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Sample records for bee bombus terrestris

  1. Detection of Deformed wing virus, a honey bee viral pathogen, in bumble bees (Bombus terrestris and Bombus pascuorum) with wing deformities.

    PubMed

    Genersch, Elke; Yue, Constanze; Fries, Ingemar; de Miranda, Joachim R

    2006-01-01

    Honey bees (Apis mellifera) productively infected with Deformed wing virus (DWV) through Varroa destructor (V. destructor) during pupal stages develop into adults showing wing and other morphological deformities. Here, we report for the first time the occurrence of bumble bees (Bombus terrestris, Bombus pascuorum) exhibiting wing deformities resembling those seen in clinically DWV-infected honey bees. Using specific RT-PCR protocols for the detection of DWV followed by sequencing of the PCR products we could demonstrate that the bumble bees were indeed infected with DWV. Since such deformed bumble bees are not viable DWV infection may pose a serious threat to bumble bee populations.

  2. Lateralization in the invertebrate brain: left-right asymmetry of olfaction in bumble bee, Bombus terrestris.

    PubMed

    Anfora, Gianfranco; Rigosi, Elisa; Frasnelli, Elisa; Ruga, Vincenza; Trona, Federica; Vallortigara, Giorgio

    2011-04-27

    Brain and behavioural lateralization at the population level has been recently hypothesized to have evolved under social selective pressures as a strategy to optimize coordination among asymmetrical individuals. Evidence for this hypothesis have been collected in Hymenoptera: eusocial honey bees showed olfactory lateralization at the population level, whereas solitary mason bees only showed individual-level olfactory lateralization. Here we investigated lateralization of odour detection and learning in the bumble bee, Bombus terrestris L., an annual eusocial species of Hymenoptera. By training bumble bees on the proboscis extension reflex paradigm with only one antenna in use, we provided the very first evidence of asymmetrical performance favouring the right antenna in responding to learned odours in this species. Electroantennographic responses did not reveal significant antennal asymmetries in odour detection, whereas morphological counting of olfactory sensilla showed a predominance in the number of olfactory sensilla trichodea type A in the right antenna. The occurrence of a population level asymmetry in olfactory learning of bumble bee provides new information on the relationship between social behaviour and the evolution of population-level asymmetries in animals.

  3. Effects of imidacloprid, a neonicotinoid pesticide, on reproduction in worker bumble bees (Bombus terrestris).

    PubMed

    Laycock, Ian; Lenthall, Kate M; Barratt, Andrew T; Cresswell, James E

    2012-10-01

    Bumble bees are important pollinators whose populations have declined over recent years, raising widespread concern. One conspicuous threat to bumble bees is their unintended exposure to trace residues of systemic neonicotinoid pesticides, such as imidacloprid, which are ingested when bees forage on the nectar and pollen of treated crops. However, the demographic consequences for bumble bees of exposure to dietary neonicotinoids have yet to be fully established. To determine whether environmentally realistic levels of imidacloprid are capable of making a demographic impact on bumble bees, we exposed queenless microcolonies of worker bumble bees, Bombus terrestris, to a range of dosages of dietary imidacloprid between zero and 125 μg L(-1) and examined the effects on ovary development and fecundity. Microcolonies showed a dose-dependent decline in fecundity, with environmentally realistic dosages in the range of 1 μg L(-1) capable of reducing brood production by one third. In contrast, ovary development was unimpaired by dietary imidacloprid except at the highest dosage. Imidacloprid reduced feeding on both syrup and pollen but, after controlling statistically for dosage, microcolonies that consumed more syrup and pollen produced more brood. We therefore speculate that the detrimental effects of imidacloprid on fecundity emerge principally from nutrient limitation imposed by the failure of individuals to feed. Our findings raise concern about the impact of neonicotinoids on wild bumble bee populations. However, we recognize that to fully evaluate impacts on wild colonies it will be necessary to establish the effect of dietary neonicotinoids on the fecundity of bumble bee queens.

  4. Social regulation of maternal traits in nest-founding bumble bee (Bombus terrestris) queens

    PubMed Central

    Woodard, S. Hollis; Bloch, Guy; Band, Mark R.; Robinson, Gene E.

    2013-01-01

    SUMMARY During the nest-founding phase of the bumble bee colony cycle, queens undergo striking changes in maternal care behavior. Early in the founding phase, prior to the emergence of workers in the nest, queens are reproductive and also provision and feed their offspring. However, later in the founding phase, queens reduce their feeding of larvae and become specialized on reproduction. This transition is synchronized with the emergence of workers in the colony, who assume the task of feeding their siblings. Using a social manipulation experiment with the bumble bee Bombus terrestris, we tested the hypothesis that workers regulate the transition from feeding brood to specialization on reproduction in nest-founding bumble bee queens. Consistent with this hypothesis, we found that early-stage nest-founding queens with workers prematurely added to their nests reduce their brood-feeding behavior and increase egg laying, and likewise, late-stage nest-founding queens increase their brood-feeding behavior and decrease egg-laying when workers are removed from their nests. Further, brood-feeding and egg-laying behaviors were negatively correlated. We used Agilent microarrays designed from B. terrestris brain expressed sequenced tags (ESTs) to explore a second hypothesis, that workers alter brain gene expression in nest-founding queens. We found evidence that brain gene expression in nest-founding queens is altered by the presence of workers, with the effect being much stronger in late-stage founding queens. This study provides new insights into how the transition from feeding brood to specialization on reproduction in queen bumble bees is regulated during the nest initiation phase of the colony cycle. PMID:23966589

  5. Kin-selected conflict in the bumble-bee Bombus terrestris (Hymenoptera: Apidae).

    PubMed Central

    Bourke, A. F.; Ratnieks, F. L.

    2001-01-01

    Kin selection theory predicts conflict in social Hymenoptera between the queen and workers over male parentage because each party is more closely related to its own male offspring. Some aspects of the reproductive biology of the bumble-bee Bombus terrestris support kin selection theory but others arguably do not. We present a novel hypothesis for how conflict over male parentage should unfold in B. terrestris colonies. We propose that workers delay laying eggs until they possess information showing that egg laying suits their kin-selected interests. In colonies where queens start to lay haploid eggs early, we hypothesize that this occurs when workers detect the presence of queen-produced male brood in the brood's larval stage. In colonies where queens start to lay haploid eggs late, we hypothesize that it occurs when workers detect a signal from the queen to female larvae to commence development as queens. Our hypothesis accounts for previously unexplained aspects of the timing of reproductive events in B. terrestris, provides ultimate explanations for the results of a recent study of mechanisms underlying queen-worker conflict and helps explain this species' characteristic bimodal (split) sex ratios. Therefore, kin selection theory potentially provides a good explanation for reproductive patterns in B. terrestris. PMID:11270430

  6. Changes in Learning and Foraging Behaviour within Developing Bumble Bee (Bombus terrestris) Colonies

    PubMed Central

    Evans, Lisa J.; Raine, Nigel E.

    2014-01-01

    Organisation in eusocial insect colonies emerges from the decisions and actions of its individual members. In turn, these decisions and actions are influenced by the individual's behaviour (or temperament). Although there is variation in the behaviour of individuals within a colony, we know surprisingly little about how (or indeed if) the types of behaviour present in a colony change over time. Here, for the first time, we assessed potential changes in the behavioural type of foragers during colony development. Using an ecologically relevant foraging task, we measured the decision speed and learning ability of bumble bees (Bombus terrestris) at different stages of colony development. We determined whether individuals that forage early in the colony life cycle (the queen and early emerging workers) behaved differently from workers that emerge and forage at the end of colony development. Whilst we found no overall change in the foraging behaviour of workers with colony development, there were strong differences in foraging behaviour between queens and their workers. Queens appeared to forage more cautiously than their workers and were also quicker to learn. These behaviours could allow queens to maximise their nectar collecting efficiency whilst avoiding predation. Because the foundress queen is crucial to the survival and success of a bumble bee colony, more efficient foraging behaviour in queens may have strong adaptive value. PMID:24599144

  7. Effects of the neonicotinoid pesticide thiamethoxam at field-realistic levels on microcolonies of Bombus terrestris worker bumble bees.

    PubMed

    Laycock, Ian; Cotterell, Katie C; O'Shea-Wheller, Thomas A; Cresswell, James E

    2014-02-01

    Neonicotinoid pesticides are currently implicated in the decline of wild bee populations. Bumble bees, Bombus spp., are important wild pollinators that are detrimentally affected by ingestion of neonicotinoid residues. To date, imidacloprid has been the major focus of study into the effects of neonicotinoids on bumble bee health, but wild populations are increasingly exposed to alternative neonicotinoids such as thiamethoxam. To investigate whether environmentally realistic levels of thiamethoxam affect bumble bee performance over a realistic exposure period, we exposed queenless microcolonies of Bombus terrestris L. workers to a wide range of dosages up to 98 μgkg(-1) in dietary syrup for 17 days. Results showed that bumble bee workers survived fewer days when presented with syrup dosed at 98 μg thiamethoxamkg(-1), while production of brood (eggs and larvae) and consumption of syrup and pollen in microcolonies were significantly reduced by thiamethoxam only at the two highest concentrations (39, 98 μgkg(-1)). In contrast, we found no detectable effect of thiamethoxam at levels typically found in the nectars of treated crops (between 1 and 11 μgkg(-1)). By comparison with published data, we demonstrate that during an exposure to field-realistic concentrations lasting approximately two weeks, brood production in worker bumble bees is more sensitive to imidacloprid than thiamethoxam. We speculate that differential sensitivity arises because imidacloprid produces a stronger repression of feeding in bumble bees than thiamethoxam, which imposes a greater nutrient limitation on production of brood. © 2013 Published by Elsevier Inc.

  8. A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris

    PubMed Central

    Dutka, Alexandrea; McNulty, Alison

    2015-01-01

    There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm2 soil. Of particular concern is the fact that nematodes from the broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment. PMID:26618084

  9. Synergistic interactions between a variety of insecticides and an EBI fungicide in dietary exposures of bumble bees (Bombus terrestris L.).

    PubMed

    Raimets, Risto; Karise, Reet; Mänd, Marika; Kaart, Tanel; Ponting, Sally; Song, Jimao; Cresswell, James E

    2017-10-09

    In recent years, concern has been raised over honey bee colony losses, and also among wild bees there is evidence for extinctions and range contractions in Europe and North America. Pesticides have been proposed as a potential cause of this decline. Bees are exposed simultaneously to variety of agrochemicals, which may cause synergistically detrimental impacts, which are incompletely understood. We investigated the toxicity of the fungicide imazalil in mixture with four common insecticides: fipronil (phenylpyrazoid); cypermethrin (pyrethroid); thiamethoxam; and imidacloprid (neonicotinoids). EBI fungicides like imazalil can inhibit P450 detoxification systems in insects and therefore fungicide-insecticide co-occurrence might produce synergistic toxicity in bees. We assessed the impact of dietary fungicide-insecticide mixtures on the mortality and feeding rates of laboratory bumble bees (Bombus terrestris L.). Regarding mortality, imazalil synergised the toxicity of fipronil, cypermethrin and thiamethoxam, but not imidacloprid. We found no synergistic effects on feeding rates. Our findings suggest that P450-based detoxification processes are differentially important in mitigating the toxicity of certain insecticides, even those of the same chemical class. Our evidence that cocktail effects can arise in bumble bees should extend concern over the potential impacts of agrochemical mixtures to include wild bee species in farmland. This article is protected by copyright. All rights reserved.

  10. A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris.

    PubMed

    Dutka, Alexandrea; McNulty, Alison; Williamson, Sally M

    2015-01-01

    There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm(2) soil. Of particular concern is the fact that nematodes from the broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment.

  11. A Novel Behavioral Assay to Investigate Gustatory Responses of Individual, Freely-moving Bumble Bees (Bombus terrestris).

    PubMed

    Ma, Carolyn; Kessler, Sébastien; Simpson, Alexander; Wright, Geraldine

    2016-07-21

    Generalist pollinators like the buff-tailed bumble bee, Bombus terrestris, encounter both nutrients and toxins in the floral nectar they collect from flowering plants. Only a few studies have described the gustatory responses of bees toward toxins in food, and these experiments have mainly used the proboscis extension response on restrained honey bees. Here, a new behavioral assay is presented for measuring the feeding responses of freely-moving, individual worker bumble bees to nutrients and toxins. This assay measures the amount of solution ingested by each bumble bee and identifies how tastants in food influence the microstructure of the feeding behavior. The solutions are presented in a microcapillary tube to individual bumble bees that have been previously starved for 2-4 hr. The behavior is captured on digital video. The fine structure of the feeding behavior is analyzed by continuously scoring the position of the proboscis (mouthparts) from video recordings using event logging software. The position of the proboscis is defined by three different behavioral categories: (1) proboscis is extended and in contact with the solution, (2) proboscis is extended but not in contact with the solution and (3) proboscis is stowed under the head. Furthermore the speed of the proboscis retracting away from the solution is also estimated. In the present assay the volume of solution consumed, the number of feeding bouts, the duration of the feeding bouts and the speed of the proboscis retraction after the first contact is used to evaluate the phagostimulatory or the deterrent activity of the compounds tested. This new taste assay will allow researchers to measure how compounds found in nectar influence the feeding behavior of bees and will also be useful to pollination biologists, toxicologists and neuroethologists studying the bumble bee's taste system.

  12. A Novel Behavioral Assay to Investigate Gustatory Responses of Individual, Freely-moving Bumble Bees (Bombus terrestris)

    PubMed Central

    Ma, Carolyn; Kessler, Sébastien; Simpson, Alexander; Wright, Geraldine

    2016-01-01

    Generalist pollinators like the buff-tailed bumble bee, Bombus terrestris, encounter both nutrients and toxins in the floral nectar they collect from flowering plants. Only a few studies have described the gustatory responses of bees toward toxins in food, and these experiments have mainly used the proboscis extension response on restrained honey bees. Here, a new behavioral assay is presented for measuring the feeding responses of freely-moving, individual worker bumble bees to nutrients and toxins. This assay measures the amount of solution ingested by each bumble bee and identifies how tastants in food influence the microstructure of the feeding behavior. The solutions are presented in a microcapillary tube to individual bumble bees that have been previously starved for 2-4 hr. The behavior is captured on digital video. The fine structure of the feeding behavior is analyzed by continuously scoring the position of the proboscis (mouthparts) from video recordings using event logging software. The position of the proboscis is defined by three different behavioral categories: (1) proboscis is extended and in contact with the solution, (2) proboscis is extended but not in contact with the solution and (3) proboscis is stowed under the head. Furthermore the speed of the proboscis retracting away from the solution is also estimated. In the present assay the volume of solution consumed, the number of feeding bouts, the duration of the feeding bouts and the speed of the proboscis retraction after the first contact is used to evaluate the phagostimulatory or the deterrent activity of the compounds tested. This new taste assay will allow researchers to measure how compounds found in nectar influence the feeding behavior of bees and will also be useful to pollination biologists, toxicologists and neuroethologists studying the bumble bee's taste system. PMID:27500630

  13. Repression and Recuperation of Brood Production in Bombus terrestris Bumble Bees Exposed to a Pulse of the Neonicotinoid Pesticide Imidacloprid

    PubMed Central

    Laycock, Ian; Cresswell, James E.

    2013-01-01

    Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days ‘on dose’ followed by 14 days ‘off dose’) to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae) produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers). During the initial ‘on dose’ period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg−1 dietary imidacloprid. During the following ‘off dose’ period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg−1. Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop. PMID:24224015

  14. Repression and recuperation of brood production in Bombus terrestris bumble bees exposed to a pulse of the neonicotinoid pesticide imidacloprid.

    PubMed

    Laycock, Ian; Cresswell, James E

    2013-01-01

    Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days 'on dose' followed by 14 days 'off dose') to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae) produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers). During the initial 'on dose' period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg(-1) dietary imidacloprid. During the following 'off dose' period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg(-1). Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop.

  15. Effect of oral infection with Kashmir bee virus and Israeli acute paralysis virus on bumblebee (Bombus terrestris) reproductive success.

    PubMed

    Meeus, Ivan; de Miranda, Joachim R; de Graaf, Dirk C; Wäckers, Felix; Smagghe, Guy

    2014-09-01

    Israeli acute paralysis virus (IAPV) together with Acute bee paralysis virus (ABPV) and Kashmir bee virus (KBV) constitute a complex of closely related dicistroviruses. They are infamous for their high mortality after injection in honeybees. These viruses have also been reported in non-Apis hymenopteran pollinators such as bumblebees, which got infected with IAPV when placed in the same greenhouse with IAPV infected honeybee hives. Here we orally infected Bombus terrestris workers with different doses of either IAPV or KBV viral particles. The success of the infection was established by analysis of the bumblebees after the impact studies: 50days after infection. Doses of 0.5×10(7) and 1×10(7) virus particles per bee were infectious over this period, for IAPV and KBV respectively, while a dose of 0.5×10(6) IAPV particles per bee was not infectious. The impact of virus infection was studied in micro-colonies consisting of 5 bumblebees, one of which becomes a pseudo-queen which proceeds to lay unfertilized (drone) eggs. The impact parameters studied were: the establishment of a laying pseudo-queen, the timing of egg-laying, the number of drones produced, the weight of these drones and worker mortality. In this setup KBV infection resulted in a significant slower colony startup and offspring production, while only the latter can be reported for IAPV. Neither virus increased worker mortality, at the oral doses used. We recommend further studies on how these viruses transmit between different pollinator species. It is also vital to understand how viral prevalence can affect wild bee populations because disturbance of the natural host-virus association may deteriorate the already critically endangered status of many bumblebee species.

  16. Reproductive competition in the bumble-bee Bombus terrestris: do workers advertise sterility?

    PubMed

    Amsalem, Etya; Twele, Robert; Francke, Wittko; Hefetz, Abraham

    2009-04-07

    Reproductive competition in social insects is generally mediated through specific fertility pheromones. By analysing Dufour's gland secretion in queens and workers of Bombus terrestris under varying social conditions, we demonstrate here that the volatile constituents of the secretion exhibit a context-dependent composition. The secretion of egg-laying queens is composed of a series of aliphatic hydrocarbons (alkanes and alkenes), while that of sterile workers contains in addition octyl esters, dominated by octyl hexadecanoate and octyl oleate. These esters disappear in workers with developed ovaries, whether queenright (QR) or queenless (QL), rendering their secretion queen-like. This constitutes an unusual case in which the sterile caste, rather than the fertile one, possesses extra components. Individually isolated (socially deprived) workers developed ovaries successfully, but failed to oviposit, and still possessed the octyl esters. Thus, whereas social interactions are not needed in order to develop ovaries, they appear essential for oviposition and compositional changes in Dufour's gland secretion (ester disappearance). The apparent link between high ester levels and an inability to lay eggs lends credence to the hypothesis that these esters signal functional sterility. We hypothesize that by producing a sterility-specific secretion, workers signal that 'I am out of the competition', and therefore are not attacked, either by the queen or by the reproductive workers. This enables proper colony function and brood care, in particular sexual brood, even under the chaotic conditions of the competition phase.

  17. Clearance of ingested neonicotinoid pesticide (imidacloprid) in honey bees (Apis mellifera) and bumblebees (Bombus terrestris).

    PubMed

    Cresswell, James E; Robert, François-Xavier L; Florance, Hannah; Smirnoff, Nicholas

    2014-02-01

    Bees in agricultural landscapes are exposed to dietary pesticides such as imidacloprid when they feed from treated mass-flowering crops. Concern about the consequent impact on bees makes it important to understand their resilience. In the laboratory, the authors therefore fed adult worker bees on dosed syrup (125 μg L(-1) of imidacloprid, or 98 μg kg(-1)) either continuously or as a pulsed exposure and measured their behaviour (feeding and locomotory activity) and whole-body residues. On dosed syrup, honey bees maintained much lower bodily levels of imidacloprid than bumblebees (<0.2 ng versus 2.4 ng of imidacloprid per bee). Dietary imidacloprid did not affect the behaviour of honey bees, but it reduced feeding and locomotory activity in bumblebees. After the pulsed exposure, bumblebees cleared bodily imidacloprid after 48 h and recovered behaviourally. The differential behavioural resilience of the two species can be attributed to the observed differential in bodily residues. The ability of bumblebees to recover may be environmentally relevant in wild populations that face transitory exposures from the pulsed blooming of mass-flowering crops. © 2013 Society of Chemical Industry.

  18. Effects of Fastac 50 EC on bumble bee Bombus terrestris L. respiration: DGE disappearance does not lead to increasing water loss.

    PubMed

    Muljar, Riin; Karise, Reet; Viik, Eneli; Kuusik, Aare; Williams, Ingrid; Metspalu, Luule; Hiiesaar, Külli; Must, Anne; Luik, Anne; Mänd, Marika

    2012-11-01

    Sublethal effects of pesticides in insects can be observed through physiological changes, which are commonly estimated by metabolic rate and respiratory patterns, more precisely by the patterns of discontinuous gas-exchange (DGE) cycles. The aim of the present research was to study the effect of some low concentrations of Fastac 50 EC on the cycles of CO(2) release and respiratory water loss rates (WLR) in bumble bee Bombus terrestris L. foragers. Bumble bees were dipped into 0.004% and 0.002% Fastac 50 EC solution. Flow-through respirometry was used to record the respiration and WLR 3h before and after the treatment. The respirometry was combined with infrared actography to enable simultaneous recording of abdominal movements. Our results show that Fastac 50 EC has an after-effect on bumble bee respiratory rhythms and muscle activity but does not affect WLR. Treatment with 0.004% Fastac 50 EC solution resulted in disappearance of the respiration cycles; also the lifespan of treated bumble bees was significantly shorter. Treatment with 0.002% Fastac 50 EC solution had no significant effect on respiration patterns or longevity. We found no evidence for the DGE cycles functioning as a water saving mechanism. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Condition-dependent virulence of slow bee paralysis virus in Bombus terrestris: are the impacts of honeybee viruses in wild pollinators underestimated?

    PubMed

    Manley, Robyn; Boots, Mike; Wilfert, Lena

    2017-06-01

    Slow bee paralysis virus (SBPV)-previously considered an obligate honeybee disease-is now known to be prevalent in bumblebee species. SBPV is highly virulent in honeybees in association with Varroa mites, but has been considered relatively benign otherwise. However, condition-dependent pathogens can appear asymptomatic under good, resource abundant conditions, and negative impacts on host fitness may only become apparent when under stressful or resource-limited conditions. We tested whether SBPV expresses condition-dependent virulence in its bumblebee host, Bombus terrestris, by orally inoculating bees with SBPV and recording longevity under satiated and starvation conditions. SBPV infection resulted in significant virulence under starvation conditions, with infected bees 1.6 times more likely to die at any given time point (a median of 2.3 h earlier than uninfected bees), whereas there was no effect under satiated conditions. This demonstrates clear condition-dependent virulence for SBPV in B. terrestris. Infections that appear asymptomatic in non-stressful laboratory assays may nevertheless have significant impacts under natural conditions in the wild. For multi-host pathogens such as SBPV, the use of sentinel host species in laboratory assays may further lead to the underestimation of pathogen impacts on other species in nature. In this case the impact of 'honeybee viruses' on wild pollinators may be underestimated, with detrimental effects on conservation and food security. Our results highlight the importance of multiple assays and multiple host species when testing for virulence, in order for laboratory studies to accurately inform conservation policy and mitigate disease impacts in wild pollinators.

  20. Large-scale monitoring of effects of clothianidin-dressed OSR seeds on pollinating insects in Northern Germany: effects on large earth bumble bees (Bombus terrestris).

    PubMed

    Sterk, Guido; Peters, Britta; Gao, Zhenglei; Zumkier, Ulrich

    2016-11-01

    The aim of this study was to investigate the effects of Elado(®)-dressed winter oilseed rape (OSR, 10 g clothianidin & 2 g beta-cyfluthrin/kg seed) on the development, reproduction and behaviour of large earth bumble bees (Bombus terrestris) as part of a large-scale monitoring field study in Northern Germany, where OSR is usually cultivated at 25-33 % of the arable land. Both reference and test sites comprised 65 km(2) in which no other crops attractive to pollinating insects were present. Six study locations were selected per site and 10 bumble bee hives were placed at each location. At each site, three locations were directly adjacent to OSR fields and three locations were situated 400 m distant from the nearest OSR field. The development of colonies was monitored from the beginning of OSR flowering in April until June 2014. Pollen from returning foragers was analysed for its composition. An average of 44 % of OSR pollen was found in pollen loads of bumble bees indicating that OSR was a major resource for the colonies. At the end of OSR flowering, hives were transferred to a nature reserve until the end of the study. Colony development in terms of hive weight and the number of workers showed a typical course with no statistically significant differences between the sites. Reproductive output was comparatively high and not negatively affected by the exposure to treated OSR. In summary, Elado(®)-dressed OSR did not cause any detrimental effects on the development or reproduction of bumble bee colonies.

  1. Spatial Vision in Bombus terrestris

    PubMed Central

    Chakravarthi, Aravin; Baird, Emily; Dacke, Marie; Kelber, Almut

    2016-01-01

    Bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. Two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. In this study, we report the threshold of spatial resolution in B. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. We trained bumblebees in a Y-maze experimental set-up to associate a vertical sinusoidal grating with a sucrose reward, and a horizontal grating with absence of a reward. Using a logistic psychometric function, we estimated a resolution threshold of 0.21 cycles deg−1 of visual angle. This resolution is in the same range but slightly lower than that found in honeybees (Apis mellifera and A. cerana) and another bumblebee species (B. impatiens). We also found that the contrast sensitivity of B. terrestris was 1.57 for the spatial frequency 0.090 cycles deg−1 and 1.26 for 0.18 cycles deg−1. PMID:26912998

  2. Bee pathogens found in Bombus atratus from Colombia: A case study.

    PubMed

    Gamboa, Viviana; Ravoet, Jorgen; Brunain, Marleen; Smagghe, Guy; Meeus, Ivan; Figueroa, Judith; Riaño, Diego; de Graaf, Dirk C

    2015-07-01

    Bombus atratus bumblebees from Colombia that were caught in the wild and from breeding programs were screened for a broad set of bee pathogens. We discovered for the first time Lake Sinai Virus and confirmed the infection by other common viruses. The prevalence of Apicystis bombi, Crithidia bombi and Nosema ceranae was remarkably high. According to other studies the former two could have been co-introduced in South America with exotic bumble bees as Bombus terrestris or Bombus ruderatus. Given the fact that none of these species occur in Colombia, our data puts a new light on the spread of these pathogens over the South American continent.

  3. The safety of thiamethoxam to pollinating bumble bees (Bombus terrestris L.) when applied to tomato plants through drip irrigation.

    PubMed

    Alarcón, A L; Cánovas, M; Senn, R; Correia, R

    2005-01-01

    Thiamethoxam, mainly sold under the trademark of Actara, is a neonicotinoid widely used in covered vegetables for the control of aphids and whiteflies. In these crops, and particularly in covered tomatoes, bumble-bees are used for cross-pollination as an alternative to labour intensive manual techniques. In this study, made on tomatoes grown in separated greenhouse plots in Murcia, Southern Spain, thiamethoxam was applied through drip irrigation at a rate of 200 g ai/ha, and as a split application of the same rate, to evaluate the effects on pollinating bumble bees compared to a foliar application of a toxic standard. The results showed that the toxic foliar standard had a clear effect on the pollination of tomato flowers, declining to zero pollination two weeks after application, whereas both the single and split drip irrigation applications of Actara had no effect on pollination when compared to the control plots. The count of dead adults and larvae did not show any differences between the treatments, whereas the measurement of sugar water consumption was shown to correlate well with pollination. The consumption of sugar water declined in the toxic standard plots by 69% with respect to the control, whilst the decline in lower dose drip irrigation application was only 3%. In regard to hive weight, and number of adults and brood after destructive sampling; there were no statistical differences between the treatments but a negative effect of the foliar treatment was observed. Based on these results we can conclude that a split application of Actara applied in drip irrigation to the soil/substrate has no effect on the bumble-bees used in tomatoes for pollination.

  4. Altitudinal variation in bumble bee (Bombus) critical thermal limits.

    PubMed

    Oyen, K Jeannet; Giri, Susma; Dillon, Michael E

    2016-07-01

    Organism critical thermal limits are often tightly linked to current geographic distribution and can therefore help predict future range shifts driven by changing environmental temperatures. Thermal tolerance of diverse organisms often varies predictably with latitude, with upper thermal limits changing little and lower thermal limits decreasing with latitude. Despite similarly steep gradients in environmental temperatures across altitude, few studies have investigated altitudinal variation in critical thermal limits. We estimated critical thermal minimum (CTmin), critical thermal maximum (CTmax) and recovery temperature (Trec) by tracking righting response of three bumble bee species during thermal ramps: Bombus huntii collected from 2180m asl, and Bombus bifarius and Bombus sylvicola collected from 3290m asl in Wyoming, USA. Overall, larger bees could tolerate more extreme temperatures, likely due to a thermal inertia driven lag between core body temperatures and air temperatures. Despite their smaller size, high altitude bumble bees tolerated colder air temperatures: they had ~1°C lower CTmin and recovered from cold exposure at ~3-4°C lower air temperatures. Conversely, low altitude bees tolerated ~5°C hotter air temperatures. These altitudinal differences in thermal tolerance parallel differences in average daily minimum (1.2°C) and maximum (7.5°C) temperatures between these sites. These results provide one of the few measurements of organism thermal tolerance across altitude and the first evidence for geographical differences in tolerance of temperature extremes in heterothermic bumble bees.

  5. Bumblebees, humble pollinators or assiduous invaders? A population comparison of foraging performance in Bombus terrestris.

    PubMed

    Ings, Thomas C; Schikora, Juliette; Chittka, Lars

    2005-07-01

    Worldwide trade in non-native bumblebees remains largely unrestricted despite well-documented cases where introductions of non-native bees have gone dramatically wrong. Within Europe, indiscriminate importation of non-native populations of bumblebees (Bombus terrestris) for the pollination of glasshouse crops continues on a massive scale. However, no risk assessment has been conducted for these introductions, perhaps because B. terrestris is considered a native species, so shipping populations from one region to another has been implicitly assumed to present no risk. This view is clearly unjustified because Bombus terrestris populations differ significantly in their genetic makeup as demonstrated by strong differences in coat colour and behavioural traits. Therefore, for the first time we compare an important competitive trait, namely foraging performance, between commercially available B. terrestris populations in contrasting environments. We test whether commercially reared populations differ in their nectar foraging performance and whether this is influenced by both their source environment and the one they are introduced into. We do this by means of a reciprocal transplant experiment. Strong, consistent inter-population differences in performance occurred irrespective of test location: Canary Island bees (B. t. canariensis) were superior to Sardinian bees (B. t. sassaricus), which were generally superior to mainland European bees (B. t. terrestris). These inter-population differences in performance were largely explained by inter-population variation in forager size, with larger bees being superior foragers. However, even when body size was accounted for, "native" bees were not superior to transplanted non-native bees in all but one case. We conclude that non-native populations, especially those with large foragers, can be highly competitive foragers. This could lead to their establishment and displacement of native bees. Therefore, we recommend that

  6. The final moments of landing in bumblebees, Bombus terrestris.

    PubMed

    Reber, Therese; Baird, Emily; Dacke, Marie

    2016-04-01

    In comparison to other insects, like honeybees, bumblebees are very effective pollinators. Even though landing is a crucial part of pollination, little is known about how bumblebees orchestrate the final, critical moments of landing. Here, we use high-speed recordings to capture the fine details of the landing behaviour of free-flying bumblebees (Bombus terrestris), while landing on a flat platform with different orientations. We find that the bees have a fairly constant body and head orientation at the moment of leg extension, irrespective of platform tilt. At the same moment in time, the distance to the platform is held constant at around 8 mm (with the exception of low platform tilts). The orientation of the antennae and the first appendage that touches the platform vary between platform orientations, while the duration of the hover phase does not. Overall, the final moments of landing in bumblebees and their close relatives, the honeybees, are similar. However, the distance to the platform at the moment of leg extension and the duration of the hover phase are different in bumblebees and honeybees, suggesting that they are primarily adapted to land on surfaces with different orientations.

