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Subterranean detritivores such as earthworms can increase soil nutrient availability through their burrowing and casting activities. A number of recent studies have explored whether these changes caused by earthworms may in turn affect plant performance and resistance to herbivores, but no formal synthesis of this literature has been conducted to date. We tested for the effects of earthworms on plant growth, resistance and chemical defences against insect herbivores by performing a meta‐analysis of the existing literature up to 2016. We also explored ecological factors that might explain among‐studies variation in the magnitude of the earthworm effects on plant growth and resistance. We found that earthworm presence increases plant growth (by 20%) and nitrogen content (by 11%). Overall, earthworms did not affect plant resistance against chewing herbivores (caterpillars, slugs and rootworms), and even led to a 22% decrease in plant resistance against phloem‐feeding herbivores (aphids). However, earthworm presence increased production of chemical defences by 31% when plants where attacked by cell‐feeders (thrips), and resulted in an 81% increase in resistance against thrips. The magnitude of earthworm effects was stronger when earthworm inoculations consisted of a mix of species and ecological types, and when densities of earthworms were high. These results suggest that earthworm presence is an important factor underlying natural variation in plant defences against herbivores, and call for a better integration of the soil fauna in the studies of plant‐herbivore interaction, both for applied and fundamental research. A plain language summary is available for this article. Plain Language Summary

Vincetoxicum rossicum is an invasive alien vine introduced from Europe in the late 1800s that is now an emerging pest in upstate New York and eastern Ontario. The plant can form dense, monotypic stands in woodlots and old fields, and may be displacing native vegetation. As a consequence, V. rossicum may be displacing arthropod fauna associated with native vegetation. In June and August 2002, we sampled V. rossicum and three other old field plants (Asclepias syriaca, Solidago altissima, and mixed graminoids) for arthropods using pitfall traps and by sampling individual plants. A total of 7868 arthropods were counted on plants and 18,195 individuals were trapped; these were sorted by feeding guild. Overall, stands of V. rossicum supported the lowest abundance of both stem- and ground-dwelling individuals, as well as the lowest number of arthropods in most phytophagous guilds. Some feeding guilds are entirely absent: V. rossicum stands are completely devoid of gall-makers and miners, and support few pollinators. This study suggests that arthropod diversity will decline if V. rossicum displaces native old-field plants.[PUBLICATION ABSTRACT]

Studies assessing the effect of urbanization on bird community structure largely carried out in developed countries and little is known about the developing region particularly in India. Bird diversity, richness, composition and guild structure was examined at urban, semi-urban, semi-rural and rural-natural sites in Aligarh, Uttar Pradesh. Each site was sampled using 90 fixed radius point counts between January and June 2016. Semi-urban site was more species rich (2.38 ± 0.06), diverse (0.80 ± .01) and even (0.90 ± .00) than other three urban-rural gradient sites. Density of bird peaked at urban site (43.09 ± 4.7). Numerically, urban site was dominated by omnivore species which was replaced by insectivorous species at semi-natural, semi-rural and rural-natural sites. The current information corroborates the earlier studies assessing impact of urbanization of birds and Conell’s intermediate disturbance hypothesis of higher richness and diversity at intermediate disturbance. 

Aim We examined whether the available surface area, temperature, or habitat complexity (foliage height diversity index) determine species richness of birds (and species richness of individual feeding guilds) along a complete forest elevational gradient. Further, we focused on the relationship between species richness of insectivorous birds and the availability of their food resources. Location Elevational gradient (200–3,700 m) of Mt Wilhelm (4,509 m a.s.l.), Central Range, Papua New Guinea. Taxon Birds. Methods We collected data on bird communities at eight sites (500 m elevational increment) during three surveys encompassing both dry and wet seasons over a 2‐year period. We used point counts, mist‐netting, and random walks throughout a standardized area. We tested three predictors of diversity and all of their combinations, in conjunction with sensitivity analyses for spatial effects. Habitat complexity (foliage height diversity index) and temperature were locally measured; surface area available within 200 m elevational intervals was obtained using GIS software. We further locally surveyed insect biomass and related it to species richness of insectivorous birds. Results Birds displayed a monotonic decline in species richness (from 113 to 35 bird species) with increasing elevation, and a nested pattern of species loss. The observed patterns were best explained by habitat complexity for the insectivores, frugivore‐insectivores, and total number of bird species. The available surface area was the best predictor for frugivorous birds. The mean temperature had a high correlation with species richness of all birds and gave the best fit of species richness for insectivore‐nectarivores and pure nectarivores. The biomass of insectivorous birds correlated with the biomass of arthropods. We ruled out the possibility that the elevational pattern observed in birds could be driven by a single phylogenetic radiation. Main conclusions We observed species richness patterns correlate well with habitat complexity and mean temperature, but mean temperature was not ranked as high as expected. Our results thus challenge the generally expected high importance of temperature as a regulator of water availability, production, and biochemical process that influence species richness, and underscore the importance of vegetation structure and the food resources as the driver of observed species richness.

