Journal of Economic Entomology
◐ Oxford University Press (OUP)
Preprints posted in the last 30 days, ranked by how well they match Journal of Economic Entomology's content profile, based on 12 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Bout, A.; Warot, S.; Cesari, L.; Hamidi, R.; Caravel, C.; Talamas, E.; Tortorici, F.; Ris, N.
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Stink bugs (Hemiptera Pentatomidae) are major agricultural pests worldwide, including both native and invasive species. In France, for instance, Halyomorpha halys has rapidly expanded its range, affecting key crops such as hazelnuts, apples, and vegetables. Meanwhile, several native, polyphagous species - Nezara viridula, Palomena prasina and, to a lesser extent, Graphosoma italicum - are re-emerging and impacting diverse crops because of changes in agricultural practices and climatic conditions. Egg parasitoids represent promising biological control agents for these pests, be it through conservation, augmentation or introduction biological control. However, their actual potential is not precisely documented due to a lack of ambitious surveys and possible taxonomic issues. This study aims to address this gap by compiling results obtained from various of egg parasitism surveys of Pentatomidae in France and implementing a large-scale DNA Barcoding approach (2000 individuals) for the emerged parasitoids. Our results indicate a high diversity of egg parasitoids, and detected some taxonomic issues and molecular inconsistencies that warrant further study. Among the three families of egg parasitoids recovered (Encyrtidae, Eupelmide, and Scelionidae), Scelionidae was the most abundant and diverse with nine species of Trissolcus (including the two adventive species, Tr. japonicus and Tr. mitsukurii) and four Telenomus species (including two unidentified to species). Scelionidae dominated the parasitoid assemblages associated with most of the Pentatomidae host species, except for H. halys for which the eupelmid Anastatus bifasciatus was the most common species.
Pandey, S.; Shilpi, S.; Roshanlal, V.; Meena, H. S.; Singh, C. P.; Shukla, J. N.
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Salivary secretions of herbivorous insects contain proteins that modulate plant defence and facilitate herbivory. Despite the broad host range of Spodoptera frugiperda, a major agricultural pest, its salivary molecular arsenal involved in interactions with different host plants remains poorly understood. In particular, the salivary proteins induced during feeding on different host plants and their potential interactions with plant immune components remain largely unexplored. To address this gap, we generated salivary gland transcriptomes from larvae reared on an artificial diet as well as larvae fed on tomato or chickpea plants. Comparative transcriptomic analysis identified salivary genes that were differentially expressed in response to plant feeding compared with the artificial diet. The encoded proteins were subsequently analysed using a secretory protein prediction pipeline to identify host-induced putatively secreted proteins with potential effector functions. Candidate salivary effectors were further investigated using large-scale in silico protein-protein interaction analyses with AlphaPulldown to predict their interactions with immune-pathway associated proteins of tomato and chickpea. This analysis identified multiple putative salivary effector candidates whose expression was induced by plants feeding, with distinct candidate repertoires associated with tomato and chickpea. Predicted interactions between these candidates and plant immune-associated proteins further identified potential host targets. Together, these findings suggest that S. frugiperda may adjust its salivary molecular repertoire in response to the host plant and provide a transcriptome-wide framework for validating effector-target interactions and elucidating the molecular mechanisms underlying S. frugiperda-plant interactions.
Coroller-Chouraki, S.; Savage, J.; Pelletier, F.; Garant, D.; Belisle, M.
