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The evaluation of the potential for newly arrived species to survive and the determination whether a founder population can become established and subsequently spread and cause negative impacts are crucial considerations when performing a pest risk assessment in plant health. Climate change has clear consequences concerning the potential range of pests, and their potential for spread and impacts. Despite its importance, no guidance exists to support the evaluation of whether and how climate change should be incorporated into pest risk assessment. This paper reviews how climate change has been considered so far, not only in the area of pest risk assessment but also in other domains and provides guidance on how its incorporation could affect the overall assessment. Furthermore, from this analysis, some possible solutions for incorporating climate change into pest risk assessment are provided, taking into account that its outcomes have profound political, economic, social and environmental implications. [ABSTRACT FROM AUTHOR]

Aim: We present a novel strategy for species distribution models (SDMs) aimed at predicting the potential distributions of range‐expanding invasive non‐native species (INNS). The strategy combines two established perspectives on defining the background region for sampling "pseudo‐absences" that have hitherto only been applied separately. These are the accessible area, which accounts for dispersal constraints, and the area outside the environmental range of the species and therefore assumed to be unsuitable for the species. We tested an approach to combine these by fitting SDMs using background samples (pseudo‐absences) from both types of background. Location: Global. Taxon: Invasive non‐native plants: Humulus scandens, Lygodium japonicum, Lespedeza cuneata, Triadica sebifera, Cinnamomum camphora. Methods: Presence‐background (or presence‐only) SDMs were developed for the potential global distributions of five plant species native to Asia, invasive elsewhere and prioritised for risk assessment as emerging INNS in Europe. We compared models where the pseudo‐absences were selected from the accessible background, the unsuitable background (defined using biological knowledge of the species' key limiting factors) or from both types of background. Results: Combining the unsuitable and accessible backgrounds expanded the range of environments available for model fitting and caused biological knowledge about ecological unsuitability to influence the fitted species‐environment relationships. This improved the realism and accuracy of distribution projections globally and, generally, within the species' ranges. Main conclusions: Correlative SDMs remain valuable for INNS risk mapping and management, but are often criticised for a lack of biological underpinning. Our approach partly addresses this concern by using prior knowledge of species' requirements or tolerances to define the unsuitable background for modelling, while also accommodating dispersal constraints through considerations of accessibility. It can be implemented with current SDM software and results in more accurate and realistic distribution projections. As such, wider adoption has potential to improve SDMs that support INNS risk assessment. [ABSTRACT FROM AUTHOR]

Pest risk assessment (PRA) comprises a set of quantitative and qualitative tools to protect productive ecosystems from the impacts of unwanted biological invasions., Self-organizing maps for pest profile analysis (SOM PPA) is a methodological approach aimed to support PRA. It is based on cluster analysis and extracts information out of current distributions of insect crop pests world-wide, allowing the analyst to generate a list of potential risk species for a target region., Self-organizing maps for pest profile analysis currently lacks of a measure of performance able to provide a level of confidence for its outputs., In this study, we investigate ζ diversity as an ecologically meaningful and generalizable metric of similarity. The application of ζ allowed us to quantify and thus reveal different levels of similarity across pest profiles., The use of ζ diversity applied to the SOM PPA provides an informative measure of uncertainty for the output of SOM PPA, thus adding major improvements to the methodology while only marginally increasing its complexity. [ABSTRACT FROM AUTHOR]