The European Commission asked EFSA to revise the Guidance on the risk assessment for birds and mammals. That guidance described how to perform risk assessment for birds and mammals from plant protection products, containing pesticide active substances, in accordance with Regulation (EU) 1107/2009. The current guidance document is an update of EFSA's existing guidance document titled ‘Risk assessment for Birds and Mammals’ which was published in 2009. It outlines a tiered risk assessment scheme covering dietary exposure, exposure via secondary poisoning and exposure via intake of contaminated water.

There is abundant evidence that leaf mechanical traits deter feeding by insect herbivores, but little is known about which particular traits contribute to defence across feeding guilds. We investigated the contribution of multiple mechanical traits from shear, punch and tear tests to herbivore deterrence across feeding guilds. Visible damage from miners and external chewers was measured and sucker feeding density estimated in mature leaves of 20 species of forest shrubs and small trees. Cafeteria trials were undertaken using a generalist chewer (larvae of Epiphyas postvittana, Lepidoptera). Damage was compared with leaf mechanical traits and associated nutrient and chemical defence traits. Damage by external chewers in the field and by E. postvittana correlated negatively with mechanical traits. Hierarchical partitioning analysis indicated that the strongest independent contribution to chewing damage was by the material trait of specific work to shear, with 68 % of total variance explained by the combination of specific work to shear (alone explaining 54 %) and tannin activity in a regression model. Mining damage did not correlate with mechanical traits, probably because miners can avoid tissues that generate high strength and toughness in mature leaves. Mechanical traits correlated more strongly with chewing damage in the field than chemical defences (total phenolics and tannin activity) and nutrients (nitrogen and water), but nutrients correlated strongly with diet selection in the cafeteria trial. Surprisingly, sucker feeding density correlated positively with mechanical traits and negatively with nutrients. Mechanical traits of mature leaves influenced insect feeding guilds differentially, reflecting differences in life history and feeding modes. For external chewers, energy (work) to fracture in shearing tests, at both structural and material levels, was strongly predictive of damage. Knowing which leaf mechanical traits influence insect feeding, and in which guilds, is important to our wider understanding of plant-herbivore interactions.

Mycorrhizal status of the host plant is often ignored in studies on plant-herbivore interactions, but mycorrhizal colonization is known to induce many morphological, physiological, and biochemical changes in host plants, which in turn may alter plant quality as a host for insect herbivores. Both positive and negative effects of mycorrhizal colonization of the host plant on performance and density of insect herbivores have been reported in previous studies. We have conducted a meta-analysis of 34 published and unpublished studies on this topic in order to find out the sources of variation in mycorrhizae effects on insect herbivores. Effects of mycorrhizae on chewing insects depended upon the parameter measured and the degree of herbivore feeding specialization. Density and consumption of chewing insects were higher on mycorrhizal plants, but this did not lead to greater plant damage, presumably because herbivore survival tended to be lower on mycorrhizal plants. Mono- and oligophagous chewers benefited from mycorrhizal colonization of their host plants, whereas performance of polyphagous chewers was reduced on mycorrhizal plants. Among sucking insects, phloem feeders benefited from mycorrhizal infection, but performance of mesophyll feeders was lower on mycorrhizal plants. The type of mycorrhiza was not important for chewing insects, but performance of sucking insects was increased more by arbuscular mycorrhizal fungi (AM) than by ectomycorrhizae (ECM). Among AM inoculation studies, the most commonly used fungal species, Glomus intraradices, tended to have a negative effect on chewer performance, whereas all other fungal species tended to have a positive effect. There was no significant difference in results between studies using inoculation and fungicides, field and laboratory studies, and published and unpublished studies. Mycorrhizal status of the host plant thus influences insect herbivore performance, but the magnitude and direction of the effect depend upon the feeding mode and diet breadth of the insect and the identity of fungi.

