Research & reports

Felderhoff J. · Ecological Applications · Germany (Berlin)

Documented 26 genera and 102 bee species across 18 Berlin community gardens, finding that higher plant species richness and greater deadwood amounts increased wild bee species number and functional diversity.

Herrmann J., Buchholz S., Theodorou P. · Scientific Reports · Germany

In German urban dry grasslands, examined effects of local habitat quality, urbanisation (impervious surfaces), and 3D connectivity on flower visitors; bee and butterfly species richness declined with increasing impervious surface.

Nguyen H., Schmack J., Egerer M. · Basic and Applied Ecology · Germany (Munich)

Conducted a pollination-exclusion experiment with two cultivated and two wild plant species across 13 Munich community gardens, finding cultivated-plant fruit and seed mass positively correlated with temperature and pollinator diversity.

Rossi Rotondi B. · Urban Ecosystems · Cordoba, Argentina

Surveying bees and blooms across 13 gardens in Cordoba, Argentina, the study found floral species evenness to be the strongest driver of bee abundance, diversity and functional trait diversity.

Gail MacInnis, Etienne Normandin, Carly D. Ziter · PeerJ · Canada (Montreal)

A study of wild bee communities across Montreal, Canada, greenspaces with differing honey bee densities, surveyed in 2020 and compared with 2013 baseline data. Sites with more honey bees had fewer wild bee species, and the negative association was strongest for small-bodied bees (inter-tegular span under 2.25 mm), whose shorter foraging ranges limit their access to floral resources under competition. Urban beekeeping is commonly promoted as environmentally beneficial, but this observational evidence indicates that high-density operations may pressure native pollinators through resource competition and pathogen transmission; the design is correlational rather than an experimental test of causation.

Sarah E. Orr · American Entomologist · United States

Community gardens are presented as a solution to food insecurity and a means to promote native bee conservation. They provide local fresh produce, affordable nutritious options, and foster education in gardening and nutrition. Additionally, community gardens support biodiversity, as roughly 35% of human food crops depend on animal pollination, with bees being primary pollinators for many crops.

María José Ludewig, Patricia Landaverde‐González, Klaus‐Peter Götz, Frank‐M. Chmielewski · Journal of Insect Conservation · Global

This study assessed bee visits to experimental blueberry and cherry orchards in an urban landscape to understand how air temperature affects the pollination contribution of honey bees and wild bees. Bumble bees and honey bees were the most important floral visitors, followed by Anthophora plumipes. Honey bees' potential contribution to pollination services decreased with air temperature changes, but this was offset by the niche complementarity of bumble bees.

Elda Míriam Aldasoro Maya, Ulises Rodríguez‐Robles, María Luisa Martínez Gutiérrez, Guelmy Anilú Chan Mutul, Teresita Avilez López, Helda Morales, Bruce G. Ferguson, Jorge Mérida‐Rivas · Frontiers in Sustainable Food Systems · Mexico (Tabasco)

Meliponiculture, or stingless bee breeding, in Mesoamerica serves as an effective tool for agroecological education, scaling, and pollinator conservation. In Tabasco, Mexico, activities included documenting contemporary knowledges, community agroecological workshops, guided visits to an institutional meliponary, and promoting school gardens, utilizing "knowledge dialogues" as a methodological approach. The study identified characteristics of stingless bees and their cultivation, such as their ecological and cultural importance, role as pollinators, association with community values, and productive potential, making them excellent mediators for biocultural conservation and agroecological education.

Myung‐Bok Lee · PeerJ · China

This study investigated how environmental features within and surrounding urban farmlands affected the abundance of Asian honey bees (Apis cerana) and cabbage white butterflies (Pieris rapae) in a megacity of China during winters. P. rapae abundance increased with local crop diversity but was strongly negatively associated with landscape-scale crop and weed covers. A. cerana responded positively to fine-scale flower cover, increased with local-scale weed cover, but decreased with increasing landscape-scale weed cover.