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Feathers incorporated into bird nests are thought to provide multiple benefits, including thermal insulation and protection against nest-dwelling ectoparasites. For instance, in Swallows, it has been suggested that feathers influence infestations by Protocalliphora blow flies either by acting as a physical barrier between larvae and nestlings or through chemical compounds associated with preen oil. However, empirical evidence for an antiparasitic effect of feathers remains equivocal. Using 1,100 naturally infested Tree Swallow (Tachycineta bicolor) nests collected from a nest-box study system monitored in southern Quebec, Canada, between 2004 and 2018, we tested whether nest mass and feather abundance influenced hematophagous ectoparasites (Protocalliphora spp.) loads. We further assessed whether feather abundance directly affected body size using measurements of 1,513 P. sialia puparia, and emergence success using data from 961 Protocalliphora spp. puparia. Nest mass was positively associated with feather abundance, and both variables showed very weak positive relationships with parasite abundance. Feather abundance was unrelated to puparium size nor parasite emergence success. Our results provide no support for an anti-parasitic effect of feather lining within Tree Swallow nests. Using one of the largest datasets assembled to date on feather-lined nests and avian blow flies, we found no evidence that feather abundance impairs Protocalliphora density, development or emergence success. However, our findings do not preclude potential effects of feathers on other ectoparasites or microorganisms with different life histories. Future studies simultaneously monitoring multiple parasite taxa (such as fleas, mites, or bacteria) may therefore be needed to fully evaluate the ecological consequences of feather lining within avian nests.
Coroller-Chouraki, S.; Savage, J.; Belisle, M.
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Morphological variation in insects can indicate responses to habitat change and land use intensification, with potential consequences for trophic interactions. In insect host-parasitoid systems, host body is often a key determinant of offspring development and emergence success, as well as parasitoid host-selection behavior. Yet, most studies in agricultural landscapes have focused on size variation in crop-associated insects (i.e.: pests, pollinators and enemies), leaving those relying on non-crop resources largely unexplored. Here, we investigated how agroenvironmental contexts and trophic resource availability influence puparial size in Protocalliphora sialia (Diptera: Calliphoridae), an obligate hematophagous ectoparasite of Tree Swallow (Tachycineta bicolor) nestlings. We further tested whether puparial size affects emergence probability and risk of parasitoidism by Nasonia spp. (Hymenoptera: Pteromalidae) jewel wasps. Using 1,513 P. sialia puparia from 88 nests within a nest-box monitoring system spanning a 10,200-km^2 east-west intensification gradient in southern Quebec, Canada, we evaluated how agrointensive contexts, avian host availability, and ectoparasite densities influence puparial size, parasitoidism risk, and emergence success. The agricultural context appears to shape puparial size through survival biases and/or altered growth rates. In agroextensive contexts (i.e.: pastures, forages with high tree cover), where Protocalliphora are more numerous, P. sialia puparia were smaller and exhibited greater size variation. Conversely, in agrointensive environments (maize and soybeans monocultures with higher doses of pesticides), where Protocalliphora are fewer, small individuals were underrepresented, suggesting a selective mortality in P. sialia population. However, puparial size explained less than 10% of the variation in emergence or parasitism, likely reflecting consistently high parasitic pressure from Nasonia wasps, which infested 50-90% of puparia, depending on site and year. Our findings highlight the importance of selective mortality in structuring trait distributions and modulating multi-trophic interactions in human-modified landscapes.
Blyton, M. D. J.; Dierens, L.; Lacour, M.; Hugenholtz, P.
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As a specialist herbivore, koalas rely on their gut microbiomes to help digest their toxic and fibrous diet of Eucalyptus leaves. Without these critical microbes, koalas may not be able to obtain the nutrients and energy they need to survive. As such, a large proportion of koalas that undergo rehabilitation for chlamydiosis develop gut dysbiosis from the antibiotic treatment and are either euthanized or die. Here we aimed to modify previously developed fresh faecal inoculation capsules for an extended shelf-life such that they could be applied in a clinical setting to prevent or treat gut dysbiosis. Using 16S rRNA gene amplicon sequencing we demonstrated that air-drying faecal material leads to an overgrowth of facultative anaerobes, whereas lyophilised material retains a similar microbial composition to fresh material. Initial survival of koala faecal microbes as assessed by live/dead staining combined with microscopy was high after lyophilisation regardless of which excipient was used, except for 20% glycerol that resulted in ~15% lower survival than other treatments. Lyophilised fine particles extracted from koala faeces and packaged into acid-resistant capsules maintained their original microbial composition and had high microbial survival over a year, regardless of the excipient used. Dry-fill, single-layer capsules maintained integrity after 10 hrs in synthetic koala stomach acid. These capsules may be useful in adapting the gut microbiomes of koalas to novel diets e.g. during translocations. However, attempts to apply the capsules in the clinical setting were unsuccessful due to unanticipated difficulties in administrating the capsules to sick koalas.