Biofuels are being pursued for their potential greenhouse gas (GHG) emissions benefits, among other reasons. In order to maximize productivity, avoid food-fuel conflicts, and minimize GHG emissions, many advanced biofuel feedstock crops, such as those desired by the aviation community, are under consideration based on traits, such as high biomass and/ or seed production, tolerance of marginal cultivation conditions, and short generation times, that may also be predictors of potential invasiveness risk. Biofuel-related invasion risks can be mitigated through careful feedstock crop selection and cultivation techniques developed from the invasion science literature. Existing voluntary best practices and some state and federal regulatory requirements in the United States recommend and/or require the use of such risk mitigation strategies. However, other policies and programs allow or provide incentives for biofuel production without conditions requiring the use of these strategies. We have synthesized information on the scientific knowledge of invasive species predictors and their use (or absence) in voluntary codes and U.S. regulatory frameworks and incentive programs. We highlight the existing tools and approaches for assessing invasion risk and avoiding the introduction and spread of invasive species as a result of biofuel feedstock cultivation. A well-coordinated combination of species restrictions, biosecurity requirements, and incentives for selection of less risky biofuel crops may effectively balance the desire for increased biofuel production while minimizing invasion risk. [ABSTRACT FROM AUTHOR]

Epitrix tuberis and E. cucumeris are major pests of potatoes in North America. E. tuberis causes the most serious damage because the larval feeding can cause superficial serpentine tunnelling on the surface of tubers as well as deeper pits. This damage can make crops unmarketable. By contrast, E. cucumeris mainly damages the foliage, and yield losses can occur when the adults reach high densities. In 2004, potato tuber damage characteristic of E. tuberis was seen in Portugal. In 2008, damage was more widespread and severe. E. cucumeris and a lesser known species, E. similaris, were recorded in affected fields. E. similaris has since been found across Galicia, Spain. E. similaris is thought to be the most likely cause of the tuber damage in Portugal, but it is possible that E. cucumeris or an as yet undetected Epitrix species is causing the damage. In 2010, a pest risk assessment for the Euro-Mediterranean area identified the movement of adults and pupae with seed or ware potatoes and associated soil as being the highest-risk pathways for the spread of Epitrix. In 2012, EU emergency measures were agreed to reduce the risk of further introductions and the rate of spread of these pests. [ABSTRACT FROM AUTHOR]

Different international plant protection organisations advocate different schemes for conducting pest risk assessments. Most of these schemes use structured questionnaire in which experts are asked to score several items using an ordinal scale. The scores are then combined using a range of procedures, such as simple arithmetic mean, weighted averages, multiplication of scores, and cumulative sums. The most useful schemes will correctly identify harmful pests and identify ones that are not. As the quality of a pest risk assessment can depend on the characteristics of the scoring system used by the risk assessors (i.e., on the number of points of the scale and on the method used for combining the component scores), it is important to assess and compare the performance of different scoring systems. In this article, we proposed a new method for assessing scoring systems. Its principle is to simulate virtual data using a stochastic model and, then, to estimate sensitivity and specificity values from these data for different scoring systems. The interest of our approach was illustrated in a case study where several scoring systems were compared. Data for this analysis were generated using a probabilistic model describing the pest introduction process. The generated data were then used to simulate the outcome of scoring systems and to assess the accuracy of the decisions about positive and negative introduction. The results showed that ordinal scales with at most 5 or 6 points were sufficient and that the multiplication-based scoring systems performed better than their sum-based counterparts. The proposed method could be used in the future to assess a great diversity of scoring systems. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the use of spatially explicit stochastic model in predicting Argentine ant spread over the heterogeneous landscape in New Zealand. The study indicates the influence of landscape suitability on the long-term spread of an invasive species. According to the study, the efforts to predict and evaluate species spread in invasion biology and conservation biology, diversity studies and climate change studies can be improved using the modeling and predictive mapping technology.

