Welcome to the IPRRG Webinar Series, a dynamic platform for engaging discussions on various aspects of pest risk modelling and analysis. Despite the virtual format, these webinars offer valuable insights and foster a sense of community among enthusiasts.

Recorded webinars are available indefinitely on the IPRRG YouTube channel. Each recording has a dedicated link in the table below for easy access.

IPRRG WEBINAR SERIES

Abstracts

IPRRG Webinar #1: Darren Kriticos

IPRRG Webinar Series and Pest Risk Model Database

Pest risk models have become key instruments in global biosecurity, helping to identify areas at risk of invasion by harmful alien organisms. The ability to discover and access pre-existing models is critical to ensure that the global biosecurity system operates efficiently and effectively. The development of pest risk modelling methods, particularly in a geographical context, has centred on collaborations between scientific researchers and pest risk management agencies. Most early pest risk models (and maps) were published in peer-reviewed scientific journals, which provided a degree of quality assurance and discoverability, at least in academic circles.  As the technology has matured and some biosecurity agencies have built in-house pest risk modelling capability, it is likely that a large share of recent modelling efforts have gone unpublished or ended up in “grey” literature, where they are far less accessible and discoverable. Undoubtedly, this can lead to global inefficiency as models are recreated for the same species. Most of these risk models are based on bioclimatic models, and most of them are global, or can be applied globally. Consequently, while they may be developed with the intention of identifying the risks in one region, they may be valuable for identifying risks to other jurisdictions.  This offers the potential for developed models to be used by biosecurity agencies that may not have the resources to develop their own models. To tackle these issues, IPRRG has developed an online database of pest risk models. The database is intended to support crowdsourcing of entries.  In this presentation, Darren explains the motivation to develop the database, demonstrates its operation and comments on the value of the platform for PRA praxis, and outlines some ongoing issues.

IPRRG Webinar #2: Matthew Everatt

Risk Assessment for Biological Control Releases

IPRRG Webinar #3: Katherine O’Donnell, Charles Lane and Chris Malumphy

The International Plant Sentinel Network

IPRRG Webinar #4: Tania Yonow

Accidental Pre-emptive Biocontrol for the Brown Marmorated Stinkbug?

The brown marmorated stinkbug (Halyomorpha halys) is a familiar topic for IPRRG, resulting in ‘Project Stinky’. This project had several facets, including understanding the potential distribution and impact of H. halys.The difficulties in managing this important horticultural pest has spawned interest in biological control programs. A critical question in classical biological control is the degree of overlap in the potential distributions of the agent and the target. This question can be addressed in part using pest risk assessment tools. This presentation describes work conducted to examine the niche overlap of two wasp parasitoids of H. halys, with particular interest in their potential distribution in Australia. One of the wasps, Trissolcus mitsukurii, was introduced to Australia in 1962 to control the green vegetable bug (Nezara viridula). One of our questions was the degree to which this wasp might play a role in controlling H. halys (if/when) it becomes established there. We began by examining the potential distribution of T. mitsukurii, which currently occurs in Asia (native range) and Australia and Italy (invaded ranges). We attempted some novel analyses with the CLIMEX Match Climates program to specifically account for the use of irrigation in agriculture, and then used the more standard CLIMEX Compare Locations program. Once we had the Compare Locations model for T. mitsukurii, we applied the same irrigation scenario to existing CLIMEX models for both H. halys and the second key parasitoid, Trissolcus japonicus, and examined the range overlaps of the three species. All species are projected to expand their current ranges, with sympatric ranges in most invaded regions. Trissolcus japonicus has recently been shown to be polyphagous, but nonetheless has been approved for release in New Zealand should H. halys become established there. While it is unlikely to be approved for intentional release in Australia, it is also highly invasive and will likely spread to Australia unassisted. This suggests that both Trissolcus species should be able to help mitigate the impacts of H. halys as it spreads, and is supported by recent work in Italy and Switzerland, showing the concurrent spread of both T. mitsukurii and T. japonicus alongside that of H. halys.