Boeraeve, F.; Noel, G.; Bortels, J.; Francis, F.; Desgain, M.; Sirami, C.; Vialatte, A.; Caro, G.; Dufrene, M.
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The potential of alternative agricultural systems, such as organic or conservation agriculture, for biodiversity restoration has been widely investigated. However, variability of practices within each of these two categories of agricultural system has rarely been accounted for. Furthermore, these systems have most often been studied separately, isolating either organic or conservation agriculture (itself often reduced to a soil tillage reduction), and rarely analyzing these systems side by side. This study attempts to disentangle these multiple interrelationships by sampling carabid beetles in a network of 48 commercial Belgian farms including organic agriculture (OA), conservation agriculture (CA), farms combining the two approaches (OCA) and farms applying conventional practices (CVA). In each farm, we sampled carabids using pitfall and emergence traps in one winter cereal field and collected a detailed description of crop management practices. We found that community composition was primarily structured by seasonality early in the season (March, April) followed by convergence (May, June) driven by the aggregation of the most dominant species. Based on agroecosystem classification, organic certification (i.e., the absence of synthetic pesticide use) exerted a twofold stronger effect than application of conservation agriculture principles (i.e., reduced or no soil tillage) on carabid beetle community composition. Notably, OCA supported carabid assemblages that were structurally distinct from those of CA and CVA. Furthermore, carabid communities associated with OA differed significantly in composition from those of CVA. Observed and estimated species richness were also significantly higher in OCA than in CA and CVA, while OA differed from CVA only for observed richness. Beyond differences among agricultural systems, community responses were associated with specific management practices, which explained nearly a quarter of the compositional variation with significant influence of the duration since organic conversion and the frequency of synthetic pesticide application. Carabid abundances were negatively affected by synthetic pesticides and moldboard ploughing, whereas richness was more strongly related to the time since conversion to OA, cover crops, and organic amendments. Overall, these results position synthetic inputs and time since conversion as the main filters over carabid communities. Our study highlights the importance of jointly considering system level analyses and detailed management practices to better understand the complex relationships between agricultural practices and carabid communities.
Vandenberghe, E.; Vereecken, S.; Reuss, F.; Brusius, I.; Janssens, C.; Magdeburg, A.; Groneberg, D. A.; Muller, R.; Kramer, I. M.
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In Germany, insecticide use is recommended during mosquito-borne disease outbreaks, yet nationwide data on insecticide resistance in key vector species are scarce. This is particularly relevant for Culex pipiens s.l., a vector of West Nile virus. Here, we provide the first broad-scale assessment of molecular insecticide resistance (kdr and ace-1 mutations) in Cx. pipiens f. pipiens across Germany. We associated insecticide resistances with environmental conditions, potential links with mitochondrial variation of the cytochrome c oxidase I (COI) gene as well as phenotypic resistance (CDC bottle assay with permethrin) of the Frankfurt population with elevated kdr frequencies. Kdr resistance alleles were detected in German Cx. pipiens f. pipiens reaching frequencies of up to 50% in the metropolitan areas of Berlin and Frankfurt am Main. Annual precipitation was negatively associated with kdr allele frequency. Interestingly, ace-1 resistance mutations were only present in the metropolitan area of Frankfurt am Main and in Muggensturm (Rhine valley, southwestern Germany). COI haplotype analyses revealed low genetic variability within German Cx. pipiens f. pipiens populations with no association to the insecticide resistance genotype. Phenotypic assays of the Frankfurt population showed early signs of permethrin resistance, but unmatched genotypic and phenotypic resistance state. This study provides the first broad-scale assessment of molecular insecticide resistance in Cx. pipiens f. pipiens across Germany, establishing a baseline for resistance surveillance and vector control. Further research is needed to identify factors shaping phenotypic resistance, as molecular markers alone may not reliably predict resistance. Since sampling was restricted to urban green spaces, broader sampling across environmental gradients is needed to identify additional environmental effectors.
