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Bumble bees are the primary commercial pollinators for greenhouse‐grown crops and managing them requires insight into the Bombus life cycle. However, some aspects of the life cycle are not fully understood. Once mated, adult Bombus gynes can be stored for a short term at a constant low temperature (CLT). However, survival rates for some species are low during CLT, particularly when storage periods exceed a month. To address this, we tested the hypothesis that Bombus gynes stored in a fluctuating thermal regime (FTR) have increased survival compared to gynes stored in CLT. Specifically, the FTR had a baseline temperature of 2°C, with a daily fluctuation to 20°C relative to the CLT of 2°C with no warming pulse. We tested the effects of FTR on gyne survival and post‐cold storage lipid content in three species used for commercial pollination in North America: B. vosnesenskii, B. huntii and B. impatiens. We further assessed how additional factors influence cold storage survival, including gyne body weight, body size and colony age. Survival responses varied among species. Bombus vosnesenskii and B. huntii had a lower survival rate in FTR compared to CLT, but B. impatiens gynes had a significantly higher survival rate in FTR. We did not observe significant effects of FTR on lipid stores for any species, but survival increased with an increasing initial weight prior to cold storage. Moreover, gynes produced later in the colony life cycle had lower body weight and decreased survival compared to early emerging gynes. Our study provides insight into how cold storage conditions interact with colony and gyne characteristics to influence captive overwintering survival. Our findings have economic applications for improving commercial rearing and efforts for conservation rearing of at‐risk Bombus species. [ABSTRACT FROM AUTHOR]

Bumblebees are important pollinators in agricultural ecosystems, but their abundance is declining globally. There is an urgent need to protect bumblebee health and their pollination services. Bumblebees possess specialized gut microbiota with potential to be used as probiotics to help defend at‐risk bumblebee populations. However, evidence for probiotic benefits on bumblebees is lacking. Here, we evaluated how supplementation with Lactobacillus melliventris isolated from bumblebee gut affected the colony development of Bombus terrestris. This native strain colonized robustly and persisted long‐term in bumblebees, leading to a significantly higher quality of offspring. Subsequently, the tyrosine pathway was upregulated in the brain and fat body, while the Wnt and mTOR pathways of the gut were downregulated. Notably, the field experiment in the greenhouse revealed the supplementation of L. melliventris led to a 2.5‐fold increase in the bumblebee survival rate and a more than 10% increase in the number of flowers visited, indicating a better health condition and pollination ability in field conditions. Our study represents a first screening for the potential use of the native gut member, L. melliventris, as probiotic strains in hive supplement for bumblebee breeding, which may be a practical approach to improve immunity and hive health. [ABSTRACT FROM AUTHOR]

Agricultural intensification has been identified as one of the key causes of global insect biodiversity losses. These losses have been further linked to the widespread use of agrochemicals associated with modern agricultural practices. Many of these chemicals are known to have negative sublethal effects on commercial pollinators, such as managed honeybees and bumblebees, but less is known about the impacts on wild bees. Laboratory‐based studies with commercial pollinators have consistently shown that pesticide exposure can impact bee behavior, with cascading effects on foraging performance, reproductive success, and pollination services. However, these studies typically assess only one chemical, neglecting the complexity of real‐world exposure to multiple agrochemicals and other stressors. In the summer of 2020, we collected wild‐foraging workers of the common eastern bumblebee, Bombus impatiens, from five squash (Cucurbita) agricultural sites (organic and conventional farms), selected to represent a range of agrochemical, including neonicotinoid insecticide, use. For each bee, we measured two behaviors relevant to foraging success and previously shown to be impacted by pesticide exposure: sucrose responsiveness and locomotor activity. Following behavioral testing, we used liquid chromatography–tandem mass spectrometry (LC–MS/MS) chemical analysis to detect and quantify the presence of 92 agrochemicals in each bumblebee. Bees collected from our sites did not vary in pesticide exposure as expected. While we found a limited occurrence of neonicotinoids, two fungicides (azoxystrobin and difenoconazole) were detected at all sites, and the pesticide synergist piperonyl butoxide (PBO) was present in all 123 bees. We found that bumblebees that contained higher levels of PBO were less active, and this effect was stronger for larger bumblebee workers. While PBO is unlikely to be the direct cause of the reduction in bee activity, it could be an indicator of exposure to pyrethroids and/or other insecticides that we were unable to directly quantify, but which PBO is frequently tank‐mixed with during pesticide applications on crops. We did not find a relationship between agrochemical exposure and bumblebee sucrose responsiveness. To our knowledge, this is the first evidence of a sublethal behavioral impact of agrochemical exposure on wild‐foraging bees. [ABSTRACT FROM AUTHOR]