  7. Precocene-I inhibits juvenile hormone biosynthesis, ovarian activation, aggression and alters sterility signal production in bumble bee (Bombus terrestris) workers

    USDA-ARS?s Scientific Manuscript database

    Juvenile hormone (JH) is an important regulator of development and physiology in insects. While in many insect species, including bumble bees, JH function as gonadotropin in adults, in some highly eusocial insects its role has shifted to regulate social behavior including division of labor, dominanc...

  8. USBombus, a database of contemporary survey data for North American Bumble Bees (Hymenoptera, Apidae, Bombus) distributed in the United States

    USDA-ARS?s Scientific Manuscript database

    This paper describes USBombus, a large dataset that represents the outcomes of one of the largest standardized surveys of bee pollinators (Hymenoptera, Apidae, Bombus) globally. The motivation to collect live bumble bees across the US was to examine the decline and conservation status of Bombus affi...

  9. Detoxification and stress response genes expressed in a western North American bumble bee, Bombus huntii (Hymenoptera: Apidae)

    PubMed Central

    2013-01-01

    Background The Hunt bumble bee (Bombus huntii Greene, Hymenoptera: Apidae) is a holometabolous, social insect important as a pollinator in natural and agricultural ecosystems in western North America. Bumble bees spend a significant amount of time foraging on a wide variety of flowering plants, and this activity exposes them to both plant toxins and pesticides, posing a threat to individual and colony survival. Little is known about what detoxification pathways are active in bumble bees, how the expression of detoxification genes changes across life stages, or how the number of detoxification genes expressed in B. huntii compares to other insects. Results We found B. huntii expressed at least 584 genes associated with detoxification and stress responses. The expression levels of some of these genes, such as those encoding the cytochrome P450s, glutathione S-transferases (GSTs) and glycosidases, vary among different life stages to a greater extent than do other genes. We also found that the number of P450s, GSTs and esterase genes expressed by B. huntii is similar to the number of these genes found in the genomes of other bees, namely Bombus terrestris, Bombus impatiens, Apis mellifera and Megachile rotundata, but many fewer than are found in the fly Drosophila melanogaster. Conclusions Bombus huntii has transcripts for a large number of detoxification and stress related proteins, including oxidation and reduction enzymes, conjugation enzymes, hydrolytic enzymes, ABC transporters, cadherins, and heat shock proteins. The diversity of genes expressed within some detoxification pathways varies among the life stages and castes, and we typically identified more genes in the adult females than in larvae, pupae, or adult males, for most pathways. Meanwhile, we found the numbers of detoxification and stress genes expressed by B. huntii to be more similar to other bees than to the fruit fly. The low number of detoxification genes, first noted in the honey bee, appears to be

  10. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris)

    PubMed Central

    Moffat, Christopher; Pacheco, Joao Goncalves; Sharp, Sheila; Samson, Andrew J.; Bollan, Karen A.; Huang, Jeffrey; Buckland, Stephen T.; Connolly, Christopher N.

    2015-01-01

    The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombus terrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2 days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization in neurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies.—Moffat, C., Pacheco, J. G., Sharp, S., Samson, A. J., Bollan, K. A., Huang, J., Buckland, S. T., Connolly, C. N. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris). PMID:25634958

  11. Differential expression pattern of Vago in bumblebee (Bombus terrestris), induced by virulent and avirulent virus infections.

    PubMed

    Niu, Jinzhi; Meeus, Ivan; Smagghe, Guy

    2016-09-29

    Viruses are one of the main drivers of the decline of domesticated and wild bees but the mechanisms of antiviral immunity in pollinators are poorly understood. Recent work has suggested that next to the small interfering RNA (siRNA) pathway other immune-related pathways play a role in the defense of the bee hosts against viral infection. In addition, Vago plays a role in the cross-talk between the innate immune pathways in Culex mosquito cells. Here we describe the Vago orthologue in bumblebees of Bombus terrestris, and investigated its role upon the infection of two different bee viruses, the virulent Israeli acute paralysis virus (IAPV) and the avirulent slow bee paralysis virus (SBPV). Our results showed that BtVago was downregulated upon the infection of IAPV that killed all bumblebees, but not with SBPV where the workers survived the virus infection. Thus, for the first time, Vago/Vago-like expression appears to be associated with the virulence of virus and may act as a modulator of antiviral immunity.

  12. Differential expression pattern of Vago in bumblebee (Bombus terrestris), induced by virulent and avirulent virus infections

    PubMed Central

    Niu, Jinzhi; Meeus, Ivan; Smagghe, Guy

    2016-01-01

    Viruses are one of the main drivers of the decline of domesticated and wild bees but the mechanisms of antiviral immunity in pollinators are poorly understood. Recent work has suggested that next to the small interfering RNA (siRNA) pathway other immune-related pathways play a role in the defense of the bee hosts against viral infection. In addition, Vago plays a role in the cross-talk between the innate immune pathways in Culex mosquito cells. Here we describe the Vago orthologue in bumblebees of Bombus terrestris, and investigated its role upon the infection of two different bee viruses, the virulent Israeli acute paralysis virus (IAPV) and the avirulent slow bee paralysis virus (SBPV). Our results showed that BtVago was downregulated upon the infection of IAPV that killed all bumblebees, but not with SBPV where the workers survived the virus infection. Thus, for the first time, Vago/Vago-like expression appears to be associated with the virulence of virus and may act as a modulator of antiviral immunity. PMID:27680717

  13. Patterns of range-wide genetic variation in six North American bumble bee (Apidae: Bombus) species.

    PubMed

    Lozier, Jeffrey D; Strange, James P; Stewart, Isaac J; Cameron, Sydney A

    2011-12-01

    The increasing evidence for population declines in bumble bee (Bombus) species worldwide has accelerated research efforts to explain losses in these important pollinators. In North America, a number of once widespread Bombus species have suffered serious reductions in range and abundance, although other species remain healthy. To examine whether declining and stable species exhibit different levels of genetic diversity or population fragmentation, we used microsatellite markers to genotype populations sampled across the geographic distributions of two declining (Bombus occidentalis and Bombus pensylvanicus) and four stable (Bombus bifarius; Bombus vosnesenskii; Bombus impatiens and Bombus bimaculatus) Bombus species. Populations of declining species generally have reduced levels of genetic diversity throughout their range compared to codistributed stable species. Genetic diversity can be affected by overall range size and degree of isolation of local populations, potentially confounding comparisons among species in some cases. We find no evidence for consistent differences in gene flow among stable and declining species, with all species exhibiting weak genetic differentiation over large distances (e.g. >1000 km). Populations on islands and at high elevations experience relatively strong genetic drift, suggesting that some conditions lead to genetic isolation in otherwise weakly differentiated species. B. occidentalis and B. bifarius exhibit stronger genetic differentiation than the other species, indicating greater phylogeographic structure consistent with their broader geographic distributions across topographically complex regions of western North America. Screening genetic diversity in North American Bombus should prove useful for identifying species that warrant monitoring, and developing management strategies that promote high levels of gene flow will be a key component in efforts to maintain healthy populations. © 2011 Blackwell Publishing Ltd.

  14. Landscape heterogeneity predicts gene flow in a widespread polymorphic bumble bee, Bombus bifarius (Hymentoptera: Apidae).

    USDA-ARS?s Scientific Manuscript database

    Bombus bifarius is a widespread bumble bee that occurs in montane regions of western North America. This species has several major color polymorphisms, and shows evidence of genetic structuring among regional populations. We test whether this structure is evidence for discrete gene flow barriers tha...

  15. Mechanosensory hairs in bumblebees (Bombus terrestris) detect weak electric fields

    PubMed Central

    Sutton, Gregory P.; Clarke, Dominic; Morley, Erica L.; Robert, Daniel

    2016-01-01

    Bumblebees (Bombus terrestris) use information from surrounding electric fields to make foraging decisions. Electroreception in air, a nonconductive medium, is a recently discovered sensory capacity of insects, yet the sensory mechanisms remain elusive. Here, we investigate two putative electric field sensors: antennae and mechanosensory hairs. Examining their mechanical and neural response, we show that electric fields cause deflections in both antennae and hairs. Hairs respond with a greater median velocity, displacement, and angular displacement than antennae. Extracellular recordings from the antennae do not show any electrophysiological correlates to these mechanical deflections. In contrast, hair deflections in response to an electric field elicited neural activity. Mechanical deflections of both hairs and antennae increase with the electric charge carried by the bumblebee. From this evidence, we conclude that sensory hairs are a site of electroreception in the bumblebee. PMID:27247399

  16. Mechanosensory hairs in bumblebees (Bombus terrestris) detect weak electric fields.

    PubMed

    Sutton, Gregory P; Clarke, Dominic; Morley, Erica L; Robert, Daniel

    2016-06-28

    Bumblebees (Bombus terrestris) use information from surrounding electric fields to make foraging decisions. Electroreception in air, a nonconductive medium, is a recently discovered sensory capacity of insects, yet the sensory mechanisms remain elusive. Here, we investigate two putative electric field sensors: antennae and mechanosensory hairs. Examining their mechanical and neural response, we show that electric fields cause deflections in both antennae and hairs. Hairs respond with a greater median velocity, displacement, and angular displacement than antennae. Extracellular recordings from the antennae do not show any electrophysiological correlates to these mechanical deflections. In contrast, hair deflections in response to an electric field elicited neural activity. Mechanical deflections of both hairs and antennae increase with the electric charge carried by the bumblebee. From this evidence, we conclude that sensory hairs are a site of electroreception in the bumblebee.

  17. Colonies of Bumble Bees (Bombus impatiens) Produce Fewer Workers, Less Bee Biomass, and Have Smaller Mother Queens Following Fungicide Exposure

    PubMed Central

    Bernauer, Olivia M.; Gaines-Day, Hannah R.; Steffan, Shawn A.

    2015-01-01

    Bees provide vital pollination services to the majority of flowering plants in both natural and agricultural systems. Unfortunately, both native and managed bee populations are experiencing declines, threatening the persistence of these plants and crops. Agricultural chemicals are one possible culprit contributing to bee declines. Even fungicides, generally considered safe for bees, have been shown to disrupt honey bee development and impair bumble bee behavior. Little is known, however, how fungicides may affect bumble bee colony growth. We conducted a controlled cage study to determine the effects of fungicide exposure on colonies of a native bumble bee species (Bombus impatiens). Colonies of B. impatiens were exposed to flowers treated with field-relevant levels of the fungicide chlorothalonil over the course of one month. Colony success was assessed by the number and biomass of larvae, pupae, and adult bumble bees. Bumble bee colonies exposed to fungicide produced fewer workers, lower total bee biomass, and had lighter mother queens than control colonies. Our results suggest that fungicides negatively affect the colony success of a native bumble bee species and that the use of fungicides during bloom has the potential to severely impact the success of native bumble bee populations foraging in agroecosystems. PMID:26463198

  18. Colonies of Bumble Bees (Bombus impatiens) Produce Fewer Workers, Less Bee Biomass, and Have Smaller Mother Queens Following Fungicide Exposure.

    PubMed

    Bernauer, Olivia M; Gaines-Day, Hannah R; Steffan, Shawn A

    2015-06-01

    Bees provide vital pollination services to the majority of flowering plants in both natural and agricultural systems. Unfortunately, both native and managed bee populations are experiencing declines, threatening the persistence of these plants and crops. Agricultural chemicals are one possible culprit contributing to bee declines. Even fungicides, generally considered safe for bees, have been shown to disrupt honey bee development and impair bumble bee behavior. Little is known, however, how fungicides may affect bumble bee colony growth. We conducted a controlled cage study to determine the effects of fungicide exposure on colonies of a native bumble bee species (Bombus impatiens). Colonies of B. impatiens were exposed to flowers treated with field-relevant levels of the fungicide chlorothalonil over the course of one month. Colony success was assessed by the number and biomass of larvae, pupae, and adult bumble bees. Bumble bee colonies exposed to fungicide produced fewer workers, lower total bee biomass, and had lighter mother queens than control colonies. Our results suggest that fungicides negatively affect the colony success of a native bumble bee species and that the use of fungicides during bloom has the potential to severely impact the success of native bumble bee populations foraging in agroecosystems.

  19. Structural Analysis of Hand Drawn Bumblebee Bombus terrestris Silk.

    PubMed

    Woodhead, Andrea L; Sutherland, Tara D; Church, Jeffrey S

    2016-07-20

    Bombus terrestris, commonly known as the buff-tailed bumblebee, is native to Europe, parts of Africa and Asia. It is commercially bred for use as a pollinator of greenhouse crops. Larvae pupate within a silken cocoon that they construct from proteins produced in modified salivary glands. The amino acid composition and protein structure of hand drawn B. terrestris, silk fibres was investigated through the use of micro-Raman spectroscopy. Spectra were obtained from single fibres drawn from the larvae salivary gland at a rate of 0.14 cm/s. Raman spectroscopy enabled the identification of poly(alanine), poly(alanine-glycine), phenylalanine, tryptophan, and methionine, which is consistent with the results of amino acid analysis. The dominant protein conformation was found to be coiled coil (73%) while the β-sheet content of 10% is, as expected, lower than those reported for hornets and ants. Polarized Raman spectra revealed that the coiled coils were highly aligned along the fibre axis while the β-sheet and random coil components had their peptide carbonyl groups roughly perpendicular to the fibre axis. The protein orientation distribution is compared to those of other natural and recombinant silks. A structural model for the B. terrestris silk fibre is proposed based on these results.

  20. Structural Analysis of Hand Drawn Bumblebee Bombus terrestris Silk

    PubMed Central

    Woodhead, Andrea L.; Sutherland, Tara D.; Church, Jeffrey S.

    2016-01-01

    Bombus terrestris, commonly known as the buff-tailed bumblebee, is native to Europe, parts of Africa and Asia. It is commercially bred for use as a pollinator of greenhouse crops. Larvae pupate within a silken cocoon that they construct from proteins produced in modified salivary glands. The amino acid composition and protein structure of hand drawn B. terrestris, silk fibres was investigated through the use of micro-Raman spectroscopy. Spectra were obtained from single fibres drawn from the larvae salivary gland at a rate of 0.14 cm/s. Raman spectroscopy enabled the identification of poly(alanine), poly(alanine-glycine), phenylalanine, tryptophan, and methionine, which is consistent with the results of amino acid analysis. The dominant protein conformation was found to be coiled coil (73%) while the β-sheet content of 10% is, as expected, lower than those reported for hornets and ants. Polarized Raman spectra revealed that the coiled coils were highly aligned along the fibre axis while the β-sheet and random coil components had their peptide carbonyl groups roughly perpendicular to the fibre axis. The protein orientation distribution is compared to those of other natural and recombinant silks. A structural model for the B. terrestris silk fibre is proposed based on these results. PMID:27447623

  1. Analysis of pollen and nectar of Arbutus unedo as a food source for Bombus terrestris (Hymenoptera: Apidae).

    PubMed

    Rasmont, Pierre; Regali, Ariane; Ings, Thomas C; Lognay, Georges; Baudart, Evelyne; Marlier, Michel; Delcarte, Emile; Viville, Pascal; Marot, Cécile; Falmagne, Pol; Verhaeghe, Jean-Claude; Chittka, Lars

    2005-06-01

    The mineral, total amino acid, and sterol compositions of pollen collected by Apis mellifera L. were compared with the pollen of a plant consumed by Bombus terrestris (L.): Arbutus unedo L. This plant provides the predominant food resource for the main autumn generation of B. terrestris in southern France. Honey bees also forage on this plant, although only for nectar. The mineral composition of 30 pollen samples collected by honey bees is close to the presently known requirements of A. mellifera, except for Cu and Mn, which are substantially lower. The total amino acid mean composition of a set of 54 pollen samples fits the basic requirements of honey bees except for valine, isoleucine, and methionine, which are present in lower concentrations in all the samples. For pollen of A. unedo, the amino acid balance is not very different from that of the survey. The main sterolic component in pollen of A. unedo, beta-sitosterol, is known to have antifeedant effects on A. mellifera. Honey bees cannot dealkylate C29 sterols like beta-sitosterol or delta5-avenasterol to obtain C27 cholesterol and ecdysteroids. Because these phytosterols as well as cholesterol are nearly absent from pollen of A. unedo, the metabolic capabilities of Apis seem unadapted to this plant. On the contrary, pollen of A. unedo is freely consumed by B. terrestris, which develops huge autumn populations solely on this food. These data indicate that the sterolic metabolisms of B. terrestris and A. mellifera differ, allowing separation in foraging activity.

  2. Fertility signals in the bumblebee Bombus terrestris (Hymenoptera: Apidae)

    NASA Astrophysics Data System (ADS)

    Sramkova, A.; Schulz, C.; Twele, R.; Francke, W.; Ayasse, M.

    2008-06-01

    In eusocial Hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. In primitively eusocial bumblebees ( Bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. Furthermore, it was shown that the queen dominance is maintained by pheromonal cues. We investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a fertility signal. We collected cuticular surface extracts from nest-searching and breeding Bombus terrestris queens and workers that were characterized by their ovarian stages. In chemical analyses, we identified 61 compounds consisting of aldehydes, alkanes, alkenes, and fatty acid esters. Nest-searching queens and all groups of breeding females differed significantly in their odor bouquets. Furthermore, workers before the competition point (time point of colony development where workers start to develop ovaries and lay eggs) differed largely from queens and all other groups of workers. Breeding queens showed a unique bouquet of chemical compounds and certain queen-specific compounds, and the differences toward workers decrease with an increasing development of the workers’ ovaries, hinting the presence of a reliable fertility signal. Among the worker groups, the smallest differences were found after the competition point. Egg-laying females contained higher total amounts of chemical compounds and of relative proportions of wax-type esters and aldehydes than nest-searching queens and workers before the competition point. Therefore, these compounds may have a function as a fertility signal present in queens and workers.

  3. A scientific note on Bombus (Psithyrus) insularis invasions of bumble bee nests and honey bee hives in the western United States

    USDA-ARS?s Scientific Manuscript database

    Bumble bees (genus Bombus) are critical pollinators of flowering plants, yet some species are obligate social parasites that do little pollinating and reduce the fitness of the colonies they invade. In 2012 we observed an outbreak of the parasitic Bombus insularis in the Cache Valley of Northern Ut...

  4. Daily changes in ultraviolet light levels can synchronize the circadian clock of bumblebees (Bombus terrestris).

    PubMed

    Chittka, Lars; Stelzer, Ralph J; Stanewsky, Ralf

    2013-05-01

    Endogenous circadian clocks are synchronized to the 24-h day by external zeitgebers such as daily light and temperature cycles. Bumblebee foragers show diurnal rhythms under daily light:dark cycles and short-period free-running circadian rhythms in constant light conditions in the laboratory. In contrast, during the continuous light conditions of the arctic summer, they show robust 24-h rhythms in their foraging patterns, meaning that some external zeitgeber must entrain their circadian clocks in the presence of constant light. Although the sun stays above the horizon for weeks during the arctic summer, the light quality, especially in the ultraviolet (UV) range, exhibits pronounced daily changes. Since the photoreceptors and photopigments that synchronize the circadian system of bees are not known, we tested if the circadian clocks of bumblebees (Bombus terrestris) can be entrained by daily cycles in UV light levels. Bumblebee colonies were set up in the laboratory and exposed to 12 h:12 h UV + :UV- cycles in otherwise continuous lighting conditions by placing UV filters on their foraging arenas for 12 h each day. The activity patterns of individual bees were recorded using fully automatic radiofrequency identification (RFID). We found that colonies manipulated in such a way showed synchronized 24-h rhythms, whereas simultaneously tested control colonies with no variation in UV light levels showed free-running rhythms instead. The results of our study show that bumblebee circadian rhythms can indeed be synchronized by daily cycles in ambient light spectral composition.

  5. Bumblebees (Bombus terrestris) use social information as an indicator of safety in dangerous environments

    PubMed Central

    Dawson, Erika H.; Chittka, Lars

    2014-01-01

    Avoiding predation is one of the most important challenges that an animal faces. Several anti-predation behaviours can be employed, yet simply using the presence of conspecifics can be a good signal of safety in an environment with potential predation hazards. Here, we show, for the first time, that past experience of predation causes bumblebees (Bombus terrestris) to aggregate with conspecifics, facilitating the identification of safe foraging patches. Bees were trained to differentiate between flowers that harboured predators and flowers that were predator free. When test subjects were subsequently presented solely with the previously predator-infested flower species, there was a significant preference to only land on flowers occupied by other feeding conspecifics. Yet, when safe flowers were made available to subjects previously entrained to discriminate safe from predator-occupied flowers, subjects ignored other bees and the social information potentially provided by them, demonstrating that attraction towards conspecifics is confined to dangerous situations. Our findings demonstrate a previously unknown social interaction in pollinators which may have important implications for plant–pollinator interactions. PMID:24789891

  6. Leg tendon glands in male bumblebees ( Bombus terrestris): structure, secretion chemistry, and possible functions

    NASA Astrophysics Data System (ADS)

    Jarau, Stefan; Žáček, Petr; Šobotník, Jan; Vrkoslav, Vladimír; Hadravová, Romana; Coppée, Audrey; Vašíčková, Soňa; Jiroš, Pavel; Valterová, Irena

    2012-12-01

    Among the large number of exocrine glands described in bees, the tarsal glands were thought to be the source of footprint scent marks. However, recent studies showed that the compounds used for marking by stingless bees are secreted by leg tendon instead of tarsal glands. Here, we report on the structure of leg tendon glands in males of Bombus terrestris, together with a description of the chemical composition of their secretions and respective changes of both during the males' lives. The ultrastructure of leg tendon glands shows that the secretory cells are located in three independent regions, separated from each other by unmodified epidermal cells: in the femur, tibia, and basitarsus. Due to the common site of secretion release, the organ is considered a single secretory gland. The secretion of the leg tendon glands of B. terrestris males differs in its composition from those of workers and queens, in particular by (1) having larger proportions of compounds with longer chain lengths, which we identified as wax esters; and (2) by the lack of certain hydrocarbons (especially long chain dienes). Other differences consist in the distribution of double bond positions in the unsaturated hydrocarbons that are predominantly located at position 9 in males but distributed at seven to nine different positions in the female castes. Double bond positions may change chemical and physical properties of a molecule, which can be recognized by the insects and, thus, may serve to convey specific information. The function of male-specific compounds identified from their tendon glands remains elusive, but several possibilities are discussed.

  7. Interspecific mating of the introduced bumblebee Bombus terrestris and the native Japanese bumblebee Bombus hypocrita sapporoensis results in inviable hybrids

    NASA Astrophysics Data System (ADS)

    Kanbe, Yuya; Okada, Ikuko; Yoneda, Masahiro; Goka, Koichi; Tsuchida, Koji

    2008-10-01

    The bumblebee Bombus terrestris is not only an effective pollinator, but also a potential invasive alien species outside its native range. Recently, nearly 30% of queens of the Japanese native species Bombus hypocrita sapporoensis and B. hypocrita hypocrita were estimated to copulate with B. terrestris males in the field, suggesting that indigenous bumblebees could be genetically deteriorated through hybrid production with the introduced species. In this study, we evaluated hybrid production between the introduced B. terrestris and the indigenous B. hypocrita sapporoensis under laboratory conditions. The hatching rate of eggs derived from interspecific matings was 0% and 8.6% depending on the direction of the cross, which was significantly lower than that from intraspecific matings of B. terrestris (76.9%) and B. hypocrita sapporoensis (78.9%). Genetic studies using microsatellite markers revealed that both haploid and diploid individuals were present in the egg stage, whereas all hatched larvae were haploid. In addition, histological studies revealed that eggs derived from interspecific matings terminated development 2 days after oviposition. These results strongly suggested that eggs derived from interspecific matings are inviable due to post-mating isolation mechanisms. Mass release of exotic pollinators could cause serious population declines of native bumblebee species.

  8. Bumble Bees (Hymenoptera: Apidae: Bombus spp.) of Interior Alaska: Species Composition, Distribution, Seasonal Biology, and Parasites

    PubMed Central

    Pampell, Rehanon; Pantoja, Alberto; Holloway, Patricia; Knight, Charles; Ranft, Richard

    2015-01-01

    Abstract Background Despite the ecological and agricultural significance of bumble bees in Alaska, very little is known and published about this important group at the regional level. The objectives of this study were to provide baseline data on species composition, distribution, seasonal biology, and parasites of the genus Bombus at three major agricultural locations within Alaska: Fairbanks, Delta Junction, and Palmer, to lay the groundwork for future research on bumble bee pollination in Alaska. New information A total of 8,250 bumble bees representing 18 species was collected from agricultural settings near Delta Junction, Fairbanks, and Palmer, Alaska in 2009 and 2010. Of the 8,250 specimens, 51% were queens, 32.7% were workers, and 16.2% were males. The species composition and relative abundances varied among sites and years. Delta Junction had the highest relative abundance of bumble bees, representing 51.6% of the specimens collected; the other two locations, Fairbanks and Palmer represented 26.5% and 21.8% of the overall catch respectively. The species collected were: Bombus bohemicus Seidl 1837 (= B. ashtoni (Cresson 1864)), B. balteatus Dahlbom 1832, B. bifarius Cresson 1878, B. centralis Cresson 1864, B. cryptarum (Fabricius 1775) (=B. moderatus Cresson 1863), B. distinguendus Morawitz 1869, B. flavidus Eversmann 1852 (=B. fernaldae Franklin 1911), B. flavifrons Cresson 1863, B. frigidus Smith 1854, B. insularis (Smith 1861), B. jonellus (Kirby 1802), B. melanopygus Nylander 1848, B. mixtus Cresson 1878, B. neoboreus Sladen 1919, B. occidentalis Greene 1858, B. perplexus Cresson 1863, B. rufocinctus Cresson 1863, and B. sylvicola Kirby 1837. Overall, the most common bumble bees near agricultural lands were B. centralis, B. frigidus, B. jonellus, B. melanopygus, B. mixtus, and B. occidentalis. Species' relative population densities and local diversity were highly variable from year to year. Bombus occidentalis, believed to be in decline in the Pacific

  9. Bumble Bees (Bombus spp) along a Gradient of Increasing Urbanization

    PubMed Central

    Ahrné, Karin; Bengtsson, Jan; Elmqvist, Thomas

    2009-01-01

    Background Bumble bees and other wild bees are important pollinators of wild flowers and several cultivated crop plants, and have declined in diversity and abundance during the last decades. The main cause of the decline is believed to be habitat destruction and fragmentation associated with urbanization and agricultural intensification. Urbanization is a process that involves dramatic and persistent changes of the landscape, increasing the amount of built-up areas while decreasing the amount of green areas. However, urban green areas can also provide suitable alternative habitats for wild bees. Methodology/Principal Findings We studied bumble bees in allotment gardens, i.e. intensively managed flower rich green areas, along a gradient of urbanization from the inner city of Stockholm towards more rural (periurban) areas. Keeping habitat quality similar along the urbanization gradient allowed us to separate the effect of landscape change (e.g. proportion impervious surface) from variation in habitat quality. Bumble bee diversity (after rarefaction to 25 individuals) decreased with increasing urbanization, from around eight species on sites in more rural areas to between five and six species in urban allotment gardens. Bumble bee abundance and species composition were most affected by qualities related to the management of the allotment areas, such as local flower abundance. The variability in bumble bee visits between allotment gardens was higher in an urban than in a periurban context, particularly among small and long-tongued bumble bee species. Conclusions/Significance Our results suggest that allotment gardens and other urban green areas can serve as important alternatives to natural habitats for many bumble bee species, but that the surrounding urban landscape influences how many species that will be present. The higher variability in abundance of certain species in the most urban areas may indicate a weaker reliability of the ecosystem service pollination in

  10. Bumble bees (Bombus spp) along a gradient of increasing urbanization.

    PubMed

    Ahrné, Karin; Bengtsson, Jan; Elmqvist, Thomas

    2009-01-01

    Bumble bees and other wild bees are important pollinators of wild flowers and several cultivated crop plants, and have declined in diversity and abundance during the last decades. The main cause of the decline is believed to be habitat destruction and fragmentation associated with urbanization and agricultural intensification. Urbanization is a process that involves dramatic and persistent changes of the landscape, increasing the amount of built-up areas while decreasing the amount of green areas. However, urban green areas can also provide suitable alternative habitats for wild bees. We studied bumble bees in allotment gardens, i.e. intensively managed flower rich green areas, along a gradient of urbanization from the inner city of Stockholm towards more rural (periurban) areas. Keeping habitat quality similar along the urbanization gradient allowed us to separate the effect of landscape change (e.g. proportion impervious surface) from variation in habitat quality. Bumble bee diversity (after rarefaction to 25 individuals) decreased with increasing urbanization, from around eight species on sites in more rural areas to between five and six species in urban allotment gardens. Bumble bee abundance and species composition were most affected by qualities related to the management of the allotment areas, such as local flower abundance. The variability in bumble bee visits between allotment gardens was higher in an urban than in a periurban context, particularly among small and long-tongued bumble bee species. Our results suggest that allotment gardens and other urban green areas can serve as important alternatives to natural habitats for many bumble bee species, but that the surrounding urban landscape influences how many species that will be present. The higher variability in abundance of certain species in the most urban areas may indicate a weaker reliability of the ecosystem service pollination in areas strongly influenced by human activity.

  11. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris).

    PubMed

    Moffat, Christopher; Pacheco, Joao Goncalves; Sharp, Sheila; Samson, Andrew J; Bollan, Karen A; Huang, Jeffrey; Buckland, Stephen T; Connolly, Christopher N

    2015-05-01

    The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombus terrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2 days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization in neurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies.

  12. Pollen foraging: learning a complex motor skill by bumblebees (Bombus terrestris)

    NASA Astrophysics Data System (ADS)

    Raine, Nigel E.; Chittka, Lars

    2007-06-01

    To investigate how bumblebees (Bombus terrestris) learn the complex motor skills involved in pollen foraging, we observed naïve workers foraging on arrays of nectarless poppy flowers (Papaver rhoeas) in a greenhouse. Foraging skills were quantified by measuring the pollen load collected during each foraging bout and relating this to the number of flowers visited and bout duration on two consecutive days. The pollen standing crop (PSC) in each flower decreased drastically from 0530 to 0900 hours. Therefore, we related foraging performance to the changing levels of pollen available (per flower) and found that collection rate increased over the course of four consecutive foraging bouts (comprising between 277 and 354 individual flower visits), suggesting that learning to forage for pollen represents a substantial time investment for individual foragers. The pollen collection rate and size of pollen loads collected at the start of day 2 were markedly lower than at the end of day 1, suggesting that components of pollen foraging behaviour could be subject to imperfect overnight retention. Our results suggest that learning the necessary motor skills to collect pollen effectively from morphologically simple flowers takes three times as many visits as learning how to handle the most morphologically complex flowers to extract nectar, potentially explaining why bees are more specialised in their choice of pollen flowers.