Iberl, K.; Kirschner, P.; Koc, A.; Hasakova, T.; Wellstein, C.; Stenc, J.
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Understanding floral visitor dynamics along elevational gradients is essential for assessing potential implications for pollen limitation and population genetic processes in fragmented populations of cliff-dwelling alpine endemics. Physoplexis comosa (Campanulaceae) is a chasmophytic paleoendemic restricted to vertical rock faces on dolomitic and limestone bedrock from 200 to 2,800 m a.s.l. The species exhibits a specific floral morphology with fused corolla apices, basal openings for nectar access, and secondary pollen presentation, yet its functional floral visitor assemblage has remained poorly characterized across the species' elevational range. In this pilot study, we tested a two-tier camera-monitoring setup combining action cameras for diurnal monitoring with Raspberry Pi-based systems equipped with IR illumination for combined diurnal and nocturnal recording. We conducted monitoring across five elevational sites (1,480 to 2,400 m a.s.l.) in the Eastern Alps. Recorded video material was downsampled and annotated using the Addax platform alongside manual cross-validation to record physical contact events. Preliminary results confirm the technical feasibility of continuous monitoring in steep terrain and suggest possible elevational variation in diurnal visitors, alongside nocturnal activity by Geometridae moths. Camera-based observations provided higher functional resolution and revealed a different visitor assemblage than previous eDNA metabarcoding trials. This proof-of-concept establishes a methodological foundation for forthcoming multi-day monitoring campaigns and complements ongoing studies of the mating system and population-genetic analyses.
Maleki, K.; Connolly, L.; Lorenz, N.; Amphonechit, T.; Lindsey, A.; Perales, H.; Bernau, V.; Dick, R.; Mercer, K.
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Synthetic nitrogen fertilizers enhance maize (Zea mays ssp. mays) productivity but impose substantial environmental and economic costs. Some Mexican maize landraces support biological nitrogen fixation (BNF) in aerial root mucilage, raising the question of how much variation exists in this trait and how domestication, geographic spread, and improvement have shaped BNF-related traits across Zea in the Americas. We evaluated aerial root traits and BNF capacity across the maize domestication continuum using 60 Zea accessions grown in field experiments over two years under low-N conditions. Some accessions of wild Zea, landraces from Mexico and South America, and improved varieties had elevated nitrogen derived from the atmosphere (%Ndfa), ranging from 20 to 40%; some of these also had greater %Ndfa than typical improved varieties. Spread and improvement appear to have significantly reduced the number of aerial root-bearing nodes, with wild Zea and Mexican landraces consistently producing more. Nevertheless, the proportion of nitrogen derived from the atmosphere (%Ndfa) does not vary systematically across the domestication continuum. Thus, crop evolution shaped aerial root phenotypes more than associative BNF capacity. The persistence of substantial within-group variation indicates that the genetic potential for enhanced BNF remains within the Zea gene pool, providing opportunities to encourage and improve nitrogen use efficiency in maize cropping systems.
Coroller-Chouraki, S.; Savage, J.; Belisle, M.