Aim The aim was to quantify gradients in local richness levels, feeding strategies and body mass distributions in bats and relate them to environmental variation and habitat disturbance. Location The New World. Time period Present day. Major taxa studied Bats. Methods I assembled 152 local species inventories from the published literature, which include 245 species, along with body mass measurements and dietary categorizations. I quantified species richness using the Chao 1 extrapolator, obtained mean mass values for the inventories and computed proportions of species and of individuals belonging to different feeding guilds. I reduced the dimensonality of environmental variables using factor analysis and regressed richness values upon the factor scores. Results South of the Tropic of Cancer, bats exhibit sharp increases in local diversity, the abundance of frugivores and nectarivores, and mean body mass. These offsets are driven by increases in the richness and abundance of the leaf‐nosed bats (Phyllostomidae). Richness steeply declines near the Tropic of Capricorn, but the other variables do not trend strongly at this point. Most of the variance is explained by mean annual temperature, temperature seasonality and precipitation. There is no direct evidence that richness is lower in disturbed landscapes. Main conclusions The great radiation of phyllostomids in the Neotropics has created a uniquely rich biota. The reason that phyllostomids are now absent from the northern temperate zone might be that they are mostly frugivores or nectarivores. Therefore, they have prospered only in regions that provide fruit and nectar year‐round. Thus, biotic interactions might be the immediate cause of the latitudinal diversity gradient in New World bats. If so, then the biogeographical break is driven by environmental factors and is not a historical artefact. These results suggest that a more nuanced consideration of latitudinal gradients will prove to be helpful when it comes to studying many taxonomic groups.

An important group of protozooplankton, the ciliates, are a crucial component of aquatic food webs. They are the main grazers on bacteria and algae transferring carbon to higher levels of the food web (metazooplankton and fish fry). Changes in the quality and quantity of protozooplankton can modify the quality and quantity of metazooplankton, especially predatory copepods, causing changes in energy transfer and the matter cycle. Observable climate change is one of the most significant factors promoting the increase of cyanobacterial blooms. Therefore, the aim of this study was to find out how cyanobacterial blooms modify relationships between ciliates (prey) and copepods (predator), and to discover possible pathways of changes in freshwater food webs. We analysed the relationship between the biomass of predatory copepods and feeding guilds of ciliates (algivorous, bacterivorous, bacteri-algivorous). The relationship of predators biomass with algivorous and bacteri-algivorous ciliate biomasses, with a simultaneous lack of relationship with bacterivorous ciliate biomass, demonstrates that bacterial fixed carbon may be only partially contributing to the total energy passed through this link. Results demonstrated that the bloom enhanced the relationship between prey and predator. Larger and free-swimming ciliate species appear to play a greater role in energy transfer than smaller sedentary species.

Small public urban green spaces (SPUGS) are important for human life-quality and for maintenance of biodiversity within urban landscapes. However, little is known about how local characteristics and spatial location are related to biodiversity inhabiting SPUGS in tropical cities. In this study, we aimed at assess how noise, vegetation aspects (local characteristics), distance from a major habitat patch and from water (spatial location) are related to the bird community (species composition, species richness, total abundance and feeding guilds) inhabiting SPUGS in a medium-sized Neotropical city (Rio Claro, Brazil). We expected local characteristics to be the most important variables influencing the bird community. Bird observations were conducted in 28 SPUGS (< 1 ha) and we used generalized linear models and a multi-model inference to assess the relationships between SPUGS’ attributes and the bird community. Permutational multivariate analysis of variance was used to assess which SPUGS characteristics modulate species composition. We made 1,808 records of 75 bird species distributed in 26 families. Noise was negatively related to bird species richness, total abundance, and abundance of granivorous species. On the other hand, tree species richness presented positive relationships with bird species richness and total abundance. Noise and tree species richness also were responsible for modulating the composition of species inhabiting SPUGS. Therefore, we demonstrated that local characteristics modulate birds inhabiting SPUGS; while noise is a strong limiting factor for birds inhabiting these small green spaces, increasing tree species richness can enhance SPUGS’ ability in harboring a diverse bird community.Representation of the outcomes of our study: in Rio Claro (São Paulo, Brazil), small public urban green spaces (SPUGS) nearby quieter streets and with higher tree species richness harbor highly diverse bird communities. Noise was negatively related to bird species richness, total abundance and abundance of granivorous bird species, while tree species richness presented positive relationships with bird species richness and total abundance. This figure has been designed using resources from https://www.Freepik.com