Citizen science (CS) is increasingly used for research, environmental monitoring and policy input while enhancing participants' skills and well-being. However, it remains unevenly distributed globally, with limited presence in low- and middle-income countries, e.g. India, that are vulnerable to climate risks. This systematic review, following the PRISMA framework, identified 58 initiatives from academic and non-academic sources and analysed the scope and drivers of environmental and ecological CS projects in India. The findings reveal disparities in project diversity, geographic distribution and levels of participant engagement across the scientific process. Projects are concentrated in more affluent states and are predominantly biodiversity-focussed, with fewer addressing local socio-environmental concerns, highlighting the untapped potential of CS to address socio-environmental challenges in India. To scale its impact, we recommend strengthening linkages with government and academia, expanding thematic coverage and designing locally relevant projects with higher levels of public engagement aligned with policy needs.

ABSTRACT Formidable obstacles constrain elementary teachers’ efforts to provide science instruction that creates opportunities for students to engage with science. These include limited instructional time, inadequate access to high-quality instructional materials and professional learning, and teachers’ self-efficacy. Citizen science, or community science, supports teachers by offering ways to engage students in science and in collecting and interpreting data connected to students’ lives. While citizen science projects emphasise gathering accurate data fundamental for scientific success, they may not align with teacher needs. Using Remillard’s model of teachers’ participatory relationship with curriculum materials, we studied how project-specific educative supports could facilitate teachers’ use of citizen science projects in formal settings. We selected two projects and developed educative support materials. We present data from 52 teachers in a randomised controlled trial investigating (1) how teachers used the materials and (2) how the materials impacted use. Access to project-specific educative supports has a large positive effect on teachers’ and students’ use, and teachers value some supports more than others. We situate our work in research on teachers’ relationship with instructional materials, design of educative curriculum materials, and school-based citizen science. We discuss the implications for project designers, science education researchers, and science teacher educators.

Microsporidia are a diverse group of fungal parasites that infect humans and agriculturally important animals. Caenorhabditis elegans has emerged as a powerful host for investigating microsporidian biology, yet how ecological factors such as geography, seasonality, temporality, and sample substrate impact infection of C. elegans and other nematodes remains unclear. To address this, we developed a citizen scientist network, Worms About Town, to annually survey wild nematodes for microsporidia across Toronto, Canada. Here, we describe results from the first year (2024) of the project. One hundred twenty-seven environmental samples from various plant substrates were collected, 60 of which contained wild nematodes and four of which were infected with microsporidia. Two isolates of Nematocida homosporus, a known generalist microsporidian of nematodes, were identified. The other two microsporidia isolates belong to undescribed species of Pancytospora and Enteropsectra, genera distantly related to human-infecting microsporidia. Three nematode isolates of the Caenorhabditis genus were discovered, including two isolates of C. elegans, a species not previously reported in Ontario. Both N. homosporus isolates were found in C. elegans, and one can infect a laboratory strain of C. elegans. Our study expands knowledge of natural nematode-microsporidia diversity and provides a framework for systematically investigating how ecological factors shape this host-parasite system.

ABSTRACT Citizen science approaches, which engage the public in scientific research tasks, can empower adolescents and young adults (AYA) to generate ideas that solve problems in their communities. However, little is known about why AYA choose to partner on HIV citizen science studies, their experiences, or the impact of engagement. This study assessed AYA partners’ engagement as Youth Research Collaborators (YRC) on a citizen science HIV stigma reduction intervention in Kazakhstan. Nineteen YRC (ages 15–29) completed reflective interviews focused on the relevance of the research, perceptions of their experience, impacts, and recommendations for future studies. Partnering on an HIV citizen science study was culturally and personally relevant to YRC. Most enjoyed the autonomy to implement their ideas and influence decisions, though some worried about their ability to make useful contributions. In general, YRC felt valued and supported as members of the research team. Impacts included gains in knowledge, skills, professional benefits, emotional fulfillment, and gratitude for the potential to make an altruistic contribution. Recommendations for future studies included ways to expand citizen science projects and increase accessibility for AYA from diverse backgrounds. Findings suggest that assessing AYA engagement in participatory studies can increase research accountability and provide insights that improve partnerships.