Lisandra Hernández-Guanche, Yoerlandy Santana Baños, Yusniel Dago-Dueñas, Ramón Hernández Carballo, Armando Del Busto-Concepción · Revista Mexicana de Ciencias Agrícolas · Cuba

This study identified the beneficial entomofauna associated with arboreal species in urban agriculture settings in Pinar del Río, Cuba. Between September 2019 and March 2020, a floristic inventory of arboreal biodiversity was conducted, and samples of bioregulators were collected. Twenty-three arboreal species were inventoried, with 65% being fruit trees. The highest species richness was detected in the orders Diptera, Mesostigmata, Hymenoptera, and Araneae. The most frequent bioregulators were Condylostylus sp., Ocyptamus costatus, and Phytoseiulus sp., while the arboreal species with the highest proportion of associated arthropods were Persea americana, Citrus limon, Morinda citrifolia, and Psidium guajava.

Shivant Jhagroe · Urban Studies · Netherlands

A study of the Gandhi-garden, a community garden in Rotterdam, the Netherlands, that is part of the global Transition Towns movement, drawing on participatory ethnography, interviews, and online documents. Challenging the anthropocentrism common in research on urban sustainability and resilience, the paper analyses everyday acts such as weeding and permacultural planting as "more-than-human assemblage" place-making practices involving insects, plants, soil, and fences that challenge urban neoliberalism. It also examines expressions of solidarity with Palestine through olive trees and non-violence thinking, alongside tensions between humans and non-humans over dog waste and birds that take harvested produce.

Emanuela Granata, Paolo Pedrini, Luigi Marchesi, Chiara Fedrigotti, Paolo Biella, Silvia Ronchi, Mattia Brambilla · Agriculture Ecosystems & Environment · Italy

This study investigated the environmental and management factors influencing bird communities, pollinating insects, and two ecosystem services — pollination and nature-based recreation — along an urban-natural gradient dominated by agricultural areas (vineyards, apple orchards, and grasslands) in northern Italy. Flower-visiting insects were mainly affected by management and environmental-climatic variables, with flowers at field margins and within vineyard and apple-orchard inter-rows best predicting pollinator and flower-visiting-insect abundance; sward height and grassland cover promoted insect abundance, while vineyards and apple orchards had a negative effect on it. Bird communities were mainly shaped by land-use/land-cover and management variables, with landscape heterogeneity and linear elements having a major positive effect; apple orchards negatively affected the richness and abundance of most bird species, and vineyards negatively affected overall bird abundance, while hedgerows had a positive effect on richness. Nature-based recreation was greater in areas with low or intermediate vineyard or urban cover, with apple orchards and intensively managed grasslands having negative effects and waterways a positive effect. The study concludes that apple orchards and large vineyards are largely unsuitable for biodiversity and ecosystem services.

Michael Hardman, Katherine C. R. Baldock, Stuart Connop, Kenny Taylor, Ross Stirling · · Global

Against a backdrop of high interest in blue-green infrastructure (BGI), this chapter examines how developers, planners, engineers, architects, and other actors are incorporating BGI into urban and rural environments. It notes that evidence shows approaches are often basic, relying on traditional landscaping methods that fail to explore BGI's possibilities, and reflects on advances in more radical approaches. The chapter begins with a review of how pollinator biodiversity can be enhanced through innovative BGI systems, then addresses incorporating food growing into BGI strategies and co-benefits with low-carbon energy.