1. Many invasive species are introduced by trade, and there is a need for studies of pre-emptive measures to lower the risk of introductions, as post-establishment management is often extremely costly or nearly impossible. 2. In this study, we present a generic model for the first step of the invasion process for trade-imported pests, and further develop this model for potentially harmful bark beetles to assess the risk of introductions and alternative management options. 3. Our results suggest that introductions of bark beetles are likely, given present timber import practices, and that immigration may often go undetected by pheromone traps. 4. The most effective measures for reducing introduction risk were those aimed at isolating the storage from forest (storage enclosure, location) followed by those reducing the available resources for forest pests (debarking, timber irrigation, rapid processing), whereas delayed import was least effective. 5. Synthesis and applications: The generic model framework of species introductions presented here may easily be adapted to other import systems. The submodels of population dynamics and dispersal are also quite general, and we expect our qualitative results to hold in many cases, although the models were parameterized for bark beetles in this study. Our results suggest that detection of dispersal from storage to forests will be difficult, which implies that management actions should not be deferred until after detection in nature, as the pest species may then already be established and eradication may be too late. However, pre-emptive measures reducing propagule pressure at one or several stages of the introduction process, in particular isolation measures, may strongly reduce introduction risk. [ABSTRACT FROM AUTHOR]

1. When invasive species are first detected in a new environment there is often a demand for information about the potential for the organism to spread and create impacts. Uraba lugens (Lepidoptera: Nolidae) is an Australian native moth that has invaded New Zealand in what are presumed to be two separate episodes. After U. lugens was found in Auckland in 2001 aclimex™ model was prepared to gauge the potential for the moth to spread and inflict damage in New Zealand. Inconsistencies in fitting model parameters to the then known native distribution, indicated that the known native distribution was probably incomplete, and that the unknown part of its range was critical for defining its likely range limits in New Zealand. 2. A synthetic sex pheromone trapping survey was used to ascertain the altitudinal and upper rainfall range limits of U. lugens in part of its native range in Australia. The survey extended the known range of U. lugens into higher-altitude and higher-rainfall zones of Tasmania. We used the expanded distribution information to refine aclimex model, and to project the climate suitability for U. lugens with particular emphasis on New Zealand. 3. The projected climatic suitability of New Zealand indicates that the area likely to be at risk of invasion by U. lugens is considerably more extensive than was indicated from its historical distribution records in Australia. It now includes all the eucalypt forestry areas. Similarly, the global potential distribution covers the major eucalypt forestry regions of the world. 4. The minimum heat sum necessary to complete a generation for U. lugens that was associated with its range limits was considerably lower than that predicted by average development rates gained from constant temperature and daylength studies. Possible explanations for this anomaly are discussed. 5. Synthesis and applications. The lack of suitable data on the distribution of organisms is perhaps the single most common challenge for ecological climate modellers. Trapping along climatic gradients with a synthetic pheromone lure offers a cheap, rapid means of ascertaining the climatic distribution of suitable high profile insects. [ABSTRACT FROM AUTHOR]

The international seed trade is considered relatively safe from a phytosanitary point of view and is therefore less regulated than trade in other plants for planting. However, the pests carried by traded seeds are not well known. We assessed insects and fungi in 58 traded seed lots of 11 gymnosperm and angiosperm tree species from North America, Europe, and Asia. Insects were detected by X‐raying and molecular methods. The fungal community was characterized using high‐throughput sequencing (HTS) and by growing fungi on non‐selective agar. About 30% of the seed lots contained insect larvae. Gymnosperms contained mostly hymenopteran (Megastigmus spp.) and dipteran (Cecidomyiidae) larvae, while angiosperms contained lepidopteran (Cydia latiferreana) and coleopteran (Curculio spp.) larvae. HTS indicated the presence of fungi in all seed lots and fungi grew on non‐selective agar from 96% of the seed lots. Fungal abundance and diversity were much higher than insect diversity and abundance, especially in angiosperm seeds. Almost 50% of all fungal exact sequence variants (ESVs) found in angiosperms were potential pathogens, in comparison with around 30% of potentially pathogenic ESVs found in gymnosperms. The results of this study indicate that seeds may pose a greater risk of pest introduction than previously believed or accounted for. A rapid risk assessment suggests that only a small number of species identified in this study is of phytosanitary concern. However, more research is needed to enable better risk assessment, especially to increase knowledge about the potential for transmission of fungi to seedlings and the host range and impact of identified species. [ABSTRACT FROM AUTHOR]