Citizen science data reliability enhancing scientific research: insights from an 11-year study in the Mediterranean Sea

Craticulascientiacivica Moyón & S. Blanco, sp. nov., is a new diatom species discovered during the CiDIA-micro citizen science project at the University of León, Spain, which evaluates the environmental impact of biodegradable packaging on periphytic diatom communities. This initiative involved secondary school students and teachers in sampling experimental aquaria inoculated with natural benthic algae from Laguna Sentiz (León, Spain), revealing the novel taxon in a control treatment under alkaline conditions (pH 9, low nutrients). Valves are linear-lanceolate, panduriform, with concave margins and protracted rostrate apices, measuring 32.0–35.7 μm long and 3.9–6.3 μm wide. Striae are uniseriate, 18–19 in 10 μm, and weakly radiate, with circular central areolae (37–46 in 10 μm) transitioning to elliptical forms apically. The raphe is filiform, with expanded, unilaterally deflected proximal endings and terminal hooks extending onto the mantle. Teratological forms were found in 26% of individuals, featuring deformed outlines, misaligned raphe, and aberrant copulae, possibly linked to culture conditions despite the absence of chemical stressors. Morphologically, C.scientiacivica aligns with Craticula (Stauroneidaceae) via its shallow mantle, apically elongated external foramina, and deflected central raphe endings, but its unique panduriform shape and dimensions distinguish it from congeners. Molecular data are pending, but its occurrence in a single experimental tank suggests aerial propagule dispersal. This discovery underscores the role of citizen science in uncovering hidden biodiversity, bridging education and taxonomy in diatom research.

While citizen science (CS) has gained global reputation as a valuable participatory research methodology, over the last decade its demarcation is still somewhat controversial. Attempts to reach a precise definition of CS have resulted in several sets of criteria, principles and minimum requirements without universal normative power. In search of a transparent and just selection process, platforms offering access to CS projects started to define their own selection criteria. In 2017, the Austrian CS community co-created a set of 20 quality criteria to define minimum requirements for CS projects to be listed on the national platform Österreich forscht. After more than five years of applying the criteria, we reflect on the implications for CS projects in Austria. Our mixed method approach of qualitative and quantitative analysis across 103 projects shows no disadvantage for specific research domains or types of institution, but certain challenges for project coordinators to apply all criteria to their projects. The analysis suggests an overall improvement of projects, especially in regard to their ‘citizen scientificity’, meaning that the criteria helped them to better distinguish themselves from other scientific methods, improving their engagement, communication and open data management.

Practical lessons from microbiome citizen-science projects.

BackgroundThe emergence and spread of TBDs present major challenges. Exposure to tick bites in mainland France is mainly documented through local studies or citizen science projects. According to the 2024 French national survey, about 15% bitten individuals consult a healthcare professional. National-level data from general practice are needed to better describe tick bite epidemiology.Main objectiveTo estimate the incidence of patients consulting general practitioners (GPs) for a tick bite and to describe their characteristics, their management and the context of the bite.MethodWe conducted a study using the French Sentinelles network, a national surveillance system that collects data from a sample of GPs. From May 2023 to April 2024, an indicator ‘Consultations with a tick bite’ was added to the routine data collection, in addition to the ongoing Lyme borreliosis surveillance. National and regional incidences were estimated using a hierarchical Bayesian model incorporating spatial and temporal dependencies to account for data sparsity. A tick collection was also carried out in order to identify the ticks and analyse the pathogens they might transmit.ResultsA total of 179 GPs participated and reported 483 consultations for a tick bite episode. The estimated national incidence was 324 cases per 100,000 population (95% CI [290; 369]) over the study period, peaking in May-June 2023. Incidence was highest in the southwestern and northeastern France. Children represented one quarter of cases and nearly half of patients consulted in general practice without clinical symptoms. Of the 86 ticks analysed, 24% tested positive for at least one of the pathogens tested.ConclusionThese findings provide new insights into the epidemiology of tick bites in France and contribute to assessing population exposure to ticks, informing future prevention and public health strategies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-026-27498-8.

Considerations for the design of impactful citizen-science projects in microbiome research

Abstract We report the discovery and spectroscopic classification of a new cataclysmic variable (CV), GALEX J211240.9–422959 (Gaia DR3 source ID 6580244356829724928). This object was initially identified as a source exhibiting strong mid-infrared variability in Wide-field Infrared Survey Explorer (WISE) time-series data by a volunteer participating in the Exoasteroids citizen science project. Prompted by this strong variability at 3–5 μ m, we obtained a follow-up optical spectrum using the Gemini Multi-Object Spectrograph at the Gemini South Observatory. The resulting spectrum displays a blue continuum dominated by strong, broad emission lines of the hydrogen Balmer series and neutral helium, spectral signatures characteristic of an accreting white dwarf in a CV system. The GALEX J211240.9–422959 WISE light curve contains an infrared outburst peaking in 2016 that lacks a corresponding optical outburst. More follow-up is needed to understand the physical mechanism driving this object’s infrared and optical behavior.