Martin Šlachta, Tomáš Erban, Alena Votavová, Daniela Tomešová, Marta Václavíková, Taťána Halešová, Elena Shcherbachenko, Tomáš Bešta, Magda Edwards‐Jonášová, Renata Včeláková, Vladana Procházková, Pavel Cudlín · Journal of Apicultural Research · Europe

This study investigated pesticide contamination using larval food provisions (a mix of pollen and nectar) of mason bees (Osmia spp.) nesting in artificial shelters at twelve allotment garden sites in Prague and Brno, with seven commercial croplands (fruit orchards, oilseed rape fields) selected for comparison. In total, 79 samples of larval provisions were analyzed using a validated UPLC-MS/MS method covering 262 pesticides and related metabolites. Fifty-six pesticide residues were detected in the allotments and 74 in cropland sites, with 50 compounds common to both; fewer residues were found in allotments (mean 14.3±0.9) than in croplands (21.5±1.1; df=17.4, t=-2.9), though some residues exceeded 10 ppb. The highest levels were observed for the fungicide pyrimethanil (mean 1,989 ppb, maximum 3,983 ppb) and, among insecticides, thiacloprid (mean 136 ppb, maximum 170 ppb). The results supported the view of a lower risk of pesticide exposure in urban allotment gardens than in croplands, though given limited knowledge of sublethal effects of pesticides, and especially pesticide mixtures, on solitary bee development, the study recommends regulation or control of pesticide use in allotment gardens.

Tina McIntyre, Hamutahl Cohen, Rachel Gutner, Tiare Saracino, Esen Momol · EDIS · United States (Florida)

This is a five-page extension publication from the UF/IFAS Environmental Horticulture Department that provides a decision tree to help edible-landscape gardeners decide how to respond to wildlife in their growing areas. It states that while wild animals can damage crops, this need not require conflict, and aims to help gardeners become more accepting of wildlife species present in their managed area and coexist with them.

Elsa Blareau, Pauline Sy, Karim Daoud, Fabrice Réquier · Insects · France

A study near Paris, France, evaluated the effects of insect-mediated pollination service and potential pollination deficit on fruit set, seed set, and fruit quality (size, weight, malformation) in strawberries (Fragaria × ananassa) growing in an urban area, using flower-visitor observations and pollination experiments. Flower-visitor observations found that the pollinator community consisted solely of unmanaged (wild) pollinators, despite beehives being present in the surrounding landscape. Pollination experiments showed that wild-insect pollination improved fruit size as a qualitative measure of production but did not improve fruit set, and no evidence of pollination deficit was found in this urban environment.

Julia M. Schmack, Monika Egerer · Urban Ecosystems · Germany

A study in 30 urban community gardens in Berlin and Munich, Germany, observed 20 focal plant species and 13 common bee and non-bee flower visitor groups, examining how landscape urbanization and the availability of floral and nesting resources within gardens affected the complexity (nestedness, linkage density, connectance) of pollinator interaction networks. Dominant flower visitors changed over the growing season, with non-bee visitors such as ants and flies dominant early in the season and bees becoming important later. Nestedness of the flower visitor network increased with floral richness within gardens, while floral abundance, the impervious surface surrounding gardens, garden size, and nesting resource availability did not strongly influence the networks. The findings indicate that high floral richness in community gardens can ensure the complexity and stability of flower visitor networks, that non-bee visitors play an important role especially in the shoulder seasons, and that urban gardeners play a key role in mediating flower visitor interactions through their gardening practices.

Tainan Messina, Rui Figueira, José M.L. Santos · Ecosystem Services · Europe

A study in intensive farming systems of Central Portugal developed a methodology integrating species, trait and crop data, pest predation indicators and local farmers' expertise to estimate pest consumption by birds. Using point count data and each species' energy requirements and life-cycle characteristics, it estimated birds' daily invertebrate consumption and examined the relationship between birds and service provision along a tree gradient. Relating habitat requirements to pest control services via species guilds, the study found higher predation in annual crops close to trees or woody vegetation than in crop-only plots. After analyzing the methodology's main challenges and strengths, the study concludes that farmers' participation improved the accuracy and results of the analysis and that the methodology's holistic character can guide stakeholders and policymaking more effectively.

