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- Can School Children Support Ecological Research? Lessons from the Oak Bodyguard Citizen Science ProjectPublication . Castagneyrol, Bastien; Valdés-Correcher, Elena; Bourdin, Audrey; Barbaro, Luc; Bouriaud, Olivier; Branco, Manuela; Centenaro, Giada; Csóka, György; Duduman, Mihai-Leonard; Dulaurent, Anne-Maïmiti; Eötvös, Csaba B.; Faticov, Maria; Ferrante, Marco; Fürjes-Mikó, Ágnes; Galmán, Andrea; Gossner, Martin M.; Harvey, Deborah; Howe, Andy G.; Kaennel-Dobbertin, Michèle; Koricheva, Julia; Löveï, Gábor L.; Lupaștean, Daniela; Milanović, Slobodan; Mrazova, Anna; Opgennoorth, Lars; Pitkänen, Juha-Matti; Popović, Marija; Roslin, Tomas V.; Scherer-Lorenzen, Michael; Sam, Katerina; Tahadlová, Markéta; Thomas, Rebecca; Tack, Ayco J. M.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.
- Diversity of ground-active spiders in Negev desert habitats, IsraelPublication . Lubin, Yael; Ferrante, Marco; Musli, Iris; Lövei, Gábor L.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.
- Cold Storage Effects on Fitness of the Whitefly Parasitoids Encarsia sophia and Eretmocerus hayatiPublication . Kidane, Dawit; Ferrante, Marco; Man, Xiao-Ming; Liu, Wan-Xue; Wan, Fang-Hao; Yang, Nian-WanSuccessful biological control of the whitefly Bemisia tabaci involves the mass rearing of biocontrol agents in large numbers for field release. Cold storage of the biocontrol agents is often necessary to provide a sufficient number of biocontrol agents during an eventual pest outbreak. In this study, the fitness of two whitefly parasitoids Encarsia sophia Girault and Dodd (Hymenoptera: Aphelinidae) and Eretmocerus hayati Zolnerowich and Rose (Hymenoptera: Aphelinidae) was evaluated under fluctuating cold storage temperatures. The emergence rate of old pupae of either species was not affected when stored at 12, 10, 8 and 6 °C for 1 week. Cold storage had no effect on the longevity of the emerging adult En. sophia except young pupae stored at 4 °C, while Er. hayati was negatively affected after 2 weeks of storage time at all temperatures. Parasitism by adults emerging from older pupae stored at 12 °C for 1 week was equivalent to the control. Combined with the results for the emergence time, we suggest that the old pupal stage of En. sophia and Er. hayati could be stored at 12 and 10 °C, respectively (transferred every 22 h to 26 ± 1 °C for 2 h), for 1 week, with no or little adverse effect.
- Distribution of ecosystem services within oilseed rape fields : Effects of field defects on pest and weed seed predation ratesPublication . González, Ezequiel; Seidl, Miroslav; Kadlec, Tomáš; Ferrante, Marco; Knapp, MichalFrequent extreme weather events, which jeopardize agriculture by affecting crop health, characterize the ongoing climate change. Temporary patches where sown plants are poorly developed (hereafter “field defects”) are likely to increase with climate change and can be colonized by other plant species. Although perennial non-crop habitats can act as refuges for beneficial insects in agricultural landscapes and increase ecosystem services (ESs) in neighbouring arable fields, the relevance of field defects is unknown. Here, we quantified two ESs (pest and weed seed predation) in field defects within oilseed rape crops and related the ES levels with the activity-density of ground beetles and temperature. In 10 fields, we used artificial caterpillars made of plasticine and seed cards of two weed species (Taraxacum sp. and Stellaria sp.) to quantify the ESs in two sampling periods (spring and summer) and three habitat types: field defects, crops grown in standard conditions (field interiors) and crop-defect boundaries. Ground beetles were sampled using pitfall traps and classified into feeding guilds and body-size classes. Insects and mammals were the main pest predators, and predation increased in summer but did not differ among habitats. Seed predation rates for both species were significantly higher in summer. Predation upon Taraxacum seeds was higher in the field interiors, whereas the predation rate upon Stellaria seeds was significantly higher in the field interiors and defects compared to that in the crop-defect boundaries. The predation rate by insects increased with the activity-density of the medium- and large-sized carnivorous carabids, whereas the seed predation rate for both weed species was positively related to the activity-density of medium-sized herbivorous carabids. Finally, the mean and maximum temperatures were negatively linked to the predation rates on artificial caterpillars and seeds of Taraxacum, respectively. Our results suggest that these ephemeral habitats are not related to a strong decrease in ecosystem services; thus, field defects may not cause substantial changes in ES provisioning. We confirmed that ground beetles are important providers of both investigated ESs and showed that microclimatic conditions might play an important role in the regulation of ESs in agroecosystems.