This study examined how a school garden in Vijes, Colombia, functions as a habitat for pollinators and a space for experiential education. Primary school students recorded 208 floral visits in four plots (ornamental, medicinal, fruit, and crop) in three weeks, with limited observation time. Activity was dominated by Tetragonisca angustula (49%) Apis mellifera (36%). Pollinators mainly visited the ornamental plot, particularly Zinnia peruviana, and Cucurbita maxima in the crop plot. Participation in monitoring fostered ecological awareness, teamwork, and biodiversity appreciation. The project shows how citizen science approaches can transform school gardens into living laboratories for biodiversity conservation and sustainability education.

Social media influencers (SMIs) are important information sources for socio-political topics among adolescents. Adolescents may even ascribe digital super peer perceptions to some SMIs for sharing sensitive information (e.g., LGBTQ+ issues, health) that may be unavailable or uncomfortable to discuss among their regular peers. However, it remains unclear which socio-political topics adolescents encounter and which differential susceptibility factors predict perceived SMI trustworthiness or perceived societal relevance of the information they provide. To address these gaps, we conducted a collaborative citizen science project with N = 386 adolescents aged 12 to 18. Adolescents contributed and indicated their appraisal of socio-political posts by SMIs about a range of socio-political topics, including sensitive issues. Attribution of altruistic motives to SMIs, less exposure to socio-political SMI content, and the presence of opinions in such content emerged as important factors explaining why adolescents may perceive SMIs as trustworthy and their socio-political information as societally relevant.

Lethal specimen collection followed by destructive tissue sampling is employed routinely in earthworm DNA barcoding studies. However, this approach may be ecologically disadvantageous and risks public disengagement with biodiversity and barcoding research due to negative emotional associations, particularly in Citizen Science (CS) projects. The study describes the performance of swab sampling as a non-lethal and emotionally-adaptive alternative to tissue sampling in earthworm barcoding. Three DNA collection methods, namely swab sampling with silica-based DNA extraction (Swab-QIAGEN), tissue sampling with silica-based DNA extraction (Tissue-QIAGEN), and tissue sampling with resin-based DNA extraction (Tissue-Chelex) were compared for generating cytochrome c oxidase I (COI) barcodes from 40 adult earthworms. All methods showed comparably high PCR amplification success rates (Tissue-Chelex = 100%; Tissue-QIAGEN = 100%; Swab-QIAGEN = 97.5%), except for one recalcitrant Swab-QIAGEN sample. Considering the pool of successfully amplified samples, the sequencing success rate for the Tissue-Chelex, Tissue-QIAGEN, and Swab-QIAGEN methods was 82.5% (33/40), 87.50% (35/40), and 66.7% (26/39), respectively-with 25 of 119 barcodes flagged as sequencing/methodological failures due to unusable contigs, stop codons/indels, or contamination. Although swabs showed lower success rates overall, they produced the greatest proportion of reference-quality barcodes among functional sequences (80.8%; 21/26), indicating their potential for DNA collection compared to Tissue-Chelex (75.8%; 25/33) and Tissue-QIAGEN (68.6%; 24/35). All intra-specimen barcodes, excluding contaminations, received consistent homology-based taxonomic assignments with average similarity percentage above 99%, corresponding to a 90.4% morphospecies-genetic data concordance rate. The average intra-specimen pairwise sequence percentage identity was above 99% (i.e., < 0.1% average sequencing error) across all methods, and no method-specific clustering was observed in the COI barcode tree. Overall, the results indicated a high degree of interoperability and agreement between swab and tissue sampling methods for recovering the same or nearly-identical haplotypes with consistent taxonomic identities from each specimen. However, the swabbing methodology requires standardization before it can be confidently utilized in CS-based earthworm DNA barcoding projects.

Because of their historical and architectural richness, since 1991 the banks of the Seine in Paris have been listed as a UNESCO World Heritage Site. According to UNESCO, the definition of the historic urban landscape (HUL) emphasizes the interdependence between cultural heritage, the natural environment, and the evolution of urban life. However, underwater, the Seine River abounds of microscopic life constituted by phytoplankton organisms that are essential to aquatic ecosystems. Revealing this invisible life can help raise public awareness of the importance of the living as a natural heritage – similar to cultural heritage. The HUL approach should recognize the value of these autotrophic (self-feeding) microorganisms and the ecosystem services they provide. Several activities within a citizen science project offer the possibility to raise public awareness through plankton observation workshops. This approach also engages citizens in the protection of natural heritage for future generations.