In a time of increasing threats to bumble bees (Hymenoptera: Apidae: Bombus), it is important to understand their ecology and distribution. As experts are limited in resources to conduct field surveys, there is potential for community scientists to help. The Bumble Bee Watch (BBW) community science program involves volunteers taking photos of bumble bees in Canada and the USA and submitting them, along with geographic and optional plant information, to a website or through an app. Taxon experts then verify the bee species identification. The Bumble Bees of North America database (BBNA) stores data (no photographs) collected and identified by more traditional scientific methods over the same range. Here we compared BBW data to BBNA data over all years and just 2010–2020 to understand the scientific contribution of community scientists to the state of the knowledge about native bumble bees. We found that BBW had similar geographic and species coverage as BBNA. It had records from all 63 provinces, states, and territories where bumble bees occur (including four more than BBNA in 2010–2020), and represented 41 of the 48 species in BBNA (with ten more species than BBNA in 2010–2020). While BBW contributed only 8.50% of records overall, it contributed 25.06% of all records over 2010–2020. BBW confirmed the persistence of species and identified new locations of species, both inside and outside of the previously known extent of occurrences. BBW also contributed a wealth of ecological information, such as unique plant genera and species data for almost all the bee species. Thus, while BBW had fewer bee records than the BBNA database overall, it helped to fill in data gaps and provided novel information, complementing the traditional methods. This community science program is valuable in helping to inform conservation management for bumble bee species. [ABSTRACT FROM AUTHOR]

Mitochondria are intracellular organelles responsible for cellular respiration with one of their major roles in the production of energy in the form of ATP. Activities with increased energetic demand are especially dependent on efficient ATP production, hence sufficient mitochondrial function is fundamental. In bees, flight muscle and the brain have particularly high densities of mitochondria to facilitate the substantial ATP production required for flight activity and neuronal signalling. Neonicotinoids are systemic synthetic insecticides that are widely utilised against crop herbivores but have been reported to cause, by unknown mechanisms, mitochondrial dysfunction, decreasing cognitive function and flight activity among pollinating bees. Here we explore, using high-resolution respirometry, how the neonicotinoid imidacloprid may affect oxidative phosphorylation in the brain and flight muscle of the buff-tailed bumblebee, Bombus terrestris. We find that acute exposure increases routine oxygen consumption in the flight muscle of worker bees. This provides a candidate explanation for prior reports of early declines in flight activity following acute exposure. We further find that imidacloprid increases the maximum electron transport capacity in the brain, with a trend towards increased overall oxygen consumption. However, intra-individual variability is high, limiting the extent to which apparent effects of imidacloprid on brain mitochondria are shown conclusively. Overall, our results highlight the necessity to examine tissue-specific effects of imidacloprid on respiration and energy production. [ABSTRACT FROM AUTHOR]