  13. Lethal and sub-lethal effects of spinosad on bumble bees (Bombus impatiens Cresson).

    PubMed

    Morandin, Lora A; Winston, Mark L; Franklin, Michelle T; Abbott, Virginia A

    2005-07-01

    Recent developments of new families of pesticides and growing awareness of the importance of wild pollinators for crop pollination have stimulated interest in potential effects of novel pesticides on wild bees. Yet pesticide toxicity studies on wild bees remain rare, and few studies have included long-term monitoring of bumble bee colonies or testing of foraging ability after pesticide exposure. Larval bees feeding on exogenous pollen and exposed to pesticides during development may result in lethal or sub-lethal effects during the adult stage. We tested the effects of a naturally derived biopesticide, spinosad, on bumble bee (Bombus impatiens Cresson) colony health, including adult mortality, brood development, weights of emerging bees and foraging efficiency of adults that underwent larval development during exposure to spinosad. We monitored colonies from an early stage, over a 10-week period, and fed spinosad to colonies in pollen at four levels: control, 0.2, 0.8 and 8.0 mg kg(-1), during weeks 2 through 5 of the experiment. At concentrations that bees would likely encounter in pollen in the wild (0.2-0.8 mg kg(-1)) we detected minimal negative effects to bumble bee colonies. Brood and adult mortality was high at 8.0 mg kg(-1) spinosad, about twice the level that bees would be exposed to in a 'worst case' field scenario, resulting in colony death two to four weeks after initial pesticide exposure. At more realistic concentrations there were potentially important sub-lethal effects. Adult worker bees exposed to spinosad during larval development at 0.8 mg kg(-1) were slower foragers on artificial complex flower arrays than bees from low or no spinosad treated colonies. Inclusion of similar sub-lethal assays to detect effects of pesticides on pollinators would aid in development of environmentally responsible pest management strategies.

  14. Colony contact contributes to the diversity of gut bacteria in bumblebees (Bombus terrestris).

    PubMed

    Billiet, Annelies; Meeus, Ivan; Van Nieuwerburgh, Filip; Deforce, Dieter; Wäckers, Felix; Smagghe, Guy

    2017-04-01

    Social bees, like honeybees and bumblebees, have a close contact with nest mates of different developmental stages and generations. This could enhance bacterial transfer between nest mates and offers opportunities for direct transfer of symbionts from one generation to the next, resulting in a stable host specific gut microbiota. Gut symbionts of honeybees and bumblebees have been suggested to contribute in digestion and protection against parasites and pathogens. Here we studied the impact of contact with the bumblebee colony on the colonization potential of the bacterial families (i.e., Neisseriaceae, Orbaceae, Lactobacillaceae and Bifidobacteriaceae) occurring in the gut of adult bumblebees (Bombus terrestris). Bacterial profiles of the gut microbiota of B. terrestris were determined based on the hypervariable V4 region of the 16S rRNA using paired-end Illumina sequencing. In our experiments, we created different groups in which we gradually reduced the contact with nest mates and hive material. We made 3 observations: (i) reducing the contact between the colony and the bumblebee during adult life resulted in a significant drop in the relative abundance of Lactobacillus bombicola and Lactobacillus bombi; (ii) Bifidobacteriaceae required contact with nest mates to colonize the gut of B. terrestris and a significant lower bacterial diversity was observed in bumblebees that were completely excluded from colony contact during the adult life; (iii) Snodgrassella and Gilliamella were able to colonize the gut of the adult bumblebee without any direct contact with nest mates in the adult life stage. These results indicate the impact of the colony life on the diversity of the characteristic bumblebee gut bacteria. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  15. The Adaptive Significance of Sensory Bias in a Foraging Context: Floral Colour Preferences in the Bumblebee Bombus terrestris

    PubMed Central

    Raine, Nigel E.; Chittka, Lars

    2007-01-01

    Innate sensory biases could play an important role in helping naïve animals to find food. As inexperienced bees are known to have strong innate colour biases we investigated whether bumblebee (Bombus terrestris) colonies with stronger biases for the most rewarding flower colour (violet) foraged more successfully in their local flora. To test the adaptive significance of variation in innate colour bias, we compared the performance of colour-naïve bees, from nine bumblebee colonies raised from local wild-caught queens, in a laboratory colour bias paradigm using violet (bee UV-blue) and blue (bee blue) artificial flowers. The foraging performance of the same colonies was assessed under field conditions. Colonies with a stronger innate bias for violet over blue flowers in the laboratory harvested more nectar per unit time under field conditions. In fact, the colony with the strongest bias for violet (over blue) brought in 41% more nectar than the colony with the least strong bias. As violet flowers in the local area produce more nectar than blue flowers (the next most rewarding flower colour), these data are consistent with the hypothesis that local variation in flower traits could drive selection for innate colour biases. PMID:17579727

  16. Percent lipid is associated with body size but not task in the bumble bee Bombus impatiens

    PubMed Central

    Jandt, Jennifer M.; Bonds, Jennifer; Helm, Bryan R.; Dornhaus, Anna

    2015-01-01

    In some group-living organisms, labor is divided among individuals. This allocation to particular tasks is frequently stable and predicted by individual physiology. Social insects are excellent model organisms in which to investigate the interplay between physiology and individual behavior, as division of labor is an important feature within colonies, and individual physiology varies among the highly related individuals of the colony. Previous studies have investigated what factors are important in determining how likely an individual is, compared to nest-mates, to perform certain tasks. One such task is foraging. Corpulence (i.e., percent lipid) has been shown to determine foraging propensity in honey bees and ants, with leaner individuals being more likely to be foragers. Is this a general trend across all social insects? Here we report data analyzing the individual physiology, specifically the percent lipid, of worker bumble bees (Bombus impatiens) from whom we also analyze behavioral task data. Bumble bees are also unusual among the social bees in that workers may vary widely in size. Surprisingly we find that, unlike other social insects, percent lipid is not associated with task propensity. Rather, body size closely predicts individual relative lipid stores, with smaller worker bees being allometrically fatter than larger worker bees. PMID:21847618

  17. Survey of bumble bee (Bombus) pathogens and parasites in Illinois and selected areas of northern California and southern Oregon.

    PubMed

    Kissinger, Christina N; Cameron, Sydney A; Thorp, Robbin W; White, Brendan; Solter, Leellen F

    2011-07-01

    Pathogens have been implicated as potential factors in the recent decline of some North American bumble bee (Bombus) species, but little information has been reported about the natural enemy complex of bumble bees in the United States. We targeted bumble bee populations in a state-wide survey in Illinois and several sites in California and Oregon where declines have been reported to determine presence and prevalence of natural enemies. Based on our observations, most parasites and pathogens appear to be widespread generalists among bumble bee species, but susceptibility to some natural enemies appeared to vary. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Nest Initiation in Three North American Bumble Bees (Bombus): Gyne Number and Presence of Honey Bee Workers Influence Establishment Success and Colony Size

    PubMed Central

    Strange, James P.

    2010-01-01

    Three species of bumble bees, Bombus appositus Cresson, Bombus bifarius, Cresson and Bombus centralis Cresson (Hymenoptera: Apidae) were evaluated for nest initiation success under three sets of initial conditions. In the spring, gynes of each species were caught in the wild and introduced to nest boxes in one of three ways. Gynes were either introduced in conspecific pairs, singly with two honey bees, Apis mellifera L. (Hymenoptera: Apidae) workers, or alone. Nesting success and colony growth parameters were measured to understand the effects of the various treatments on nest establishment. Colonies initiated from pairs of conspecific gynes were most successful in producing worker bees (59.1%), less successful were colonies initiated with honey bee workers (33.3%), and least successful were bumble bee gynes initiating colonies alone (16.7%). There was a negative correlation between the numbers of days to the emergence of the first worker in a colony to the attainment of ultimate colony size, indicating that gynes that have not commenced oviposition in 21 days are unlikely to result in colonies exceeding 50 workers. B. appositus had the highest rate of nest establishment followed by B. bifarius and B. centralis. Nest establishment rates in three western bumble bee species can be increased dramatically by the addition of either honey bee workers or a second gyne to nesting boxes at colony initiation. PMID:20879924

  19. Observational Conditioning in Flower Choice Copying by Bumblebees (Bombus terrestris): Influence of Observer Distance and Demonstrator Movement

    PubMed Central

    Avarguès-Weber, Aurore; Chittka, Lars

    2014-01-01

    Background Bumblebees use information provided inadvertently by conspecifics when deciding between different flower foraging options. Such social learning might be explained by relatively simple associative learning mechanism: the bee may learn to associate conspecifics with nectar or pollen reward through previous experience of foraging jointly. However, in some studies, observers were guided by choices of ‘demonstrators’ viewed through a screen, so no reward was given to the observers at the time of seeing other bees’ flowers choice and no demonstrator bee was present at the moment of decision. This behaviour, referred to observational conditioning, implies an additional associative step as the positive value of conspecific is transferred to the associated flower. Here we explore the role of demonstrator movement, and the distance between observers and demonstrators that is required for observation conditioning to take place. Methodology/Principal Findings We identify the conditions under which observational conditioning occurs in the widespread European species Bombus terrestris. The presence of artificial demonstrator bees leads to a significant change in individual colour preference toward the indicated colour if demonstrators were moving and observation distance was limited (15 cm), suggesting that observational conditioning could only influence relatively short-range foraging decisions. In addition, the movement of demonstrators is a crucial factor for observational conditioning, either due to the more life-like appearance of moving artificial bees or an enhanced detectability of moving demonstrators, and an increased efficiency at directing attention to the indicated flower colour. Conclusion Bumblebees possess the capacity to learn the quality of a flower by distal observation of other foragers’ choices. This confirms that social learning in bees involves more advanced processes than simple associative learning, and indicates that observational

  20. Nutrient balancing of the adult worker bumblebee (Bombus terrestris) depends on the dietary source of essential amino acids

    PubMed Central

    Stabler, Daniel; Paoli, Pier P.; Nicolson, Susan W.; Wright, Geraldine A.

    2015-01-01

    ABSTRACT Animals carefully regulate the amount of protein that they consume. The quantity of individual essential amino acids (EAAs) obtained from dietary protein depends on the protein source, but how the proportion of EAAs in the diet affects nutrient balancing has rarely been studied. Recent research using the Geometric Framework for Nutrition has revealed that forager honeybees who receive much of their dietary EAAs from floral nectar and not from solid protein have relatively low requirements for dietary EAAs. Here, we examined the nutritional requirements for protein and carbohydrates of foragers of the buff-tailed bumblebee Bombus terrestris. By using protein (sodium caseinate) or an equimolar mixture of the 10 EAAs, we found that the intake target (nutritional optimum) of adult workers depended on the source and proportion of dietary EAAs. When bees consumed caseinate-containing diets in a range of ratios between 1:250 and 1:25 (protein to carbohydrate), they achieved an intake target (IT) of 1:149 (w/w). In contrast to those fed protein, bees fed the EAA diets had an IT more biased towards carbohydrates (1:560 w/w) but also had a greater risk of death than those fed caseinate. We also tested how the dietary source of EAAs affected free AAs in bee haemolymph. Bees fed diets near their IT had similar haemolymph AA profiles, whereas bees fed diets high in caseinate had elevated levels of leucine, threonine, valine and alanine in the haemolymph. We found that like honeybees, bumblebee workers prioritize carbohydrate intake and have a relatively low requirement for protein. The dietary source of EAAs influenced both the ratio of protein/EAA to carbohydrate and the overall amount of carbohydrate eaten. Our data support the idea that EAAs and carbohydrates in haemolymph are important determinants of nutritional state in insects. PMID:25617453

  1. Hazards of imidacloprid seed coating to Bombus terrestris (Hymenoptera: Apidae) when applied to sunflower.

    PubMed

    Tasei, J N; Ripault, G; Rivault, E

    2001-06-01

    Seed coating treatments of sunflower by the systemic insecticide imidacloprid was suspected of affecting honey bees and bumblebees. The hypothesis raised was whether imidacloprid could migrate into nectar and pollen, then modify flower attractiveness, homing behavior, and colony development. Our greenhouse and field experiments with Bombus terrestris L. were aimed at the following: the behavior of workers foraging on treated and control plants blooming in a greenhouse, the homing rate of colonies placed for 9 d in a treated field compared with colonies in a control field, and the development of these 20 colonies under laboratory conditions when removed from the fields. In the greenhouse, workers visited blooming heads of treated and control plants at the same rate and the mean duration of their visits was similar. In field colonies, analysis of pollen in hairs and pellets of workers showed that in both fields 98% of nectar foragers visited exclusively sunflowers, whereas only 25% of pollen gatherers collected sunflower pollen. After 9 d, in the control and treated field, 23 and 33% of the marked foragers, respectively, did not return to hives. In both fields, workers significantly drifted from the center to the sides of colony rows. During the 26-d period under field and laboratory conditions, the population increase rate of the 20 colonies was 3.3 and 3.0 workers/d in hives of the control and treated field, respectively. This difference was not significant. New queens were produced in eight colonies in either field. The mean number of new queens per hive was 17 and 24 in the control and treated field, respectively. Their mating rate was the same. It was concluded that applying imidacloprid at the registered dose, as a seed coating of sunflowers cultivated in greenhouse or in field, did not significantly affect the foraging and homing behavior of B. terestris and its colony development.

  2. Managed bumble bees (Bombus impatiens) (Hymenoptera: Apidae) caged with blueberry bushes at high density did not increase fruit set or fruit weight compared to open pollination

    Treesearch

    J. W. Campbell; J. O' Brien; J. H. Irvin; C. B. Kimmel; J. C. Daniels; J. D. Ellis

    2017-01-01

    Highbush blueberry (Vaccinium corymbosum L.) is an important crop grown throughout Florida. Currently, most blueberry growers use honey bees (Apis mellifera L.) to provide pollination services for highbush blueberries even though bumble bees (Bombus spp.) have been shown to be more efficient at pollinating blueberries on a per bee basis. In general, contribution of...

  3. Big city Bombus: using natural history and land-use history to find significant environmental drivers in bumble-bee declines in urban development

    PubMed Central

    Simao, Maria-Carolina; Vaidya, Chatura; Fitch, Gordon; Iulinao, Benjamin

    2017-01-01

    Native bee populations are critical sources of pollination. Unfortunately, native bees are declining in abundance and diversity. Much of this decline comes from human land-use change. While the effects of large-scale agriculture on native bees are relatively well understood, the effects of urban development are less clear. Understanding urbanity's effect on native bees requires consideration of specific characteristics of both particular bee species and their urban landscape. We surveyed bumble-bee (Bombus spp.) abundance and diversity in gardens across multiple urban centres in southeastern Michigan. There are significant declines in Bombus abundance and diversity associated with urban development when measured on scales in-line with Bombus flight ability. These declines are entirely driven by declines in females; males showed no response to urbanization. We hypothesize that this is owing to differing foraging strategies between the sexes, and it suggests reduced Bombus colony density in more urban areas. While urbanity reduced Bombus prevalence, results in Detroit imply that ‘shrinking cities’ potentially offer unique urban paradigms that must be considered when studying wild bee ecology. Results show previously unidentified differences in the effects of urbanity on female and male bumble-bee populations and suggest that urban landscapes can be managed to support native bee conservation. PMID:28573023

  4. Big city Bombus: using natural history and land-use history to find significant environmental drivers in bumble-bee declines in urban development.

    PubMed

    Glaum, Paul; Simao, Maria-Carolina; Vaidya, Chatura; Fitch, Gordon; Iulinao, Benjamin

    2017-05-01

    Native bee populations are critical sources of pollination. Unfortunately, native bees are declining in abundance and diversity. Much of this decline comes from human land-use change. While the effects of large-scale agriculture on native bees are relatively well understood, the effects of urban development are less clear. Understanding urbanity's effect on native bees requires consideration of specific characteristics of both particular bee species and their urban landscape. We surveyed bumble-bee (Bombus spp.) abundance and diversity in gardens across multiple urban centres in southeastern Michigan. There are significant declines in Bombus abundance and diversity associated with urban development when measured on scales in-line with Bombus flight ability. These declines are entirely driven by declines in females; males showed no response to urbanization. We hypothesize that this is owing to differing foraging strategies between the sexes, and it suggests reduced Bombus colony density in more urban areas. While urbanity reduced Bombus prevalence, results in Detroit imply that 'shrinking cities' potentially offer unique urban paradigms that must be considered when studying wild bee ecology. Results show previously unidentified differences in the effects of urbanity on female and male bumble-bee populations and suggest that urban landscapes can be managed to support native bee conservation.

  5. Evaluating the molecular, physiological and behavioral impacts of CO2 narcosis in bumble bees (Bombus impatiens).

    PubMed

    Amsalem, Etya; Grozinger, Christina M

    2017-08-01

    Exposure to carbon dioxide (CO2) has pleiotropic effects in many insect species, ranging from eliciting rapid behavioral responses such as attraction, to dramatic physiological changes, including ovary activation. In bumble bees, CO2 narcosis causes queens to bypass diapause and initiate egg laying, but its mode of action is not well-understood. Here, we evaluated the effects of CO2 narcosis on the behavior, physiology and immune function of virgin bumble bee queens (Bombus impatiens). We tested the hypothesis that CO2 induces these changes by stimulating oxidative stress response pathways. We found that CO2 stimulates ovarian activation and egg production and suppresses lipid (but not glycogen) accumulation in virgin queens. Additionally, CO2 treated queens were more active (particularly in terms of flight) and performed, but did not receive, more aggressive behaviors compared to controls. Moreover, CO2 positively affected immune function in queens, reduced transcript levels of 5/6 antioxidant enzyme genes and had no effect on longevity. Thus, although CO2 treatment stimulated reproduction, we did not observe any evidence of a trade-off in queen health parameters, aside from a reduction in lipids. Overall CO2 narcosis does not appear to stimulate a typical stress response in virgin bumble bee queens. On the contrary, CO2 narcosis appears to stimulate changes that prepare queens to cope with the nutritional, metabolic and behavioral challenges associated with reproduction and colony-founding. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Higher order visual input to the mushroom bodies in the bee, Bombus impatiens

    PubMed Central

    Paulk, Angelique C.; Gronenberg, Wulfila

    2008-01-01

    To produce appropriate behaviors based on biologically relevant associations, sensory pathways conveying different modalities are integrated by higher-order central brain structures, such as insect mushroom bodies. To address this function of sensory integration, we characterized the structure and response of optic lobe neurons projecting to the calyces of the mushroom bodies in bees. Bees are well known for their visual learning and memory capabilities and their brains possess major direct visual input from the optic lobes to the mushroom bodies. To functionally characterize these visual inputs to the mushroom bodies, we recorded intracellularly from neurons in bumblebees (Apidae: Bombus impatiens) and a single neuron in a honeybee (Apidae: Apis mellifera) while presenting color and motion stimuli. All of the mushroom body input neurons were color sensitive while a subset was motion sensitive. Additionally, most of the mushroom body input neurons would respond to the first, but not to subsequent, presentations of repeated stimuli. In general, the medulla or lobula neurons projecting to the calyx signaled specific chromatic, temporal, and motion features of the visual world to the mushroom bodies, which included sensory information required for the biologically relevant associations bees form during foraging tasks. PMID:18635397

  7. Contact networks and transmission of an intestinal pathogen in bumble bee (Bombus impatiens) colonies.

    PubMed

    Otterstatter, Michael C; Thomson, James D

    2007-11-01

    In socially living animals, individuals interact through complex networks of contact that may influence the spread of disease. Whereas traditional epidemiological models typically assume no social structure, network theory suggests that an individual's location in the network determines its risk of infection. Empirical, especially experimental, studies of disease spread on networks are lacking, however, largely due to a shortage of amenable study systems. We used automated video-tracking to quantify networks of physical contact among individuals within colonies of the social bumble bee Bombus impatiens. We explored the effects of network structure on pathogen transmission in naturally and artificially infected hives. We show for the first time that contact network structure determines the spread of a contagious pathogen (Crithidia bombi) in social insect colonies. Differences in rates of infection among colonies resulted largely from differences in network density among hives. Within colonies, a bee's rate of contact with infected nestmates emerged as the only significant predictor of infection risk. The activity of bees, in terms of their movement rates and division of labour (e.g., brood care, nest care, foraging), did not influence risk of infection. Our results suggest that contact networks may have an important influence on the transmission of pathogens in social insects and, possibly, other social animals.

  8. Macronutrient ratios in pollen shape bumble bee (Bombus impatiens) foraging strategies and floral preferences.

    PubMed

    Vaudo, Anthony D; Patch, Harland M; Mortensen, David A; Tooker, John F; Grozinger, Christina M

    2016-07-12

    To fuel their activities and rear their offspring, foraging bees must obtain a sufficient quality and quantity of nutritional resources from a diverse plant community. Pollen is the primary source of proteins and lipids for bees, and the concentrations of these nutrients in pollen can vary widely among host-plant species. Therefore we hypothesized that foraging decisions of bumble bees are driven by both the protein and lipid content of pollen. By successively reducing environmental and floral cues, we analyzed pollen-foraging preferences of Bombus impatiens in (i) host-plant species, (ii) pollen isolated from these host-plant species, and (iii) nutritionally modified single-source pollen diets encompassing a range of protein and lipid concentrations. In our semifield experiments, B impatiens foragers exponentially increased their foraging rates of pollen from plant species with high protein:lipid (P:L) ratios; the most preferred plant species had the highest ratio (∼4.6:1). These preferences were confirmed in cage studies where, in pairwise comparisons in the absence of other floral cues, B impatiens workers still preferred pollen with higher P:L ratios. Finally, when presented with nutritionally modified pollen, workers were most attracted to pollen with P:L ratios of 5:1 and 10:1, but increasing the protein or lipid concentration (while leaving ratios intact) reduced attraction. Thus, macronutritional ratios appear to be a primary factor driving bee pollen-foraging behavior and may explain observed patterns of host-plant visitation across the landscape. The nutritional quality of pollen resources should be taken into consideration when designing conservation habitats supporting bee populations.

  9. Macronutrient ratios in pollen shape bumble bee (Bombus impatiens) foraging strategies and floral preferences

    PubMed Central

    Vaudo, Anthony D.; Patch, Harland M.; Mortensen, David A.; Tooker, John F.; Grozinger, Christina M.

    2016-01-01

    To fuel their activities and rear their offspring, foraging bees must obtain a sufficient quality and quantity of nutritional resources from a diverse plant community. Pollen is the primary source of proteins and lipids for bees, and the concentrations of these nutrients in pollen can vary widely among host-plant species. Therefore we hypothesized that foraging decisions of bumble bees are driven by both the protein and lipid content of pollen. By successively reducing environmental and floral cues, we analyzed pollen-foraging preferences of Bombus impatiens in (i) host-plant species, (ii) pollen isolated from these host-plant species, and (iii) nutritionally modified single-source pollen diets encompassing a range of protein and lipid concentrations. In our semifield experiments, B. impatiens foragers exponentially increased their foraging rates of pollen from plant species with high protein:lipid (P:L) ratios; the most preferred plant species had the highest ratio (∼4.6:1). These preferences were confirmed in cage studies where, in pairwise comparisons in the absence of other floral cues, B. impatiens workers still preferred pollen with higher P:L ratios. Finally, when presented with nutritionally modified pollen, workers were most attracted to pollen with P:L ratios of 5:1 and 10:1, but increasing the protein or lipid concentration (while leaving ratios intact) reduced attraction. Thus, macronutritional ratios appear to be a primary factor driving bee pollen-foraging behavior and may explain observed patterns of host-plant visitation across the landscape. The nutritional quality of pollen resources should be taken into consideration when designing conservation habitats supporting bee populations. PMID:27357683

  10. Initial recommendations for higher-tier risk assessment protocols for bumble bees, Bombus spp. (Hymenoptera: Apidae).

    PubMed

    Cabrera, Ana R; Almanza, Maria Teresa; Cutler, G Christopher; Fischer, David L; Hinarejos, Silvia; Lewis, Gavin; Nigro, Daniel; Olmstead, Allen; Overmyer, Jay; Potter, Daniel A; Raine, Nigel E; Stanley-Stahr, Cory; Thompson, Helen; van der Steen, Jozef

    2016-04-01

    Global declines of bumble bees and other pollinator populations are of concern because of their critical role for crop production and maintenance of wild plant biodiversity. Although the consensus among scientists is that the interaction of many factors, including habitat loss, forage scarcity, diseases, parasites, and pesticides, potentially plays a role in causing these declines, pesticides have received considerable attention and scrutiny. In response, regulatory agencies have introduced more stringent pollinator testing requirements for registration and reregistration of pesticides, to ensure that the risks to pollinators are minimized. In this context, guidelines for testing bumble bees (Bombus spp.) in regulatory studies are not yet available, and a pressing need exists to develop suitable protocols for routine higher-tier studies with these non-Apis sp., social bees. To meet this need, Bayer CropScience LP, Syngenta Crop Protection LLC US, and Valent USA. Corporation organized a workshop bringing together a group of global experts on bumble bee behavior, ecology, and ecotoxicology to discuss and develop draft protocols for both semi-field (Tier II) and field (Tier III) studies. The workshop was held May 8-9, 2014, at the Bayer Bee Care Center, North Carolina, USA. The participants represented academic, consulting, and industry scientists from Europe, Canada, the United States, and Brazil. The workshop identified a clear protection goal and generated proposals for basic experimental designs, relevant measurements, and endpoints for both semifield (tunnel) and field tests. These initial recommendations are intended to form the basis of discussions to help advance the development of appropriate protocol guidelines. © 2015 The Authors. Integrated Environmental Assessment and Management Published by SETAC.

  11. Reliability of the entomovector technology using Prestop-Mix and Bombus terrestris L. as a fungal disease biocontrol method in open field

    PubMed Central

    Karise, Reet; Dreyersdorff, Gerit; Jahani, Mona; Veromann, Eve; Runno-Paurson, Eve; Kaart, Tanel; Smagghe, Guy; Mänd, Marika

    2016-01-01

    Botrytis cinerea Pers.:Fr. is a major plant pathogen, and a new approach is needed for its control in strawberry to minimise the increasing use of synthetic fungicides. The biofungicide Prestop-Mix, which contains Gliocladium catenulatum, is effective against Botrytis infections; however, the need for frequent applications increases the costs for farmers. Here, we demonstrate that bumble bees, Bombus terrestris L., effectively disseminate the preparation onto flowers in open field conditions. Over the course of three years, we found a highly significant decrease in the rate of Botrytis infection. Pathogen control was achieved with relatively low numbers of G. catenulatum spores per flower, even using flowers that are not highly attractive to bumble bees. An even distribution of spores was detected up to 100 m from the hives, either due to primary inoculation by bumble bees or secondary distribution by other flower visitors such as honey bees and solitary bees. We showed that the application of a biocontrol agent by bumble bees is reliable for the use of environmentally friendly pest control strategies in northern climatic conditions. This low cost technology is especially relevant for organic farming. This study provides valuable information for introducing this method into practice in open strawberry fields. PMID:27530075

  12. Reproductive disturbance of Japanese bumblebees by the introduced European bumblebee Bombus terrestris

    NASA Astrophysics Data System (ADS)

    Kondo, Natsuko Ito; Yamanaka, Daisei; Kanbe, Yuya; Kunitake, Yoko Kawate; Yoneda, Masahiro; Tsuchida, Koji; Goka, Koichi

    2009-04-01

    The European bumblebee, Bombus terrestris, is an invasive eusocial species whose distribution is expanding greatly beyond its native range because numerous colonies are imported to or locally produced in non-native countries for pollination of agricultural crops. Closely related species exist in Japan where the unrestricted import and use of B. terrestris has resulted in the establishment of wild colonies. Laboratory studies previously showed that B. terrestris and Japanese native species can copulate and produce fertilized eggs. Although these eggs do not hatch, the interspecific mating can cause a serious reproductive disturbance to native bumblebees. In this study, we determined the frequencies of interspecies mating between B. terrestris males and native bumblebee queens in the wild on the islands of Hokkaido and Honshu by analyzing the DNA sequences of spermatozoa stored in spermathecae of native queens. We found that 20.2% of B. hypocrita hypocrita queens and 30.2% of B. hypocrita sapporoensis queens had spermatozoa of B. terrestris males in their spermathecae. Given that a Bombus queen generally mates only once in her life, such high frequencies of interspecific mating with B. terrestris pose serious threats to the populations of native bumblebees in Japan.

  13. Israeli acute paralysis virus associated paralysis symptoms, viral tissue distribution and Dicer-2 induction in bumblebee workers (Bombus terrestris).

    PubMed

    Wang, Haidong; Meeus, Ivan; Smagghe, Guy

    2016-08-01

    Although it is known that Israeli acute paralysis virus (IAPV) can cause bee mortality, the symptoms of paralysis and the distribution of the virus in different body tissues and their potential to respond with an increase of the siRNA antiviral immune system have not been studied. In this project we worked with Bombus terrestris, which is one of the most numerous bumblebee species in Europe and an important pollinator for wild flowers and many crops in agriculture. Besides the classic symptoms of paralysis and trembling prior to death, we report a new IAPV-related symptom, crippled/immobilized forelegs. Reverse-transcriptase quantitative PCR showed that IAPV accumulates in different body tissues (midgut, fat body, brain and ovary). The highest levels of IAPV were observed in the fat body. With fluorescence in situ hybridization (FISH) we detected IAPV in the Kenyon cells of mushroom bodies and neuropils from both antennal and optic lobes of the brain in IAPV-infected workers. Finally, we observed an induction of Dicer-2, a core gene of the RNAi antiviral immune response, in the IAPV-infected tissues of B. terrestris workers. According to our results, tissue tropism and the induction strength of Dicer-2 could not be correlated with virus-related paralysis symptoms.

  14. Ultrastructure of the excretory organs of Bombus morio (Hymenoptera: Bombini): bee without rectal pads.

    PubMed

    Gonçalves, Wagner Gonzaga; Fialho, Maria do Carmo Queiroz; Azevedo, Dihego Oliveira; Zanuncio, José Cola; Serrão, José Eduardo

    2014-02-01

    Bumblebees need to keep bodily homeostasis and for that have an efficient system of excretion formed by the Malpighian tubules, ileum, and rectum. We analyzed the excretory organs of Bombus morio, a bee without rectal pads. In addition, we analyzed the rectal epithelium of Melipona quadrifasciata anthidioides which has rectal pads. The Malpighian tubules exhibited two cell types and the ileum four types. However, comparative analysis of the rectum showed that only cells of the anterior region of the rectal epithelium of B. morio are structurally distinct. We suggest that cells of the Malpighian tubules of B. morio have an excretory feature and that cells of ileum have different functions, such as ion absorption and water, organic compound, and protein secretion. In addition, only the anterior region of the rectum of B. morio showed characteristic absorption. We suggest that Malpighian tubules participate in the excretion of solutes and that the ileum and rectal epithelium are responsible for homeostasis of water and solutes, compensating for the absence of rectal papillae. These results contribute to our understanding of the morphophysiology of the excretory organs of bees without rectal pads.

  15. PCR reveals high prevalence of non/low sporulating Nosema bombi (microsporidia) infections in bumble bees (Bombus) in Northern Arizona.

