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BACKGROUND: By modelling species–environment relationships of pest species, it is possible to understand potential limits to their distributions when they invade new regions, and their likely continued spread. The European earwig, Forficula auricularia, is a non‐native invasive species in Australia that has been in the country for over 170 years. However, in the last few decades it has invaded new areas. Unlike in other countries, F. auricularia is a pest species of grain production in Australia. In this study we detail the Australian distribution of this species, adding new samples focused around grain‐growing regions. Using this information, we build global species distribution models for F. auricularia to better understand species–environment relationships. RESULTS: Our models indicate that the distribution of F. auricularia is strongly associated with temperate through to semi‐arid environments, a high winter rainfall and pronounced temperature seasonality. We identified regions that hold suitable, but as yet vacant, niche space for Australian populations, suggesting further potential for range expansion. Beyond climate, an index describing human influence on the landscape was important to understand the distribution limits of this pest. We identified regions where there was suitable climate space, but which F. auricularia has not occupied, probably due to low levels of human impact. CONCLUSION: Modelling the global distribution of a non‐native pest species aided understanding of the regional distribution limits within Australia and highlighted the usefulness of human impact measures for modelling globally invasive insect species. © 2018 Society of Chemical Industry The European earwig, Forcifula auricularia L., is a pest species of Australian grains. Here we examine relationships of F. auricularia to climate‐ and human‐impacted environments to understand distribution limits. [ABSTRACT FROM AUTHOR]

Context: Farming practices influence the degree of contrast between adjoining habitats, with consequences for biodiversity and species movement. Little is known, however, on insect community responses to different kinds of edges over time, and the extent of cross-habitat movement in agricultural landscapes.Objective: To determine temporal changes in beetle responses to different farmland-woodland edges, and document cross-habitat movement.Methods: We examined species richness, abundance, and movement across edges between remnant woodlands and four farmland uses (plantings, fallow, annual crops, woody debris applied over crops post-harvest) in southeastern Australia. We used directional pitfall traps to infer movement, and sampled at edges, and 20 and 200 m on both sides of edges, during spring and summer.Results: Detritivore and predator abundance varied between seasons across the edge between woodlands and all farmlands, but seasonal differences were weaker for fallow-woodland and woody debris-woodland edges. Detritivores moved from farmlands towards woodlands, but not across fallow-woodlands and woody debris-woodlands edges during summer. During summer, predators showed short-range movement towards edges from all farmlands except plantings, and towards woody debris from woodlands. Edges showed temporally stable predator richness and higher herbivore richness than adjoining habitats.Conclusions: Farmland use and season interactively affect beetle abundance across farmland-woodland edges. Woody debris can reduce seasonal fluctuations in beetle edge responses and increase permeability for cross-habitat movement, while plantings provide habitat during summer. Edges provide important resources for beetles in adjoining habitats, however, seasonal movement of predators specifically into edges may affect prey assemblages—a link requiring further study. [ABSTRACT FROM AUTHOR]

BACKGROUND This study examines whether leaf spectra can be used to measure damage to cassava plants from whitefly ( Bemisia tabaci), and the potential to translate measurements from leaf to landscape scale in eastern Africa. Symptoms of the cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) viruses, and sooty mould (SM) blackening of lower leaves from whiteflies feeding on the upper leaves, were measured at the leaf scale with a high-resolution spectroradiometer and a single photon avalanche diode (SPAD) meter, which retrieves relative chlorophyll concentration. Spectral measurements were compared to the five-level visual scores used to assess the severity of each of the three damaging agents in the field, and also to leaf chemistry data. RESULTS Leaves exhibiting severe CBSD and CMD were spectrally indistinguishable from leaves without any symptoms. Severe SM was spectrally distinctive but is likely to be difficult to map because of its occurrence in the lower crown. SPAD measurements were highly correlated with most foliar chemistry measurements and field scores of disease severity. Regression models between simulated Sentinel 2 bands, field scores and SPAD measurements were strongest using wavelengths with high importance weightings in random forest models. CONCLUSION SPAD measurements are highly correlated to many foliar chemistry parameters, and should be considered for use in mapping disease severity over larger areas. Remaining challenges for mapping relate to the subtle expression of symptoms, the spatial distribution of disease severity within fields, and the small size and complex structure of the cassava fields themselves. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

There is an urgent need to identify ways of managing agricultural landscapes for biodiversity conservation without reducing food production. Farming practices that consider spatio-temporal heterogeneity of farm fields may be a feasible alternative to large-scale revegetation of farmlands for maintaining arthropod biodiversity and their important ecological function. We examined seasonal differences in beetle assemblages in woodland remnants and four adjoining farmland uses in a highly modified agricultural landscape in southeastern Australia. The farmland uses were crops, fallows, and two restoration treatments (fine woody debris applied over harvested crop fields, and restoration plantings). Unexpectedly, overall species richness was significantly lower in remnants than in adjacent farmlands. Remnants and farmlands supported significantly different assemblages, with a third of species found in both habitats. Abundance responses were taxon-specific and influenced by interactions between land use and season. In particular, predator abundance was significantly higher in plantings and fallows during spring compared to summer. Detritivore abundance was significantly higher in the woody debris compared to the adjacent remnants. Herbivore abundance did not differ between remnants and farmlands over time. Complex responses provide strong support for a mosaic of land uses to effectively conserve different beetle groups. Species richness results suggest that further agricultural intensification, in farm fields and through the removal of remnant vegetation, risks reducing beetle diversity in this region. Maintaining farmland heterogeneity with a mix of low-intensity land uses, such as conservation tillage, crop–fallow rotation, restoration plantings, and the novel application of fine woody debris over cultivated fields, may provide seasonal refuge and resources for beetles. [ABSTRACT FROM AUTHOR]