IPRRG Webinar #5: Andrew Robinson

Context Is Everything: Sampling for Area Freedom

ISPM 31 prescribes an approach to sampling for proof of freedom that is based on specifying a probability that the pest will be detected if it is present at a nominated prevalence. However, the approach provides no insight as to how the probability or prevalence should be set. We assert that agencies should seek to minimise the net expected costs of surveillance and the expected damages that would occur, should the pest still be present. By wrapping the existing approach in an economic framework, we can shed light on the implications of different choices from the point of view of making decisions. We illustrate the method’s implementation using information contained in two historical proof of freedom proposals conducted in Queensland for cocoa pod borer (Conopomorpha cramerella) and citrus canker (Xanthomonas axonopodis), and contrast the differences in the required levels of effort.

IPRRG Webinar #6: Catriona Duffy

Using Hierarchical Clustering to Identify High Risk Pests to Sitka Spruce

The presence of a species within a specific region indicates that suitable biotic and abiotic conditions exist for that pest. Therefore, grouping regions based on a species’ presence or absence indicates a level of similarity of those same conditions. This is the fundamental assumption underpinning the application of hierarchical clustering to assemblages of pests of Sitka spruce in order to identify high risk pests to Ireland. A region’s pest assemblage is the result of a multitude of complex biotic (e.g. host) and abiotic (e.g. climatic) factors within that area and that these pest profiles act as a proxy for these factors when attempting to group ‘like’ pest organisms together. Presence/absence data for 1000 pests across 386 regions globally were clustered based on their similarity of pest assemblages, to provide an objective examination of the highest risk pests to Irish forestry. Outputs from the analysis suggest that the highest risk pests to Ireland’s Sitka spruce plantations will originate from within Europe. This approach is useful from a ‘horizon scanning’ and resources perspective, as it aids in identifying pests for further detailed analysis using Pest Risk Analysis (PRA).

IPRRG Webinar #7: Debbie Hemming

Integrating Microclimate Models into Pest Risk Analysis

The UK Met Office and University of Exeter have been collaborating closely with the UK Department for Environment, Food and Rural Affairs’ (Defra’s) Plant Risk and Horizon Scanning team to improve the use of climate data and climate modelling for informing UK pest risk assessment. We present a brief overview of this work and highlight recent microclimate modelling efforts to better understand the climate at locations relevant for pest life-cycle development.

IPRRG Webinar #8: Ruan C. de M. Oliviera

Current and Future Potential Distributions of Helicoverpa punctigera (Lepidoptera: Noctuidae): Is This the Next FAW?

Helicoverpa punctigera (Wallengren), the native budworm, is an important highly-polyphagous pest that has caused serious damage on a wide variety of crops in Australia. In Australia, its range overlaps that of its congener, Helicoverpa armigera (Hübner), a notorious invasive pest globally. We used CLIMEX, a bioclimatic niche modelling software package, to estimate the potential geographical distribution of H. punctigera under current and future climates (A1B scenario). Under both current and future climate conditions, the model indicates that H. punctigera could establish throughout the tropics and subtropics. Comparing the potential distributions under each climate scenario revealed that in the future its potential distribution is likely to shift poleward and into higher altitudes, into areas that are currently too cold as observed in the South of Brazil, Europe, North America, South East Asia, and South Pacific Islands including New Zealand. The projected potential distribution can inform pre- and post-border biosecurity strategies for the management of this pest in each country.