    PubMed

    Blaker, Elizabeth A; Strange, James P; James, Rosalind R; Monroy, Fernando P; Cobb, Neil S

    2014-11-01

    About 20% of bumble bee species are in decline in North America, and the microsporidian pathogen, Nosema bombi, has been correlated with these declines. We conducted a comprehensive survey of N. bombi infections in the bumble bee communities throughout the flight season along an elevation gradient in Northern Arizona. Focusing on two species, Bombus (Pyrobombus) huntii and Bombus (Pyrobombus) centralis, we used a combination of PCR and microscopy to distinguish between sporulating and non/low, sporulating N. bombi infections. Surprisingly high levels of PCR-positive infections with no detectable spore loads were found in B. huntii (31-63%) and B. centralis (56.5-66.5%), while the prevalence of sporulating infections was low (3.0-11.8% and 0-12.9% respectively). We determined the prevalence of sporulating N. bombi infection in six other co-occurring, but rarer, bumble bee species (0-62.5%,), but did not test them using PCR. The prevalence of sporulating N. bombi infections in B. (Bombias) nevadensis was significantly higher than in either B. huntii or B. centralis (29%). The declining bumble bee, Bombus sensu strico occidentalis, had the highest prevalence of sporulating N. bombi infections (62.5%), but we purposely captured very few B. occidentalis because of its declining status. PCR was a more sensitive measure of N. bombi prevalence and revealed that wild bumble bees have a much higher prevalence of N. bombi than has previously been recognized. Microscopy and PCR together provide complementary, not redundant, information that deepens our understanding of the dynamic interactions between N. bombi and their bumble bee hosts. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. USBombus, a database of contemporary survey data for North American Bumble Bees (Hymenoptera, Apidae, Bombus) distributed in the United States.

    PubMed

    Koch, Jonathan B; Lozier, Jeffrey; Strange, James P; Ikerd, Harold; Griswold, Terry; Cordes, Nils; Solter, Leellen; Stewart, Isaac; Cameron, Sydney A

    2015-01-01

    Bumble bees (Hymenoptera: Apidae, Bombus) are pollinators of wild and economically important flowering plants. However, at least four bumble bee species have declined significantly in population abundance and geographic range relative to historic estimates, and one species is possibly extinct. While a wealth of historic data is now available for many of the North American species found to be in decline in online databases, systematic survey data of stable species is still not publically available. The availability of contemporary survey data is critically important for the future monitoring of wild bumble bee populations. Without such data, the ability to ascertain the conservation status of bumble bees in the United States will remain challenging. This paper describes USBombus, a large database that represents the outcomes of one of the largest standardized surveys of bumble bee pollinators (Hymenoptera, Apidae, Bombus) globally. The motivation to collect live bumble bees across the United States was to examine the decline and conservation status of Bombus affinis, B. occidentalis, B. pensylvanicus, and B. terricola. Prior to our national survey of bumble bees in the United States from 2007 to 2010, there have only been regional accounts of bumble bee abundance and richness. In addition to surveying declining bumble bees, we also collected and documented a diversity of co-occuring bumble bees. However we have not yet completely reported their distribution and diversity onto a public online platform. Now, for the first time, we report the geographic distribution of bumble bees reported to be in decline (Cameron et al. 2011), as well as bumble bees that appeared to be stable on a large geographic scale in the United States (not in decline). In this database we report a total of 17,930 adult occurrence records across 397 locations and 39 species of Bombus detected in our national survey. We summarize their abundance and distribution across the United States and

  17. USBombus, a database of contemporary survey data for North American Bumble Bees (Hymenoptera, Apidae, Bombus) distributed in the United States

    PubMed Central

    Lozier, Jeffrey; Strange, James P.; Ikerd, Harold; Griswold, Terry; Cordes, Nils; Solter, Leellen; Stewart, Isaac; Cameron, Sydney A.

    2015-01-01

    Abstract Background Bumble bees (Hymenoptera: Apidae, Bombus) are pollinators of wild and economically important flowering plants. However, at least four bumble bee species have declined significantly in population abundance and geographic range relative to historic estimates, and one species is possibly extinct. While a wealth of historic data is now available for many of the North American species found to be in decline in online databases, systematic survey data of stable species is still not publically available. The availability of contemporary survey data is critically important for the future monitoring of wild bumble bee populations. Without such data, the ability to ascertain the conservation status of bumble bees in the United States will remain challenging. New information This paper describes USBombus, a large database that represents the outcomes of one of the largest standardized surveys of bumble bee pollinators (Hymenoptera, Apidae, Bombus) globally. The motivation to collect live bumble bees across the United States was to examine the decline and conservation status of Bombus affinis, B. occidentalis, B. pensylvanicus, and B. terricola. Prior to our national survey of bumble bees in the United States from 2007 to 2010, there have only been regional accounts of bumble bee abundance and richness. In addition to surveying declining bumble bees, we also collected and documented a diversity of co-occuring bumble bees. However we have not yet completely reported their distribution and diversity onto a public online platform. Now, for the first time, we report the geographic distribution of bumble bees reported to be in decline (Cameron et al. 2011), as well as bumble bees that appeared to be stable on a large geographic scale in the United States (not in decline). In this database we report a total of 17,930 adult occurrence records across 397 locations and 39 species of Bombus detected in our national survey. We summarize their abundance and

  18. Bee Community of Commercial Potato Fields in Michigan and Bombus impatiens Visitation to Neonicotinoid-Treated Potato Plants

    PubMed Central

    Buchanan, Amanda L.; Gibbs, Jason; Komondy, Lidia; Szendrei, Zsofia

    2017-01-01

    We conducted a bee survey in neonicotinoid-treated commercial potato fields using bowl and vane traps in the 2016 growing season. Traps were placed outside the fields, at the field edges, and 10 and 30 m into the fields. We collected 756 bees representing 58 species, with Lasioglossum spp. comprising 73% of all captured bees. We found seven Bombus spp., of which B. impatiens was the only known visitor of potato flowers in our region. The majority of the bees (68%) were collected at the field edges and in the field margins. Blue vane traps caught almost four-times as many bees and collected 30% more species compared to bowl traps. Bee communities did not differ across trap locations but they were different among trap types. We tested B. impatiens visitation to neonicotinoid treated and untreated potato flowers in field enclosures. The amount of time bees spent at flowers and the duration of visits were not significantly different between the two treatments. Our results demonstrate that a diverse assemblage of bees is associated with an agroecosystem dominated by potatoes despite the apparent lack of pollinator resources provided by the crop. We found no difference in B. impatiens foraging behavior on neonicotinoid-treated compared to untreated plants. PMID:28282931

  19. Bee Community of Commercial Potato Fields in Michigan and Bombus impatiens Visitation to Neonicotinoid-Treated Potato Plants.

    PubMed

    Buchanan, Amanda L; Gibbs, Jason; Komondy, Lidia; Szendrei, Zsofia

    2017-03-09

    We conducted a bee survey in neonicotinoid-treated commercial potato fields using bowl and vane traps in the 2016 growing season. Traps were placed outside the fields, at the field edges, and 10 and 30 m into the fields. We collected 756 bees representing 58 species, with Lasioglossum spp. comprising 73% of all captured bees. We found seven Bombus spp., of which B. impatiens was the only known visitor of potato flowers in our region. The majority of the bees (68%) were collected at the field edges and in the field margins. Blue vane traps caught almost four-times as many bees and collected 30% more species compared to bowl traps. Bee communities did not differ across trap locations but they were different among trap types. We tested B. impatiens visitation to neonicotinoid treated and untreated potato flowers in field enclosures. The amount of time bees spent at flowers and the duration of visits were not significantly different between the two treatments. Our results demonstrate that a diverse assemblage of bees is associated with an agroecosystem dominated by potatoes despite the apparent lack of pollinator resources provided by the crop. We found no difference in B. impatiens foraging behavior on neonicotinoid-treated compared to untreated plants.

  20. First molecular detection of co-infection of honey bee viruses in asymptomatic Bombus atratus in South America.

    PubMed

    Reynaldi, F J; Sguazza, G H; Albicoro, F J; Pecoraro, M R; Galosi, C M

    2013-11-01

    Pollination is critical for food production and has the particularity of linking natural ecosystems with agricultural production systems. Recently, losses of bumblebee species have been reported worldwide. In this study, samples from a commercial exploitation of bumblebees of Argentina with a recent history of deaths were studied using a multiplex PCR for the detection of the honey bee viruses most frequently detected in South America. All samples analysed were positive for co-infections with Deformed wing virus, Black queen cell virus and Sacbrood virus. This is the first report of infection of Bombus atratus with honey bee viruses. A better understanding of viral infections in bumblebees and of the epidemiology of viruses could be of great importance as bumblebees can serve as possible viral reservoirs, resulting in pathogen spillover towards honey bees and native bumblebees.

  1. High Elevation Refugia for Bombus terricola (Hymenoptera: Apidae) Conservation and Wild Bees of the White Mountain National Forest

    PubMed Central

    Tucker, Erika M.; Rehan, Sandra M.

    2017-01-01

    Many wild bee species are in global decline, yet much is still unknown about their diversity and contemporary distributions. National parks and forests offer unique areas of refuge important for the conservation of rare and declining species populations. Here we present the results of the first biodiversity survey of the bee fauna in the White Mountain National Forest (WMNF). More than a thousand specimens were collected from pan and sweep samples representing 137 species. Three species were recorded for the first time in New England and an additional seven species were documented for the first time in the state of New Hampshire. Four introduced species were also observed in the specimens collected. A checklist of the species found in the WMNF, as well as those found previously in Strafford County, NH, is included with new state records and introduced species noted as well as a map of collecting locations. Of particular interest was the relatively high abundance of Bombus terricola Kirby 1837 found in many of the higher elevation collection sites and the single specimen documented of Bombus fervidus (Fabricius 1798). Both of these bumble bee species are known to have declining populations in the northeast and are categorized as vulnerable on the International Union for Conservation of Nature’s Red List. PMID:28130453

  2. High Elevation Refugia for Bombus terricola (Hymenoptera: Apidae) Conservation and Wild Bees of the White Mountain National Forest.

    PubMed

    Tucker, Erika M; Rehan, Sandra M

    2017-01-01

    Many wild bee species are in global decline, yet much is still unknown about their diversity and contemporary distributions. National parks and forests offer unique areas of refuge important for the conservation of rare and declining species populations. Here we present the results of the first biodiversity survey of the bee fauna in the White Mountain National Forest (WMNF). More than a thousand specimens were collected from pan and sweep samples representing 137 species. Three species were recorded for the first time in New England and an additional seven species were documented for the first time in the state of New Hampshire. Four introduced species were also observed in the specimens collected. A checklist of the species found in the WMNF, as well as those found previously in Strafford County, NH, is included with new state records and introduced species noted as well as a map of collecting locations. Of particular interest was the relatively high abundance of Bombus terricola Kirby 1837 found in many of the higher elevation collection sites and the single specimen documented of Bombus fervidus (Fabricius 1798). Both of these bumble bee species are known to have declining populations in the northeast and are categorized as vulnerable on the International Union for Conservation of Nature's Red List.

  3. Potential increase in mating frequency of queens in feral colonies of Bombus terrestris introduced into Japan

    NASA Astrophysics Data System (ADS)

    Inoue, Maki N.; Saito, Fuki; Tsuchida, Koji; Goka, Koichi

    2012-10-01

    With the exception of several species, bumblebees are monandrous. We examined mating frequency in feral colonies of the introduced bumblebee Bombus terrestris in Japan . Using microsatellite markers, genotyping of sperm DNA stored in the spermatheca of nine queens detected multiple insemination paternities in one queen; the others were singly mated. The average effective paternity frequency estimated from the genotypes of queens and workers was 1.23; that estimated from the workers' genotype alone was 2.12. These values were greater than those of laboratory-reared colonies in the native ranges of B. terrestris. The genotypes of one or two workers did not match those of their queens or showed paternities different from those of their nestmates; this may have arisen from either queen takeover or drifting of workers. These alien workers were responsible for the heterogeneous genotype distribution within each B. terrestris colony, resulting in higher estimates of paternity frequency than of insemination frequency. The high mating frequency of introduced B. terrestris may have occurred by artificial selection through mass breeding for commercialization. Moreover, polyandrous queens may be selectively advantageous, because reproduction by such queens is less likely to be disturbed by interspecific mating than that by monandrous queens.

  4. Characterization of Neutral Lipase BT-1 Isolated from the Labial Gland of Bombus terrestris Males

    PubMed Central

    Brabcová, Jana; Prchalová, Darina; Demianová, Zuzana; Bučánková, Alena; Vogel, Heiko; Valterová, Irena; Pichová, Iva; Zarevúcka, Marie

    2013-01-01

    Background In addition to their general role in the hydrolysis of storage lipids, bumblebee lipases can participate in the biosynthesis of fatty acids that serve as precursors of pheromones used for sexual communication. Results We studied the temporal dynamics of lipolytic activity in crude extracts from the cephalic part of Bombus terrestris labial glands. Extracts from 3-day-old males displayed the highest lipolytic activity. The highest lipase gene expression level was observed in freshly emerged bumblebees, and both gene expression and lipase activity were lower in bumblebees older than 3 days. Lipase was purified from labial glands, further characterized and named as BT-1. The B. terrestris orthologue shares 88% sequence identity with B. impatiens lipase HA. The molecular weight of B. terrestris lipase BT-1 was approximately 30 kDa, the pH optimum was 8.3, and the temperature optimum was 50°C. Lipase BT-1 showed a notable preference for C8-C10 p-nitrophenyl esters, with the highest activity toward p-nitrophenyl caprylate (C8). The Michaelis constant (Km) and maximum reaction rate (Vmax) for p-nitrophenyl laurate hydrolysis were Km = 0.0011 mM and Vmax = 0.15 U/mg. Conclusion This is the first report describing neutral lipase from the labial gland of B. terrestris. Our findings help increase understanding of its possible function in the labial gland. PMID:24260337

  5. Pollination Services Provided by Bees in Pumpkin Fields Supplemented with Either Apis mellifera or Bombus impatiens or Not Supplemented

    PubMed Central

    Petersen, Jessica D.; Reiners, Stephen; Nault, Brian A.

    2013-01-01

    Pollinators provide an important service in many crops. Managed honey bees (Apis mellifera L.) are used to supplement pollination services provided by wild bees with the assumption that they will enhance pollination, fruit set and crop yield beyond the levels provided by the wild bees. Recent declines in managed honey bee populations have stimulated interest in finding alternative managed pollinators to service crops. In the eastern U.S., managed hives of the native common eastern bumble bee (Bombus impatiens Cresson) may be an excellent choice. To examine this issue, a comprehensive 2-yr study was conducted to compare fruit yield and bee visits to flowers in pumpkin (Cucurbita pepo L.) fields that were either supplemented with A. mellifera hives, B. impatiens hives or were not supplemented. We compared pumpkin yield, A. mellifera flower visitation frequency and B. impatiens flower visitation frequency between treatments. Results indicated that supplementing pumpkin fields with either A. mellifera or B. impatiens hives did not increase their visitation to pumpkin flowers or fruit yield compared with those that were not supplemented. Next, the relationship between frequency of pumpkin flower visitation by the most prominent bee species (Peponapis pruinosa (Say), B. impatiens and A. mellifera) and fruit yield was determined across all pumpkin fields sampled. Fruit yield increased as the frequency of flower visits by A. mellifera and B. impatiens increased in 2011 and 2012, respectively. These results suggest that supplementation with managed bees may not improve pumpkin production and that A. mellifera and B. impatiens are important pollinators of pumpkin in our system. PMID:23894544

  6. Pollination services provided by bees in pumpkin fields supplemented with either Apis mellifera or Bombus impatiens or not supplemented.

    PubMed

    Petersen, Jessica D; Reiners, Stephen; Nault, Brian A

    2013-01-01

    Pollinators provide an important service in many crops. Managed honey bees (Apis mellifera L.) are used to supplement pollination services provided by wild bees with the assumption that they will enhance pollination, fruit set and crop yield beyond the levels provided by the wild bees. Recent declines in managed honey bee populations have stimulated interest in finding alternative managed pollinators to service crops. In the eastern U.S., managed hives of the native common eastern bumble bee (Bombus impatiens Cresson) may be an excellent choice. To examine this issue, a comprehensive 2-yr study was conducted to compare fruit yield and bee visits to flowers in pumpkin (Cucurbita pepo L.) fields that were either supplemented with A. mellifera hives, B. impatiens hives or were not supplemented. We compared pumpkin yield, A. mellifera flower visitation frequency and B. impatiens flower visitation frequency between treatments. Results indicated that supplementing pumpkin fields with either A. mellifera or B. impatiens hives did not increase their visitation to pumpkin flowers or fruit yield compared with those that were not supplemented. Next, the relationship between frequency of pumpkin flower visitation by the most prominent bee species (Peponapis pruinosa (Say), B. impatiens and A. mellifera) and fruit yield was determined across all pumpkin fields sampled. Fruit yield increased as the frequency of flower visits by A. mellifera and B. impatiens increased in 2011 and 2012, respectively. These results suggest that supplementation with managed bees may not improve pumpkin production and that A. mellifera and B. impatiens are important pollinators of pumpkin in our system.

  7. Nest Initiation in Three North American Species of Bumble Bees (Bombus): Effects of Gyne Number and Worker Helpers on Colony Size and Establishment Success

    USDA-ARS?s Scientific Manuscript database

    Three species of bumble bees, Bombus appositus, B. bifarius, and B. centralis (Hymenoptera: Apidae) were evaluated for nest initiation success under three sets of initial conditions. In the spring, queens of each species were caught in the wild and introduced to nest boxes in one of three ways. Qu...

  8. Dynamics of immune system gene expression upon bacterial challenge and wounding in a social insect (Bombus terrestris).

    PubMed

    Erler, Silvio; Popp, Mario; Lattorff, H Michael G

    2011-03-29

    The innate immune system which helps individuals to combat pathogens comprises a set of genes representing four immune system pathways (Toll, Imd, JNK and JAK/STAT). There is a lack of immune genes in social insects (e.g. honeybees) when compared to Diptera. Potentially, this might be compensated by an advanced system of social immunity (synergistic action of several individuals). The bumble bee, Bombus terrestris, is a primitively eusocial species with an annual life cycle and colonies headed by a single queen. We used this key pollinator to study the temporal dynamics of immune system gene expression in response to wounding and bacterial challenge.Antimicrobial peptides (AMP) (abaecin, defensin 1, hymenoptaecin) were strongly up-regulated by wounding and bacterial challenge, the latter showing a higher impact on the gene expression level. Sterile wounding down-regulated TEP A, an effector gene of the JAK/STAT pathway, and bacterial infection influenced genes of the Imd (relish) and JNK pathway (basket). Relish was up-regulated within the first hour after bacterial challenge, but decreased strongly afterwards. AMP expression following wounding and bacterial challenge correlates with the expression pattern of relish whereas correlated expression with dorsal was absent. Although expression of AMPs was high, continuous bacterial growth was observed throughout the experiment.Here we demonstrate for the first time the temporal dynamics of immune system gene expression in a social insect. Wounding and bacterial challenge affected the innate immune system significantly. Induction of AMP expression due to wounding might comprise a pre-adaptation to accompanying bacterial infections. Compared with solitary species this social insect exhibits reduced immune system efficiency, as bacterial growth could not be inhibited. A negative feedback loop regulating the Imd-pathway is suggested. AMPs, the end product of the Imd-pathway, inhibited the up-regulation of the transcription

  9. Comparison of the efficiency of the bumble bees Bombus impatiens and Bombus ephippiatus (Hymenoptera: Apidae) as pollinators of tomato in greenhouses.

    PubMed

    Torres-Ruiz, Alfonso; Jones, Robert W

    2012-12-01

    Experiments were conducted in a commercial tomato, Solanum lycopersicum L. (Solanaceae) greenhouse to compare the relative foraging effort and efficiency of two bumble bee species: Bombus impatiens Cresson, a species from northeastern North America, commercially reared and used for pollination in Mexico; and B. ephippiatus Say, a native species of Mexico and central America. B. ephippiatus was as efficient in pollination of tomatoes as B. impatiens, as indicated by all variables of fruit quality: fruit weight, number of seed per fruit, and maximum fruit diameter. The two species had similar levels of hourly and daily foraging activity. They had the same response to temperature fluctuation. Pollination rates by both species were similar and close to 100% throughout the sample period. However, B. impatiens showed greater foraging activity during the first half of the 27-d sample period, whereas B. ephipiatus had greater relative activity during the last half. This study establish that B. ephippiatus is as efficient as B. impatiens as a pollinator of tomatoes in greenhouses and thus a candidate as a managed pollinator. However, standard reliable methods for mass rearing of B. ephippiatus are not yet available. Such methods are necessary to ensure healthy colonies and optimum pollination for producers and will reduce the pressure for the unregulated collection of queens in the field and the subsequent reduction of populations of this species.

  10. Insect vision models under scrutiny: what bumblebees (Bombus terrestris terrestris L.) can still tell us.

    PubMed

    Telles, Francismeire Jane; Rodríguez-Gironés, Miguel A

    2015-02-01

    Three contending models address the ability of bees to detect and discriminate colours: the colour opponent coding (COC) model, the colour hexagon (CH) model and the receptor noise-limited (RN) model, but few studies attempt to determine which model fits experimental data best. To assess whether the models provide an accurate description of bumblebee colour space, we trained bees to discriminate four colour pairs. The perceptual distance between the colours of each pair was similar according to the CH model but varied widely according to the COC and RN models. The time that bees required to select a flower and the proportion of correct choices differed between groups: decision times decreased as achromatic contrast increased, and the proportion of correct choices increased with achromatic contrast and perceptual distance, as predicted by the COC and RN models. These results suggest that both chromatic and achromatic contrasts affected the discriminability of colour pairs. Since flower colour affects the foraging choices of bees and foraging choices affect the reproductive success of plants, a better understanding of which model is more accurate under each circumstance is required to predict bee behaviour and the ecological implications of flower choice and colour.

  11. Insect vision models under scrutiny: what bumblebees ( Bombus terrestris terrestris L.) can still tell us

    NASA Astrophysics Data System (ADS)

    Telles, Francismeire Jane; Rodríguez-Gironés, Miguel A.

    2015-02-01

    Three contending models address the ability of bees to detect and discriminate colours: the colour opponent coding (COC) model, the colour hexagon (CH) model and the receptor noise-limited (RN) model, but few studies attempt to determine which model fits experimental data best. To assess whether the models provide an accurate description of bumblebee colour space, we trained bees to discriminate four colour pairs. The perceptual distance between the colours of each pair was similar according to the CH model but varied widely according to the COC and RN models. The time that bees required to select a flower and the proportion of correct choices differed between groups: decision times decreased as achromatic contrast increased, and the proportion of correct choices increased with achromatic contrast and perceptual distance, as predicted by the COC and RN models. These results suggest that both chromatic and achromatic contrasts affected the discriminability of colour pairs. Since flower colour affects the foraging choices of bees and foraging choices affect the reproductive success of plants, a better understanding of which model is more accurate under each circumstance is required to predict bee behaviour and the ecological implications of flower choice and colour.

  12. Isolation and properties of flight muscle mitochondria of the bumblebee Bombus terrestris (L.).

    PubMed

    Syromyatnikov, M Yu; Lopatin, A V; Starkov, A A; Popov, V N

    2013-08-01

    This report describes the isolation procedure and properties of tightly coupled flight muscle mitochondria of the bumblebee Bombus terrestris (L.). The highest respiratory control index was observed upon oxidation of pyruvate, whereas the highest respiration rates were registered upon oxidation of a combination of the following substrates: pyruvate + malate, pyruvate + proline, or pyruvate + glutamate. The respiration rates upon oxidation of malate, glutamate, glutamate + malate, or succinate were very low. At variance with flight muscle mitochondria of a number of other insects reported earlier, B. terrestris mitochondria did not show high rates of respiration supported by oxidation of proline. The maximal respiration rates were observed upon oxidation of α-glycerophosphate. Bumblebee mitochondria are capable of maintaining high membrane potential in the absence of added respiratory substrates, which was completely dissipated by the addition of rotenone, suggesting high amount of intramitochondrial NAD-linked oxidative substrates. Pyruvate and α-glycerophosphate appear to be the optimal oxidative substrates for maintaining the high rates of oxidative metabolism of the bumblebee mitochondria.

  13. Age- and task-dependent foraging gene expression in the bumblebee Bombus terrestris.

    PubMed

    Tobback, Julie; Mommaerts, Veerle; Vandersmissen, Hans Peter; Smagghe, Guy; Huybrechts, Roger

    2011-01-01

    In eusocial insects, the division of labor within a colony, based on either age or size, is correlated with a differential foraging (for) gene expression and PKG activity. This article presents in the first part a study on the for gene, encoding a cGMP-dependent protein kinase (PKG) in the bumblebee Bombus terrestris. Cloning of the open reading frame allowed phylogenetic tracing, which showed conservation of PKGs among social insects. Our results confirm the proposed role for PKGs in division of labor. Btfor gene expression is significantly higher in the larger foragers compared with the smaller sized nurses. More importantly, we discovered an age-related decrease in Btfor expression in both nursing and foraging bumblebees. We therefore speculate that the presence of BtFOR is required for correct adaptation to new external stimuli and rapid learning for foraging. In a second series of experiments, worker bumblebees of B. terrestris were treated with two insecticides imidacloprid and kinoprene, which have shown to cause impaired foraging behavior. Compared with controls, only the latter treatment resulted in a decreased Btfor expression, which concurs with a stimulation of ovarian growth and a shift in labor toward nest-related tasks. The data are discussed in relation to Btfor expression in the complex physiological event of foraging and side-effects by pesticides.

  14. Factors influencing Nosema bombi infections in natural populations of Bombus terrestris (Hymenoptera: Apidae).

    PubMed

    Huth-Schwarz, Anett; Settele, Josef; Moritz, Robin F A; Kraus, F Bernhard

    2012-05-01

    Bumblebees are of profound ecological importance because of the pollination services they provide in natural and agricultural ecosystems. Any decline of these pollinators is therefore of great concern for ecosystem functioning. Increased parasite pressures have been discussed as a major factor for the loss of pollinators. One of the main parasites of bumblebees is Nosema bombi, an intracellular microsporidian parasite with considerable impact on the vitality of the host. Here we study the effect of host colony density and host genetic variability on N. bombi infections in natural populations of the bumblebee Bombus terrestris. We sampled males and workers from six B. terrestris populations located in an agricultural landscape in Middle Sweden to determine the prevalence and degree of N. bombi infections. All individuals were genotyped with five microsatellite markers to infer the colony densities in the sampled populations and the genetic variability of the host population. We confirmed that genetic variability and sex significantly correlate with the degree of infection with N. bombi. Males and workers with lower genetic variability had significantly higher infection levels than average. Also colony density had a significant impact on the degree of infection, with high density populations having higher infected individuals. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Managed Bumble Bees (Bombus impatiens) (Hymenoptera: Apidae) Caged With Blueberry Bushes at High Density Did Not Increase Fruit Set or Fruit Weight Compared to Open Pollination.

    PubMed

    Campbell, J W; O'Brien, J; Irvin, J H; Kimmel, C B; Daniels, J C; Ellis, J D

    2017-02-17

    Highbush blueberry (Vaccinium corymbosum L.) is an important crop grown throughout Florida. Currently, most blueberry growers use honey bees (Apis mellifera L.) to provide pollination services for highbush blueberries even though bumble bees (Bombus spp.) have been shown to be more efficient at pollinating blueberries on a per bee basis. In general, contribution of bumble bees to the pollination of commercial highbush blueberries in Florida is unknown. Herein, we determined if managed bumble bees could contribute to highbush blueberry pollination. There were four treatments in this study: two treatments of caged commercial bumble bee (Bombus impatiens Cresson) colonies (low and high weight hives), a treatment excluding all pollinators, and a final treatment which allowed all pollinators (managed and wild pollinators) in the area have access to the plot. All treatments were located within a highbush blueberry field containing two cultivars of blooming plants, 'Emerald' and 'Millennia', with each cage containing 16 mature blueberry plants. We gathered data on fruit set, berry weight, and number of seeds produced per berry. When pollinators were excluded, fruit set was significantly lower in both cultivars (<8%) compared to that in all of the other treatments (>58%). Berry weight was not significantly different among the treatments, and the number of seeds per berry did not show a clear response. This study emphasizes the importance of bumble bees as an effective pollinator of blueberries and the potential beneficial implications of the addition of bumble bees in commercial blueberry greenhouses or high tunnels.

  16. In vivo study of Dicer-2-mediated immune response of the small interfering RNA pathway upon systemic infections of virulent and avirulent viruses in Bombus terrestris.

    PubMed

    Niu, Jinzhi; Smagghe, Guy; De Coninck, Dieter I M; Van Nieuwerburgh, Filip; Deforce, Dieter; Meeus, Ivan

    2016-03-01

    Recent studies suggest a potent role of the small interfering RNA (siRNA) pathway in the control of bee viruses and its usefulness to tackle these viral diseases. However, the involvement of the siRNA pathway in the defense against different bee viruses is still poorly understood. Therefore, in this report, we comprehensively analyzed the response of the siRNA pathway in bumblebees of Bombus terrestris to systemic infections of the virulent Israeli acute paralysis virus (IAPV) and the avirulent slow bee paralysis virus (SBPV). Our results showed that IAPV and SBPV infections induced the expression of Dicer-2. IAPV infections also triggered the production of predominantly 22 nt-long virus-derived siRNAs (vsiRNAs). Intriguingly, these 22 nt-long vsiRNAs showed a high proportion of antigenomic IAPV sequences. Conversely, these predominantly 22 nt-long vsiRNAs of SBPV were not detected in SBPV infected bees. Furthermore, an "RNAi-of-RNAi" experiment on Dicer-2 did not result in altered genome copy numbers of IAPV (n = 17-18) and also not of SBPV (n = 11-12). Based on these results, we can speculate about the importance of the siRNA pathway in bumblebees for the antiviral response. During infection of IAPV, this pathway is probably recruited but it might be insufficient to control viral infection in our experimental setup. The host can control SBPV infection, but aside from the induction of Dicer-2 expression, no further evidence of the antiviral activity of the siRNA pathway was observed. This report may also enhance the current understanding of the siRNA pathway in the innate immunity of non-model insects upon different viral infections.

  17. Protein-poor diet reduces host-specific immune gene expression in Bombus terrestris

    PubMed Central

    Brunner, Franziska S.; Schmid-Hempel, Paul; Barribeau, Seth M.

    2014-01-01

    Parasites infect hosts non-randomly as genotypes of hosts vary in susceptibility to the same genotypes of parasites, but this specificity may be modulated by environmental factors such as nutrition. Nutrition plays an important role for any physiological investment. As immune responses are costly, resource limitation should negatively affect immunity through trade-offs with other physiological requirements. Consequently, nutritional limitation should diminish immune capacity in general, but does it also dampen differences among hosts? We investigated the effect of short-term pollen deprivation on the immune responses of our model host Bombus terrestris when infected with the highly prevalent natural parasite Crithidia bombi. Bumblebees deprived of pollen, their protein source, show reduced immune responses to infection. They failed to upregulate a number of genes, including antimicrobial peptides, in response to infection. In particular, they also showed less specific immune expression patterns across individuals and colonies. These findings provide evidence for how immune responses on the individual-level vary with important elements of the environment and illustrate how nutrition can functionally alter not only general resistance, but also alter the pattern of specific host–parasite interactions. PMID:24850921

  18. Molecular heterochrony and the evolution of sociality in bumblebees (Bombus terrestris)

    PubMed Central

    Woodard, S. Hollis; Bloch, Guy M.; Band, Mark R.; Robinson, Gene E.