Patterns of abundance across space and time, and intraspecific variation in body size, are two species attributes known to influence diet breadth and the structure of interaction networks. Yet, the relative influence of these attributes on diet breadth is often assumed to be equal among taxonomic groups, and the relationship between intraspecific variation in body size on interaction patterns is frequently neglected. We observed bee–flower interactions in multiple locations across Montana, USA, for two growing seasons and measured spatial and temporal patterns of abundance, along with interspecific and intraspecific variation in body size for prevalent species. We predicted that the association between spatial and temporal patterns of abundance and intraspecific variation in body size, and diet breadth, would be stronger for bumble bee compared to non-bumble bee species, because species with flexible diets and long activity periods can interact with more food items. Bumble bees had higher local abundance, occurred in many local communities, more intraspecific variation in body size, and longer phenophases compared to non-bumble bee species, but only local abundance and phenophase duration had a stronger positive association with the diet breadth of bumble bee compared to non-bumble bee species. Communities with a higher proportion of bumble bees also had higher intraspecific variation in body size at the network-level, and network-level intraspecific variation in body size was positively correlated with diet generalization. Our findings highlight that the association between species attributes and diet breadth changes depending on the taxonomic group, with implications for the structure of interaction networks. [ABSTRACT FROM AUTHOR]

Floral features, the pollination process, the breeding system, and fruiting success are documented in the Andean terrestrial orchid Gomphichis valida. Studies were performed at the Department of Ancash, Peru, at ca. 4250 m a.s.l., from June to November 2022. The breeding system was studied through controlled pollinations in plants excluded from pollinators (bagged). Natural pollination was studied in the field and through photos and videos. The flowers are nectariferous and non‐protandrous and present the longest lifespan reported so far for a neotropical terrestrial orchid (53–80 days). This species is pollinator dependent (unable to set fruit and seed without the agency of pollinators) and self‐compatible. The observed pollinators belong to three functional groups that appeared successively (in order of appearance): hummingbirds (Chalcostigma stanleyi), bumblebees (Bombus coccineus and Bombus rubicundus), and solitary Halictidae bees (Augochlorella sp.). All recorded pollinators probe the flowers for nectar. The pollinaria adhere to the bee mouthparts and onto the lateral side of the hummingbird bill. Bumblebees were the most frequent and efficient functional group (up to 62.07% of the observed pollination events), followed by Halictidae (31.03%) and hummingbirds (6.90%). Natural fruiting success is high (66.66%–94.49%). Such high natural fruiting success is unexpected at high altitudes, but it is likely explained by a combination of factors, including the long floral lifespan, nectar secretion, and self‐compatibility. This is the first report of hummingbirds as pollinators of Cranichidinae orchids, and G. valida is, to the best of our knowledge, a neotropical orchidoid orchid with the most generalist pollination biology recorded so far. [ABSTRACT FROM AUTHOR]

The transmission of pathogens from reservoir to recipient host species, termed pathogen spillover, can profoundly impact plant, animal, and public health. However, why some pathogens lead to disease emergence in a novel species while others fail to establish or do not elicit disease is often poorly understood. There is strong evidence that deformed wing virus (DWV), an (+)ssRNA virus, spills over from its reservoir host, the honeybee Apis mellifera, into the bumblebee Bombus terrestris. However, the low impact of DWV on B. terrestris in laboratory experiments suggests host barriers to virus spread in this recipient host. To investigate potential host barriers, we followed the spread of DWV genotype B (DWV-B) through a host's body using RT-PCR after experimental transmission to bumblebees in comparison to honeybees. Inoculation was per os, mimicking food-borne transmission, or by injection into the bee's haemocoel, mimicking vector-based transmission. In honeybees, DWV-B was present in both honeybee faeces and haemolymph within 3 days of inoculation per os or by injection. In contrast, DWV-B was not detected in B. terrestris haemolymph after inoculation per os, suggesting a gut barrier that hinders DWV-B's spread through the body of a B. terrestris. DWV-B was, however, detected in B. terrestris faeces after injection and feeding, albeit at a lower abundance than that observed for A. mellifera, suggesting that B. terrestris sheds less DWV-B than A. mellifera in faeces when infected. Barriers to viral spread in B. terrestris following oral infection may limit DWV's impact on this spillover host and reduce its contribution to the community epidemiology of DWV. [ABSTRACT FROM AUTHOR]

