Purpose of the Review: One of the major threats to tree health, and hence the resilience of forests and their provision of ecosystem services, is new and emerging pests. Therefore, forest health monitoring is of major importance to detect invasive, emerging and native pest outbreaks. This is usually done by foresters and forest health experts, but can also be complemented by citizen scientists. Here, we review the use of citizen science for detection and monitoring, as well as for hypothesis-driven research and evaluation of control measures as part of forest pest surveillance and research. We then examine its limitations and opportunities and make recommendations on the use of citizen science for forest pest monitoring.Recent Findings: The main opportunities of citizen scientists for forest health are early warning, early detection of new pests, monitoring of impact of outbreaks and scientific research. Each domain has its own limitations, opportunities and recommendations to follow, as well as their own public engagement strategies. The development of new technologies provides many opportunities to involve citizen scientists in forest pest monitoring. To enhance the benefits of citizen scientists’ inclusion in monitoring, it is important that they are involved in the cocreation of activities.Summary: Future monitoring and research may benefit from tailor-made citizen science projects to facilitate successful monitoring by citizen scientists and expand their practice to countries where the forest health sector is less developed. In this sense, citizen scientists can help understand and detect outbreaks of new pests and avoid problems in the future.

• Ceratitis capitata is not a quarantine pest in the European Union • rapid identification of C. capitata at port of entry is needed • LAMP assays were developed that could aid in the rapid discrimination of C. capitata from related species

This study investigated the efficacy of various traps differing in colour (green or yellow), presence or absence of decoys (dead Agrilus planipennis) or design (commercial MULTz or multifunnel traps, and homemade bottle- or fan-traps) for monitoring European Buprestidae in deciduous forests and pear orchards. Over two years, we collected 2220 samples on a two-week basis from 382 traps across 46 sites in Belgium and France. None of the traps proved effective for monitoring Agrilus sinuatus in infested pear orchards (17 specimens captured in 2021, 0 in 2022). The decoys did not affect the catch rates whatever the trap model, colour, buprestid species or sex. The fluorescent yellow traps (MULTz and yellow fan-traps) tended to be more attractive than the green traps (green fan-traps and, to a lower extent, multifunnel green traps). Most Agrilus species showed similar patterns in mean trap catches, with the exception of Agrilus biguttatus, which had the largest catches in the green multifunnel traps. Finally, we observed a high variation in catch rates between localities: the site explained 64% of the catches variance, while the tree within the site and the type of trap explained only 6–8.5% each. In many sites, we captured very few specimens, despite the abundance of dying mature trees favourable to the development of Buprestidae. For the early detection of non-native Buprestidae, it therefore seems essential to maximise the number of monitoring sites. Due to their cost-effectiveness, lightweight design, and modularity, fan-traps emerged as promising tools for buprestid monitoring. The study’s findings extend beyond European fauna, as a preliminary trial in Canada suggested that yellow fan-traps could also improve captures of non-European buprestid species and catch species of interest such as Agrilus bilineatus (a species on the EPPO A2 list of pests/pathogens recommended for regulation in the EU).

BACKGROUND: Two jewel beetle species native to Europe, the cypress jewel beetle, Lamprodila (Palmar, Ovalisia) festiva L. (Buprestidae, Coleoptera), and the sinuate pear tree borer, Agrilus sinuatus Olivier (Buprestidae, Coleoptera), are key pests of ornamental thuja and junipers and of orchard and ornamental rosaceous trees, respectively. Although chemical control measures are available, due to the beetles’ small size, agility, and cryptic lifestyle at the larval stage, efficient tools for their detection and monitoring are missing. Consequently, by the time emerging jewel beetle adults are noticed, the trees are typically significantly damaged. METHODS: Thus, the aim of this study was to initiate the development of monitoring traps. Transparent, light green, and purple sticky sheets and multifunnel traps were compared in field experiments in Hungary. RESULTS: Light green and transparent sticky traps caught more L. festiva and A. sinuatus jewel beetles than non-sticky multifunnel traps, regardless of the larger size of the colored surface of the funnel traps. CONCLUSIONS: Although light green sticky sheets turned out to be optimal for both species, using transparent sheets can reduce catches of non-target insects. The key to the effectiveness of sticky traps, despite their reduced suitability for quantitative comparisons, may lie in the behavioral responses of the beetles to the optical features of the traps.

Natural enemy surveys, especially for indigenous anthocorid predators of sugarcane thrips Fulmekiola serrata Kobus, were completed between 2008 and 2013 in and around sugarcane fields in the Mpumalanga and KwaZulu-Natal provinces of South Africa. Four Orius species were recorded during the surveys. First records for South Africa of Orius tantillus (Motchulsky) and Orius naivashae (Poppius) were made, and the presence of Orius thripoborus (Hesse) and Orius brunnescens (Poppius) in the country was confirmed. For each species, habitat and climate preferences are described. Orius thripoborus was the only anthocorid natural enemy which was observed preying on the sugarcane thrips in the field.

Bactrocera dorsalis (Hendel) is a major insect pest of commercial fruit and a quarantine priority in the European Union (EU). This tephritid species was previously recorded in Austria, France, and Italy, with more recent detections in Greece. In 2023 and 2024, B. dorsalis adult males were captured by the Federal Agency for the Safety of the Food Chain (FASFC) using traps placed in community gardens and produce markets in Belgium. Morphological identification confirmed the specimens as B. dorsalis. Genomes of trapped adults were sequenced, as well as a historical set of B. dorsalis larvae intercepted by FASFC from imported fruit. A nuclear single-nucleotide polymorphism (SNP) analysis revealed that three Belgian B. dorsalis adults originated from Africa, while eight others were of Asian origin. In contrast, almost all FASFC intercepted larvae had an African origin. A discriminant analysis of principal components (DAPC) of the “Folmer” region of the mitochondrial cytochrome c oxidase subunit I (COI) gene largely confirmed the SNP analysis but also indicated that, in a few cases, mitonuclear discordance may confound origin tracing. To enable geographic origin tracing in a laboratory setting, a diagnostic set of nuclear SNPs was developed. The DAPC was also implemented in a streamlined R-script, allowing origin assignment using a mitochondrial COI barcode. To conclude, our study reveals independent occurrences of B. dorsalis in Belgium and provides important tools for origin tracing of this quarantine pest.