    2014-01-01

    Sibling care is a hallmark of social insects, but its evolution remains challenging to explain at the molecular level. The hypothesis that sibling care evolved from ancestral maternal care in primitively eusocial insects has been elaborated to involve heterochronic changes in gene expression. This elaboration leads to the prediction that workers in these species will show patterns of gene expression more similar to foundress queens, who express maternal care behaviour, than to established queens engaged solely in reproductive behaviour. We tested this idea in bumblebees (Bombus terrestris) using a microarray platform with approximately 4500 genes. Unlike the wasp Polistes metricus, in which support for the above prediction has been obtained, we found that patterns of brain gene expression in foundress and queen bumblebees were more similar to each other than to workers. Comparisons of differentially expressed genes derived from this study and gene lists from microarray studies in Polistes and the honeybee Apis mellifera yielded a shared set of genes involved in the regulation of related social behaviours across independent eusocial lineages. Together, these results suggest that multiple independent evolutions of eusociality in the insects might have involved different evolutionary routes, but nevertheless involved some similarities at the molecular level. PMID:24552837

  19. Evaluation of the toxicity of fungicides to flight muscle mitochondria of bumblebee (Bombus terrestris L.).

    PubMed

    Syromyatnikov, Mikhail Y; Kokina, Anastasia V; Lopatin, Alexey V; Starkov, Anatoly A; Popov, Vasily N

    2017-01-01

    Insects pollinate 75% of crops used for human consumption. Over the last decade, a substantial reduction in the abundance of pollinating insects has been recorded and recognized as a severe matter for food supply security. Many of the important food crops destined for human consumption are grown in greenhouses. A unique feature of greenhouse agriculture is the extensive use of fungicides to curb multiple fungal infections. The most widely used pollinating insects in greenhouses are commercially reared bumblebees. However, there is no data regarding the toxicity of fungicides to bumblebee mitochondria. To fill this gap in knowledge, we examined the effects of 16 widely used fungicides on the energetics of the flight muscles mitochondria of Bombus terrestris. We found that diniconazole and fludioxonil uncoupled the respiration of mitochondria; dithianon and difenoconazole inhibited it. By analyzing the action of these inhibitors on mitochondrial respiration and generation of reactive oxygen species, we concluded that difenoconazole inhibited electron transport at the level of Complex I and glycerol-3-phosphate dehydrogenase. Dithianon strongly inhibited succinate dehydrogenase and glycerol-3-phosphate dehydrogenase. It also strongly inhibited mitochondrial oxidation of NAD-linked substrates or glycerol 3-phosphate, but it had no effect on the enzymatic activity of Complex I. It may be suggested that dithianon inhibits electron transport downstream of Complex I, likely at multiply sites. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Chemical reproductive traits of diploid Bombus terrestris males: Consequences on bumblebee conservation.

    PubMed

    Lecocq, Thomas; Gérard, Maxence; Maebe, Kevin; Brasero, Nicolas; Dehon, Lauren; Smagghe, Guy; Valterová, Irena; De Meulemeester, Thibaut; Rasmont, Pierre; Michez, Denis

    2016-03-07

    The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this paper, we investigate for the first time a potential pre-mating mechanism through a major chemical reproductive trait (male cephalic labial gland secretions) that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males of Bombus terrestris (L.). Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through pre-mating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens. This article is protected by copyright. All rights reserved.

  1. Hazards and uptake of chitin synthesis inhibitors in bumblebees Bombus terrestris.

    PubMed

    Mommaerts, Veerle; Sterk, Guido; Smagghe, Guy

    2006-08-01

    This research project examined the potential hazards of a major class of insect growth regulators (IGRs) to survival, reproduction and larval growth in bumblebees Bombus terrestris L. Eight chitin synthesis inhibitors (CSIs) were tested: buprofezin, cyromazine, diflubenzuron, flucycloxuron, flufenoxuron, lufenuron, novaluron and teflubenzuron. These different IGRs, which are important in the control of pest insects in greenhouses, were applied via three different routes of exposure under laboratory conditions: dermal contact, and orally via the drinking of sugar/water and via pollen. The compounds were tested at their respective maximum field recommended concentrations (MFRC) and also in dose-response assays to calculate LC(50) values. In general, none of the CSIs showed acute worker toxicity. However, there was a dramatic reduction in brood production, especially after oral treatment with pollen and sugar/water. Conspicuously, egg fertility was reduced in all treatments with diflubenzuron and teflubenzuron. In addition to egg mortality, the worker bumblebees removed larvae from the treated nest, and in most cases these individuals were dead first-second instars. Under a binocular microscope, such larvae showed an abnormally formed cuticle leading to mechanical weakness and death. In another series of experiments using (14)C-diflubenzuron and (14)C-flufenoxuron, cuticular penetration in workers was studied for a better understanding of the differences in toxicity. With (14)C-diflubenzuron, transovarial transport and accumulation in the deposited eggs supported the strong reproductive effects. Overall, the present results suggest that CSIs should be applied with caution in combination with bumblebees. The compatibility of each compound to be used in combination with B. terrestris is discussed in relation to calculated LC(50) values, routes of uptake and effects.

  2. Lethal and sublethal effects of azadirachtin on the bumblebee Bombus terrestris (Hymenoptera: Apidae).

    PubMed

    Barbosa, Wagner Faria; De Meyer, Laurens; Guedes, Raul Narciso C; Smagghe, Guy

    2015-01-01

    Azadirachtin is a biorational insecticide commonly reported as selective to a range of beneficial insects. Nonetheless, only few studies have been carried out with pollinators, usually emphasizing the honeybee Apis mellifera and neglecting other important pollinator species such as the bumblebee Bombus terrestris. Here, lethal and sublethal effects of azadirachtin were studied on B. terrestris via oral exposure in the laboratory to bring out the potential risks of the compound to this important pollinator. The compound was tested at different concentrations above and below the maximum concentration that is used in the field (32 mg L(-1)). As most important results, azadirachtin repelled bumblebee workers in a concentration-dependent manner. The median repellence concentration (RC50) was estimated as 504 mg L(-1). Microcolonies chronically exposed to azadirachtin via treated sugar water during 11 weeks in the laboratory exhibited a high mortality ranging from 32 to 100 % with a range of concentrations between 3.2 and 320 mg L(-1). Moreover, no reproduction was scored when concentrations were higher than 3.2 mg L(-1). At 3.2 mg L(-1), azadirachtin significantly inhibited the egg-laying and, consequently, the production of drones during 6 weeks. Ovarian length decreased with the increase of the azadirachtin concentration. When azadirachtin was tested under an experimental setup in the laboratory where bumblebees need to forage for food, the sublethal effects were stronger as the numbers of drones were reduced already with a concentration of 0.64 mg L(-1). Besides, a negative correlation was found between the body mass of male offspring and azadirachtin concentration. In conclusion, our results as performed in the laboratory demonstrated that azadirachtin can affect B. terrestris with a range of sublethal effects. Taking into account that sublethal effects are as important as lethal effects for the development and survival of the colonies of B. terrestris

  3. Can red flowers be conspicuous to bees? Bombus dahlbomii and South American temperate forest flowers as a case in point.

    PubMed

    Martínez-Harms, J; Palacios, A G; Márquez, N; Estay, P; Arroyo, M T K; Mpodozis, J

    2010-02-15

    It has been argued that trichromatic bees with photoreceptor spectral sensitivity peaks in the ultraviolet (UV), blue and green areas of the spectrum are blind to long wavelengths (red to humans). South American temperate forests (SATF) contain a large number of human red-looking flowers that are reported to be visited by the bumblebee Bombus dahlbomii. In the present study, B. dahlbomii's spectral sensitivity was measured through electroretinogram (ERG) recordings. No extended sensitivity to long wavelengths was found in B. dahlbomii. The spectral reflectance curves from eight plant species with red flowers were measured. The color loci occupied by these flowers in the bee color space was evaluated using the receptor noise-limited model. Four of the plant species have pure red flowers with low levels of chromatic contrast but high levels of negative L-receptor contrast. Finally, training experiments were performed in order to assess the role of achromatic cues in the detection and discrimination of red targets by B. dahlbomii. The results of the training experiments suggest that the bumblebee relies on achromatic contrast provided by the L-receptor to detect and discriminate red targets. These findings are discussed in the context of the evolutionary background under which the relationship between SATF species and their flower visitors may have evolved.

  4. Bombus terrestris as pollinator-and-vector to suppress Botrytis cinerea in greenhouse strawberry.

    PubMed

    Mommaerts, Veerle; Put, Kurt; Smagghe, Guy

    2011-09-01

    Bombus terrestris L. bumblebees are widely used as commercial pollinators, but they might also be of help in the battle against economically important crop diseases. This alternative control strategy is referred to as pollinator-and-vector technology. The present study was designed to investigate the capacity of B. terrestris to fulfil this role in greenhouse strawberry flowers, which were manually inoculated with a major plant pathogen, the grey mould Botrytis cinerea Pers.: Fr. A model microbiological control agent (MCA) product Prestop-Mix was loaded in a newly developed two-way bumblebee dispenser, and, in addition, the use of the diluent Maizena-Plus (corn starch) was tested. Importantly, loading of the MCA caused no adverse effects on bumblebee workers, with no loss of survival or impairment of flight activity of the workers during the 4 week flowering period. Secondly, vectoring of Prestop-Mix by bumblebees resulted in a higher crop production, as 71% of the flowers developed into healthy red strawberries at picking (preharvest yield) as compared with 54% in the controls. In addition, these strawberries were better protected, as 79% of the picked berries remained free of B. cinerea after a 2 day incubation (post-harvest yield), while this percentage was only 43% in the control. Overall, the total yield (preharvest × post-harvest) was 2-2.5 times higher than the total yield in the controls (24%) in plants exposed to bumblebees vectoring Prestop-Mix. Thirdly, the addition of the diluent Maizena-Plus to Prestop-Mix at 1:1 (w/w) resulted in a similar yield to that of Prestop-Mix used alone, and in no negative effects on the bumblebees, flowers and berries. This greenhouse study provides strong evidence that B. terrestris bumblebees can vector a MCA to reduce B. cinerea incidence in greenhouse strawberries, resulting in higher yields. Similar yields obtained in the treatments with Prestop-Mix and Prestop-Mix + Maizena-Plus suggest an equally efficient

  5. A second generation genetic map of the bumblebee Bombus terrestris (Linnaeus, 1758) reveals slow genome and chromosome evolution in the Apidae

    PubMed Central

    2011-01-01

    Background The bumblebee Bombus terrestris is an ecologically and economically important pollinator and has become an important biological model system. To study fundamental evolutionary questions at the genomic level, a high resolution genetic linkage map is an essential tool for analyses ranging from quantitative trait loci (QTL) mapping to genome assembly and comparative genomics. We here present a saturated linkage map and match it with the Apis mellifera genome using homologous markers. This genome-wide comparison allows insights into structural conservations and rearrangements and thus the evolution on a chromosomal level. Results The high density linkage map covers ~ 93% of the B. terrestris genome on 18 linkage groups (LGs) and has a length of 2'047 cM with an average marker distance of 4.02 cM. Based on a genome size of ~ 430 Mb, the recombination rate estimate is 4.76 cM/Mb. Sequence homologies of 242 homologous markers allowed to match 15 B. terrestris with A. mellifera LGs, five of them as composites. Comparing marker orders between both genomes we detect over 14% of the genome to be organized in synteny and 21% in rearranged blocks on the same homologous LG. Conclusions This study demonstrates that, despite the very high recombination rates of both A. mellifera and B. terrestris and a long divergence time of about 100 million years, the genomes' genetic architecture is highly conserved. This reflects a slow genome evolution in these bees. We show that data on genome organization and conserved molecular markers can be used as a powerful tool for comparative genomics and evolutionary studies, opening up new avenues of research in the Apidae. PMID:21247459

  6. Colonies of bumble bees (Bombus impatiens) produce fewer workers, less bee biomass, and have smaller mother queens following fungicide exposure

    USDA-ARS?s Scientific Manuscript database

    Bees provide vital pollination services to the majority of flowering plants in both natural and agricultural systems. Unfortunately, both native and managed bee populations are experiencing serious declines, threatening the persistence of these plants and crops. Agricultural chemicals are one possib...

  7. Can Winter-Active Bumblebees Survive the Cold? Assessing the Cold Tolerance of Bombus terrestris audax and the Effects of Pollen Feeding

    PubMed Central

    Owen, Emily L.; Bale, Jeffrey S.; Hayward, Scott A. L.

    2013-01-01

    There is now considerable evidence that climate change is disrupting the phenology of key pollinator species. The recently reported UK winter activity of the bumblebee Bombus terrestris brings a novel set of thermal challenges to bumblebee workers that would typically only be exposed to summer conditions. Here we assess the ability of workers to survive acute and chronic cold stress (via lower lethal temperatures and lower lethal times at 0°C), the capacity for rapid cold hardening (RCH) and the influence of diet (pollen versus nectar consumption) on supercooling points (SCP). Comparisons are made with chronic cold stress indices and SCPs in queen bumblebees. Results showed worker bees were able to survive acute temperatures likely to be experienced in a mild winter, with queens significantly more tolerant to chronic cold temperature stress. The first evidence of RCH in any Hymenoptera is shown. In addition, dietary manipulation indicated the consumption of pollen significantly increased SCP temperature. These results are discussed in the light of winter active bumblebees and climate change. PMID:24224036

  8. Unraveling the venom proteome of the bumblebee (Bombus terrestris) by integrating a combinatorial peptide ligand library approach with FT-ICR MS.

    PubMed

    Van Vaerenbergh, Matthias; Debyser, Griet; Smagghe, Guy; Devreese, Bart; de Graaf, Dirk C

    2015-08-01

    Within the Apidae, the largest family of bees with over 5600 described species, the honeybee is the sole species with a well studied venom proteome. So far, only little research has focused on bumblebee venom. Recently, the genome sequence of the European large earth bumblebee (Bombus terrestris) became available and this allowed the first in-depth proteomic analysis of its venom composition. We identified 57 compounds, with 52 of them never described in bumblebee venom. Remarkably, 72% of the detected compounds were found to have a honeybee venom homolog, which reflects the similar defensive function of both venoms and the high degree of homology between both genomes. However, both venoms contain a selection of species-specific toxins, revealing distinct damaging effects that may have evolved in response to species-specific attackers. Further, this study extends the list of potential venom allergens. The availability of both the honeybee and bumblebee venom proteome may help to develop a strategy that solves the current issue of false double sensitivity in allergy diagnosis, which is caused by cross-reactivity between both venoms. A correct diagnosis is important as it is recommended to perform an immunotherapy with venom of the culprit species.

  9. Dumb and Lazy? A Comparison of Color Learning and Memory Retrieval in Drones and Workers of the Buff-Tailed Bumblebee, Bombus terrestris, by Means of PER Conditioning

    PubMed Central

    Lichtenstein, Leonie; Sommerlandt, Frank M. J.; Spaethe, Johannes

    2015-01-01

    More than 100 years ago, Karl von Frisch showed that honeybee workers learn and discriminate colors. Since then, many studies confirmed the color learning capabilities of females from various hymenopteran species. Yet, little is known about visual learning and memory in males despite the fact that in most bee species males must take care of their own needs and must find rewarding flowers to obtain food. Here we used the proboscis extension response (PER) paradigm to study the color learning capacities of workers and drones of the bumblebee, Bombus terrestris. Light stimuli were paired with sucrose reward delivered to the insects’ antennae and inducing a reflexive extension of the proboscis. We evaluated color learning (i.e. conditioned PER to color stimuli) in absolute and differential conditioning protocols and mid-term memory retention was measured two hours after conditioning. Different monochromatic light stimuli in combination with neutral density filters were used to ensure that the bumblebees could only use chromatic and not achromatic (e.g. brightness) information. Furthermore, we tested if bees were able to transfer the learned information from the PER conditioning to a novel discrimination task in a Y-maze. Both workers and drones were capable of learning and discriminating between monochromatic light stimuli and retrieved the learned stimulus after two hours. Drones performed as well as workers during conditioning and in the memory test, but failed in the transfer test in contrast to workers. Our data clearly show that bumblebees can learn to associate a color stimulus with a sugar reward in PER conditioning and that both workers and drones reach similar acquisition and mid-term retention performances. Additionally, we provide evidence that only workers transfer the learned information from a Pavlovian to an operant situation. PMID:26230643

  10. Dumb and Lazy? A Comparison of Color Learning and Memory Retrieval in Drones and Workers of the Buff-Tailed Bumblebee, Bombus terrestris, by Means of PER Conditioning.

    PubMed

    Lichtenstein, Leonie; Sommerlandt, Frank M J; Spaethe, Johannes

    2015-01-01

    More than 100 years ago, Karl von Frisch showed that honeybee workers learn and discriminate colors. Since then, many studies confirmed the color learning capabilities of females from various hymenopteran species. Yet, little is known about visual learning and memory in males despite the fact that in most bee species males must take care of their own needs and must find rewarding flowers to obtain food. Here we used the proboscis extension response (PER) paradigm to study the color learning capacities of workers and drones of the bumblebee, Bombus terrestris. Light stimuli were paired with sucrose reward delivered to the insects' antennae and inducing a reflexive extension of the proboscis. We evaluated color learning (i.e. conditioned PER to color stimuli) in absolute and differential conditioning protocols and mid-term memory retention was measured two hours after conditioning. Different monochromatic light stimuli in combination with neutral density filters were used to ensure that the bumblebees could only use chromatic and not achromatic (e.g. brightness) information. Furthermore, we tested if bees were able to transfer the learned information from the PER conditioning to a novel discrimination task in a Y-maze. Both workers and drones were capable of learning and discriminating between monochromatic light stimuli and retrieved the learned stimulus after two hours. Drones performed as well as workers during conditioning and in the memory test, but failed in the transfer test in contrast to workers. Our data clearly show that bumblebees can learn to associate a color stimulus with a sugar reward in PER conditioning and that both workers and drones reach similar acquisition and mid-term retention performances. Additionally, we provide evidence that only workers transfer the learned information from a Pavlovian to an operant situation.

  11. Bumble bees (Hymenoptera: Apidae: Bombus spp.) of interior Alaska: Species composition, distribution, seasonal biology, and parasites

    USDA-ARS?s Scientific Manuscript database

    Despite the ecological and agricultural significance of bumble bees in Alaska, very little is known and published about this important group at the regional level. The objectives of this study were to provide baseline data on species composition, distribution, seasonal biology, and parasites of the ...

  12. The Abundance and Pollen Foraging Behaviour of Bumble Bees in Relation to Population Size of Whortleberry (Vaccinium uliginosum)

    PubMed Central

    Mayer, Carolin; Michez, Denis; Chyzy, Alban; Brédat, Elise; Jacquemart, Anne-Laure

    2012-01-01

    Habitat fragmentation can have severe effects on plant pollinator interactions, for example changing the foraging behaviour of pollinators. To date, the impact of plant population size on pollen collection by pollinators has not yet been investigated. From 2008 to 2010, we monitored nine bumble bee species (Bombus campestris, Bombus hortorum s.l., Bombus hypnorum, Bombus lapidarius, Bombus pascuorum, Bombus pratorum, Bombus soroensis, Bombus terrestris s.l., Bombus vestalis s.l.) on Vaccinium uliginosum (Ericaceae) in up to nine populations in Belgium ranging in size from 80 m2 to over 3.1 ha. Bumble bee abundance declined with decreasing plant population size, and especially the proportion of individuals of large bumble bee species diminished in smaller populations. The most remarkable and novel observation was that bumble bees seemed to switch foraging behaviour according to population size: while they collected both pollen and nectar in large populations, they largely neglected pollen collection in small populations. This pattern was due to large bumble bee species, which seem thus to be more likely to suffer from pollen shortages in smaller habitat fragments. Comparing pollen loads of bumble bees we found that fidelity to V. uliginosum pollen did not depend on plant population size but rather on the extent shrub cover and/or openness of the site. Bumble bees collected pollen only from three plant species (V. uliginosum, Sorbus aucuparia and Cytisus scoparius). We also did not discover any pollination limitation of V. uliginosum in small populations. We conclude that habitat fragmentation might not immediately threaten the pollination of V. uliginosum, nevertheless, it provides important nectar and pollen resources for bumble bees and declining populations of this plant could have negative effects for its pollinators. The finding that large bumble bee species abandon pollen collection when plant populations become small is of interest when considering plant and

  13. The abundance and pollen foraging behaviour of bumble bees in relation to population size of whortleberry (Vaccinium uliginosum).

    PubMed

    Mayer, Carolin; Michez, Denis; Chyzy, Alban; Brédat, Elise; Jacquemart, Anne-Laure

    2012-01-01

    Habitat fragmentation can have severe effects on plant pollinator interactions, for example changing the foraging behaviour of pollinators. To date, the impact of plant population size on pollen collection by pollinators has not yet been investigated. From 2008 to 2010, we monitored nine bumble bee species (Bombus campestris, Bombus hortorum s.l., Bombus hypnorum, Bombus lapidarius, Bombus pascuorum, Bombus pratorum, Bombus soroensis, Bombus terrestris s.l., Bombus vestalis s.l.) on Vaccinium uliginosum (Ericaceae) in up to nine populations in Belgium ranging in size from 80 m(2) to over 3.1 ha. Bumble bee abundance declined with decreasing plant population size, and especially the proportion of individuals of large bumble bee species diminished in smaller populations. The most remarkable and novel observation was that bumble bees seemed to switch foraging behaviour according to population size: while they collected both pollen and nectar in large populations, they largely neglected pollen collection in small populations. This pattern was due to large bumble bee species, which seem thus to be more likely to suffer from pollen shortages in smaller habitat fragments. Comparing pollen loads of bumble bees we found that fidelity to V. uliginosum pollen did not depend on plant population size but rather on the extent shrub cover and/or openness of the site. Bumble bees collected pollen only from three plant species (V.uliginosum, Sorbus aucuparia and Cytisus scoparius). We also did not discover any pollination limitation of V. uliginosum in small populations. We conclude that habitat fragmentation might not immediately threaten the pollination of V. uliginosum, nevertheless, it provides important nectar and pollen resources for bumble bees and declining populations of this plant could have negative effects for its pollinators. The finding that large bumble bee species abandon pollen collection when plant populations become small is of interest when considering plant and

  14. No effect of juvenile hormone on task performance in a bumblebee (Bombus terrestris) supports an evolutionary link between endocrine signaling and social complexity.

    PubMed

    Shpigler, Hagai Y; Siegel, Adam J; Huang, Zachary Y; Bloch, Guy

    2016-09-01

    A hallmark of insect societies is a division of labor among workers specializing in different tasks. In bumblebees the division of labor is related to body size; relatively small workers are more likely to stay inside the nest and tend ("nurse") brood, whereas their larger sisters are more likely to forage. Despite their ecological and economic importance, very little is known about the endocrine regulation of division of labor in bumblebees. We studied the influence of juvenile hormone (JH) on task performance in the bumblebee Bombus terrestris. We first used a radioimmunoassay to measure circulating JH titers in workers specializing in nursing and foraging activities. Next, we developed new protocols for manipulating JH titers by combining a size-adjusted topical treatment with the allatotoxin Precocene-I and replacement therapy with JH-III. Finally, we used this protocol to test the influence of JH on task performance. JH levels were either similar for nurses and foragers (three colonies), or higher in nurses (two colonies). Nurses had better developed ovaries and JH levels were typically positively correlated with ovarian state. Manipulation of JH titers influenced ovarian development and wax secretion, consistent with earlier allatectomy studies. These manipulations however, did not affect nursing or foraging activity, or the likelihood to specialize in nursing or foraging activity. These findings contrast with honeybees in which JH influences age-related division of labor but not adult female fertility. Thus, the evolution of complex societies in bees was associated with modifications in the way JH influences social behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Assessment of side-effects by Ludox TMA silica nanoparticles following a dietary exposure on the bumblebee Bombus terrestris.

    PubMed

    Mommaerts, Veerle; Jodko, Katarzyna; Thomassen, Leen C J; Martens, Johan A; Kirsch-Volders, Micheline; Smagghe, Guy

    2012-08-01

    We assessed lethal and sublethal side-effects of Ludox TMA silica nanoparticles on a terrestrial pollinator, Bombus terrestris (Linnaeus), via a dietary exposure. Dynamic light scattering analysis confirmed that silica Ludox TMA nanoparticles remained in suspension in the drinking sugar water. Exposure of bumblebee microcolonies during 7 weeks to the different nanoparticle concentrations (high: 34, 170 and 340 mg/l and low: 34 and 340 μg/l) did not cause worker mortality compared to the controls. Also no effect on the worker foraging behavior was observed after exposure to nanoparticles concentrations up to 340 μg/l. In contrast, the high concentrations (≥34 mg/l) resulted in a total loss of reproduction. Using histological analysis we confirmed severe midgut epithelial injury in intoxicated workers (≥34 mg/l). Despite the fact that these concentrations are much higher than the predicted environmental concentrations, precaution is still needed as information regarding their fate in the terrestrial environment and their potency to bioaccumulate and biomagnificate is lacking.

  16. Preferred viewing directions of bumblebees (Bombus terrestris L.) when learning and approaching their nest site.

    PubMed

    de Ibarra, Natalie Hempel; Philippides, Andrew; Riabinina, Olena; Collett, Thomas S

    2009-10-01

    Many bees and wasps learn about the immediate surroundings of their nest during learning flights, in which they look back towards the nest and acquire visual information that guides their subsequent returns. Visual guidance to the nest is simplified by the insects' tendency to adopt similar viewing directions during learning and return flights. To understand better the factors determining the particular viewing directions that insects choose, we have recorded the learning and return flights of a ground-nesting bumblebee in two visual environments--an enclosed garden with a partly open view between north and west, and a flat roof with a more open panorama. In both places, bees left and returned to an inconspicuous nest hole in the centre of a tabletop, with the hole marked by one or more nearby cylinders. In all experiments, bees adopted similar preferred orientations on their learning and return flights. Bees faced predominantly either north or south, suggesting the existence of two attractors. The bees' selection between attractors seems to be influenced both by the distribution of light, as determined by the shape of the skyline, and by the direction of wind. In the partly enclosed garden with little or no wind, bees tended to face north throughout the day, i.e. towards the pole in the brighter half of their surroundings. When white curtains, which distributed skylight more evenly, were placed around the table, bees faced both north and south. The bees on the roof tended to face south or north when the wind came from a wide arc of directions from the south or north, respectively. We suggest that bees switch facing orientation between north and south as a compromise between maintaining a single viewing direction for efficient view-based navigation and responding to the distribution of light for the easier detection of landmarks seen against the ground or to the direction of the wind for exploiting olfactory cues.

  17. Quantitative Trait Loci for Light Sensitivity, Body Weight, Body Size, and Morphological Eye Parameters in the Bumblebee, Bombus terrestris

    PubMed Central

    Maebe, Kevin; Meeus, Ivan; De Riek, Jan; Smagghe, Guy

    2015-01-01

    Bumblebees such as Bombus terrestris are essential pollinators in natural and managed ecosystems. In addition, this species is intensively used in agriculture for its pollination services, for instance in tomato and pepper greenhouses. Here we performed a quantitative trait loci (QTL) analysis on B. terrestris using 136 microsatellite DNA markers to identify genes linked with 20 traits including light sensitivity, body size and mass, and eye and hind leg measures. By composite interval mapping (IM), we found 83 and 34 suggestive QTLs for 19 of the 20 traits at the linkage group wide significance levels of p = 0.05 and 0.01, respectively. Furthermore, we also found five significant QTLs at the genome wide significant level of p = 0.05. Individual QTLs accounted for 7.5-53.3% of the phenotypic variation. For 15 traits, at least one QTL was confirmed with multiple QTL model mapping. Multivariate principal components analysis confirmed 11 univariate suggestive QTLs but revealed three suggestive QTLs not identified by the individual traits. We also identified several candidate genes linked with light sensitivity, in particular the Phosrestin-1-like gene is a primary candidate for its phototransduction function. In conclusion, we believe that the suggestive and significant QTLs, and markers identified here, can be of use in marker-assisted breeding to improve selection towards light sensitive bumblebees, and thus also the pollination service of bumblebees. PMID:25928544

  18. Quantitative Trait Loci for Light Sensitivity, Body Weight, Body Size, and Morphological Eye Parameters in the Bumblebee, Bombus terrestris.

    PubMed

    Maebe, Kevin; Meeus, Ivan; De Riek, Jan; Smagghe, Guy

    2015-01-01

    Bumblebees such as Bombus terrestris are essential pollinators in natural and managed ecosystems. In addition, this species is intensively used in agriculture for its pollination services, for instance in tomato and pepper greenhouses. Here we performed a quantitative trait loci (QTL) analysis on B. terrestris using 136 microsatellite DNA markers to identify genes linked with 20 traits including light sensitivity, body size and mass, and eye and hind leg measures. By composite interval mapping (IM), we found 83 and 34 suggestive QTLs for 19 of the 20 traits at the linkage group wide significance levels of p = 0.05 and 0.01, respectively. Furthermore, we also found five significant QTLs at the genome wide significant level of p = 0.05. Individual QTLs accounted for 7.5-53.3% of the phenotypic variation. For 15 traits, at least one QTL was confirmed with multiple QTL model mapping. Multivariate principal components analysis confirmed 11 univariate suggestive QTLs but revealed three suggestive QTLs not identified by the individual traits. We also identified several candidate genes linked with light sensitivity, in particular the Phosrestin-1-like gene is a primary candidate for its phototransduction function. In conclusion, we believe that the suggestive and significant QTLs, and markers identified here, can be of use in marker-assisted breeding to improve selection towards light sensitive bumblebees, and thus also the pollination service of bumblebees.

  19. Comparative genetic analyses of historical and contemporary collections highlight contrasting demographic histories for the bumble bees Bombus pensylvanicus and B. impatiens in Illinois.

    PubMed

    Lozier, Jeffrey D; Cameron, Sydney A

    2009-05-01

    Direct comparison of genetic patterns between museum specimens and contemporary collections can be a powerful approach for detecting recent demographic changes. Using microsatellite markers, we examined historical and contemporary genetic variation from an apparently declining bumble bee species, Bombus pensylvanicus, and from a stable species, Bombus impatiens, in central Illinois. For each species, we genotyped specimens from the Illinois Natural History Survey collected from three populations between 1969-1972 and from a resurvey of the same areas conducted in 2008. Population structure in B. pensylvanicus increased markedly over the last four decades (from theta(ST) = 0.001 to 0.027) while no structure was detected in B. impatiens for either time period (theta(ST) = -0.006 to -0.003). Changes in genetic diversity were not significant for either species, although small reductions were observed for B. pensylvanicus in all three populations. Coalescent simulations incorporating both contemporary and historical samples suggest that this small change is not surprising for recent population declines, as large reductions in genetic diversity were only apparent under the most severe bottleneck scenarios. These results demonstrate how comparisons of genetic patterns between temporal periods and species can help elucidate potential threats to population health and suggest several strategies that might be useful in the conservation of B. pensylvanicus in the Midwestern USA.

  20. Location, location, location: larvae position inside the nest is correlated with adult body size in worker bumble-bees (Bombus impatiens)

    PubMed Central

    Couvillon, Margaret J.; Dornhaus, Anna

    2009-01-01

    Social insects display task-related division of labour. In some species, division of labour is related to differences in body size, and worker caste members display morphological adaptations suited for particular tasks. Bumble-bee workers (Bombus spp.) can vary in mass by eight- to tenfold within a single colony, which previous work has linked to division of labour. However, little is known about the proximate mechanism behind the production of this wide range of size variation within the worker caste. Here, we quantify the larval feeding in Bombus impatiens in different nest zones of increasing distance from the centre. There was a significant difference in the number of feedings per larva across zones, with a significant decrease in feeding rates as one moved outwards from the centre of the nest. Likewise, the diameter of the pupae in the peripheral zones was significantly smaller than that of pupae in the centre. Therefore, we conclude that the differential feeding of larvae within a nest, which leads to the size variation within the worker caste, is based on the location of brood clumps. Our work is consistent with the hypothesis that some larvae are ‘forgotten’, providing a possible first mechanism for the creation of size polymorphism in B. impatiens. PMID:19364744

  1. Does the queen win it all? Queen-worker conflict over male production in the bumblebee, Bombus terrestris

    NASA Astrophysics Data System (ADS)

    Alaux, Cédric; Savarit, Fabrice; Jaisson, Pierre; Hefetz, Abraham

    Social insects provide a useful model for studying the evolutionary balance between cooperation and conflict linked to genetic structure. We investigated the outcome of this conflict in the bumblebee, Bombus terrestris, whose annual colony life cycle is characterized by overt competition over male production. We established artificial colonies composed of a queen and unrelated workers by daily exchange of callow workers between colony pairs of distinct genetic make-up. Using microsatellite analysis, this procedure allowed an exact calculation of the proportion of worker-derived males. The development and social behavior of these artificial colonies were similar to those of normal colonies. Despite a high worker reproduction attempt (63.8% of workers had developed ovaries and 38.4% were egg-layers), we found that on average 95% of the males produced during the competition phase (CPh) were queen-derived. However, in four colonies, queen death resulted in a considerable amount of worker-derived male production. The different putative ultimate causes of this efficient control by the queen are discussed, and we suggest a possible scenario of an evolutionary arms race that may occur between these two female castes.