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Agricultural intensification is a major cause of population declines in farmland birds and insects worldwide. While these declines are expected to disrupt trophic interactions through density-dependent cascading effects, examples outside of crop pest control or involving more than two trophic levels remain poorly documented. Here we quantify such cascading effects across three trophic levels involving a declining aerial insectivore, the Tree Swallow (Tachycineta bicolor), which breeding success decreases with agricultural intensity, Protocalliphora bird blowflies (Diptera: Calliphoridae) that parasitize its nestlings, and Nasonia parasitoid jewel wasps (Hymenoptera: Pteromalidae) that feed upon blowfly pupae within swallow nests. Agriculture intensity may affect each of these actors either directly via, for instance, toxicological effects from pesticide use, or indirectly through density-dependent trophic interactions, which can exacerbate or mitigate one another. Using Bayesian models within a causal inference framework, we quantified how nestling host density, meteorological conditions, and agricultural landscape context affect Nasonia parasitoid infestation of Protocalliphora pupae, and estimated Protocalliphora emergence success. Analyses were based on 3,340 Protocalliphora puparia collected from 248 Tree Swallow nests over a 16-year period (2004-2019) across a 10,200-km2 agricultural intensity gradient in Southern Quebec, Canada. Model predictions indicated that Protocalliphora emergence probability increased steeply with nestling host availability (i.e., nestling-days). Whereas Nasonia parasitoid infestation occurrence at the nest level increased with Protocalliphora host availability, the proportion of infested Protocalliphora pupae within nest decreased and led to a dilution effect at the individual level. Although Protocalliphora abundance within nests decreased with agricultural intensity, their emergence probability peaked in agrointensive landscapes. This increase was associated with reduced Nasonia infestation rates, suggesting that agricultural intensity indirectly mitigated parasitoid pressure on Protocalliphora host populations. Our results highlight how agricultural intensification can shape multitrophic interactions and life-history traits (emergence success and infestation rates) by simultaneously reducing host availability and weakening top-down control by parasitoids.
Scheepens, D. R.; Newbold, T.; Freeman, R.
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Anticipating and managing the impact of herbivorous pests requires evidence-based knowledge about the interactions between pests and their natural enemies. Knowledge of species' ecologies and biological interactions are typically disseminated in unstructured text across hundreds of thousands of scientific articles spanning a rapidly growing scientific literature, but manually screening this literature is time-consuming and impractical at scale. Taxonomic and geographic coverage thus remains sparse, and structured data on interactions between individual species are lacking, particularly for invertebrates. Large language models (LLMs) have recently emerged as a novel and powerful text-mining tool for knowledge extraction and evidence synthesis in a wide range of scientific disciplines, including ecology and conservation. In this study, we use an open-weight, pre-trained LLM to analyse abstracts of a corpus of published material on biological pest control to obtain a global Database of Pest Herbivores and their Natural Enemies (DAPHNE). This method resulted in the extraction of 175,404 species interactions from 112,830 published pest control studies, containing16,755 unique animal taxa resolved at the species level. Interactions include herbivory (granivory, frugivory and gall-formation), predation, parasitism and hyperparasitism, and comprise a range of additional information, such as species' taxonomy, pest status, pest importance, natural enemy importance, provision of biocontrol, associated plants and industries, invasiveness and the vectoring of pathogens and diseases. Validation of the results shows that most data columns were extracted with high recall and precision (>90%) and comparison of DAPHNE with other sources shows a high degree of agreement, but also highlights that the dataset contains information that may have been missed by other sources. In addition to the identification of important crop pests and their natural enemies, DAPHNE may be used for a variety of use-cases, including the identification of invasive species and pathogen vectors, trophic network analysis and literature search and discovery.
Biswas, S.; Bhattacharyya, S.
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Fallen fleshy fruits are temporary resource patches that can support diverse but transient invertebrate assemblages, yet their successional dynamics remain poorly documented in tropical landscapes modified by human activity. We examined heterotrophic succession on fallen ripe guava fruits, Psidium guajava, in a tropical grove in Barasat, West Bengal, India. Eight fruits were placed in exposed and shaded microhabitats and followed from fresh to degraded stages over 22 days. Invertebrates were recorded using repeated scan sampling, and daily observations for each fruit were analysed for taxon richness, Shannon diversity, total peak relative abundance, community composition and indicator taxa associated with decomposition stages. Across 141 daily fruit observations, we recorded 44 invertebrate taxa. Taxon richness, Shannon diversity and total peak relative abundance were highest during fresh and pre rotten stages and declined sharply during post rotten and degraded stages. Decomposition stage was the strongest predictor of alpha diversity, resource use intensity and community composition, whereas differences between exposed and shaded microhabitats were weaker. Indicator taxa showed clear successional replacement: fresh fruits were associated with drosophilid and tephritid flies; fresh and pre rotten fruits with nitidulid beetles and ants; and later stages with collembolans, staphylinids, blattodeans and other taxa associated with detrital stages. Ants, especially Pheidole sp., were conspicuous resource users and showed guarding, hoarding, predation and pulp or seed removal behaviour, although their effects on other taxa remain observational. These results show that fallen guava fruits function as ephemeral heterotrophic resource patches, supporting rapid invertebrate turnover at fine temporal scales in a tropical grove.