IPRRG Webinar #9: Melanie Newfield

The Use of Risk Assessment and Decision Making in the Biosecurity System

• The research programme “He Tangata, He Taiao, He Ōhanga” (translated as “the people, the environment, the economic”) aims to develop a new biosecurity risk assessment framework that incorporates information from a holistic set of values.
• Before researchers developed a new framework, I reviewed literature and spoke to decision makers to determine what frameworks, models and tools are already available to support risk assessment and decision making in the biosecurity system. I also looked more generally at decision makers’ attitudes towards risk assessment.
• While there are many frameworks, models and tools for both risk assessment and decision making, I found that they are not widely used for biosecurity decision making.
• Many published frameworks for risk assessment and decision making are developed for specific purposes or to answer specific questions and can’t be adopted for other purposes without modification. Some of the stated reasons that frameworks aren’t used are similar to reasons that models weren’t used to make decisions in conservation.
• For the decision makers I spoke to in the study, trust is central to the worth that they place on risk assessment, particularly trust in the people doing risk assessments. Rather than some decision makers trusting risk assessors and some decision makers not trusting them, the majority of decision makers trusted some risk assessors and not others.
• The design of frameworks, models and tools needs to address more than just developing tools. The design also needs to consider those who will directly use the framework (for example, risk assessors), and those who will use the results of that framework (for example, decision makers who make decisions based on risk assessment). In particular, the framework needs to be developed in a way that builds trust between those developing the framework and those using the framework.

IPRRG Webinar #10: Antigoni Akrivou

Potential Global Distribution of Aleurocanthus woglumi (Hemiptera: Aleyrodidae) and the Risk Posed to Europe

Citrus blackfly, Aleurocanthus woglumi Ashby, is an agriculturally important polyphagous pest due to the economic losses it causes to citrus and many other plants. As climate changes, the areas at risk from biological invaders shift and so it is important for biosecurity managers to be aware of the emerging threat patterns as they institute phytosanitary measures. We used CLIMEX – a process-oriented climatic niche model – to model the potential global distribution of A. woglumi under an historical climate scenario (centred on 1995) and found that there are current and emerging risks in every continent. Moreover, CLIMEX simulation under the RCP 8.5 climate change scenario for 2050 indicates that its potential distribution is projected to increase across all continents except Africa. In this scenario, the risk of A. woglumi establishing in Europe is high.

IPRRG Webinar #11: Denys Yemshanov

Bi-Level Governance in Pest Survey Campaigns: How Can Game Theory Help?

Large-scale delimiting surveys are critical for detecting the extent of novel pest invasions and often undertaken at different governance levels. In this study, we consider a two-level hierarchical planning of spatial pest surveys – the central government agency with a mandate to report the spatial extent of pest invasion, and regional governments concerned about the possible threat of an outbreak. Central agency plans delimiting pest surveys across multiple administrative subdivisions (counties) in which regional governments could participate in conducting the pest surveys if funds become available. Our goal is to find the optimal levels of cooperation between the central agency and regional governments when the central agency may allocate a portion of the funds to regional governments to reduce the survey cost. We propose a bi-level Stackelberg game model that finds optimal levels of cooperation between two levels of government in pest survey campaigns. The model finds the budget portion and regions where it is optimal to devolve a portion of survey funds to regional governments to improve the survey efficiency.

We apply the model to surveillance of hemlock woolly adelgid, a harmful pest of hemlock trees in Ontario, Canada. Our bi-level model solutions help anticipate the under-performance of surveys conducted by regional governments because their goals do not fully align with the central agency’s survey objective. The bi-level approach offers a realistic assessment of the governance hierarchies in large-scale delimiting pest surveys because it helps the central agency to account for the utility preferences of the regional governments and endogenize their survey decisions concerning their preferences. The methodology can be adapted to explore cost-sharing strategies in governance hierarchies in other regions and administrative jurisdictions.

IPRRG Webinar #12: Anna Szyniszewska

Fruit Flies in a Warming World – Models and Evidence of Range Expansion

We reviewed and refined a published CLIMEX model for Medfly, Ceratitis capitata, a fruit fly of economic importance. We considered recently published experimental results on its ecophysiology and geographic observations in Europe. To assess the model fit, and to aid in interpreting the meaning of the new European distribution records we used the CRU TS4 climate time series dataset to explore the temporal patterns of climate suitability from the 1970s to the 2010s. At selected bellwether sites in Europe we found statistically significant trends in increasing climate suitability, as well as a substantial northward expansion in the modelled potential range. Recent geographical records in Italy and France appear to represent a mixture of established and ephemeral populations, which is consistent with reports of the seasonal range dynamics of C. capitata in Europe. To gauge the generality of our findings, we applied the same techniques to the climate suitability dynamics of Queensland Fruit Fly, Bactrocera tryoni in Australia. We found patterns of poleward expansion in the potential distribution of B. tryoni that reflect the patterns of observations. We also found statistically significant trends in suitability at marginal sites.