There are many reasons why it is important that we find ways to conserve, and better utilize natural enemies of invertebrate crop pests. Currently, measures of natural enemy impact are rarely incorporated into studies that purport to examine pest control. Most studies examine pest and natural enemy presence and/or abundance and then qualitatively infer impact. While this provides useful data to address a range of ecological questions, a measure of impact is critical for guiding pest management decision-making. Often some very simple techniques can be used to obtain an estimate of natural enemy impact. We present examples of field-based studies that have used cages, barriers to restrict natural enemy or prey movement, direct observation of natural enemy attack, and sentinel prey items to estimate mortality. The measure of natural enemy impact used in each study needs to be tailored to the needs of farmers and the specific pest problems they face. For example, the magnitude of mortality attributed to natural enemies may be less important than the timing and consistency of that mortality between seasons. Tailoring impact assessments will lead to research outcomes that do not simply provide general information about how to conserve natural enemies, but how to use these natural enemies as an integral part of decision-making. [ABSTRACT FROM AUTHOR]

Areawide management has a long history of achieving solutions that target pests, however, there has been little focus on the areawide management of arthropod natural enemies. Landscape ecology studies that show a positive relationship between natural enemy abundance and habitat diversity demonstrate landscape-dependent pest suppression, but have not yet clearly linked their findings to pest management or to the suite of pests associated with crops that require control. Instead the focus has often been on model systems of single pest species and their natural enemies. We suggest that management actions to capture pest control from natural enemies may be forth coming if: (i) the suite of response and predictor variables focus on pest complexes and specific management actions; (ii) the contribution of 'the landscape' is identified by assessing the timing and numbers of natural enemies immigrating and emigrating to and from the target crop, as well as pests; and (iii) pest control thresholds aligned with crop development stages are the benchmark to measure impact of natural enemies on pests, in turn allowing for comparison between study regions, and generalizations. To achieve pest control we will need to incorporate what has been learned from an ecological understanding of model pest and natural enemy systems and integrate areawide landscape management with in-field pest management. [ABSTRACT FROM AUTHOR]

A greater understanding of the relative impact of insecticide use on non-target species is critical for the incorporation of natural enemies into integrated pest management strategies. Here we use a small-plot field trial to examine the relative impact of an insecticide on herbivores and predators found in soybean ( Glycine max L.), and to highlight the issues associated with calculating impact factors from these studies. The pyrethroid insecticide (Deltamethrin) caused a significant reduction in invertebrate abundance in the treated plots, and populations did not recover to pre-treatment levels even 20 days after spraying. To assess the relative impact of the spray on arthropods we first examined the mean difference in abundance in each plot before and after spraying. All herbivores decreased in abundance in the sprayed plots but increased in the control plots after spraying. Most predators (excluding hemipterans) showed a decrease in the control plots but a proportionally greater decrease in the sprayed plots. Next we examined the corrected percentage population reduction calculated using Abbott's formula. All predators (including Araneae) experienced a greater reduction (mean 87% ± 3.54 SE) than herbivores (mean 56% ± 4.37 SE) and Araneae alone (mean 71% ± 8.12 SE). The range in values across the plots varied and made categorising overall impact subjective for some taxa. Despite the constraints associated with small-plot trials, by using a combination of impact factors and examining community-level response across time, we did get some indication of the likely impact of this insecticide if used in a commercial situation. [ABSTRACT FROM AUTHOR]

Global environmental change is a pressing issue as evidenced by the rise of extreme weather conditions in many parts of the world, threatening the survival of vulnerable species and habitats. Effective monitoring of climatic and anthropogenic impacts is therefore critical to safeguarding ecosystems, and it would allow us to better understand their response to stressors and predict long-term impacts. Ecological networks provide a biomonitoring framework for examining the system-level response and functioning of an ecosystem, but have been, until recently, constrained by limited empirical data due to the laborious nature of their construction. Hence, most experimental designs have been confined to a single network or a small number of replicate networks, resulting in statistical uncertainty, low resolution, limited spatiotemporal scale and oversimplified assumptions. Advances in data sampling and curation methodologies, such as next-generation sequencing (NGS) and the Internet 'Cloud', have facilitated the emergence of the 'Big Data' phenomenon in Ecology, enabling the construction of ecological networks to be carried out effectively and efficiently. This provides to ecologists an excellent opportunity to expand the way they study ecological networks. In particular, highly replicated networks are now within our grasp if new NGS technologies are combined with machine learning to develop network building methods. A replicated network approach will allow temporal and spatial variations embedded in the data to be taken into consideration, overcoming the limitations in the current 'single network' approach. We are still at the embryonic stage in exploring replicated networks, and with these new opportunities we also face new challenges. In this chapter, we discuss some of these challenges and highlight potential approaches that will help us build and analyse replicated networks to better understand how complex ecosystems operate, and the services and functioning they provide, paving the way for deciphering ecological big data reliably in the future. [ABSTRACT FROM AUTHOR]