  2. Specific and sensitive detection of Nosema bombi (Microsporidia: Nosematidae) in bumble bees (Bombus spp.; Hymenoptera: Apidae) by PCR of partial rRNA gene sequences.

    PubMed

    Klee, Julia; Tek Tay, Wee; Paxton, Robert J

    2006-02-01

    A polymerase chain reaction (PCR) based method was developed for the specific and sensitive diagnosis of the microsporidian parasite Nosema bombi in bumble bees (Bombus spp.). Four primer pairs, amplifying ribosomal RNA (rRNA) gene fragments, were tested on N. bombi and the related microsporidia Nosema apis and Nosema ceranae, both of which infect honey bees. Only primer pair Nbombi-SSU-Jf1/Jr1 could distinguish N. bombi (323bp amplicon) from these other bee parasites. Primer pairs Nbombi-SSU-Jf1/Jr1 and ITS-f2/r2 were then tested for their sensitivity with N. bombi spore concentrations from 10(7) down to 10 spores diluted in 100 microl of either (i) water or (ii) host bumble bee homogenate to simulate natural N. bombi infection (equivalent to the DNA from 10(6) spores down to 1 spore per PCR). Though the N. bombi-specific primer pair Nbombi-SSU-Jf1/Jr1 was relatively insensitive, as few as 10 spores per extract (equivalent to 1 spore per PCR) were detectable using the N. bombi-non-specific primer pair ITS-f2/r2, which amplifies a short fragment of approximately 120 bp. Testing 99 bumble bees for N. bombi infection by light microscopy versus PCR diagnosis with the highly sensitive primer pair ITS-f2/r2 showed the latter to be more accurate. PCR diagnosis of N. bombi using a combination of two primer pairs (Nbombi-SSU-Jf1/Jr1 and ITS-f2/r2) provides increased specificity, sensitivity, and detection of all developmental stages compared with light microscopy.

  3. Visual targeting of components of floral colour patterns in flower-naïve bumblebees ( Bombus terrestris; Apidae)

    NASA Astrophysics Data System (ADS)

    Lunau, Klaus; Fieselmann, Gabriele; Heuschen, Britta; van de Loo, Antje

    2006-07-01

    Floral colour patterns are contrasting colour patches on flowers, a part of the signalling apparatus that was considered to display shape and colour signals used by flower-visitors to detect flowers and locate the site of floral reward. Here, we show that flower-naïve bumblebees ( Bombus terrestris) spontaneously direct their approach towards the outside margin of artificial flowers, which provides contrast between these dummy flowers and the background. If no floral guides are present, the bumblebees continue to approach the margin and finally touch the marginal area of the dummy flower with the tips of their antennae. Whilst approaching dummy flowers that also have a central floral guide, the bumblebees change their direction of flight: Initially, they approach the margin, later they switch to approaching the colour guide, and finally they precisely touch the floral guide with their antennae. Variation of the shape of equally sized dummy flowers did not alter the bumblebees’ preferential orientation towards the guide. Using reciprocal combinations of guide colour and surrounding colour, we showed that the approach from a distance towards the corolla and the antennal contact with the guide are elicited by the same colour parameter: spectral purity. As a consequence, the dummy flowers eliciting the greatest frequency of antennal reactions at the guide are those that combine a floral guide of high spectral purity with a corolla of less spectral purity. Our results support the hypothesis that floral guides direct bumblebees’ approaches to the site of first contact with the flower, which is achieved by the tips of the antennae.

  4. Separation of different pollen types by chemotactile sensing in Bombus terrestris.

    PubMed

    Ruedenauer, Fabian A; Leonhardt, Sara D; Schmalz, Fabian; Rössler, Wolfgang; Strube-Bloss, Martin F

    2017-04-15

    When tasting food, animals rely on chemical and tactile cues, which determine the animal's decision on whether to eat food. As food nutritional composition has enormous consequences for the survival of animals, food items should generally be tasted before they are eaten or collected for later consumption. Even though recent studies have confirmed the importance of, for example, gustatory cues, compared with olfaction only little is known about the representation of chemotactile stimuli at the receptor level (let alone higher brain centers) in animals other than vertebrates. To better understand how invertebrates may process chemotactile cues, we used bumblebees as a model species and combined electroantennographical (EAG) recordings with a novel technique for chemotactile antennal stimulation in bees. The recorded EAG responses to chemotactile stimulation clearly separated volatile compounds by both compound identity and concentration, and could be successfully applied to test the receptor activity evoked by different types of pollen. We found that two different pollen types (apple and almond; which were readily distinguished by bumblebees in a classical conditioning task) evoked significantly distinct neural activity already at the antennal receptor level. Our novel stimulation technique therefore enables investigation of chemotactile sensing, which is highly important for assessing food nutritional quality while foraging. It can further be applied to test other chemosensory behaviors, such as mate or nest mate recognition, or to investigate whether toxic substances, e.g. in pollen, affect neuronal separation of different food types. © 2017. Published by The Company of Biologists Ltd.

  5. Detoxification and stress response genes expressed in a western North American bumble bee, Bombus huntii (Hymenoptera: Apidae)

    USDA-ARS?s Scientific Manuscript database

    Bumble bees are generalist floral visitors, meaning they pollinate a wide variety of plants. Their pollination activities expose them to both plant toxins and pesticides, yet little is known about what detoxification pathways are active in bumble bees, how the expression of detoxification genes chan...

  6. The effect of group size on the interplay between dominance and reproduction in Bombus terrestris.

    PubMed

    Amsalem, Etya; Hefetz, Abraham

    2011-03-28

    Social insects provide good model systems for testing trade-offs in decision-making because of their marked reproductive skew and the dilemma workers face when to reproduce. Attaining reproductive skew requires energy investment in aggression or fertility signaling, creating a trade-off between reproduction and dominance. This may be density-dependent because the cost of achieving dominance may be higher in larger groups. We investigated the effect of group-size in B. terrestris queenless workers on two major reproduction-dominance correlates: between-worker aggression, and pheromone production, aiming at mimicking decision-making during the transition of worker behavior from cooperation and sterility to aggressive reproductive competition in whole colonies. Despite the competition, reproductive division of labor in colonies can be maintained even during this phase through the production of a sterility signal by sterile workers that has an appeasement effect on dominant nestmates. Worker-worker aggression, ovary activation, and production of sterility-appeasement signals may therefore constitute components of a trade-off affecting worker reproduction decisions. By constructing queenless groups of different size and measuring how this affected the parameters above, we found that in all groups aggression was not evenly distributed with the α-worker performing most of the aggressive acts. Moreover, aggression by the α-worker increased proportionally with group-size. However, while in small groups the α-worker monopolized reproduction, in larger groups several workers shared reproduction, creating two worker groups: reproductives and helpers. It appears that despite the increase of aggression, this was evidently not sufficient for the α-worker to monopolize reproduction. If we compare the α-worker to the queen in full-sized colonies it can be hypothesized that worker reproduction in B. terrestris colonies starts due to a gradual increase in the worker population

  7. Ambient Air Temperature Does Not Predict whether Small or Large Workers Forage in Bumble Bees (Bombus impatiens)

    PubMed Central

    Couvillon, Margaret J.; Fitzpatrick, Ginny; Dornhaus, Anna

    2015-01-01

    Bumble bees are important pollinators of crops and other plants. However, many aspects of their basic biology remain relatively unexplored. For example, one important and unusual natural history feature in bumble bees is the massive size variation seen between workers of the same nest. This size polymorphism may be an adaptation for division of labor, colony economics, or be nonadaptive. It was also suggested that perhaps this variation allows for niche specialization in workers foraging at different temperatures: larger bees might be better suited to forage at cooler temperatures and smaller bees might be better suited to forage at warmer temperatures. This we tested here using a large, enclosed growth chamber, where we were able to regulate the ambient temperature. We found no significant effect of ambient or nest temperature on the average size of bees flying to and foraging from a suspended feeder. Instead, bees of all sizes successfully flew and foraged between 16°C and 36°C. Thus, large bees foraged even at very hot temperatures, which we thought might cause overheating. Size variation therefore could not be explained in terms of niche specialization for foragers at different temperatures. PMID:26005222

  8. Bombus huntii, Bombus impatiens and Bombus vosnesenskii (Hymenoptera: Apidae) pollinate greenhouse-grown tomatoes in western North America

    USDA-ARS?s Scientific Manuscript database

    Bumble bees (Bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared to tomatoes that receive no supplemental pollination. Due to mounting concerns over the transportation of bumble bees outside of their native ranges, several specie...

  9. A scientific note on the comparison of airborne volatiles produced by commercial bumble bee (Bombus impatiens) and honey bee (Apis mellifera) colonies

    USDA-ARS?s Scientific Manuscript database

    Small hive beetles have been documented as being able to successfully invade commercial bumble bee colonies and find the hives through odors produced by the colonies. We tested the hypothesis that volatiles emanating from Bumble bee and Honeybee colonies were similar by collecting volatiles from wo...

  10. Kodamaea ohmeri (Ascomycota: Saccharomycotina) presence in commercial Bombus impatiens Cresson and feral Bombus pensylvanicus DeGeer (Hymenoptera: Apidae) colonies

    USDA-ARS?s Scientific Manuscript database

    In this study, eight commercial and three feral bumble bee (Bombus impatiens Cresson and Bombus pensylvanicus DeGeer respectively, Hymenoptera: Apidae) colonies were tested for the presence of Kodamaea ohmeri (Ascomycota: Saccharomycotina), a yeast known to attract small hive beetles (SHB) (Aethina ...

  11. Monitoring the effects of thiamethoxam applied as a seed treatment to winter oilseed rape on the development of bumblebee (Bombus terrestris) colonies.

    PubMed

    Thompson, Helen; Coulson, Mike; Ruddle, Natalie; Wilkins, Selwyn; Harrington, Paul; Harkin, Sarah

    2016-09-01

    The development of bumblebee (Bombus terrestris audax) colonies that had foraged for 5 weeks on flowering winter oilseed rape grown from seed treated with thiamethoxam (as Cruiser OSR) was assessed (two control, one treated field). Colony development was evaluated by monitoring the colony mass, forager activity was assessed, both at the hive and within the crop, and the contribution of oilseed rape to the pollen stored within the colony was analysed. Pollen collected from the treated crop contained residues of 1.0 µg thiamethoxam kg(-1) and 3.0 µg CGA322704 (metabolite likely equivalent to clothiandin) kg(-1) , and nectar contained residues of 1.8 µg thiamethoxam kg(-1) and no metabolite. No residues of thiamethoxam or CGA322704 were detected in samples from the control fields. Up to 93% of bumblebee collected pollen sampled from within the colonies originated from oilseed rape, and B. terrestris were observed actively foraging on all the fields. Colonies on all three fields showed similar rates of mass gain during the exposure phase and comparable production of gynes and drones. B. terrestris colonies placed adjacent to a field of flowering oilseed rape grown from thiamethoxam-treated seed developed at a comparable rate with colonies placed adjacent to oilseed rape grown from untreated seed. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  12. Flower specialisation: the occluded corolla of snapdragons (Antirrhinum) exhibits two pollinator niches of large long-tongued bees.

    PubMed

    Vargas, P; Liberal, I; Ornosa, C; Gómez, J M

    2017-09-01

    Flower specialisation of angiosperms includes the occluded corollas of snapdragons (Antirrhinum and some relatives), which have been postulated to be one of the most efficient structures to physical limit access to pollinators. The Iberian Peninsula harbours the highest number of species (18 Iberian of the 20 species of Antirrhinum) that potentially share similar pollinator fauna. Crossing experiments with 18 Iberian species from this study and literature revealed a general pattern of self-incompatibility (SI) - failure in this SI system has been also observed in a few plants - which indicates the need for pollinator agents in Antirrhinum pollination. Field surveys in natural conditions (304 h) found flower visitation (>85%) almost exclusively by 11 species of bee (Anthophora fulvitarsis, Anthophora plumipes, Anthidium sticticum, Apis mellifera, Bombus hortorum, Bombus pascuorum, Bombus ruderatus, Bombus terrestris, Chalicodoma lefebvrei, Chalicodoma pyrenaica and Xylocopa violacea). This result covering the majority of Antirrhinum species suggests that large bees of the two long-tongued bee families (Megachilidae, Apidae) are the major pollinators of Antirrhinum. A bipartite modularity analysis revealed two pollinator systems of long-tongued bees: (i) the long-studied system of bumblebees (Bombus spp.) associated with nine primarily northern species of Antirrhinum; and (ii) a newly proposed pollinator system involving other large bees associated with seven species primarily distributed in southern Mediterranean areas. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  13. Bumblebee calligraphy: the design and control of flight motifs in the learning and return flights of Bombus terrestris.

    PubMed

    Philippides, Andrew; de Ibarra, Natalie Hempel; Riabinina, Olena; Collett, Thomas S

    2013-03-15

    Many wasps and bees learn the position of their nest relative to nearby visual features during elaborate 'learning' flights that they perform on leaving the nest. Return flights to the nest are thought to be patterned so that insects can reach their nest by matching their current view to views of their surroundings stored during learning flights. To understand how ground-nesting bumblebees might implement such a matching process, we have video-recorded the bees' learning and return flights and analysed the similarities and differences between the principal motifs of their flights. Loops that take bees away from and bring them back towards the nest are common during learning flights and less so in return flights. Zigzags are more prominent on return flights. Both motifs tend to be nest based. Bees often both fly towards and face the nest in the middle of loops and at the turns of zigzags. Before and after flight direction and body orientation are aligned, the two diverge from each other so that the nest is held within the bees' fronto-lateral visual field while flight direction relative to the nest can fluctuate more widely. These and other parallels between loops and zigzags suggest that they are stable variations of an underlying pattern, which enable bees to store and reacquire similar nest-focused views during learning and return flights.

  14. Bombus huntii, Bombus impatiens, and Bombus vosnesenskii (Hymenoptera: Apidae) Pollinate Greenhouse-Grown Tomatoes in Western North America.

    PubMed

    Strange, James P

    2015-06-01

    Bumble bees (Bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared with tomatoes that receive no supplemental pollination. More than a million colonies are sold worldwide annually to meet pollination needs. Due to mounting concerns over the transportation of bumble bees outside of their native ranges, several species native to western North American are currently being investigated as potential commercial pollinators. Here, two western, Bombus huntii Greene and Bombus vosnesenskii Radoszkowski, and one eastern species, Bombus impatiens Cresson, are compared for their efficacy as pollinators of greenhouse-grown tomatoes. In two experiments, colonies were placed in greenhouses and compared with control plants that received no supplemental pollination. In the first experiment, seed set was significantly increased with B. huntii pollination in one variety of cherry tomatoes. In the second experiment comparing all three bumble bee species, fruit weight was an average of 25.2 g heavier per fruit pollinated by bees versus the control, and the number of days to harvest was 2.9 d shorter for bee-pollinated fruit. In some rounds of pollination, differences were found among bumble bee species, but these were inconsistent across replicates and not statistically significant overall. Additionally, fruit weight was shown to be highly correlated to fruit diameter and seed set in all tests and, thus, is shown to be a reliable metric for assessing pollination in future studies. These results suggest that commercialization of western bumble bees is a viable alternative to the current practices of moving of nonnative bees into western North America to pollinate tomatoes.

  15. Differential sensitivity of honey bees and bumble bees to a dietary insecticide (imidacloprid).

    PubMed

    Cresswell, James E; Page, Christopher J; Uygun, Mehmet B; Holmbergh, Marie; Li, Yueru; Wheeler, Jonathan G; Laycock, Ian; Pook, Christopher J; de Ibarra, Natalie Hempel; Smirnoff, Nick; Tyler, Charles R

    2012-12-01

    Currently, there is concern about declining bee populations and the sustainability of pollination services. One potential threat to bees is the unintended impact of systemic insecticides, which are ingested by bees in the nectar and pollen from flowers of treated crops. To establish whether imidacloprid, a systemic neonicotinoid and insect neurotoxin, harms individual bees when ingested at environmentally realistic levels, we exposed adult worker bumble bees, Bombus terrestris L. (Hymenoptera: Apidae), and honey bees, Apis mellifera L. (Hymenoptera: Apidae), to dietary imidacloprid in feeder syrup at dosages between 0.08 and 125μg l(-1). Honey bees showed no response to dietary imidacloprid on any variable that we measured (feeding, locomotion and longevity). In contrast, bumble bees progressively developed over time a dose-dependent reduction in feeding rate with declines of 10-30% in the environmentally relevant range of up to 10μg l(-1), but neither their locomotory activity nor longevity varied with diet. To explain their differential sensitivity, we speculate that honey bees are better pre-adapted than bumble bees to feed on nectars containing synthetic alkaloids, such as imidacloprid, by virtue of their ancestral adaptation to tropical nectars in which natural alkaloids are prevalent. We emphasise that our study does not suggest that honey bee colonies are invulnerable to dietary imidacloprid under field conditions, but our findings do raise new concern about the impact of agricultural neonicotinoids on wild bumble bee populations. Copyright © 2012 Elsevier GmbH. All rights reserved.

  16. Bumblebees (Bombus terrestris) and honeybees (Apis mellifera) prefer similar colours of higher spectral purity over trained colours.

    PubMed

    Rohde, Katja; Papiorek, Sarah; Lunau, Klaus

    2013-03-01

    Differences in the concentration of pigments as well as their composition and spatial arrangement cause intraspecific variation in the spectral signature of flowers. Known colour preferences and requirements for flower-constant foraging bees predict different responses to colour variability. In experimental settings, we simulated small variations of unicoloured petals and variations in the spatial arrangement of colours within tricoloured petals using artificial flowers and studied their impact on the colour choices of bumblebees and honeybees. Workers were trained to artificial flowers of a given colour and then given the simultaneous choice between three test colours: either the training colour, one colour of lower and one of higher spectral purity, or the training colour, one colour of lower and one of higher dominant wavelength; in all cases the perceptual contrast between the training colour and the additional test colours was similarly small. Bees preferred artificial test flowers which resembled the training colour with the exception that they preferred test colours with higher spectral purity over trained colours. Testing the behaviour of bees at artificial flowers displaying a centripetal or centrifugal arrangement of three equally sized colours with small differences in spectral purity, bees did not prefer any type of artificial flowers, but preferentially choose the most spectrally pure area for the first antenna contact at both types of artificial flowers. Our results indicate that innate preferences for flower colours of high spectral purity in pollinators might exert selective pressure on the evolution of flower colours.

  17. Country-specific effects of neonicotinoid pesticides on honey bees and wild bees.

    PubMed

    Woodcock, B A; Bullock, J M; Shore, R F; Heard, M S; Pereira, M G; Redhead, J; Ridding, L; Dean, H; Sleep, D; Henrys, P; Peyton, J; Hulmes, S; Hulmes, L; Sárospataki, M; Saure, C; Edwards, M; Genersch, E; Knäbe, S; Pywell, R F

    2017-06-30

    Neonicotinoid seed dressings have caused concern world-wide. We use large field experiments to assess the effects of neonicotinoid-treated crops on three bee species across three countries (Hungary, Germany, and the United Kingdom). Winter-sown oilseed rape was grown commercially with either seed coatings containing neonicotinoids (clothianidin or thiamethoxam) or no seed treatment (control). For honey bees, we found both negative (Hungary and United Kingdom) and positive (Germany) effects during crop flowering. In Hungary, negative effects on honey bees (associated with clothianidin) persisted over winter and resulted in smaller colonies in the following spring (24% declines). In wild bees (Bombus terrestris and Osmia bicornis), reproduction was negatively correlated with neonicotinoid residues. These findings point to neonicotinoids causing a reduced capacity of bee species to establish new populations in the year following exposure. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  18. Israeli Acute Paralysis Virus Infection Leads to an Enhanced RNA Interference Response and Not Its Suppression in the Bumblebee Bombus terrestris

    PubMed Central

    Cappelle, Kaat; Smagghe, Guy; Dhaenens, Maarten; Meeus, Ivan

    2016-01-01

    RNA interference (RNAi) is the primary antiviral defense system in insects and its importance for pollinator health is indisputable. In this work, we examined the effect of Israeli acute paralysis virus (IAPV) infection on the RNAi process in the bumblebee, Bombus terrestris, and whether the presence of possible functional viral suppressors could alter the potency of the host’s immune response. For this, a two-fold approach was used. Through a functional RNAi assay, we observed an enhancement of the RNAi system after IAPV infection instead of its suppression, despite only minimal upregulation of the genes involved in RNAi. Besides, the presence of the proposed suppressor 1A and the predicted OrfX protein in IAPV could not be confirmed using high definition mass spectrometry. In parallel, when bumblebees were infected with cricket paralysis virus (CrPV), known to encode a suppressor of RNAi, no increase in RNAi efficiency was seen. For both viruses, pre-infection with the one virus lead to a decreased replication of the other virus, indicating a major effect of competition. These results are compelling in the context of Dicistroviridae in multi-virus/multi-host networks as the effect of a viral infection on the RNAi machinery may influence subsequent virus infections. PMID:27999371

  19. Israeli Acute Paralysis Virus Infection Leads to an Enhanced RNA Interference Response and Not Its Suppression in the Bumblebee Bombus terrestris.

    PubMed

    Cappelle, Kaat; Smagghe, Guy; Dhaenens, Maarten; Meeus, Ivan

    2016-12-19

    RNA interference (RNAi) is the primary antiviral defense system in insects and its importance for pollinator health is indisputable. In this work, we examined the effect of Israeli acute paralysis virus (IAPV) infection on the RNAi process in the bumblebee, Bombus terrestris, and whether the presence of possible functional viral suppressors could alter the potency of the host's immune response. For this, a two-fold approach was used. Through a functional RNAi assay, we observed an enhancement of the RNAi system after IAPV infection instead of its suppression, despite only minimal upregulation of the genes involved in RNAi. Besides, the presence of the proposed suppressor 1A and the predicted OrfX protein in IAPV could not be confirmed using high definition mass spectrometry. In parallel, when bumblebees were infected with cricket paralysis virus (CrPV), known to encode a suppressor of RNAi, no increase in RNAi efficiency was seen. For both viruses, pre-infection with the one virus lead to a decreased replication of the other virus, indicating a major effect of competition. These results are compelling in the context of Dicistroviridae in multi-virus/multi-host networks as the effect of a viral infection on the RNAi machinery may influence subsequent virus infections.

  20. Nutrient enrichment is associated with altered nectar and pollen chemical composition in Succisa pratensis Moench and increased larval mortality of its pollinator Bombus terrestris L.

    PubMed

    Ceulemans, Tobias; Hulsmans, Eva; Vanden Ende, Wim; Honnay, Olivier

    2017-01-01

    Pollinators are declining worldwide and possible underlying causes include disease, invasive pest species and large scale land use changes resulting in habitat loss and degradation. One particular cause of habitat degradation is the increased inflow of nutrients due to anthropogenic combustion processes and large scale application of agricultural fertilizers. This nutrient pollution has been shown to affect pollinators through the loss of nectar and pollen-providing plant species. However, it may also affect pollinators through altering the nectar and pollen chemical composition of plant species, hence influencing pollinator food quality. Here, we experimentally investigated the effect of nutrient enrichment on amino acid and sugar composition of nectar and pollen in the grassland plant Sucissa pratensis, and the subsequent colony size and larval mortality of the pollinating bumblebee Bombus terrestris. We found less of the essential amino acids glycine and arginine in the pollen of fertilized plants, and more arginine, ornithine and threonine in the pollen of control plants. Nectar glucose and pollen fructose levels were lower in fertilized plants as compared to control plants. Furthermore, bumblebee colonies visiting fertilized plants showed more dead larvae than colonies visiting control plants. Our results suggest that the fitness of bumblebees can be negatively affected by changes in their food quality following nutrient pollution. If similar patterns hold for other plant and pollinator species, this may have far reaching implications for the maintenance of pollination ecosystem services, as nutrient pollution continues to rise worldwide.

  1. Gene Expression Dynamics in Major Endocrine Regulatory Pathways along the Transition from Solitary to Social Life in a Bumblebee, Bombus terrestris

    PubMed Central

    Jedlička, Pavel; Ernst, Ulrich R.; Votavová, Alena; Hanus, Robert; Valterová, Irena

    2016-01-01

    Understanding the social evolution leading to insect eusociality requires, among other, a detailed insight into endocrine regulatory mechanisms that have been co-opted from solitary ancestors to play new roles in the complex life histories of eusocial species. Bumblebees represent well-suited models of a relatively primitive social organization standing on the mid-way to highly advanced eusociality and their queens undergo both, a solitary and a social phase, separated by winter diapause. In the present paper, we characterize the gene expression levels of major endocrine regulatory pathways across tissues, sexes, and life-stages of the buff-tailed bumblebee, Bombus terrestris, with special emphasis on critical stages of the queen's transition from solitary to social life. We focused on fundamental genes of three pathways: (1) Forkhead box protein O and insulin/insulin-like signaling, (2) Juvenile hormone (JH) signaling, and (3) Adipokinetic hormone signaling. Virgin queens were distinguished by higher expression of forkhead box protein O and downregulated insulin-like peptides and JH signaling, indicated by low expression of methyl farnesoate epoxidase (MFE) and transcription factor Krüppel homolog 1 (Kr-h1). Diapausing queens showed the expected downregulation of JH signaling in terms of low MFE and vitellogenin (Vg) expressions, but an unexpectedly high expression of Kr-h1. By contrast, reproducing queens revealed an upregulation of MFE and Vg together with insulin signaling. Surprisingly, the insulin growth factor 1 (IGF-1) turned out to be a queen-specific hormone. Workers exhibited an expression pattern of MFE and Vg similar to that of reproducing queens. Males were characterized by high Kr-h1 expression and low Vg level. The tissue comparison unveiled an unexpected resemblance between the fat body and hypopharyngeal glands across all investigated genes, sexes, and life stages. PMID:27932998

  2. Bumble bees regulate their intake of essential protein and lipid pollen macronutrients.

    PubMed

    Vaudo, A D; Stabler, D; Patch, H M; Tooker, J F; Grozinger, C M; Wright, G A

    2016-12-15

    Bee population declines are linked to the reduction of nutritional resources due to land-use intensification, yet we know little about the specific nutritional needs of many bee species. Pollen provides bees with their primary source of protein and lipids, but nutritional quality varies widely among host-plant species. Therefore, bees might have adapted to assess resource quality and adjust their foraging behavior to balance nutrition from multiple food sources. We tested the ability of two bumble bee species, Bombus terrestris and Bombus impatiens, to regulate protein and lipid intake. We restricted B. terrestris adults to single synthetic diets varying in protein:lipid ratios (P:L). The bees over-ate protein on low-fat diets and over-ate lipid on high-fat diets to reach their targets of lipid and protein, respectively. The bees survived best on a 10:1 P:L diet; the risk of dying increased as a function of dietary lipid when bees ate diets with lipid contents greater than 5:1 P:L. Hypothesizing that the P:L intake target of adult worker bumble bees was between 25:1 and 5:1, we presented workers from both species with unbalanced but complementary paired diets to determine whether they self-select their diet to reach a specific intake target. Bees consumed similar amounts of proteins and lipids in each treatment and averaged a 14:1 P:L for B. terrestris and 12:1 P:L for B. impatiens These results demonstrate that adult worker bumble bees likely select foods that provide them with a specific ratio of P:L. These P:L intake targets could affect pollen foraging in the field and help explain patterns of host-plant species choice by bumble bees.

  3. PCR reveals high prevalence of non-sporulating Nosema bombi(Microsporidia) infections in bumble bees (Bombus)in northern Arizona

    USDA-ARS?s Scientific Manuscript database

    About 20% of bumble bee species are in decline in North America, and the microsporidian pathogen, Nosema bombi, may be a factor in these declines. We performed a comprehensive survey of N. bombi infections in the bumble bee communities throughout the flight season along an elevation gradient in Nort...

  4. Bees prefer foods containing neonicotinoid pesticides

    NASA Astrophysics Data System (ADS)

    Kessler, Sébastien C.; Tiedeken, Erin Jo; Simcock, Kerry L.; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Stout, Jane C.; Wright, Geraldine A.

    2015-05-01

    The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO), in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX and CLO neither elicited spiking responses from gustatory neurons in the bees' mouthparts, nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX, even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a sizeable hazard to foraging bees.

  5. Bees prefer foods containing neonicotinoid pesticides.

    PubMed

    Kessler, Sébastien C; Tiedeken, Erin Jo; Simcock, Kerry L; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Radcliffe, Amy; Stout, Jane C; Wright, Geraldine A

    2015-05-07

    The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO), in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX and CLO neither elicited spiking responses from gustatory neurons in the bees' mouthparts, nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX, even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a sizeable hazard to foraging bees.

  6. Bees prefer foods containing neonicotinoid pesticides

    PubMed Central

    Simcock, Kerry L.; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Stout, Jane C.; Wright, Geraldine A.

    2015-01-01

    The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies1-3. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants4. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure4,5. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly-used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO) in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX, and CLO neither elicited spiking responses from gustatory neurons in the bees’ mouthparts nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a significant hazard to foraging bees. PMID:25901684

  7. Unbiased RNA Shotgun Metagenomics in Social and Solitary Wild Bees Detects Associations with Eukaryote Parasites and New Viruses

    PubMed Central

    De Smet, Lina; Smagghe, Guy; Vierstraete, Andy; Braeckman, Bart P.; de Graaf, Dirk C.

    2016-01-01

    The diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, Apis mellifera. Using a deliberate RNA shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, Bombus terrestris and Bombus pascuorum, and two solitary bee hosts, Osmia cornuta and Andrena vaga. Ion Torrent semiconductor sequencing generated approximately 3.8 million high quality reads. The most significant eukaryote associations were two protozoan, Apicystis bombi and Crithidia bombi, and one nematode parasite Sphaerularia bombi in bumble bees. The trypanosome protozoan C. bombi was also found in the solitary bee O. cornuta. Next to the identification of three honey bee viruses Black queen cell virus, Sacbrood virus and Varroa destructor virus-1 and four plant viruses, we describe two novel RNA viruses Scaldis River bee virus (SRBV) and Ganda bee virus (GABV) based on their partial genomic sequences. The novel viruses belong to the class of negative-sense RNA viruses, SRBV is related to the order Mononegavirales whereas GABV is related to the family Bunyaviridae. The potential biological role of both viruses in bees is discussed in the context of recent advances in the field of arthropod viruses. Further, fragmentary sequence evidence for other undescribed viruses is presented, among which a nudivirus in O. cornuta and an unclassified virus related to Chronic bee paralysis virus in B. terrestris. Our findings extend the current knowledge of wild bee parasites in general and addsto the growing evidence of unexplored arthropod viruses in valuable insects. PMID:28006002

  8. Unbiased RNA Shotgun Metagenomics in Social and Solitary Wild Bees Detects Associations with Eukaryote Parasites and New Viruses.