IPRRG Webinar #13: Sonia Baldi

Pest Risk Register and Integrated Risk Assessment Tool for ADAFSA

The Emirate of Abu Dhabi, which is one of the seven Emirates that compose the United Arab Emirates (UAE), accounts for 80% of the agricultural sector along the country comprising 24.000 farms. The agricultural sector is held by the Abu Dhabi Agriculture & Food Safety Authority (ADAFSA) which is the local authority in charge of agriculture, food safety, food security and biosecurity in the Emirate of Abu Dhabi. It aims to develop a sustainable agriculture and food sector and protect the health of animals and plants to enhance the biosecurity and achieve food security. In addition, the authority is responsible for preparing plans, programs and activities in the field of agriculture, food safety and food security.

ADAFSA adopts the integrated farm to fork ‘food chain’ approach as a means of ensuring coherence and integration of regulatory and non-regulatory risk management measures across the entire food chain.

ADAFSA’s Integrated Risk Management Framework, based on risk analysis, is an essential tool to provide a consistent approach for making decisions on any government intervention and action in response to animal, plant and human health related issues.

In this webinar session, engineer Sonia Baldi, who is a risk analyst in the Policies and Legislation Division (ADAFSA), will give more insights about the Integrated Risk management Framework and will talk about the Pest Risk Register, which is a tool for government and decision makers to prioritize resources against pests and diseases which threaten our main crops. She will also develop more the context of risk assessment in plant health and its role in the management of the most important pests and diseases in the Emirate of Abu Dhabi.

IPRRG Webinar #14: Emma Hudgins

New Perspectives in Urban Forest Invader Management

Urban trees are important nature-based solutions for future wellbeing and livability, but are at high risk of mortality from invasive insects and pathogens. To plan effective mitigation, managers must know which tree species in which communities will be at the greatest risk, as well as the highest-risk species. This presentation will cover four different projects relating to urban forest health in the face of species invasions. First, I will summarize an economic impact assessment on United States (US) street tree mortality due to invasive insects. This approach combined models of street tree populations in ∼30,000 communities, species-specific spread predictions for 57 invasive insect species, and estimates of tree death due to insect exposure for 48 host tree genera. We estimated that 1.4 million street trees will be killed by invasive insects from 2020 through 2050, costing an annualized average of US$ 30M. Further, 90% of all mortality will be due to emerald ash borer (Agrilus planipennis, EAB), which is expected to kill virtually all ash trees (Fraxinus spp.) in >6000 communities. Secondly, I will discuss a recent project that has reformulated this impact model as an optimal control framework to determine the ideal management strategy for urban tree persistence. We found that the best management strategy always included a combination of site-focused (biological control) and spread-focused (quarantine) management measures, and that failing to use a mixed strategy could result in losses of upwards of one million street trees in the next 30 years. Thirdly, I will discuss the link between forest biodiversity and pest susceptibility, where a phylogenetic model indicates that diverse tree plantings reduce the probability that invaders will establish. Finally, I will discuss preliminary findings from a very recent ‘new perspectives in forest invader management’ workshop, featuring experts across the invasion response, including Indigenous knowledge holders.