- Seed Predation on Oil-Polluted and Unpolluted Vachellia (Acacia) Trees in a Hyper-Arid Desert EcosystemPublication . Ferrante, Marco; Möller, Daniella M.; Möller, Gabriella M.; Lubin, Yael; Segoli, MichalAcacia trees are keystone species in many arid environments, supporting high levels of plant and animal diversity. In Israel, the populations of Vachellia (formerly Acacia) tortilis (Forssk.) and V. raddiana (Savi) are declining at an alarming rate. Severe infestations by bruchid beetles (Coleoptera, Chrysomelidae) are among the major causes of seed mortality, but additional environmental stressors can reduce the defence level of the seeds, exacerbating their susceptibility to predators. In a hyper-arid desert ecosystem affected by two major oil spills (in 1975 and 2014), we quantified seed predation rates caused by insect granivores before and after the pods dropped to the ground. We recorded predation rates of up to 84% for both tree species, and higher predation rates at the ground level than in the canopy, suggesting that repeated infestations occur. These results reinforce the call to protect the populations of large ungulates such as gazelles, which kill the bruchids by feeding upon the pods, and promote seed germination and dispersion. We found no clear evidence of a negative effect of the oil spill on seed predation, indicating that oil pollution did not increase the vulnerability of the seeds to granivores even in trees affected by the recent oil spill.
- Diversity of Bird Communities in Tea (Camellia sinensis) Plantations in Fujian Province, South-Eastern ChinaPublication . Imboma, Titus S.; Ferrante, Marco; You, Min-sheng; You, Shijun; Lövei, Gábor L.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 (2018–2019) 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, 32–47 of those regularly visiting tea plantations. Species-accumulation curves indicated the near-completeness of the census. The Rényi 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.
- Search for top‐down and bottom‐up drivers of latitudinal trends in insect herbivory in oak trees in EuropePublication . Valdés‐Correcher, Elena; Moreira, Xoaquín; Augusto, Laurent; Barbaro, Luc; Bouget, Christophe; Bouriaud, Olivier; Branco, Manuela; Centenaro, Giada; Csóka, György; Damestoy, Thomas; Dobrosavljević, Jovan; Duduman, Mihai‐Leonard; Dulaurent, Anne‐Maïmiti; Eötvös, Csaba B.; Faticov, Maria; Ferrante, Marco; Fürjes‐Mikó, Ágnes; Galmán, Andrea; Gossner, Martin M.; Hampe, Arndt; Harvey, Deborah; Gordon Howe, Andrew; Kadiri, Yasmine; Kaennel‐Dobbertin, Michèle; Koricheva, Julia; Kozel, Alexander; Kozlov, Mikhail V.; Lövei, Gábor L.; Lupaștean, Daniela; Milanović, Slobodan; Mrazova, Anna; Opgennoorth, Lars; Pitkänen, Juha‐Matti; Popova, Anna; Popović, Marija; Prinzing, Andreas; Queloz, Valentin; Roslin, Tomas L.; Sallé, Aurélien; Sam, Katerina; Scherer‐Lorenzen, Michael; Schuldt, Andreas; Selikhovkin, Andrey; Suominen, Lassi; Tack, Ayco J. M.; Tahadlová, Markéta; Thomas, Rebecca; Castagneyrol, BastienAIM: 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.