Insect pollination is an important process in the natural ecosystem and plays a vital role in crop reproduction. The bumblebee, Bombus terrestris (L.), is a widely used pollinator for crops, especially tomato. The efficiency of bee pollination is related to many factors, including biotic factors such as bee species, nutrition plants, and herbivores. Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) is one of the most common and serious pests of tomato plants. However, whether B. tabaci affects the pollination behaviour of B. terrestris on tomato, and how plant–herbivore–pollinator interactions are unclear. In this study, we found that B. terrestris preferred B. tabaci-damaged plants. Furthermore, plant volatiles of tomato plants damaged by B. tabaci were detected and analysed. Electroantennogram (EAG) and the Y-tube bioassay were used for olfactory responses of B. terrestris to plant volatiles. Interestingly, methyl hexanoate and eugenol induced by B. tabaci in tomato plants were found to significantly attract B. terrestris. Therefore, Bemisia tabaci influenced B. terrestris preference through volatiles. The plant volatile-mediated interaction between B. tabaci and B. terrestris could enrich our understanding of the interaction between herbivores and pollinators. In addition, methyl hexanoate and eugenol could be applied for synergist of pollination. [ABSTRACT FROM AUTHOR]

A rising global population will need more food, increasing demand for insect pollination services. However, general insect declines conflict with this demand. One way to mitigate this conflict is to grow crop flowers that are easier for insects to find and more rewarding to those that visit them. This study quantifies variation in the pollinator‐relevant traits of nectar and pollen production, flower size and flower shape in commercial strawberry, finding significant variation between varieties in all traits. Bumblebees could learn to distinguish between the extremes of variation in flower shape, but this learning is very slow, indicating that this variation is at the limit of that which can be detected by bumblebees. Bee preferences for nectar of differing sugar concentrations at field‐realistic volumes were consistent with previous observations at larger volumes, suggesting that it is valid to translate lab findings to the field. This study builds on our knowledge of the range of pollinator reward present in a single cultivated species and of the impact of field‐realistic levels of variation in floral traits on bumblebee preferences. [ABSTRACT FROM AUTHOR]

Bumblebees are important pollinators in both natural and agricultural ecosystems, but their survival and pollination service are threatened by extensive pesticide use. Due to regulation changes, acetamiprid has become the only neonicotinoid substance that can be used without restrictions and in open‐field cultivations in the European Union. Yet, we know little about how this active ingredient affects bumblebees' foraging behaviour and if such effects are similarly detrimental to those of other neonicotinoids. Here we investigated how a 14‐day‐long (chronic) exposure to low (5 ppb) and high (2500 ppb) concentrations of acetamiprid in syrup affected different aspects of foraging behaviour in buff‐tailed bumblebees (Bombus terrestris, Linnaeus). We recorded individual foraging at artificial food patches during one‐hour‐long trials and then compared several foraging‐related measures between differently dosed individuals. We found that 75.12% of the total syrup consumption occurred at the first‐exploited patch, but individuals did not exhibit any bias toward pesticide‐treated food patches. Chronic exposure to acetamiprid had little effect on individual foraging decisions at the first‐exploited food patch but significantly affected the time to the first feeding and the number of feedings at the second‐exploited patch in interaction with body mass. The duration of the first feeding was affected only by foragers' body mass. Our finding indicates that chronic exposure to a high but field‐realistic concentration of acetamiprid may alter some aspects of bumblebees' foraging behaviour. If such behavioural changes accumulate during consecutive foraging bouts, chronic exposure to this pesticide might lead to a reduction of daily resource collection, ultimately jeopardising colony fitness or plant (crop) pollination. [ABSTRACT FROM AUTHOR]

Social bees are frequently exposed to pesticides when foraging on nectar and pollen. Recent research has shown that pesticide exposure not only impacts social bee host health but can also alter the community structure of social bee gut microbiotas. However, most research on pesticide-bee gut microbiota interactions has been conducted in honey bees; bumble bees, native North American pollinators, have received less attention and, due to differences in their ecology, may be exposed to certain pesticides for shorter durations than honey bees. Here, we examine how exposure to the fungicide chlorothalonil for a short, field-realistic duration alters bumble bee fecal microbiotas (used as a proxy for gut microbiotas) and host performance. We expose small groups of Bombus impatiens workers (microcolonies) to field-re alistic chlorothalonil concentrations for 5 days, track changes in fecal microbiotas during the exposure period and a recovery period, and compare microcolony offspring production between treatments at the end of the experiment. We also assess the use of fecal microbiotas as a gut microbiota proxy by comparing community structures of fecal and gut microbiotas. We find that chlorothalonil exposure for a short duration does not alter bumble bee fecal microbiota structure or affect microcolony production at any concentration but that fecal and gut microbiotas differ significantly in community structure. Our results show that, at least when exposure durations are brief and unaccompanied by other stressors, bumble bee microbiotas are resilient to fungicide exposure. Additionally, our work highlights the importance of sampling gut microbiotas directly, when possible. [ABSTRACT FROM AUTHOR]