Eke, M.; Tougeron, K.; Martin, M.; Ambroise, J.; Bearzatto, B.; Gala, J.-L.; Ngamo Tinkeu, L.; Hance, T.; Renoz, F.
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Due to their highly polyphagous capacities, black soldier fly (Hermetia illucens) larvae (BSFL) are increasingly valued for their ability to convert organic waste into valuable biomass that can be used for a variety of purposes. These remarkable digestive capabilities are highly dependent on an extremely plastic gut microbiota. However, the distribution and functioning of bacterial communities in the various gut compartments - particularly in the hindgut - remain little understood. In this study, we used a metabarcoding approach based on 16S gene sequencing to investigate the effect of three carbohydrate-rich diets with distinct molecular compositions on the functional diversity of the BSFL gut microbiota. Our results showed that the midgut harbors a highly substrate-sensitive microbiota, with a high abundance of Actinomyces spp., regardless of the substrate. A bacterial diversity oriented toward fatty acid biosynthesis pathways is promoted by starch-rich environment, whereas a lignocellulosic substrate fosters a midgut microbiota dominated by Paenibacillus spp. In contrast, the hindgut exhibits a distinctly stable and homogeneous bacterial composition dominated by Dysgonomonas spp. Overall, our results provide clear evidence of a two-compartment microbial system, in which the midgut primarily serves as a substrate-adaptive primary degradation chamber, while the hindgut functions as a stable terminal compartment for the final processing of residual substrates and the recycling of nutrients. These findings contribute to our understanding of the functional diversity of the bacterial microbiota along the BSFL digestive tract, which is a key factor in explaining this insect's remarkable polyphagous behavior and optimizing its use for industrial purposes.
Mupepele, A.-C.; Klein, A.-M.; Fornoff, F.
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Ground-nesting wild bees require suitable soil conditions for their below-ground development and overwintering life stages. Understanding how soil translocation and disturbance affect individuals and the following generations of bees is important for identifying conservation measures for ground-nesting wild bees. We investigated the effects of soil translocation and disturbance on the ground-nesting solitary spring mining bee Colletes cunicularius. In a replicated controlled design, we compared the effects of soil translocation with different degrees of disturbance on the number of surviving bees and the emergence time. We found that soil translocation and disturbance reduced bee survival but did not result in complete mortality, with some individuals surviving even under severe soil disturbance. There was no evidence that soil disturbance affected the timing of spring emergence, suggesting that disturbance is unlikely to alter the timing of nest construction and, consequently, the production of the next generation. Our results indicate that translocating soil containing overwintering bees could be a promising conservation measure to compensate for habitat loss caused by land conversion.
Bakhoum, M. T.; Fall, A. G.; Segard, A.; Seck, M. T.; Thiall, A. S.; Gimonneau, G.; Ravel, S.; DE MEEUS, T.