- The Parasitoid Eretmocerus hayati Is Compatible with Barrier Cropping to Decrease Whitefly (Bemisia tabaci MED) Densities on Cotton in ChinaPublication . Zhang, Xiaoming; Ferrante, Marco; Wan, Fang-Hao; Yang, Nian-Wan; Lövei, Gábor L.The whitefly, Bemisia tabaci (Gennadius) cryptic species Mediterranean (MED), is a destructive insect pest worldwide. In order to contribute to controlling B. tabaci by non-chemical methods, we examined the possibility of using a combination of trap/barrier crops and a parasitoid natural enemy in cotton. We performed field experiments using cantaloupe (Cucumis melo) and sunflower (Helianthus annuus) as trap crops and maize (Zea mays) as a barrier crop combined with periodic releases of the parasitoid Eretmocerus hayati in Hebei Province, Northern China. All treatments significantly reduced immature whitefly densities. Parasitism rate was significantly higher in cotton plots intercropped with sunflower and with perimeter-planted cantaloupe. Adult whitefly density was negatively related to parasitoid abundance and was significantly lower in cotton plots intercropped with maize than in the control plots. Intercropping was more effective than perimeter-planting at reducing B. tabaci densities and increasing yield. Parasitoid dispersal was not hampered by barrier crops, indicating that the two methods of control are compatible. These results contribute to the development of integrated pest management methods against this important pest.
- A novel morphological phenotype does not ensure reduced biotic resistance on an oceanic islandPublication . Ferrante, Marco; Nunes, Rui; Lamelas-López, Lucas; Lövei, Gabor L.; Borges, Paulo A. V.Biotic resistance by the local community is a prominent theory seeking to explain invasion success or failure. Oceanic island communities might be prone to invasions because of their assumed low biotic resistance, due to low species richness and ecological naivety towards invaders. Biotic resistance, however, has rarely been quantified. We attempted such quantification on Terceira Island (Azores, Portugal) using the sentinel prey method. Vanessa virginiensis, a widely distributed Nearctic butterfly, has not been recorded on Terceira, and their caterpillars have characteristic green–black stripes that make it dissimilar to other Azorean caterpillars. We examined whether predation rate (PR) on plasticine caterpillars mimicking the unfamiliar V. virginiensis pattern were lower than on familiar green ones. We exposed a total of 4479 caterpillars in native forests and five non-native habitats, the agroecosystems orchards, vineyards, low and high elevation maize fields, and intensively managed pastures. Overall PR was higher on caterpillars with the unfamiliar than with the familiar pattern (6.4%d⁻¹ vs. 3.7%d⁻¹). Invertebrate PR was also significantly higher on the unfamiliar than on the familiar pattern in the native forest (5.9%d⁻¹ vs. 1.0%d⁻¹), as well as vertebrate PR in orchards (4.8%d⁻¹ vs. 2.3%d⁻¹) and low elevation maize fields (7.4%d⁻¹ vs. 2.2%d⁻¹). Our results suggest the existence of biotic resistance even on a species-poor, remote island, and that a novel morphological phenotype in itself does not guarantee reduced predation pressure.
- Oil Pollution Affects the Central Metabolism of Keystone Vachellia (Acacia) TreesPublication . Ferrante, Marco; Dangol, Anuma; Didi-Cohen, Shoshana; Winters, Gidon; Tzin, Vered; Segoli, MichalVachellia (formerly Acacia) trees are native to arid environments in Africa and the Arabian Peninsula, where they often support the local animal and plant communities acting as keystone species. The aim of this study was to examine whether oil pollution affected the central metabolism of the native keystone trees Vachellia tortilis (Forssk.) and V. raddiana (Savi), as either adults or seedlings. The study was conducted in the Evrona Nature Reserve, a desert ecosystem in southern Israel where two major oil spills occurred in 1975 and in 2014. Leaf samples were collected to analyze the central metabolite profiles from oil-polluted and unpolluted adult trees and from Vachellia seedlings growing in oil-polluted and unpolluted soils in an outdoor setup. We found that oil pollution had a stronger effect on one-year-old seedlings than on adult trees, reducing the levels of amino acids, sugars, and organic acids. While adult trees are mildly affected by oil pollution, the effects on young seedlings can cause a long-term reduction in the population of these keystone desert trees, ultimately threatening this entire ecosystem.
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