Invasive species are predicted to adjust their morphological, physiological and life‐history traits to adapt to their non‐native environments. Although a loss of genetic variation during invasion may restrict local adaptation, introduced species often thrive in novel environments. Despite being founded by just a few individuals, Bombus terrestris (Hymenoptera: Apidae) has in less than 30 years successfully spread across the island of Tasmania (Australia), becoming abundant and competitive with native pollinators. We use RADseq to investigate what neutral and adaptive genetic processes associated with environmental and morphological variation allow B. terrestris to thrive as an invasive species in Tasmania. Given the widespread abundance of B. terrestris, we expected little genetic structure across Tasmania and weak signatures of environmental and morphological selection. We found high gene flow with low genetic diversity, although with significant isolation‐by‐distance and spatial variation in effective migration rates. Restricted migration was evident across the mid‐central region of Tasmania, corresponding to higher elevations, pastural land, low wind speeds and low precipitation seasonality. Tajima's D indicated a recent population expansion extending from the south to the north of the island. Selection signatures were found for loci in relation to precipitation, wind speed and wing loading. Candidate loci were annotated to genes with functions related to cuticle water retention and insect flight muscle stability. Understanding how a genetically impoverished invasive bumblebee has rapidly adapted to a novel island environment provides further understanding about the evolutionary processes that determine successful insect invasions, and the potential for invasive hymenopteran pollinators to spread globally. [ABSTRACT FROM AUTHOR]

Flowers cluster at various spatial scales, so pollinators use information from multiple scales when foraging in natural plant populations. Little is known about the effects of interactions between scales or their relative strength. We examined bumblebee foraging behaviour in a natural population of Salvia nipponica in 10 and 7 patches in 2019 and 2020, respectively. We recorded within-patch factors (display size of racemes and local open raceme densities) and patch-level factors (patch size and distance from the nearest patch) and analysed their relationships with pollinator behaviour. The numbers of visits per raceme and flower were mainly affected by the interaction of patch size and raceme density; they were higher in locations with lower raceme density in larger patches. The ratio of flowers visited to all open flowers in a raceme during a raceme visit, which relates to a bumblebee's choice to leave a raceme, was mainly affected by the interaction of display size and local open raceme density; in 2019 it was higher in racemes with smaller display sizes, while in 2020 the strength and direction of the relationship depended on the open raceme density. These results suggest that pollinators relied on the sizes of flower clusters at different spatial scales when visiting and leaving racemes and adjusted their responses to the sizes of flower clusters depending on the distances between clusters. Therefore, it is important to evaluate factors at various spatial scales and their interactions to fully understand pollinator behaviour in natural plant populations. [ABSTRACT FROM AUTHOR]

Conversion of land for agricultural use is a leading driver of global biodiversity loss. Natural and semi‐natural lands within agricultural landscapes are targeted for protection because they provide habitat for many organisms.Pothole (or kettle) wetlands occur across the Northern Hemisphere and are a focus for conservation both because of their location within agriculturally intensive landscapes and their importance to vertebrates, especially migratory birds.Recent evidence suggests that wetlands may also be an important habitat for arthropods, including insects that provide ecosystem services. To understand how insects associate with wetlands and landscape features, we examine the relationship between bumblebees (Bombus), and wetland area, cropland area and wetland perimeter‐area ratio.We found that wetland area is significantly positively associated with the occurrence and abundance of the species studied. We also found that the relationship between bumblebees and wetland perimeter‐area ratio varied across the growing season. This suggests that the importance of wetland edge as a foraging habitat varies across the season.These results show the utility of wetlands to bees, though their resources are likely not being used uniformly by all bumblebee species or across the entire growing season. Our results also suggest that pothole wetlands in agricultural landscapes are likely to support biodiversity, and their conservation contributes to overall ecosystem health and function. [ABSTRACT FROM AUTHOR]