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In sub-Saharan Africa, human and animal health is threatened by African trypanosomoses. These diseases are caused by trypanosomes that are transmitted primarily by tsetse flies. Vector control remains one of the most effective strategies for reducing disease transmission, but requires a minimum level of knowledge of the population biology, ecology and dispersal patterns of the targeted vectors. In this respect, population genetic approaches using appropriate polymorphic genetic markers can provide valuable tools to inform and optimize control strategies. Senegal is currently engaged in a national tsetse control programme and has been identified as a study country within a European Union-funded research initiative, COMBAT (controlling and progressively minimizing the burden of animal trypanosomosis). Baseline entomological studies are currently underway in the Sine Saloum (Southern Senegal). This preliminary study aimed to characterize the population genetic structure and connectivity of tsetse fly species present in Southern Senegal, Glossina palpalis gambiensis and G. morsitans submorsitans, in order to assess their population sizes (geographically and demographically), population densities and dispersal capacities. The two species exhibited markedly contrasting population structures. The first, G. p. gambiensis, displayed an isolation by distance with rather dense subpopulations exchanging immigrants at short distances (1.6 km/generation) and continuously from Sine-Saloum to Casamance, in line with the apparent continuity of the mangrove network found along this coast. In contrast, G. m. submorsitans presented a relatively dense population over a 75 km wide area, fragmented into sparsely distributed, very dense and interconnected pockets. These findings indicate that G. p. gambiensis likely constitutes a large metapopulation comprising 3266 effective individuals on average (and up to 7765), whereas G. m. submorsitans appeared as a single and large population, scattered in small pockets that could be readily replenished by immigrants from distant areas in case of control. These results suggest that elimination is not a realistic option for any of these two populations. Alternatively, localized integrated pest management is likely to be the most effective approach for controlling the negative effects of these biting flies on domestic animals, by reducing trypanosome transmission. However, further entomological investigations and the use of more informative genetic markers are needed to obtain a more precise understanding of the epidemiological processes involved.
Pascual, K.; Bateson, M.
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Reliable morphological criteria for sexing birds without the need for invasive procedures are scientifically and ethically valuable. Smith et al (2005) reported that iris colour assigns the genetic sex of Starlings Sturnus vulgaris with 98% accuracy, and bill base colour with 100% accuracy when birds are in breeding condition, but these figures have not been tested independently. We applied their criteria to 31 captive Starlings in breeding condition, using three observers blind to genetic sex, two of them new to Starling sexing. Bill base colour correctly predicted genetic sex for all 29 birds scored, with complete observer agreement. Mean iris score was correct for 27 of 31 (87.1%), fewer than the 94 of 96 reported by Smith et al (2005) for birds in breeding condition (Fisher exact test, P = 0.031), although with so few errors in either study this comparison is imprecise. Observer agreement was high, so these errors reflect iris colouration conflicting with genetic sex rather than inconsistent scoring; bill base colour was correct for all four misassigned birds. Body mass and tarsus length classified 77% and 58% of birds correctly, their published thresholds missing in opposite directions. We conclude that bill base colour should be the primary criterion for sexing Starlings in breeding condition; the accuracy of iris colour should not be assumed to be 98%.
Mattila, T.; Niemi, J.; Kajasilta, H.; Myllyviita, T.; Vippola, T.; Hockerstedt, L.; Pihlainen, S.; Ekroos, J.
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Soil degradation is a widespread challenge that requires a broad response at the individual farm level. To ensure effectivity, the practices should be tailored to the farm context: land manager objectives and farm specific challenges. These have however been difficult to quantify. Here we demonstrate that a workable farm context can be created based on a value survey, open satellite and soil data, and published models for vegetation gross primary productivity and soil erosion. Based on the findings, despite individual differences, farmers value profitability and operational efficiency, but also biodiversity and soil health. At least the regenerative farmers surveyed also value working for the greater good more than maintaining tradition or power. In spite of wide differences in farm production orientation, we also found that each farm also had a broad variation in individual fields GPP. Most fields have a stable GPP level, which is either high or low, and that there is a 2-3-fold difference between the weakest and best producing fields indicating the potential for improving GPP by improving the growing conditions on currently weak fields. In addition, soil loss was found to be highly concentrated in critical source areas, where 10% of the field area contributed to 50% of the soil loss. Overall, open data can be linked to modelling workflows to rapidly produce a decision-making context for farmers. This facilitates benchmarking and co-learning as well as enables land managers and advisors to identify the farm context for planning effective responses to soil degradation.
Daecher, F.; Venkatesh, S.; Ayan, A.; Weerathunga, U. S.; Pushpakumara, T. V.; Abeywardana, V. P. M. K.; Thaufeek, U. L.; de Silva, S.