    PubMed

    Schoonvaere, Karel; De Smet, Lina; Smagghe, Guy; Vierstraete, Andy; Braeckman, Bart P; de Graaf, Dirk C

    2016-01-01

    The diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, Apis mellifera. Using a deliberate RNA shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, Bombus terrestris and Bombus pascuorum, and two solitary bee hosts, Osmia cornuta and Andrena vaga. Ion Torrent semiconductor sequencing generated approximately 3.8 million high quality reads. The most significant eukaryote associations were two protozoan, Apicystis bombi and Crithidia bombi, and one nematode parasite Sphaerularia bombi in bumble bees. The trypanosome protozoan C. bombi was also found in the solitary bee O. cornuta. Next to the identification of three honey bee viruses Black queen cell virus, Sacbrood virus and Varroa destructor virus-1 and four plant viruses, we describe two novel RNA viruses Scaldis River bee virus (SRBV) and Ganda bee virus (GABV) based on their partial genomic sequences. The novel viruses belong to the class of negative-sense RNA viruses, SRBV is related to the order Mononegavirales whereas GABV is related to the family Bunyaviridae. The potential biological role of both viruses in bees is discussed in the context of recent advances in the field of arthropod viruses. Further, fragmentary sequence evidence for other undescribed viruses is presented, among which a nudivirus in O. cornuta and an unclassified virus related to Chronic bee paralysis virus in B. terrestris. Our findings extend the current knowledge of wild bee parasites in general and addsto the growing evidence of unexplored arthropod viruses in valuable insects.

  9. From silkworms to bees: Diseases of beneficial insects

    USDA-ARS?s Scientific Manuscript database

    The diseases of the silkworm (Bombyx mori) and managed bees, including the honey bee (Apis mellifera), bumbles bees (Bombus spp.), the alfalfa leafcutting bee (Megachile rotundata), and mason bees (Osmia spp.) are reviewed, with diagnostic descriptions and a summary of control methods for production...

  10. Historical changes in northeastern US bee pollinators related to shared ecological traits

    PubMed Central

    Bartomeus, Ignasi; Ascher, John S.; Gibbs, Jason; Danforth, Bryan N.; Wagner, David L.; Hedtke, Shannon M.; Winfree, Rachael

    2013-01-01

    Pollinators such as bees are essential to the functioning of terrestrial ecosystems. However, despite concerns about a global pollinator crisis, long-term data on the status of bee species are limited. We present a long-term study of relative rates of change for an entire regional bee fauna in the northeastern United States, based on >30,000 museum records representing 438 species. Over a 140-y period, aggregate native species richness weakly decreased, but richness declines were significant only for the genus Bombus. Of 187 native species analyzed individually, only three declined steeply, all of these in the genus Bombus. However, there were large shifts in community composition, as indicated by 56% of species showing significant changes in relative abundance over time. Traits associated with a declining relative abundance include small dietary and phenological breadth and large body size. In addition, species with lower latitudinal range boundaries are increasing in relative abundance, a finding that may represent a response to climate change. We show that despite marked increases in human population density and large changes in anthropogenic land use, aggregate native species richness declines were modest outside of the genus Bombus. At the same time, we find that certain ecological traits are associated with declines in relative abundance. These results should help target conservation efforts focused on maintaining native bee abundance and diversity and therefore the important ecosystems services that they provide. PMID:23487768

  11. Historical changes in northeastern US bee pollinators related to shared ecological traits.

    PubMed

    Bartomeus, Ignasi; Ascher, John S; Gibbs, Jason; Danforth, Bryan N; Wagner, David L; Hedtke, Shannon M; Winfree, Rachael

    2013-03-19

    Pollinators such as bees are essential to the functioning of terrestrial ecosystems. However, despite concerns about a global pollinator crisis, long-term data on the status of bee species are limited. We present a long-term study of relative rates of change for an entire regional bee fauna in the northeastern United States, based on >30,000 museum records representing 438 species. Over a 140-y period, aggregate native species richness weakly decreased, but richness declines were significant only for the genus Bombus. Of 187 native species analyzed individually, only three declined steeply, all of these in the genus Bombus. However, there were large shifts in community composition, as indicated by 56% of species showing significant changes in relative abundance over time. Traits associated with a declining relative abundance include small dietary and phenological breadth and large body size. In addition, species with lower latitudinal range boundaries are increasing in relative abundance, a finding that may represent a response to climate change. We show that despite marked increases in human population density and large changes in anthropogenic land use, aggregate native species richness declines were modest outside of the genus Bombus. At the same time, we find that certain ecological traits are associated with declines in relative abundance. These results should help target conservation efforts focused on maintaining native bee abundance and diversity and therefore the important ecosystems services that they provide.

  12. Varroa destructor Macula-like virus, Lake Sinai virus and other new RNA viruses in wild bumblebee hosts (Bombus pascuorum, Bombus lapidarius and Bombus pratorum).

    PubMed

    Parmentier, Laurian; Smagghe, Guy; de Graaf, Dirk C; Meeus, Ivan

    2016-02-01

    Pollinators such as bumblebees (Bombus spp.) are in decline worldwide which poses a threat not only for ecosystem biodiversity but also to human crop production services. One main cause of pollinator decline may be the infection and transmission of diseases including RNA viruses. Recently, new viruses have been discovered in honeybees, but information on the presence of these in wild bumblebees is largely not available. In this study, we investigated the prevalence of new RNA viruses in Bombus species, and can report for the first time Varroa destructor Macula-like virus (VdMLV) and Lake Sinai virus (LSV) infection in multiple wild bumblebee hosts of Bombus pascuorum, Bombus lapidarius and Bombus pratorum. We sampled in 4 locations in Flanders, Belgium. Besides, we confirmed Slow bee paralysis virus (SBPV) in wild bumblebees, but no positive samples were obtained for Big Sioux river virus (BSRV). Secondly, we screened for the influence of apiaries on the prevalence of these viruses. Our results indicated a location effect for the prevalence of VdMLV in Bombus species, with a higher prevalence in the proximity of honeybee apiaries mainly observed in one location. For LSV, the prevalence was not different in the proximity or at a 1.5 km-distance of apiaries, but we reported a different isolate with similarities to LSV-2 and "LSV-clade A" as described by Ravoet et al. (2015), which was detected both in Apis mellifera and Bombus species. In general, our results indicate the existence of a disease pool of new viruses that seems to be associated to a broad range of Apoidae hosts, including multiple Bombus species. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. The status of Bombus occidentalis and B. moderatus in Alaska with special focus on Nosema bombi incidence

    USDA-ARS?s Scientific Manuscript database

    Technical Abstract: Four North American bumble bee species in the subgenus Bombus sensu stricto, including Bombus occidentalis (Hymenoptera: Apidae), are experiencing dramatic declines in population abundance, range and genetic diversity. The prevailing hypothesis concerning their decline is the ‘s...

  14. Interspecific sensitivity of bees towards dimethoate and implications for environmental risk assessment

    PubMed Central

    Uhl, Philipp; Franke, Lea A.; Rehberg, Christina; Wollmann, Claudia; Stahlschmidt, Peter; Jeker, Lukas; Brühl, Carsten A.

    2016-01-01

    Wild and domesticated bee species are exposed to a variety of pesticides which may drive pollinator decline. Due to wild bee sensitivity data shortage, it is unclear if the honey bee Apis mellifera is a suitable surrogate species in the current EU risk assessment scheme. Furthermore, the underlying causes for sensitivity differences in bees are not established. We assessed the acute toxicity (median lethal dose, LD50) of dimethoate towards multiple bee species, generated a species sensitivity distribution and derived a hazardous dose (HD5). Furthermore, we performed a regression analysis with body weight and dimethoate toxicity. HD5 lower 95% confidence limit was equal to honey bee mean LD50 when applying a safety factor of 10. Body weight proved to be a predictor of interspecific bee sensitivity but did not explain the pattern completely. Using acute toxicity values from honey bees and a safety factor of 10 seems to cover the interspecific sensitivity range of bees in the case of dimethoate. Acute endpoints of proposed additional test species, the buff-tailed bumblebee Bombus terrestris and the red mason bee Osmia bicornis, do not improve the risk assessment for the entire group. However, this might not apply to other insecticides such as neonicotinoids. PMID:27686060

  15. Interspecific sensitivity of bees towards dimethoate and implications for environmental risk assessment.

    PubMed

    Uhl, Philipp; Franke, Lea A; Rehberg, Christina; Wollmann, Claudia; Stahlschmidt, Peter; Jeker, Lukas; Brühl, Carsten A

    2016-09-30

    Wild and domesticated bee species are exposed to a variety of pesticides which may drive pollinator decline. Due to wild bee sensitivity data shortage, it is unclear if the honey bee Apis mellifera is a suitable surrogate species in the current EU risk assessment scheme. Furthermore, the underlying causes for sensitivity differences in bees are not established. We assessed the acute toxicity (median lethal dose, LD50) of dimethoate towards multiple bee species, generated a species sensitivity distribution and derived a hazardous dose (HD5). Furthermore, we performed a regression analysis with body weight and dimethoate toxicity. HD5 lower 95% confidence limit was equal to honey bee mean LD50 when applying a safety factor of 10. Body weight proved to be a predictor of interspecific bee sensitivity but did not explain the pattern completely. Using acute toxicity values from honey bees and a safety factor of 10 seems to cover the interspecific sensitivity range of bees in the case of dimethoate. Acute endpoints of proposed additional test species, the buff-tailed bumblebee Bombus terrestris and the red mason bee Osmia bicornis, do not improve the risk assessment for the entire group. However, this might not apply to other insecticides such as neonicotinoids.

  16. Diversity of Nosema associated with bumblebees (Bombus spp.) from China.

    PubMed

    Li, Jilian; Chen, Wenfeng; Wu, Jie; Peng, Wenjun; An, Jiandong; Schmid-Hempel, Paul; Schmid-Hempel, Regula

    2012-01-01

    Bumblebees (Bombus spp.) are important pollinators of many economically important crops and microsporidia are among the most important infections of these hosts. Using molecular markers, we screened a large sample (n=1,009 bees) of workers of 27 different Bombus spp. from China (Sichuan, Qinghai, Inner Mongolia, and Gansu provinces). The results showed that 62 individuals representing 12 Bombus spp. were infected by microsporidia with an overall prevalence of 6.1%. Based on the haplotypes (ssrRNA sequences), we confirmed the presence of Nosema bombi, Nosema ceranae and (likely) Nosema thomsoni. In addition, four new putatively novel taxa were identified by phylogenetic reconstruction: Nosema A, Nosema B-complex, Nosema C-complex and Nosema D-complex. In many cases, hosts were infected by more than one Nosema taxon. Possible caveats of sequence analyses are discussed. Copyright © 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  17. Infections of virulent and avirulent viruses differentially influenced the expression of dicer-1, ago-1, and microRNAs in Bombus terrestris

    PubMed Central

    Niu, Jinzhi; Meeus, Ivan; De Coninck, Dieter IM; Deforce, Dieter; Etebari, Kayvan; Asgari, Sassan; Smagghe, Guy

    2017-01-01

    The microRNA (miRNA) pathway is well established to be involved in host-pathogen interactions. As key insect pollinators, bees are suffering from widely spreading viruses, especially honeybees and bumblebees. In order to better understand bee-virus interaction, we comparatively analyzed the involvement of the bumblebee miRNA pathway upon infection by two different viruses. In our setup, an avirulent infection is induced by slow bee paralysis virus (SBPV) and a virulent infection is induced by Israeli acute paralysis virus (IAPV). Our results showed the increased expressions of dicer-1 and ago-1 upon SBPV infection. There were 17 and 12 bumblebee miRNAs differentially expressed upon SBPV and IAPV infections, respectively. These results may indicate the involvement of the host miRNA pathway in bumblebee-virus interaction. However, silencing of dicer-1 did not influence the genome copy number of SBPV. Target prediction for these differentially expressed miRNAs showed their possible involvement in targeting viral genomic RNA and in the regulation of networks in bumblebee. Our study opens a new insight into bee-virus interaction meditated by host miRNAs. PMID:28374846

  18. Infections of virulent and avirulent viruses differentially influenced the expression of dicer-1, ago-1, and microRNAs in Bombus terrestris.

    PubMed

    Niu, Jinzhi; Meeus, Ivan; De Coninck, Dieter Im; Deforce, Dieter; Etebari, Kayvan; Asgari, Sassan; Smagghe, Guy

    2017-04-04

    The microRNA (miRNA) pathway is well established to be involved in host-pathogen interactions. As key insect pollinators, bees are suffering from widely spreading viruses, especially honeybees and bumblebees. In order to better understand bee-virus interaction, we comparatively analyzed the involvement of the bumblebee miRNA pathway upon infection by two different viruses. In our setup, an avirulent infection is induced by slow bee paralysis virus (SBPV) and a virulent infection is induced by Israeli acute paralysis virus (IAPV). Our results showed the increased expressions of dicer-1 and ago-1 upon SBPV infection. There were 17 and 12 bumblebee miRNAs differentially expressed upon SBPV and IAPV infections, respectively. These results may indicate the involvement of the host miRNA pathway in bumblebee-virus interaction. However, silencing of dicer-1 did not influence the genome copy number of SBPV. Target prediction for these differentially expressed miRNAs showed their possible involvement in targeting viral genomic RNA and in the regulation of networks in bumblebee. Our study opens a new insight into bee-virus interaction meditated by host miRNAs.

  19. Landscape Scale Study of the Net Effect of Proximity to a Neonicotinoid-Treated Crop on Bee Colony Health.

    PubMed

    Balfour, Nicholas J; Al Toufailia, Hasan; Scandian, Luciano; Blanchard, Héloïse E; Jesse, Matthew P; Carreck, Norman L; Ratnieks, Francis L W

    2017-09-19

    Since 2013, the European Commission has restricted the use of three neonicotinoid insecticides as seed dressings on bee-attractive crops. Such crops represent an important source of forage for bees, which is often scarce in agro-ecosystems. However, this benefit has often been overlooked in the design of previous field studies, leaving the net impact of neonicotinoid treated crops on bees relatively unknown. Here, we determine the combined benefit (forage) and cost (insecticide) of oilseed rape grown from thiamethoxam-treated seeds on Bombus terrestris and Apis mellifera colonies. In April 2014, 36 colonies per species were located adjacent to three large oilseed rape fields (12 colonies per field). Another 36 were in three nearby locations in the same agro-ecosystem, but several kilometers distant from any oilseed rape fields. We found that Bombus colony growth and reproduction were unaffected by location (distant versus adjacent) following the two month flowering period. Apis colony and queen survival were unaffected. However, there was a small, but significant, negative relationship between honey and pollen neonicotinoid contamination and Apis colony weight gain. We hypothesize that any sublethal effects of neonicotinoid seed dressings on Bombus colonies are potentially offset by the additional foraging resources provided. A better understanding of the ecological and agronomic factors underlying neonicotinoid residues is needed to inform evidence-based policy.

  20. Lethal and sublethal effects, and incomplete clearance of ingested imidacloprid in honey bees (Apis mellifera).

    PubMed

    Sánchez-Bayo, Francisco; Belzunces, Luc; Bonmatin, Jean-Marc

    2017-08-22

    A previous study claimed a differential behavioural resilience between spring or summer honey bees (Apis mellifera) and bumble bees (Bombus terrestris) after exposure to syrup contaminated with 125 µg L(-1) imidacloprid for 8 days. The authors of that study based their assertion on the lack of body residues and toxic effects in honey bees, whereas bumble bees showed body residues of imidacloprid and impaired locomotion during the exposure. We have reproduced their experiment using winter honey bees subject to the same protocol. After exposure to syrup contaminated with 125 µg L(-1) imidacloprid, honey bees experienced high mortality rates (up to 45%), had body residues of imidacloprid in the range 2.7-5.7 ng g(-1) and exhibited abnormal behaviours (restless, apathetic, trembling and falling over) that were significantly different from the controls. There was incomplete clearance of the insecticide during the 10-day exposure period. Our results contrast with the findings reported in the previous study for spring or summer honey bees, but are consistent with the results reported for the other bee species.

  1. Phylogenetic analysis of honey bee behavioral evolution.

    PubMed

    Raffiudin, Rika; Crozier, Ross H

    2007-05-01

    DNA sequences from three mitochondrial (rrnL, cox2, nad2) and one nuclear gene (itpr) from all 9 known honey bee species (Apis), a 10th possible species, Apis dorsata binghami, and three outgroup species (Bombus terrestris, Melipona bicolor and Trigona fimbriata) were used to infer Apis phylogenetic relationships using Bayesian analysis. The dwarf honey bees were confirmed as basal, and the giant and cavity-nesting species to be monophyletic. All nodes were strongly supported except that grouping Apis cerana with A. nigrocincta. Two thousand post-burnin trees from the phylogenetic analysis were used in a Bayesian comparative analysis to explore the evolution of dance type, nest structure, comb structure and dance sound within Apis. The ancestral honey bee species was inferred with high support to have nested in the open, and to have more likely than not had a silent vertical waggle dance and a single comb. The common ancestor of the giant and cavity-dwelling bees is strongly inferred to have had a buzzing vertical directional dance. All pairwise combinations of characters showed strong association, but the multiple comparisons problem reduces the ability to infer associations between states between characters. Nevertheless, a buzzing dance is significantly associated with cavity-nesting, several vertical combs, and dancing vertically, a horizontal dance is significantly associated with a nest with a single comb wrapped around the support, and open nesting with a single pendant comb and a silent waggle dance.

  2. Bees do not use nearest-neighbour rules for optimization of multi-location routes.

    PubMed

    Lihoreau, Mathieu; Chittka, Lars; Le Comber, Steven C; Raine, Nigel E

    2012-02-23

    Animals collecting patchily distributed resources are faced with complex multi-location routing problems. Rather than comparing all possible routes, they often find reasonably short solutions by simply moving to the nearest unvisited resources when foraging. Here, we report the travel optimization performance of bumble-bees (Bombus terrestris) foraging in a flight cage containing six artificial flowers arranged such that movements between nearest-neighbour locations would lead to a long suboptimal route. After extensive training (80 foraging bouts and at least 640 flower visits), bees reduced their flight distances and prioritized shortest possible routes, while almost never following nearest-neighbour solutions. We discuss possible strategies used during the establishment of stable multi-location routes (or traplines), and how these could allow bees and other animals to solve complex routing problems through experience, without necessarily requiring a sophisticated cognitive representation of space.

  3. Comparison and examination of Bombus occidentalis and Bombus impatiens (Hymenoptera: Apidae) in tomato greenhouses.

    PubMed

    Whittington, Robin; Winston, Mark L

    2004-08-01

    Experiments were conducted in commercial tomato, Lycopersicon esculentum Miller (Solanaceae), greenhouses to compare the relative foraging effort of two bumble bee species, Bombus occidentalis Greene and Bombus impatiens Cresson, to examine interspecific competition between B. occidentalis and B. impatiens, and to determine whether bumble bee colonies grew to their full population potential in commercial tomato greenhouses. B. impatiens colonies had more brood and workers and made more foraging trips per hour than B. occidentalis colonies. However, B. impatiens returned to the colony without pollen loads and left their colonies without dropping off their pollen loads more frequently than B. occidentalis greenhouse colonies. Our data also suggest that the presence of B. impatiens had a detrimental effect on B. occidentalis populations. Furthermore, B. occidentalis colonies did not grow to their full population potential in tomato greenhouses, with fewer workers in greenhouse colonies than in colonies placed outside in a natural environment, or in colonies that were physically enclosed and protected from external mortality. Together, this study suggests that B. impatiens is a better pollinator than B. occidentalis. It also shows that unknown factors are limiting the size of B. occidentalis colonies in tomato greenhouses.

  4. Bumble bees of the western United States

    USDA-ARS?s Scientific Manuscript database

    Bumble bees (genus Bombus) are critical pollinators of flowering plants. Thirty species of bumble bees are native to the western United States and this publication is a guide to the natural history and identification of these species. We present phenology graphs, host-plant associations, detailed ...

  5. Comparative analysis of detection limits and specificity of molecular diagnostic markers for three pathogens (Microsporidia, Nosema spp.) in the key pollinators Apis mellifera and Bombus terrestris.

    PubMed

    Erler, Silvio; Lommatzsch, Stefanie; Lattorff, H Michael G

    2012-04-01

    Global pollinator decline has recently been discussed in the context of honey and bumble bee infections from various pathogens including viruses, bacteria, microsporidia and mites. The microsporidian pathogens Nosema apis, Nosema ceranae and Nosema bombi may in fact be major candidates contributing to this decline. Different molecular and non-molecular detection methods have been developed; however, a comparison, especially of the highly sensitive PCR based methods, is currently lacking. Here, we present the first comparative quantitative real-time PCR study of nine Nosema spp. primers within the framework of primer specificity and sensitivity. With the help of dilution series of defined numbers of spores, we reveal six primer pairs amplifying N. apis, six for N. bombi and four for N. ceranae. All appropriate primer pairs detected an amount of at least 10(4) spores, the majority of which were even as sensitive to detect such low amounts as 10(3) to ten spores. Species specificity of primers was observed for N. apis and N. bombi, but not for N. ceranae. Additionally, we did not find any significant correlation for the amplified fragments with PCR efficiency or the limit of detection. We discuss our findings on the background of false positive and negative results using quantitative real-time PCR. On the basis of these results, future research might be based on appropriate primer selection depending on the experimental needs. Primers may be selected on the basis of specificity or sensitivity. Pathogen species and load may be determined with higher precision enhancing all kinds of diagnostic studies.

  6. To be on the safe site - Ungroomed spots on the bee's body and their importance for pollination.

    PubMed

    Koch, Laura; Lunau, Klaus; Wester, Petra

    2017-01-01

    Flower-visiting bees collect large quantities of pollen to feed their offspring. Pollen deposited in the bees' transport organs is lost for the flowers' pollination. It has been hypothesised that specific body areas, bees cannot groom, serve as 'safe sites' for pollen transfer between flowers. For the first time, we experimentally demonstrated the position, area and pollen amount of safe sites at the examples of Apis mellifera and Bombus terrestris by combining artificial contamination of the bees' body with pine or sunflower pollen and the subsequent bees' incomplete grooming. We found safe sites on the forehead, the dorsal thorax and waist, and on the dorsal and ventral abdomen of the bees. These areas were less groomed by the bees' legs. The largest amount of pollen was found on the waist, followed by the dorsal areas of thorax and abdomen. At the example of Salvia pratensis, S. officinalis and Borago officinalis, we experimentally demonstrated with fluorescent dye that the flowers' pollen-sacs and stigma contact identical safe sites. These results confirm that pollen deposition on the bees' safe sites improves pollen transfer to stigmas of conspecific flowers sti. Future research will demonstrate the importance of safe sites for plant pollination under field conditions.

  7. Molecular detection of Spiroplasma apis and Spiroplasma melliferum in bees.

    PubMed

    Meeus, Ivan; Vercruysse, Vicky; Smagghe, Guy

    2012-01-01

    Spiroplasma apis and Spiroplasma melliferum are known as honey bee pathogens and are detected by unspecific methodologies like culturing or dark field microscopy. We developed a multiplex PCR being able to differentiate between both species and detect the genus Spiroplasma. This PCR can directly be used on culture samples or on DNA extracted bees. By PCR on cultured samples we were able to identify S. apis in Bombus pratorum and S. melliferum in Bombus pascuorum.

  8. Local bumble bee decline linked to recovery of honey bees, drought effects on floral resources.

    PubMed

    Thomson, Diane M

    2016-10-01

    Time series of abundances are critical for understanding how abiotic factors and species interactions affect population dynamics, but are rarely linked with experiments and also scarce for bee pollinators. This gap is important given concerns about declines in some bee species. I monitored honey bee (Apis mellifera) and bumble bee (Bombus spp.) foragers in coastal California from 1999, when feral A. mellifera populations were low due to Varroa destructor, until 2014. Apis mellifera increased substantially, except between 2006 and 2011, coinciding with declines in managed populations. Increases in A. mellifera strongly correlated with declines in Bombus and reduced diet overlap between them, suggesting resource competition consistent with past experimental results. Lower Bombus numbers also correlated with diminished floral resources. Declines in floral abundances were associated with drought and reduced spring rainfall. These results illustrate how competition with an introduced species may interact with climate to drive local decline of native pollinators. © 2016 John Wiley & Sons Ltd/CNRS.

  9. Synergistic mortality between a neonicotinoid insecticide and an ergosterol-biosynthesis-inhibiting fungicide in three bee species.

    PubMed

    Sgolastra, Fabio; Medrzycki, Piotr; Bortolotti, Laura; Renzi, Maria Teresa; Tosi, Simone; Bogo, Gherardo; Teper, Dariusz; Porrini, Claudio; Molowny-Horas, Roberto; Bosch, Jordi

    2017-06-01

    Neonicotinoid insecticides have been identified as an important factor contributing to bee diversity declines. Nonetheless, uncertainties remain about their impact under field conditions. Most studies have been conducted on Apis mellifera and tested single compounds. However, in agricultural environments, bees are often exposed to multiple pesticides. We explore the synergistic mortality between a neonicotinoid (clothianidin) and an ergosterol-biosynthesis-inhibiting fungicide (propiconazole) in three bee species (A. mellifera, Bombus terrestris, Osmia bicornis) following oral exposure in the laboratory. We developed a new approach based on the binomial proportion test to analyse synergistic interactions. We estimated uptake of clothianidin per foraging bout in honey bees foraging on seed-coated rapeseed fields. We found significant synergistic mortality in all three bee species exposed to non-lethal doses of propiconazole and their respective LD10 of clothianidin. Significant synergism was only found at the first assessment times in A. mellifera (4 and 24 h) and B. terrestris (4 h), but persisted throughout the experiment (96 h) in O. bicornis. O. bicornis was also the most sensitive species to clothianidin. Our results underscore the importance to test pesticide combinations likely to occur in agricultural environments, and to include several bee species in environmental risk assessment schemes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze.

    PubMed

    Samuelson, Elizabeth E W; Chen-Wishart, Zachary P; Gill, Richard J; Leadbeater, Ellouise

    2016-12-13

    Pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. Inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. One cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. To test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee Bombus terrestris, using an adaptation of the radial-arm maze (RAM). We first demonstrated that bumblebees use spatial working memory to solve the RAM by showing that untreated bees performed significantly better than would be expected if choices were random or governed by stereotyped visitation rules. We then exposed bees to either a high sub-lethal positive control thiamethoxam dose (2.5 ng(-1) bee), or one of two low doses (0.377 or 0.091 ng(-1)) based on estimated field-realistic exposure. The high dose caused bees to make more and earlier spatial memory errors and take longer to complete the task than unexposed bees. For the low doses, the negative effects were smaller but statistically significant, and dependent on bee size. The spatial working memory impairment shown here has the potential to harm bees exposed to thiamethoxam, through possible impacts on foraging efficiency or homing.

  11. Effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze

    NASA Astrophysics Data System (ADS)

    Samuelson, Elizabeth E. W.; Chen-Wishart, Zachary P.; Gill, Richard J.; Leadbeater, Ellouise

    2016-12-01

    Pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. Inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. One cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. To test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee Bombus terrestris, using an adaptation of the radial-arm maze (RAM). We first demonstrated that bumblebees use spatial working memory to solve the RAM by showing that untreated bees performed significantly better than would be expected if choices were random or governed by stereotyped visitation rules. We then exposed bees to either a high sub-lethal positive control thiamethoxam dose (2.5 ng-1 bee), or one of two low doses (0.377 or 0.091 ng-1) based on estimated field-realistic exposure. The high dose caused bees to make more and earlier spatial memory errors and take longer to complete the task than unexposed bees. For the low doses, the negative effects were smaller but statistically significant, and dependent on bee size. The spatial working memory impairment shown here has the potential to harm bees exposed to thiamethoxam, through possible impacts on foraging efficiency or homing.

  12. Effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze

    PubMed Central

    Samuelson, Elizabeth E. W.; Chen-Wishart, Zachary P.; Gill, Richard J.; Leadbeater, Ellouise

    2016-01-01

    Pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. Inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. One cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. To test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee Bombus terrestris, using an adaptation of the radial-arm maze (RAM). We first demonstrated that bumblebees use spatial working memory to solve the RAM by showing that untreated bees performed significantly better than would be expected if choices were random or governed by stereotyped visitation rules. We then exposed bees to either a high sub-lethal positive control thiamethoxam dose (2.5 ng−1 bee), or one of two low doses (0.377 or 0.091 ng−1) based on estimated field-realistic exposure. The high dose caused bees to make more and earlier spatial memory errors and take longer to complete the task than unexposed bees. For the low doses, the negative effects were smaller but statistically significant, and dependent on bee size. The spatial working memory impairment shown here has the potential to harm bees exposed to thiamethoxam, through possible impacts on foraging efficiency or homing. PMID:27958350

  13. Bumble-bees learn the value of social cues through experience

    PubMed Central

    Leadbeater, Ellouise; Chittka, Lars

    2009-01-01

    Natural selection should lead animals to use social cues (SC) when they are useful, and disregard them when they are not. Theoretical investigation predicts that individuals should thus employ social learning ‘strategies’, but how might such context specificity be achieved on a proximate level? Operant conditioning, whereby the use of SC is reinforced through rewarding results, provides a potential mechanism. We investigate the role of reinforcement in joining behaviour in bumble-bees, Bombus terrestris. When bees visit unfamiliar flower species, they prefer to probe inflorescences where others are also foraging, and here we show that such behaviour is promoted through experience when conspecific presence reliably predicts reward. Our findings highlight a straightforward, but rarely discussed, mechanism by which animals can be selective about when to use SC. PMID:19324653

  14. Diversity and phylotype consistency of bacteria in the guts of three bee species (Apoidea) at an oilseed rape field.

    PubMed

    Mohr, Kathrin I; Tebbe, Christoph C

    2006-02-01

    The gut of insects may harbour one of the largest reservoirs of a yet unexplored microbial diversity. To understand how specific insects select for their own bacterial communities, the structural diversity and variability of bacteria found in the gut of different bee species was analysed. For three successive years, adults and larvae of Apis mellifera ssp. carnica (honey bee), and Bombus terrestris (bumble bee), as well as larvae of Osmia bicornis (red mason bee) were collected at a flowering oilseed rape field. Total DNA was extracted from gut material and the bacterial diversity was analysed, independent of cultivation, by genetic profiling with single-strand conformation polymorphism (SSCP) of polymerase chain reaction (PCR)-amplified partial 16S rRNA genes. The SSCP profiles were specific for all bee species and for larvae and adults. Qualitative and quantitative differences were found in the bacterial community structure of larvae and adults of A. mellifera, but differences in B. terrestris were mainly quantitative. Sequencing of the PCR products revealed a dominance of Alpha-, Beta-, and Gammaproteobacteria, Bacteroidetes, and Firmicutes in all bee species. Single-strand conformation polymorphism profiles suggested a higher abundance and diversity of lactobacilli in adults of A. mellifera than in larvae. Further phylogenetic analyses indicated common bacterial phylotypes for all three bee species, e.g. those related to Simonsiella, Serratia, and Lactobacillus. Clades related to Delftia acidovorans, Pseudomonas aeruginosa or Lactobacillus intestinalis only contained sequences from larvae. Several of the bee-specific clusters also contained identical or highly similar sequences from bacteria detected in other A. mellifera subspecies from South Africa, suggesting the existence of cosmopolitan gut bacteria in bees.

  15. Comparative toxicity of pesticides and environmental contaminants in bees: Are honey bees a useful proxy for wild bee species?