Foraging theory assumes that animals assess value based on objective payoffs; however, animals often evaluate rewards comparatively, forming expectations based on recent experience. This form of evaluation may be particularly relevant for nectar foragers such as bumblebees, where individuals can visit thousands of flowers daily that vary in nectar quality. While many animals, including bees, demonstrate reference-based evaluation in experimental contexts, it is unclear whether this occurs in the wild. Here, we asked how daily experience with wildflower nectar influenced wild bumblebees' reward evaluation. We measured the daily nectar concentration of bee-visited wildflowers (Penstemon spp.), before presenting foragers with conspecific flowers filled with a range of artificial nectar concentrations. We recorded bees' acceptance of artificial nectar, the probability of subsequent visits to flowers on the same plant, and residence time. While bees had a minimum threshold of nectar acceptability that was unaffected by experience, when there was higher-concentration environmental nectar, they were less likely to accept lower-quality rewards on manipulated plants. Bees also visited more flowers and stayed longer on plants with higher-concentration nectar. This study shows evidence for both absolute and reference-based evaluation in wild bees and points towards differences between bees' behavior in lab- and wild-foraging contexts. [ABSTRACT FROM AUTHOR]

This document is a corrigendum published in the journal Frontiers in Insect Science. It corrects an error in Figure 1 of the article titled "Acute imidacloprid exposure alters mitochondrial function in bumblebee flight muscle and brain." The corrected figure and its caption are provided, and the authors apologize for the error. The corrigendum also includes a note from the publisher stating that the views expressed in the article are solely those of the authors and do not necessarily represent the views of their affiliated organizations or the publisher. The article is open access and can be cited under the terms of the Creative Commons Attribution License. [Extracted from the article]

Crithidia bombi is a trypanosomatid parasite that infects several species of bumble bees (Bombus spp.), by adhering to their intestinal tract. Crithidia bombi infection impairs learning and reduces survival of workers and the fitness of overwintering queens. Although there is extensive research on the ecology of this host-pathogen system, we understand far less about the mechanisms that mediate internal infection dynamics. Crithidia bombi infects hosts by attaching to the hindgut via the flagellum, and one previous study found that a nectar secondary compound removed the flagellum, preventing attachment. However, approaches that allow more detailed observation of parasite attachment and growth would allow us to better understand factors mediating this host-pathogen relationship. We established techniques for genetic manipulation and visualization of cultured C. bombi. Using constructs established for Crithidia fasciculata, we successfully generated C. bombi cells expressing ectopic fluorescent transgenes using two different selectable markers. To our knowledge, this is the first genetic modification of this species. We also introduced constructs that label the mitochondrion and nucleus of the parasite, showing that subcellular targeting signals can function across parasite species to highlight specific organelles. Finally, we visualized fluorescently tagged parasites in vitro in both their swimming and attached forms, and in vivo in bumble bee (Bombus impatiens) hosts. Expanding our cell and molecular toolkit for C. bombi will help us better understand how factors such as host diet, immune system, and physiology mediate outcomes of infection by these common parasites. [Display omitted] • First described method for genetic modification of the bee parasite Crithidia bombi. • Ectopic transgenes can be introduced using multiple selectable markers. • Cytoplasmic and organelle markers can be visualized in swimming and attached developmental forms. • Simplified method for culture adaptation of parasites from bees for subsequent modification. • Imaging of fluorescent C. bombi parasites in vivo in the bumble bee Bombus impatiens. [ABSTRACT FROM AUTHOR]