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Trail cameras have become ubiquitous tools for ecological data collection over recent decades. Despite progress in the development of automated algorithms and artificial intelligence for image classification, our ability to process large volumes of data remain limited by the need for trained human observers to make refined judgements. We provide guidance on placement of trail cameras for observing Asian elephants (Elephas maximus) and outline a protocol for training and testing naive human observers in performing image classifications (age/sex class and group composition) that cannot yet be automated. This process can be used to develop a high-throughput workflow capable of extracting useful data from large volumes of images. Our training material consisted of 14,007 images collected from 6 trail cameras around Udawalawe National Park in Sri Lanka from 2017-2019. In the first stage, expert observers (n=3) trained a group of inexperienced participants (n=4), who engaged in an iterative process to develop a protocol document. The document was then tested on a second set of subjects (n=6) each of whom classified 350 test images in four separate sequential batches using quantitative measures of precision and accuracy. The test set was sampled from 54,435 images from an additional 25 cameras. When compared to expert observers, they achieved a fair level of precision (Fleiss' kappa = 0.247) and 82.6% accuracy. Our approach can usefully be extended to other species and contexts.
Valencia-Esquivel, I.; Inchaurregui, I.; Martinez, A.; Zepeda, D.; Arce, E.; Osorio-Beristain, M.
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Diurnal ectotherms in hot and dry ecosystems face an acquisition trade-off between maximizing collective energy intake and minimizing individual exposure time. We employed optimal foraging and thermoregulation models to examine the surface foraging and thermoregulatory strategies of Pogonomyrmex barbatus foragers in response to habitat warming in a tropical deciduous forest. Foraging activity was evaluated using field-based thermal performance curves (fTPCs) for individual foraging speed and collective foraging success. Thermoregulation was assessed through indices of thermal unsuitability, as well as thermoregulatory effectiveness and exploitation. Our results show that afternoon conditions were significantly hotter and drier than those in the morning. Furthermore, the decoupling of fTPCs was dynamic; while the optimal temperature (Topt) for individual foraging speed remained stable at 44 degrees C, the Topt for collective foraging success shifted from 35 degrees C in the morning to 41 degrees C in the afternoon. This shift in foraging strategy, driven by stressful afternoon conditions, was reflected in a transition of the thermoregulatory strategy. Specifically, the probability of foraging activity decreased as thermal unsuitability increased, with a lower baseline in the afternoon. The thermoregulatory exploitation dropped from 94% in the morning to 63% in the afternoon. Based on thermoregulatory effectiveness, foragers transitioned from an active thermoregulatory strategy in the morning to a thermoconformist strategy in the afternoon while foraging on the surface. So, the observed colonies optimized the balance between individual foraging speed and collective foraging success through a thermoregulatory strategy that was primarily spatial in the morning and strictly temporal in the afternoon. A comparison with historical data from the same site reveals a 40% contraction in the total daily foraging window since 2013.
Malcherczyk-Bies, N.; Sierka, E.
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Extensive green roofs are an important component of urban green infrastructure. However, harsh rooftop conditions, including shallow substrates, high temperatures and limited water availability, considerably restrict plant selection. Although extensive green roofs are traditionally dominated by succulent species, increasing attention has been directed towards annual plants because of their rapid establishment, developmental plasticity and potential contribution to vegetation diversity. This review aimed to identify annual plant species introduced on extensive green roofs and to characterize the functional traits most frequently associated with their establishment under rooftop conditions. In addition, the review examined the geographical distribution and methodological characteristics of existing studies and identified species with potential for application under temperate climatic conditions. A total of 22 studies published between 2015 and 2025 were analyzed, comprising 100 annual species representing 29 plant families. The reviewed studies showed a clear geographical bias towards Mediterranean and arid regions, whereas temperate climates were considerably underrepresented. Among species occurring in Central Europe, ruderal life strategies, drought avoidance, efficient dispersal mechanisms, low plant height and prolonged flowering were the most frequently observed functional characteristics, while seed mass and specific leaf area (SLA) exhibited substantial interspecific variation. These findings suggest that functional traits, rather than taxonomic affiliation alone, provide a useful framework for selecting annual species for extensive green roofs. The review also highlights the need for long-term studies conducted under temperate climatic conditions to improve evidence-based plant selection and support the development of resilient and multifunctional green roof vegetation.