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Bees are crucial for food security and biodiversity. However, managed bees are increasingly considered drivers of wild bee declines, leading to stakeholder conflicts and restrictive policies. We propose avenues to reconcile wild and managed bee proponents and point out knowledge gaps that hinder the development of evidence-based policies., Competing Interests: Declaration of interests The authors have no interests to declare., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Many invertebrates exhibit parental care, posited as a precursor to sociality. For example, solitary foundresses of the facultative social orchid bee Euglossa viridissima guard their brood for 6+ weeks before offspring emerge, when the nest may become social. Guarding comes at the fitness cost of foregoing the production of additional offspring. Yet it is unclear whether guarding (extended maternal care) can enhance offspring survival such that it outweighs those fitness costs, or if it is a consequence of the selective benefits of sociality, including extended female longevity. Experimental removal of solitary foundresses from nests of E. viridissima revealed an immediate fitness loss: decreased offspring survival. A mathematical model exploring the trade-off between extended maternal care versus non-guarding revealed that extended maternal care is immediately advantageous to a solitary mother if nest establishment takes longer than a threshold 1.7-12.5 days. Below this threshold, our model suggests that social fitness gains (acquiring helper daughters) need to be invoked to explain the evolution of extended maternal care. Enhanced survival of offspring through guarding and nest inheritance may nevertheless ease conditions for the evolution of sociality by favouring extended adult longevity and brood care in incipient social species like E. viridissima .

Man-made agricultural stressors have been identified to compromise the reproductive dynamics of bee populations within agricultural environments. With the aid of bee hotels, we explored the influence of conventional and organic farming systems on local population size and body traits of the mason bee, Osmia bicornis, in southern Germany. We further used a chemical ecology approach and bioassays to test whether farming management influence male pre-copulatory behaviors. We observed a positive relationship between the extent of organic agriculture in the landscape and both overall brood cell production and nesting frequency. Moreover, farming systems were found to influence body traits, with bees from organic sites being smaller in size and having a different cuticular hydrocarbon composition compared with those at conventional sites. Bioassays revealed that males were more sexually attracted to freeze-killed females from conventional sites compared with those from organic sites. Intriguingly, treating females from organic fields with synthetic semiochemicals enhanced their sexual attraction to levels comparable with females from conventional sites. Our findings shed light on the intricate interplay between farming practices and the reproductive behaviors of wild mason bees, emphasizing the need for a comprehensive understanding of these dynamics for effective conservation and management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The aboveground oligolectic bee, Heriades truncorum, is a particularly good model for studying the impact of pesticides on sexual communication, since some aspects of its mating behavior have previously been described. We have tested (1) the interference of the pesticide flupyradifurone on male precopulatory behavior and male mating partner preferences, (2) the way that the pesticide interferes in male quality assessment by the female, and (3) the effects of the pesticide on the chemical compounds in the female cuticle. We exposed bees of both sexes to a sublethal concentration of flupyradifurone. Various behaviors were registered in a mating arena with two females (one unexposed and one exposed) and one male (either unexposed or exposed). Unexposed males were quicker to attempt to mate. Treatment also impacted precopulatory behavior and male quality assessment by females. Males approached unexposed females more quickly than insecticide-exposed ones. Females exposed to insecticide produced lower amounts of some cuticular hydrocarbons (sex pheromone candidates) and appeared less choosy than unexposed females. Our findings suggest that insecticide exposure affects sexual communication, playing a role both in male preference and in male quality assessment by the female., (© 2023 The Authors. Insect Science published by John Wiley & Sons Australia, Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.)

Solitary bees are among the most important pollinators worldwide however population declines especially in croplands has been noticed. The novel pesticide sulfoxaflor is a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects. While there is evidence of a negative impact of neonicotinoids on bees of several social organization levels, our overall knowledge on the impact of sulfoxaflor on bees is poor. Here we present for the first time a study showing effects of field realistic doses of sulfoxaflor on solitary bees. Bees submitted to long term exposure of field realistic doses of sulfoxaflor (5 µg dm -3 , 10 µg dm -3 , 50 µg dm -3 ) and control were observed regarding their survival rate. Moreover, we recorded metrics related to flower visitation and flight performance. We discover that the highest field realistic dose is lethal to Osmia bicornis along five days of exposure. The effect of sulfoxaflor reduces the outcome of foraging, important features for fruit and seed production of cross-pollinated plant species. Bees exposed to pesticide visited flowers mostly walking rather than flying. Flight performance was also impaired by the pesticide., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