Bees are declining, which is worrisome since they both have intrinsic conservation value and play a major role as pollinators in both natural and managed ecosystems. Land use change and lack of suitable habitats are often suggested as driving forces of bee decline. To propose mitigation measures to halt bee decline, it is important to understand how land use relates to bee abundance and diversity, and to explore consequences for their provision of pollination services. White clover, Trifolium repens , is an outcrossing mass-flowering crop, which could serve as an abundant, although ephemeral, food resource for bees. We investigated how the bee community in 39 fields of white clover grown for seed, related to local field management (organic, conventional without insecticides and conventional with insecticides) and landscape context (proportion semi-natural land), and how this pollinator community related to white clover seed set. The honey bee, Apis mellifera , was the most commonly observed bee species, and two generalist bumble bee species, Bombus terrestris and B. lapidarius , were the subsequently most common. We observed fewer non- Apis bees, and a lower bee species richness in organic white clover seed fields compared to conventional fields independent of insecticide treatment. Bee species richness in both conventional and organic fields were positively related to the proportion of semi-natural land in the landscape, likely because of a larger species pool in such landscapes. Initial seed set in immature inflorescences was positively related to bee abundance, whereas final seed set in mature inflorescences was unrelated to bee abundance, possibly as a consequence of seed-eating weevils consuming a large proportion of the seeds. We conclude that both bee visitation and seed set in white clover benefit from conventional management and that landscapes rich in semi-natural habitats will make future crop production more resilient. The observed positive relationship between bee abundance and initial seed set suggests that if we can mitigate pest impacts and increase bee abundance in clover seed fields, the final seed yield can be increased. Thus, bee decline should be considered and mitigated both to maintain biodiversity in general and for crop seed production specifically. • Lower (non-Apis) bee abundance and species richness in organic white clover fields • Bee species richness positively related to the proportion of semi-natural land • Initial seed set in immature inflorescences positively related to bee abundance • Final seed set was unrelated to bee abundance, possibly due to seed-eating weevils [ABSTRACT FROM AUTHOR]

Cadmium pollution affects the global ecosystem because cadmium can be transferred up the food chain. The bumblebee, Bombus terrestris , is an important insect pollinator. Their foraging activity on flowers exposes them to harmful heavy metals, which damages their health and leads to massive population declines. However, the effects of chronic exposure to heavy metals on the flight performance of bumblebees have not yet been characterized. Here, we studied variation in the flight capacity of bumblebees induced by chronic cadmium exposure at field-realistic concentrations using behavioral, physiological, and molecular approaches. Chronic cadmium exposure caused a significant reduction in the duration, distance, and mean velocity of bumblebee flight. Transcriptome analysis showed that the impairment of carbon metabolism and mitochondrial dysfunction in the flight muscle were the primary causes. Physiological, biochemical, and metabolomic analyses validated disruptions in energy metabolism, and impairments in mitochondrial respiratory chain complexes activities. Histological analysis revealed muscle fiber damage and mitochondrial loss. Exogenous decanoic acid or citric acid partially restored sustained flight ability of bumblebees by mitigating muscle fiber damage and increasing energy generation. These findings provide insights into how long-term cadmium stress affects the flight ability of insects and will aid human muscle or exercise-related disease research. [Display omitted] • Chronic cadmium exposure at field-realistic concentrations reduced flight capacity. • Chronic cadmium exposure impaired sustained flight by inhibiting energy metabolism. • Citrate synthase was a potential biomarker for chronic cadmium exposure. • Exogenous citric acid or decanoic acid restored damaged flight ability. [ABSTRACT FROM AUTHOR]

"What a Bee Knows: Exploring the Thoughts, Memories, and Personalities of Bees" by Stephen Buchmann is a book that sheds light on the remarkable abilities of bees and their brains. The author covers the basics of bee biology, including how they find food, build nests, interact with each other, and find mates. The book also delves into cutting-edge research on bee learning, cognition, self-awareness, and consciousness. While the book does not provide detailed information on pollinator habitat restoration or conservation resources, it emphasizes the importance of taking action to support bees and other pollinators. Overall, readers will gain a newfound appreciation for bees and their complex lives. [Extracted from the article]