djoudi, El Aziz and Angombe, Simon and Birkhofer, Klaus}, title = {Encroaching shrub species alter arthropod community composition and trophic structure in southern African rangeland ecosystems}, series = {Agriculture, ecosystems \& environment}, volume = {396}, journal = {Agriculture, ecosystems \& environment}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {1873-2305}, doi = {10.1016/j.agee.2025.110016}, pages = {1 -- 10}, abstract = {Bush encroachment is rapidly transforming savannah and grassland ecosystems in southern Africa, altering vegetation structure and ecosystem functioning, while reducing rangeland productivity. Despite these shifts, its effects on local biodiversity, particularly arthropod communities remain understudied. This study evaluated the arthropod communities within areas dominated by three major encroaching shrub species in southern Africa: Dichrostachys cinerea, Senegalia mellifera and Terminalia sericea. Arthropods were sampled in northcentral Namibia using pitfall traps (ground-dwelling), pan traps (flying), and shrub beating (canopy-dwelling) during both wet and dry seasons. Arthropod community composition differed significantly among encroaching species, primarily driven by canopy-dwelling arthropods. Senegalia mellifera supported distinct communities distinguished by the exclusive presence of woodlice (Isopoda), while, D. cinerea and T. sericea plots hosted distinct taxa, including Caelifera, Mantodea and Strepsiptera. Also the trophic composition differed among shrubs, with omnivores dominating S. mellifera and phytophagous arthropods dominating D. cinerea plots. Formicidae and Collembola were numerically dominant across all plots. Brachycera, Curculionidae and Collembola were highly sensitive to local environmental variation, indicating their potential as bio-indicators for monitoring shrub encroachment and effectiveness of management interventions. Overall arthropod abundance positively correlated with ground cover, while taxonomic diversity showed a negative relationship. Therefore, conservation efforts in bush encroached areas should promote vegetation management strategies that enhance structural heterogeneity to support greater arthropod diversity. Our findings provide a key baseline on how encroaching shrub species affect arthropods, highlighting the need to consider invertebrate biodiversity in de-bushing efforts in southern Africa, which have traditionally focused on rangeland productivity over ecological impacts.}, language = {en} } @misc{BirkhoferWaetzoldRemelgadoetal., author = {Birkhofer, Klaus and W{\"a}tzold, Frank and Remelgado, Ruben and Addison, Pia and Aigbedion-Atalor, Pascal and Cord, Anna F. and Ekesi, Sunday and Mutamiswa, Reyard and Rwomushana, Ivan}, title = {A framework for multidimensional management of invasive alien insect pests in sub-Saharan Africa}, series = {Journal of applied entomology}, journal = {Journal of applied entomology}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0931-2048}, doi = {10.1111/jen.70060}, pages = {1 -- 10}, abstract = {Invasive alien insect pests pose a significant threat to achieving sustainable food systems in sub-Saharan Africa, where reliance on synthetic pesticides has led to unsustainable practices due to high costs and health and environmental risks. This article presents a multidimensional framework for managing invasive alien insect pests in sub-Saharan Africa, specifically directed at researchers, policymakers, non-governmental organisations and other institutions responsible for invasive pest management as well as extension services for farmers. Invasive pests, such as the Oriental fruit fly and the fall armyworm, and a highly damaging native species for comparison are central to the framework. The framework considers the environmental, socio-economic, and regulatory dimensions of pest management decisions. It reviews different control strategies used against invasive alien pests, highlighting their limitations and environmental impacts. By considering farmer characteristics, institutional support, market demands, and regulatory policies, the article emphasises the need for integrated pest management approaches. The aim is to contribute to the development of sustainable, effective pest management strategies that will ensure long-term agricultural productivity and food security in sub-Saharan Africa.}, language = {en} } @misc{DjoudiAmosseAvironetal., author = {Djoudi, El Aziz and Amoss{\´e}, Ewen and Aviron, St{\´e}phanie and Birkhofer, Klaus and Libereau, Benjamin and Plantegenest, Manuel and P{\´e}tillon, Julien}, title = {Multi‑trophic arthropod communities modulated by local farming system and landscape heterogeneity}, series = {Landscape ecology}, volume = {41}, journal = {Landscape ecology}, publisher = {Springer Nature}, address = {Dordrecht}, issn = {1572-9761}, doi = {10.1007/s10980-026-02298-y}, pages = {1 -- 14}, abstract = {Context Organic farming is increasingly used worldwide in recent decades, but the role of this farming system in shaping the trophic structure of arthropod communities remains poorly understood, especially at different spatial scales. Therefore, the contribution of landscape heterogeneity in shaping arthropod's trophic guilds remain understudied. Objectives In this study, we assessed how the evenness, the abundance and the taxonomic richness of arthropod trophic groups were shaped by the local farming system, landscape heterogeneity (including the percentage of semi-natural habitats and organic fields), and their interaction. Methods Arthropod's trophic guilds (ground and vegetation-dwelling) were sampled in 20 spatial independent pairs of conventional (CF) and organic (OF) fields located in Brittany (Western France) by using pitfall traps and sweep nets replicated in time and space. Results A total of 95,822 arthropods belonging to 197 taxonomic groups were sampled. Farming system has a strong overall positive effect on the community structure of both ground- and vegetation-dwelling arthropods. Landscape heterogeneity, alone and in interaction with farming systems, affected positively the diversity and abundance of most trophic groups for both ground- and vegetation-dwelling arthropods. Organic farming therefore affected the trophic composition of arthropod communities not only locally, but also at the landscape scale. Conclusions Our study highlights the strong positive effect of farming system and the landscape heterogeneity on arthropod communities and more importantly the interconnection between different spatial scales in this process. Taking these aspects into account is therefore crucial in understanding arthropod community dynamics in agroecosystems.}, language = {en} }