The flowers of plants of the genus Ludwigia are an important source of food for several species of bees. In the current study, we conducted an experiment with the aim to describe the reproductive biology and phenology of L. nervosa ; to identify the species of visiting bees; analyze the foraging behavior of bees; and to investigate whether the reproductive success of the species is related to the foraging activity of bees. We found that the flowers received visits from several native bee species (n = 7), in addition of the exotic honey bees which came to be the dominant species. During visits the majority of the bees foraged in both resources, pollen and nectar. The significantly higher production of fruits in open pollinated pollination experiment compared to artificial cross pollination, suggests honey bees as effective pollinator of this plant species in the study site. Pollen deposition occurs efficiently, given the absence of pollen limitation. Despite massive visitation of honey bees, Ludwigia nervosa is attractive to native bees, and therefore it may help to sustain population of both native and exotic pollinators in fragmented humid areas.

Environmental quality (e.g., diversity of resource availability, nesting sites, environmental display) plays an important role in an animal's life. While homogeneous environments can restrict organisms from developing activities such as food seeking (behavioral impairment), more complex environments allow animals to perform activities with learning and behavioral perfecting outcomes. Pesticides are known to affect the learning and foraging behaviors of bees; however, little is known about the counterbalance displayed by the environment. Herein, we conducted two experiments that simulated distinct environmental displays, in which the effects of a fungicide (Indar TM 5EW-febunconazole) on solitary bee foraging activities were tested. We found that the fungicide only impaired the activities of bees in one of the studied environments. The difference in visitation rates and flower exploitation of bees between the two different environmental displays led to changes in metrics of bee-flower networks across environments. Linkage density, a metric associated with pollination efficiency that is known to be impacted by different environments, differed across environments. Our results showed that ecological interaction network metrics can differ regarding the different environmental displays. This study indicates that environmental complexity helps balance the negative effects of pesticides on solitary bees and highlights the potential use of solitary bees as model organisms for experimental simulations of environmental change.

Life-sciences are pointing towards an alarming worldwide pollinator decline. This decline proceeds along with overall biodiversity losses, even in the context of urban landscapes and human welfare. At the same time, social-sciences are arguing an increased distance from nature, experienced by citizens. The strong connection between the public good and pollinator sustainability, even in urban areas, is well-documented. However, usually basic and applied life-sciences tend to underestimate public perception of nature, which is better tackled by the fields of social-sciences. Therefore, more efforts are needed to link scientific questions and public 'perception' of nature. We designed a transversal project where research questions directly confront public concerns: i.e., even while addressing scientific knowledge gaps, our questions directly arise from public concerns. Social studies highlighted that appreciation of (exotic) plants is related to the impact they may have on the surrounding natural environment: therefore, we investigated links of native and exotic flowers to local pollinators. Other studies highlighted that scientific results need to link to everyday individual experience: therefore, we investigated pollination modes of the renown Salvia, native and exotic, largely used in cuisine and gardening. The botanic garden was the promoter of scientific questions addressed by the public, and also collated the results in a travelling exhibition. The exhibition, together with a dedicated catalogue, were especially designed to enlighten the wide public on the relationships that plants, native and exotic alike, establish with the surrounding world., Competing Interests: The authors have declared that no competing interests exist.

Throughout evolutionary history bees have developed complex communication systems. For social bees, communication is important for both the individual and the development of the colony. Successful communication helps bees to recognize relatives, defend the colony, and promote recruitment to optimize foraging of floral resources. Bees' contribution to pollination is of broad environmental and economic importance. However, studies have reported that anthropogenic actions, such as the use of pesticides, negatively affect bee survival and behavior. We tested the effect of a commercially available pesticide mix containing two pesticide classes, a neonicotinoid and a pyrethroid, on the social behavior of the stingless bee, Melipona quadrifasciata (Lepeletier, 1863). After determining a sublethal dose of the pesticides, we tested the effect of an acute dose on antennation and trophallaxis behaviors of worker bees. Our results showed a drastic reduction in the communication and social interactions of bees., (Copyright © 2018 Elsevier Inc. All rights reserved.)