IPRRG Webinar #15: Bénédicte Lebas

The International Seed Federation Regulated Pest List Database – An Overview

​The Regulated Pest List Initiative (RPLI) of the International Seed Federation (ISF) was initiated in 2007 with the aim of facilitating the harmonization of phytosanitary requirements for seed by developing a database with information on pests that are regulated on seed of internationally traded (vegetable) crops. Information in the database is based on a thorough scientific assessment to determine whether seed is a pathway for the regulated pest following the principle of International Standards for Phytosanitary Measures (ISPM). Pest management practices are provided for pests for which seeds can be a pathway, based on the knowledge and experience of the seed industry. To date, the database contains 15 crop specific pest lists with over 1,300 regulated pests, of which 995 (74%) were concluded either seed is not a pathway (47.5%) or crop is not a host of the pest (26.5%) (https://worldseed.org/our-work/phytosanitary-matters/pest-list/). Predictable international movements of seeds rely on phytosanitary measures that are scientifically justified. The overregulation of seeds hampers import and export of seeds.

IPRRG Webinar #18: Joseph Stinziano

Validating Standardized Mahalanobis Distance as a Species Distribution Model for Invasive Alien Species

Species distribution models (SDMs) can be used to identify areas of climatic suitability for invasive alien species under present and future climate conditions. However, these models face issues including correlations between climate variables and results that are not often validated. We have implemented a standardized multivariate distance metric as an SDM, allowing for the rapid production of climate-suitability maps with reliability metrics. This approach characterizes the observed multivariate climate envelope by taking advantage of the correlation between climate variables and identifies areas where the climate is outside the range of the observed climate envelope. We include built-in metrics of reliability, including measures of variation across climate models. Model outputs include climate suitability maps, measures of variability, and most importantly covariates, to assess model reliability and underlying environmental drivers of the results. Using a list of 9 species from CFIA’s regulated pest list, we demonstrate that this method achieves a high level of accuracy (greater than 80%) for determining climate suitability for North American plant pest invasions. This suggests that the model is suitable for identifying areas of North America that are susceptible to future invasions. We show that many of the errors occur at the edge of climate-suitable areas, where we would expect greater uncertainty in model predictions due to potential over-constraining and geospatial averaging. This standardized multivariate distance model can be used to assess the potential area for invasion by a plant pest in minimal time (±1 hr) with minimal data (standard bioclimatic variables and species presence data).

IPRRG Webinar #19: Ultan O’Donnell

Understanding Observable Historical Pest Dynamics Through a Data Rescue Approach

In this webinar, Ultan O’Donnell, a final-year PhD scholar based in University College Dublin, explores Ireland’s historical forestry pest dynamics, presents opportunities to recover and use long-term data through data rescue methods, and recommends simple changes to improve the usability of reported invasive species data going forward. His first thesis chapter, which shares its title with this webinar, was recently published in the journal Biological Invasions.

IPRRG Webinar #20: Barney Caton

Risk-Based Sampling (Non-Propagative Goods) at U.S. Ports of Entry

IPRRG Webinar #21: Helena Romero Marín

DNA Barcoding for Pest Detection in Subtropical Crops

The expansion of subtropical crop cultivation in Mediterranean regions such as southern Spain is reshaping agricultural landscapes and creating new opportunities for pest establishment. Introduced crops can act as entry points for non-native arthropods and alter the dynamics of native pest complexes, posing risks to biodiversity and agricultural productivity. Anticipating these risks requires sensitive tools to detect shifts in insect communities at an early stage.

In this study, Helena and her team used Malaise traps and DNA barcoding to monitor insect macrocommunities in subtropical crops and adjacent native habitats. This molecular approach enabled broad community profiling and the detection of both potential pest species and natural enemies. However, their results also revealed an important limitation, as certain pest species known to be present in the field were not detected in the barcoding analysis, underscoring challenges related to sampling methods, and detection thresholds.

These findings demonstrate both the potential and the current constraints of molecular tools for pest detection. By identifying these gaps, Helena emphasises the need for integrating DNA barcoding with complementary approaches in pest risk assessments. Such combined frameworks can improve early-warning capacity, strengthen pathway analyses, and ultimately support decision-making for managing emerging threats associated with crop introductions.

IPRRG Webinar #22: Anastasia Korycinska