Mary Leou, Tania Goicoechea, Bethany Kogut · Catholic education/Catholic education (Dayton, Ohio. Online) · United States (New York City)

A report on "Bees Alive!", a civic ecology program run over three years by the NYU Wallerstein Collaborative for Urban Environmental Education & Sustainability in Greenpoint, Brooklyn, New York. A university, public schools, non-profit organizations and the Lentol Garden community garden collaborated to establish a native-plant pollinator garden, funded by EPA Region 2, using place-based education and experiential learning theory to create an outdoor classroom that supports wildlife and teaches the public about pollinators.

Jean Pascal · Biodiversity online journal. · Global

Noting that insects constitute most of the biodiversity on Earth and provide a wide range of services to society while being threatened by human activities such as habitat destruction and urbanization, this article assesses advances in understanding the impact of insects on sustainable food production in low-income countries. It focuses on two research topics that have emerged in recent years: entomophagy combined with the creation of small household farms rearing insects for sale (the Thai example), and the use of insects to improve soil fertility and nutrient availability (the Zai example). The article advocates considering the diversity of solutions and adaptations found in nature, arguing that the ways local communities and ethnic groups use natural resources are vast and should be seen as a source of inspiration for scientists developing sustainable food systems.

Lawrence D. Harder, Ronald M. Miksha · Oecologia · Germany (Munich)

A re-analysis of the observations behind Renner et al. (2021), which had concluded that an increase in managed honey bee hives between 2019 and 2020 intensified competition with non-Apis bees in the Munich Botanic Garden, Germany. The comment shows that the change in hive numbers did not statistically alter honey bee visitation to 29 plant species either within or between years, so the shift in the proportion of non-Apis bees among visitors is better explained as a response to reduced overall floral resource availability in 2020. The claim that urban beekeeping suppresses native pollinators is therefore supported by some observational studies and contested by re-analyses that find the statistical basis insufficient.

Joan Casanelles‐Abella, Simone Fontana, Bertrand Fournier, David Frey, Marco Moretti · Ecological Applications · Switzerland (Zurich)

This study in 23 urban gardens in Zurich, Switzerland, examined feeding niche partitioning between wild bees and honeybees. Researchers found that feeding niche partitioning increased with wild bee species richness and in sites with lower landscape-scale resource availability, which also had lower honeybee abundances. However, beekeeping intensity at local and landscape scales did not directly influence community feeding niche partitioning or wild bee species richness, suggesting direct competition for resources was not a main driver for the wild bee community.

Alan Dorin, Tim Taylor, Adrian G. Dyer · PLOS Sustainability and Transformation · Global

This study used an agent-based model to explore the impact of insect flower constancy, heterospecific pollen transfer, and crop patch size on pollination in urban farms. It found that highly constant pollinators were most effective in the smallest patches, while less constant insects performed better in intermediate-sized areas. The model identified an optimal "Goldilocks zone" for pollination around 11m x 11m, suggesting that collaborative management to increase single-crop patch size could improve pollination in community farms.

Amelie M. Vanderstock, Cecilia Grandi-Nagashiro, Gaku Kudo, Tanya Latty, Shoko Nakamura, Thomas E. White, Masashi Soga · Journal of Insect Conservation · Japan

An online survey was conducted with 443 adults in Japan to investigate the association between nature and gardening experiences, demographics, species identification knowledge, and biophilia (liking) and biophobia (dislike, fear, and disgust) towards invertebrates. Frequent gardeners were found to be more likely to express biophilia and perceive invertebrates as beneficial, and generally less likely to express biophobia. The results suggest that gardening can serve as a pathway to foster appreciation for invertebrate biodiversity in urban settings.

Jorge Godoy Román · Materia Arquitectura · Germany (Berlin)

This interview with Erika Mayr, an entomologist, horticulturist, ecologist, beekeeper, gardener, writer, and caretaker, explores her over 25-year dedication to understanding the importance of bees for other species. It highlights her personal relationship with bees, particularly in Berlin's urban environment, which involved various urban spaces and communities. Now based in Rome, Mayr shares her experiences and current projects in the city.