Citizen science projects produce copious amounts of data; however, if not properly managed, the data could be lost or underused. A knowledge management framework and quantitative research design were employed, where primary data were collected through an online questionnaire from academic librarians. The study found that good data management practices are lacking in academic libraries, leading to noncompliance with FAIR data principles. The study significantly contributes to the enhancements in academic libraries’ policies and guiding documents to view citizen science data as knowledge assets to be retained and reused to avoid reinventing the wheel.

Repeat photography offers a simple but effective method for visualising changes in the landscape and can be employed in participatory scientific projects. It is used in geosciences and ecology to analyse long-term developments, in exhibitions and citizen science projects to raise awareness, and in transdisciplinary processes to open up new avenues for dialogue on sustainability and land use.

Urban community gardens are collectively managed (agro)ecosystems shaped by diverse gardening practices that influence both planned and associated biodiversity. Yet, biodiversity-mediated ecosystem services in these gardens remain underexplored, and gardeners are rarely engaged as collaborators in scientific research. In this study, we investigated how bee diversity and urbanization factors affect pollination services, measured by the fruit set of common garden crops under real-world gardening conditions. Additionally, we examined participation dynamics within our citizen science approach and explored their relationship with the collected data as well as participants-reported challenges such as poor plant health. We collaborated with 73 gardeners in 22 gardens in Berlin and Munich, Germany, to measure the fruit set of 150 crops, mainly from the families Cucurbitaceae and Solanaceae. In parallel, researchers conducted systematic bee observations and quantified urbanization factors such as air temperature and surrounding imperviousness. We found a significant positive interaction between bee species richness and landscape imperviousness for the fruit set of Cucurbitaceae, emphasizing the importance of species-rich bee communities for pollination services in urban gardens. In contrast, no significant environmental predictors explained the fruit set of the Solanaceae group. Instead, we found that differences in sampling frequency led to significant differences in fruit set measurements, suggesting that self-pollination or an observer bias may contribute to variability. Participation types (differing in duration and frequency of data collection) were not affected by plant health issues or difficulties with the protocol, indicating that participant engagement in this real-world citizen science project was robust to practical challenges. Our findings highlight the potential of diverse bee communities to mitigate negative effects of urbanization on crop productivity in urban community gardens and demonstrate the value of citizen science for pollination research. Future citizen science approaches should balance scientific accuracy with participant autonomy, for instance, by coordinating crop selection or fostering a systematic recording of management practices. Key lessons learned include involving target groups early in project design and ensuring clear communication of data quality standards.

ABSTRACT Information technology facilitates participation in various scientific tasks in the online communities of citizen science (CS) projects. Previous research suggests that the production of scientific knowledge is more robust when participants are engaged not only in the scientific activities of data collection, but also in data analysis. However, only few participants engage in data analysis. Although their motivation and attitudes might influence participants’ engagement, little is known about how motivation and attitudes are related to engagement in different scientific activities. Using latent profiles of engagement and multinomial logistic regression analysis of motivation and attitudes, we show that the influence of motivation and attitudes differs between the activities of data collection and data analysis. Intrinsic motivation and positive attitudes promoted active engagement in data collection, but had opposite effects in data analysis. These findings suggest that citizens’ engagement levels and the driving factors vary between different scientific activities. Implications highlight the need for different support strategies to enhance citizen participation in full scientific processes, and point to potential structural adjustments in CS project designs. This research underscores the importance of tailored motivational and support mechanisms to enhance citizen engagement in data analysis for better learning and a more robust knowledge production.

Abstract Overlapping galaxies, in which a foreground galaxy partially overlaps a background galaxy, offer a unique opportunity to measure dust attenuation, a key nuisance parameter in galaxy studies, empirically and in great detail by modelling the light of both the foreground and background galaxy and inferring the missing light in the overlapping region. However, the current catalogue of overlapping pairs is relatively limited in number compared to catalogues dedicated to individual galaxies. Expanding this catalogue is not only a necessity to facilitate further detailed dust studies beyond the few limited studies conducted thus far, but also to improve pair-to-pair variance and support automated identification through machine learning techniques. To achieve this, we utilise galaxies classified as “overlapping” from Galaxy Zoo DECaLS (GZD-1, -2, and -5), along with images from Data Release 10 (DR10) of the DESI Legacy Survey, in our individual citizen science project to classify these pairs directly using volunteers. This new catalogue will not only provide a wealth of targets for future dust studies but will also contribute to a deeper understanding of these pairs and dust as a whole.