    PubMed

    Heard, Matthew S; Baas, Jan; Dorne, Jean-Lou; Lahive, Elma; Robinson, Alexander G; Rortais, Agnes; Spurgeon, David J; Svendsen, Claus; Hesketh, Helen

    2017-02-01

    Threats to wild and managed insect pollinators in Europe are cause for both ecological and socio-economic concern. Multiple anthropogenic pressures may be exacerbating pollinator declines. One key pressure is exposure to chemicals including pesticides and other contaminants. Historically the honey bee (Apis mellifera spp.) has been used as an 'indicator' species for 'standard' ecotoxicological testing but it has been suggested that it is not always a good proxy for other types of eusocial and solitary bees because of species differences in autecology and sensitivity to various stressors. We developed a common toxicity test system to conduct acute and chronic exposures of up to 240h of similar doses of seven chemicals, targeting different metabolic pathways, on three bee species (Apis mellifera spp., Bombus terrestris and Osmia bicornis). We compared the relative sensitivity between species in terms of potency between the chemicals and the influence of exposure time on toxicity. While there were significant interspecific differences that varied through time, overall the magnitude of these differences (in terms of treatment effect ratios) was generally comparable (<2 fold) although there were some large divergences from this pattern. Our results suggest that A. mellifera spp. could be used as a proxy for other bee species provided a reasonable assessment factor is used to cover interspecific variation. Perhaps more importantly our results show significant and large time dependency of toxicity across all three tested species that greatly exceeds species differences (>25 fold within test). These are rarely considered in standard regulatory testing but may have severe environmental consequences, especially when coupled with the likelihood of differential species exposures in the wild. These insights indicate that further work is required to understand how differences in toxicokinetics vary between species and mixtures of chemicals.

  16. Interspecific geographic distribution and variation of the pathogens Nosema bombi and Crithidia species in United States bumble bee populations.

    PubMed

    Cordes, Nils; Huang, Wei-Fone; Strange, James P; Cameron, Sydney A; Griswold, Terry L; Lozier, Jeffrey D; Solter, Leellen F

    2012-02-01

    Several bumble bee (Bombus) species in North America have undergone range reductions and rapid declines in relative abundance. Pathogens have been suggested as causal factors, however, baseline data on pathogen distributions in a large number of bumble bee species have not been available to test this hypothesis. In a nationwide survey of the US, nearly 10,000 specimens of 36 bumble bee species collected at 284 sites were evaluated for the presence and prevalence of two known Bombus pathogens, the microsporidium Nosema bombi and trypanosomes in the genus Crithidia. Prevalence of Crithidia was ≤10% for all host species examined but was recorded from 21% of surveyed sites. Crithidia was isolated from 15 of the 36 Bombus species screened, and were most commonly recovered from Bombus bifarius, Bombus bimaculatus, Bombus impatiens and Bombus mixtus. Nosema bombi was isolated from 22 of the 36 US Bombus species collected. Only one species with more than 50 sampled bees, Bombus appositus, was free of the pathogen; whereas, prevalence was highest in Bombus occidentalis and Bombus pensylvanicus, two species that are reportedly undergoing population declines in North America. A variant of a tetranucleotide repeat in the internal transcribed spacer (ITS) of the N. bombi rRNA gene, thus far not reported from European isolates, was isolated from ten US Bombus hosts, appearing in varying ratios in different host species. Given the genetic similarity of the rRNA gene of N. bombi sampled in Europe and North America to date, the presence of a unique isolate in US bumble could reveal one or more native North American strains and indicate that N. bombi is enzootic across the Holarctic Region, exhibiting some genetic isolation.

  17. Whole-Genome Sequence Analysis of Bombella intestini LMG 28161T, a Novel Acetic Acid Bacterium Isolated from the Crop of a Red-Tailed Bumble Bee, Bombus lapidarius

    PubMed Central

    Li, Leilei; Illeghems, Koen; Van Kerrebroeck, Simon; Borremans, Wim; Cleenwerck, Ilse; Smagghe, Guy; De Vuyst, Luc

    2016-01-01

    The whole-genome sequence of Bombella intestini LMG 28161T, an endosymbiotic acetic acid bacterium (AAB) occurring in bumble bees, was determined to investigate the molecular mechanisms underlying its metabolic capabilities. The draft genome sequence of B. intestini LMG 28161T was 2.02 Mb. Metabolic carbohydrate pathways were in agreement with the metabolite analyses of fermentation experiments and revealed its oxidative capacity towards sucrose, D-glucose, D-fructose and D-mannitol, but not ethanol and glycerol. The results of the fermentation experiments also demonstrated that the lack of effective aeration in small-scale carbohydrate consumption experiments may be responsible for the lack of reproducibility of such results in taxonomic studies of AAB. Finally, compared to the genome sequences of its nearest phylogenetic neighbor and of three other insect associated AAB strains, the B. intestini LMG 28161T genome lost 69 orthologs and included 89 unique genes. Although many of the latter were hypothetical they also included several type IV secretion system proteins, amino acid transporter/permeases and membrane proteins which might play a role in the interaction with the bumble bee host. PMID:27851750

  18. Geographic profiling applied to testing models of bumble-bee foraging

    PubMed Central

    Raine, Nigel E.; Rossmo, D. Kim; Le Comber, Steven C.

    2008-01-01

    Geographic profiling (GP) was originally developed as a statistical tool to help police forces prioritize lists of suspects in investigations of serial crimes. GP uses the location of related crime sites to make inferences about where the offender is most likely to live, and has been extremely successful in criminology. Here, we show how GP is applicable to experimental studies of animal foraging, using the bumble-bee Bombus terrestris. GP techniques enable us to simplify complex patterns of spatial data down to a small number of parameters (2–3) for rigorous hypothesis testing. Combining computer model simulations and experimental observation of foraging bumble-bees, we demonstrate that GP can be used to discriminate between foraging patterns resulting from (i) different hypothetical foraging algorithms and (ii) different food item (flower) densities. We also demonstrate that combining experimental and simulated data can be used to elucidate animal foraging strategies: specifically that the foraging patterns of real bumble-bees can be reliably discriminated from three out of nine hypothetical foraging algorithms. We suggest that experimental systems, like foraging bees, could be used to test and refine GP model predictions, and that GP offers a useful technique to analyse spatial animal behaviour data in both the laboratory and field. PMID:18664426

  19. Sex ratios in bumble bees

    PubMed Central

    Bourke, A. F. G.

    1997-01-01

    The median proportion of investment in females among 11 populations of seven bumble bee (Bombus) species was 0.32 (range 0.07 to 0.64). By contrast, two species of workerless social parasites in the related genus Psithyrus had female-biased sex allocation, the reasons for which remain unclear. Male-biased sex allocation in Bombus contradicts the predictions of Trivers and Hare's sex ratio model for the social Hymenoptera, which are that the population sex investment ratio should be 0.5 (1:1) under queen control and 0.75 (3:1 females:males) under worker control (assuming single, once-mated, outbred queens and non-reproductive workers). Male bias in Bombus does not appear to be either an artefact, or purely the result of symbiotic sex ratio distorters. According to modifications of the Trivers–Hare model, the level of worker male-production in Bombus is insufficient to account for observed levels of male bias. There is also no evidence that male bias arises from either local resource competition (related females compete for resources) or local mate enhancement (related males cooperate in securing mates). Bulmer presented models predicting sexual selection for protandry (males are produced before females) in annual social Hymenoptera and, as a consequence (given some parameter values), male-biased sex allocation. Bumble bees fit the assumptions of Bulmer's models and are protandrous. These models therefore represent the best current explanation for the bees' male-biased sex investment ratios. This conclusion suggests that the relative timing of the production of the sexes strongly influences sex allocation in the social Hymenoptera.

  20. Refugia, biodiversity, and pollination roles of bumble bees in the Madrean Archipelago

    Treesearch

    Justin O. Schmidt; Robert S. Jacobson

    2005-01-01

    Eight species of bumble bees (Hymenoptera: Apidae: Bombus) are present within five major Sky Island mountains of southern Arizona. Another four species exist in the nearby large mountainous region stretching from the Arizona White Mountains to Flagstaff. The distribution and number of bumble bee species within the individual Sky Island mountains varies from six in the...

  1. Flight performance of bumble bee as a possible pollinator in space agriculture under partial gravity

    NASA Astrophysics Data System (ADS)

    Yamashita, Masamichi; Hashimoto, Hirofumi; Mitsuhata, Masahiro; Sasaki, Masami; Space Agriculture Task Force, J.

    Space agriculture is an advanced life support concept for habitation on extraterrestrial bodies based on biological and ecological function. Flowering plant species are core member of space agriculture to produce food and revitalize air and water. Selection of crop plant species is made on the basis of nutritional requirements to maintain healthy life of space crew. Species selected for space agriculture have several mode of reproduction. For some of plant species, insect pollination is effective to increase yield and quality of food. In terrestrial agriculture, bee is widely introduced to pollinate flower. For pollinator insect on Mars, working environment is different from Earth. Magnitude of gravity is 0.38G on Mars surface. In order to confirm feasibility of insect pollination for space agriculture, capability of flying pollinator insect under such exotic condition should be examined. Even bee does not possess evident gravity sensory system, gravity dominates flying performance and behavior. During flight or hovering, lifting force produced by wing beat sustains body weight, which is the product of body mass and gravitational acceleration. Flying behavior of bumble bee, Bombus ignitus, was documented under partial or micro-gravity produced by parabolic flight of jet plane. Flying behavior at absence of gravity differed from that under normal gravity. Ability of bee to fly under partial gravity was examined at the level of Mars, Moon and the less, to determine the threshold level of gravity for bee flying maneuver. Adaptation process of bee flying under different gravity level was evaluated as well by successive documentation of parabolic flight experiment.

  2. Replication of honey bee-associated RNA viruses across multiple bee species in apple orchards of Georgia, Germany and Kyrgyzstan.

    PubMed

    Radzevičiūtė, Rita; Theodorou, Panagiotis; Husemann, Martin; Japoshvili, George; Kirkitadze, Giorgi; Zhusupbaeva, Aigul; Paxton, Robert J

    2017-06-01

    The essential ecosystem service of pollination is provided largely by insects, which are considered threatened by diverse biotic and abiotic global change pressures. RNA viruses are one such pressure, and have risen in prominence as a major threat for honey bees (Apis mellifera) and global apiculture, as well as a risk factor for other bee species through pathogen spill-over between managed honey bees and sympatric wild pollinator communities. Yet despite their potential role in global bee decline, the prevalence of honey bee-associated RNA viruses in wild bees is poorly known from both geographic and taxonomic perspectives. We screened members of pollinator communities (honey bees, bumble bees and other wild bees belonging to four families) collected from apple orchards in Georgia, Germany and Kyrgyzstan for six common honey bee-associated RNA virus complexes encompassing nine virus targets. The Deformed wing virus complex (DWV genotypes A and B) had the highest prevalence across all localities and host species and was the only virus complex found in wild bee species belonging to all four studied families. Based on amplification of negative-strand viral RNA, we found evidence for viral replication in wild bee species of DWV-A/DWV-B (hosts: Andrena haemorrhoa and several Bombus spp.) and Black queen cell virus (hosts: Anthophora plumipes, several Bombus spp., Osmia bicornis and Xylocopa spp.). Viral amplicon sequences revealed that DWV-A and DWV-B are regionally distinct but identical in two or more bee species at any one site, suggesting virus is shared amongst sympatric bee taxa. This study demonstrates that honey bee associated RNA viruses are geographically and taxonomically widespread, likely infective in wild bee species, and shared across bee taxa. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The conservation and restoration of wild bees.

    PubMed

    Winfree, Rachael

    2010-05-01

    Bees pollinate most of the world's wild plant species and provide economically valuable pollination services to crops; yet knowledge of bee conservation biology lags far behind other taxa such as vertebrates and plants. There are few long-term data on bee populations, which makes their conservation status difficult to assess. The best-studied groups are the genus Bombus (the bumble bees), and bees in the EU generally; both of these are clearly declining. However, it is not known to what extent these groups represent the approximately 20,000 species of bees globally. As is the case for insects in general, bees are underrepresented in conservation planning and protection efforts. For example, only two bee species are on the global IUCN Red List, and no bee is listed under the U.S. Endangered Species Act, even though many bee species are known to be in steep decline or possibly extinct. At present, bee restoration occurs mainly in agricultural contexts, funded by government programs such as agri-environment schemes (EU) and the Farm Bill (USA). This is a promising approach given that many bee species can use human-disturbed habitats, and bees provide valuable pollination services to crops. However, agricultural restorations only benefit species that persist in agricultural landscapes, and they are more expensive than preserving natural habitat elsewhere. Furthermore, such restorations benefit bees in only about half of studied cases. More research is greatly needed in many areas of bee conservation, including basic population biology, bee restoration in nonagricultural contexts, and the identification of disturbance-sensitive bee species.

  4. Monitoring Flower Visitation Networks and Interactions between Pairs of Bumble Bees in a Large Outdoor Flight Cage

    PubMed Central

    Lihoreau, Mathieu; Chittka, Lars; Raine, Nigel E.

    2016-01-01

    Pollinators, such as bees, often develop multi-location routes (traplines) to exploit subsets of flower patches within larger plant populations. How individuals establish such foraging areas in the presence of other foragers is poorly explored. Here we investigated the foraging patterns of pairs of bumble bees (Bombus terrestris) released sequentially into an 880m2 outdoor flight cage containing 10 feeding stations (artificial flowers). Using motion-sensitive video cameras mounted on flowers, we mapped the flower visitation networks of both foragers, quantified their interactions and compared their foraging success over an entire day. Overall, bees that were released first (residents) travelled 37% faster and collected 77% more nectar, thereby reaching a net energy intake rate 64% higher than bees released second (newcomers). However, this prior-experience advantage decreased as newcomers became familiar with the spatial configuration of the flower array. When both bees visited the same flower simultaneously, the most frequent outcome was for the resident to evict the newcomer. On the rare occasions when newcomers evicted residents, the two bees increased their frequency of return visits to that flower. These competitive interactions led to a significant (if only partial) spatial overlap between the foraging patterns of pairs of bees. While newcomers may initially use social cues (such as olfactory footprints) to exploit flowers used by residents, either because such cues indicate higher rewards and/or safety from predation, residents may attempt to preserve their monopoly over familiar resources through exploitation and interference. We discuss how these interactions may favour spatial partitioning, thereby maximising the foraging efficiency of individuals and colonies. PMID:26982030

  5. Monitoring Flower Visitation Networks and Interactions between Pairs of Bumble Bees in a Large Outdoor Flight Cage.

    PubMed

    Lihoreau, Mathieu; Chittka, Lars; Raine, Nigel E

    2016-01-01

    Pollinators, such as bees, often develop multi-location routes (traplines) to exploit subsets of flower patches within larger plant populations. How individuals establish such foraging areas in the presence of other foragers is poorly explored. Here we investigated the foraging patterns of pairs of bumble bees (Bombus terrestris) released sequentially into an 880m2 outdoor flight cage containing 10 feeding stations (artificial flowers). Using motion-sensitive video cameras mounted on flowers, we mapped the flower visitation networks of both foragers, quantified their interactions and compared their foraging success over an entire day. Overall, bees that were released first (residents) travelled 37% faster and collected 77% more nectar, thereby reaching a net energy intake rate 64% higher than bees released second (newcomers). However, this prior-experience advantage decreased as newcomers became familiar with the spatial configuration of the flower array. When both bees visited the same flower simultaneously, the most frequent outcome was for the resident to evict the newcomer. On the rare occasions when newcomers evicted residents, the two bees increased their frequency of return visits to that flower. These competitive interactions led to a significant (if only partial) spatial overlap between the foraging patterns of pairs of bees. While newcomers may initially use social cues (such as olfactory footprints) to exploit flowers used by residents, either because such cues indicate higher rewards and/or safety from predation, residents may attempt to preserve their monopoly over familiar resources through exploitation and interference. We discuss how these interactions may favour spatial partitioning, thereby maximising the foraging efficiency of individuals and colonies.

  6. Review of field and monitoring studies investigating the role of nitro-substituted neonicotinoid insecticides in the reported losses of honey bee colonies (Apis mellifera).

    PubMed

    Schmuck, Richard; Lewis, Gavin

    2016-11-01

    The nitro-substituted neonicotinoid insecticides, which include imidacloprid, thiamethoxam and clothianidin, are widely used to control a range of important agricultural pests both by foliar applications and also as seed dressings and by soil application. Since they exhibit systemic properties, exposure of bees may occur as a result of residues present in the nectar and/or pollen of seed- or soil-treated crop plants and so they have been the subject of much debate about whether they cause adverse effects in pollinating insects under field conditions. Due to these perceived concerns, the use of the three neonicotinoids imidacloprid, clothianidin and thiamethoxam has been temporarily suspended in the European Union for seed treatment, soil application and foliar treatment in crops attractive to bees. Monitoring data from a number of countries are available to assess the presence of neonicotinoid residues in honey bee samples and possible impacts at the colony level and these are reviewed here together with a number of field studies which have looked at the impact of clothiandin on honey bees in relation to specific crop use and in particular with oilseed rape. Currently there is considerable uncertainty with regards to the regulatory testing requirements for field studies. Accordingly, a testing protocol was developed to address any acute and chronic risks from oilseed rape seeds containing a coating with 10 g clothianidin and 2 g beta-cyfluthrin per kg seeds (Elado(®)) for managed honey bee (Apis mellifera) colonies, commercially bred bumble bee (Bombus terrestris) colonies and red mason bees (Osmia bicornis) as a representative solitary bee species. This is described here together with a summary of the results obtained as an introduction to the study details given in the following papers in this issue.

  7. Conspecifics as informers and competitors: an experimental study in foraging bumble-bees

    PubMed Central

    Baude, Mathilde; Danchin, Étienne; Mugabo, Marianne; Dajoz, Isabelle

    2011-01-01

    Conspecifics are usually considered competitors negatively affecting food intake rates. However, their presence can also inform about resource quality by providing inadvertent social information. Few studies have investigated whether foragers perceive conspecifics as informers or competitors. Here, we experimentally tested whether variation in the density of demonstrators (‘none’, ‘low’ and ‘high’), whose location indicated flower profitability, affected decision-making of bumble-bees Bombus terrestris. Bumble-bees foraged on either ‘simple’ (two colours) or ‘complex’ (four colours) artificial floral communities. We found that conspecifics at low density may be used as sources of information in first flower choices, whereas they appeared as competitors over the whole foraging sequence. Low conspecific densities improved foragers' first-visit success rate in the simple environment, and decreased time to first landing, especially in the complex environment. High conspecific densities did not affect these behavioural parameters, but reduced flower constancy in both floral communities, which may alter the efficiency of pollinating visits. These results suggest that the balance of the costs and benefits of conspecific presence varies with foraging experience, floral community and density. Spatio-temporal scales could thus be an important determinant of social information use. This behavioural flexibility should allow bumble-bees to better exploit their environment. PMID:21288951

  8. Incidents of bee poisoning with pesticides in the United Kingdom, 1994-2003.

    PubMed

    Barnett, Elizabeth A; Charlton, Andrew J; Fletcher, Mark R

    2007-11-01

    For over 20 years, the UK Agriculture Departments have monitored the direct effects of pesticides on beneficial insects, mainly honeybees (Apis mellifera, L.) and bumblebees (Bombus terrestris, L.), as part of the Wildlife Incident Investigation Scheme (WIIS). The Central Science Laboratory (CSL) has contributed to WIIS by providing the required laboratory skills for the determination of bee diseases and the expert analytical experience necessary to determine low-level pesticide residues and interpret these results. The results from WIIS form part of the pesticide regulatory process coordinated by the Pesticides Safety Directorate (PSD) and are published each year. This paper has reviewed the data from WIIS over the 10 year period from 1994 to 2003. The overall trend is that suspected poisoning incidents, reported by beekeepers and the general public, have declined from 56 incidents per year to 23 incidents per year. The number of these incidents that have been attributed to pesticide poisoning has also declined, from 25 incidents to five incidents per year. The possible reasons for these changes and the circumstances involved in the bee poisoning incidents are discussed. However, the source of the pesticide in bee poisoning incidents is often uncertain and the likely cause of these incidents and any trends over time are also discussed.

  9. Fast learning in free-foraging bumble bees is negatively correlated with lifetime resource collection.

    PubMed

    Evans, Lisa J; Smith, Karen E; Raine, Nigel E

    2017-03-29

    Despite widespread interest in the potential adaptive value of individual differences in cognition, few studies have attempted to address the question of how variation in learning and memory impacts their performance in natural environments. Using a novel split-colony experimental design we evaluated visual learning performance of foraging naïve bumble bees (Bombus terrestris) in an ecologically relevant associative learning task under controlled laboratory conditions, before monitoring the lifetime foraging performance of the same individual bees in the field. We found appreciable variation among the 85 workers tested in both their learning and foraging performance, which was not predicted by colony membership. However, rather than finding that foragers benefited from enhanced learning performance, we found that fast and slow learners collected food at comparable rates and completed a similar number of foraging bouts per day in the field. Furthermore, bees with better learning abilities foraged for fewer days; suggesting a cost of enhanced learning performance in the wild. As a result, slower learning individuals collected more resources for their colony over the course of their foraging career. These results demonstrate that enhanced cognitive traits are not necessarily beneficial to the foraging performance of individuals or colonies in all environments.

  10. Cloning and expression profiling of four antibacterial peptide genes from the bumblebee Bombus ignitus.

    PubMed

    Choi, Yong Soo; Choo, Young Moo; Lee, Kwang Sik; Yoon, Hyung Joo; Kim, Iksoo; Je, Yeon Ho; Sohn, Hung Dae; Jin, Byung Rae

    2008-06-01

    Four antibacterial peptide genes (apidaecin, hymenoptaecin, abaecin, and defensin) were cloned from the bumblebee Bombus ignitus, and cDNAs and their genomic structures were sequenced and characterized. Comparative analysis revealed that the four antibacterial peptides of B. ignitus had similar characteristics to other bee antibacterial peptides identified to date. The transcriptional expression profiles of the four antibacterial peptide genes in the fat body of B. ignitus workers revealed that all four antibacterial peptide genes were acutely induced in a similar manner by PBS injection or LPS stimulation, indicating that antibacterial peptides from various classes are simultaneously expressed in a single insect upon infection or injury.

  11. Conservation and modification of genetic and physiological toolkits underpinning diapause in bumble bee queens.

    PubMed

    Amsalem, Etya; Galbraith, David A; Cnaani, Jonathan; Teal, Peter E A; Grozinger, Christina M

    2015-11-01

    Diapause is the key adaptation allowing insects to survive unfavourable conditions and inhabit an array of environments. Physiological changes during diapause are largely conserved across species and are hypothesized to be regulated by a conserved suite of genes (a 'toolkit'). Furthermore, it is hypothesized that in social insects, this toolkit was co-opted to mediate caste differentiation between long-lived, reproductive, diapause-capable queens and short-lived, sterile workers. Using Bombus terrestris queens, we examined the physiological and transcriptomic changes associated with diapause and CO2 treatment, which causes queens to bypass diapause. We performed comparative analyses with genes previously identified to be associated with diapause in the Dipteran Sarcophaga crassipalpis and with caste differentiation in bumble bees. As in Diptera, diapause in bumble bees is associated with physiological and transcriptional changes related to nutrient storage, stress resistance and core metabolic pathways. There is a significant overlap, both at the level of transcript and gene ontology, between the genetic mechanisms mediating diapause in B. terrestris and S. crassipalpis, reaffirming the existence of a conserved insect diapause genetic toolkit. However, a substantial proportion (10%) of the differentially regulated transcripts in diapausing queens have no clear orthologs in other species, and key players regulating diapause in Diptera (juvenile hormone and vitellogenin) appear to have distinct functions in bumble bees. We also found a substantial overlap between genes related to caste determination and diapause in bumble bees. Thus, our studies demonstrate an intriguing interplay between pathways underpinning adaptation to environmental extremes and the evolution of sociality in insects.

  12. Interspecific geographic distribution and variation of two bumble bee pathogens, Nosema bombi and Crithidia bombi, in United States populations

    USDA-ARS?s Scientific Manuscript database

    Several bumble bee (Bombus) species in North America have undergone range reductions and rapid declines in relative abundance. Pathogens have been suggested as causal factors, however, baseline data on pathogen distributions in a large number of bumble bee species have not been available to rigorous...

  13. The plight of the bees

    USGS Publications Warehouse

    Spivak, Marla; Mader, Eric; Vaughan, Mace; Euliss, Ned H.

    2011-01-01

    Some environmental issues polarize people, producing weary political stalemates of indecision and inaction. Others, however, grab hold of our most primeval instincts, causing us to reach deeply into our memories of childhood, and our first direct experiences with nature: the bumble bee nest we poked at with a stick; the man at the county fair with the bee beard. Those memories expand backward in time to our barefoot ancestors who climbed trees and robbed honey. They help define the human experience and provide context to our own place in the world.And so the plight of the bees strikes a common chord. For a brief moment simple matters of politics, economics, and nationality seem irrelevant. Colony collapse disorder, the name for the syndrome causing honey bees (Apis mellifera) to suddenly and mysteriously disappear from their hives - thousands of individual worker bees literally flying off to die - captured public consciousness when it was first named in 2007 (1). Since then, the story of vanishing honey bees has become ubiquitous in popular consciousness - driving everything from ice cream marketing campaigns to plots for The Simpsons. The untold story is that these hive losses are simply a capstone to more than a half-century of more prosaic day-to-day losses that beekeepers already faced from parasites, diseases, poor nutrition, and pesticide poisoning (2). The larger story still is that while honey bees are charismatic and important to agriculture, other important bees are also suffering, and in some cases their fates are far worse (3). These other bees are a subset of the roughly 4000 species of wild bumble bees (Bombus), leafcutter bees (Megachile), and others that are native to North America. While the honey bee was originally imported from Europe by colonists in the early 17th century, it is these native bees that have evolved with our local ecosystems, and, along with honey bees, are valuable crop pollinators. People want to know why bees are dying and how

  14. Cross-linking in the silks of bees, ants and hornets.

    PubMed

    Campbell, Peter M; Trueman, Holly E; Zhang, Qiang; Kojima, Katsura; Kameda, Tsunenori; Sutherland, Tara D

    2014-05-01

    Silk production is integral to the construction of nests or cocoons for many Aculeata, stinging Hymenopterans such as ants, bees and wasps. Here we report the sequences of new aculeate silk proteins and compare cross-linking among nine native silks from three bee species (Apis mellifera, Bombus terrestris and Megachile rotundata), three ant species (Myrmecia forficata, Oecophylla smaragdina and Harpegnathos saltator) and three hornets (Vespa analis, Vespa simillima and Vespa mandarinia). The well studied silks of spiders and silkworms are comprised of large proteins that are cross-linked and stabilized predominantly by intra and intermolecular beta sheet structure. In contrast, the aculeate silks are comprised of relatively small proteins that contain central coiled coil domains and comparatively reduced amounts of beta sheet structure. The hornet silks, which have the most beta sheet structure and the greatest amount of amino acid sequence outside the coiled-coil domains, dissolve in concentrated LiBr solution and appear to be stabilized predominantly by beta sheet structure like the classic silks. In contrast, the ant and bee silks, which have less beta sheet and less sequence outside the coiled-coil domains, could not be dissolved in LiBr and appear to be predominantly stabilized by covalent cross-linking. The iso-peptide cross-linker, ε-(γ-glutamyl)-lysine that is produced by transglutaminase enzymes, was demonstrated to be present in all silks by mass spectrometry, but at greater levels in silks of ants and bees. The bee silks and ant cocoons, but not the Oecophylla nest silks, appeared to be further stabilized by tanning reactions.

  15. Presence of a thermoregulatory hot spot in the prothorax of the large carpenter bee and the bumble bee.

    PubMed

    Volynchik, Stanislav; Plotkin, Marian; Ermakov, Natalya Y; Bergman, David J; Ishay, Jacob S

    2006-11-01

    In both the large carpenter bee (Xylocopa pubescens) and the bumblebee (Bombus terrestris), a hot spot was detected in the center of the prothorax on its dorsal-external aspect. In both cases, the temperature in this hot spot was found to be greater than the ambient temperature and that at the tip of the gaster. In B. terrestris, it was higher by 9-10 degrees C from that at the gaster tip and by 15-16 degrees C from the ambient temperature, while in X. pubescens the corresponding differences were 11-20 degrees C and 18-19 degrees C, respectively. The recorded thermal differences were not fixed but were rather variable, temporally as well as individually, but invariably all individuals measured showed these temperature differences. Furthermore, in none of the studied specimens was a hot spot detected in any part of the body other than the prothorax. From this hot spot in the prothorax, there is a cascade of temperatures in both directions, that is, anteriorly towards the head and posteriorly towards the gaster, with a graded drop in temperature in either direction. This article discusses possible reasons for the existence of such a hot spot in this particular location (the prothorax), its role or function, and its mode of operation. The authors speculate that it is a thermoregulatory center (for heating or cooling) that might be present in possibly all Hymenoptera that spend a considerable part of their life flying, regardless of whether they are social, parasocial, or solitary.

  16. Effects of habitat composition and landscape structure on worker foraging distances of five bumble bee species.

    PubMed

    Redhead, John W; Dreier, Stephanie; Bourke, Andrew F G; Heard, Matthew S; Jordan, William C; Sumner, Seirian; Wang, Jinliang; Carvell, Claire

    2016-04-01

    Bumble bees (Bombus spp.) are important pollinators of both crops and wildflowers. Their contribution to this essential ecosystem service has been threatened over recent decades by changes in land use, which have led to declines in their populations. In order to design effective conservation measures, it is important to understand the effects of variation in landscape composition and structure on the foraging activities of worker bumble bees. This is because the viability of individual colonies is likely to be affected by the trade-off between the energetic costs of foraging over greater distances and the potential gains from access to additional resources. We used field surveys, molecular genetics, and fine resolution remote sensing to estimate the locations of wild bumble bee nests and to infer foraging distances across a 20-km² agricultural landscape in southern England, UK. We investigated five species, including the rare B. ruderatus and ecologically similar but widespread B. hortorum. We compared worker foraging distances between species and examined how variation in landscape composition and structure affected foraging distances at the colony level. Mean worker foraging distances differed significantly between species. Bombus terrestris, B. lapidarius, and B. ruderatus exhibited significantly greater mean foraging distances (551, 536, and 501 m, respectively) than B. hortorum and B. pascuorum (336 and 272 m, respectively). There was wide variation in worker foraging distances between colonies of the same species, which was in turn strongly influenced by the amount and spatial configuration of available foraging habitats. Shorter foraging distances were found for colonies where the local landscape had high coverage and low fragmentation of semi-natural vegetation, including managed agri-environmental field margins. The strength of relationships between different landscape variables and foraging distance varied between species, for example the strongest

  17. Bumble Bee Fauna of Palouse Prairie: Survey of Native Bee Pollinators in a Fragmented Ecosystem

    PubMed Central

    Hatten, T. D.; Looney, C.; Strange, J. P.; Bosque-Pérez, N. A.

    2013-01-01

    Bumble bees, Bombus Latreille (Hymenoptera: Apidae:), are dominant pollinators in the northern hemisphere, providing important pollination services for commercial crops and innumerable wild plants. Nationwide declines in several bumble bee species and habitat losses in multiple ecosystems have raised concerns about conservation of this important group. In many regions, such as the Palouse Prairie, relatively little is known about bumble bee communities, despite their critical ecosystem functions. Pitfall trap surveys for ground beetles in Palouse prairie remnants conducted in 2002–2003 contained considerable by-catch of bumble bees. The effects of landscape context, remnant features, year, and season on bumble bee community composition were examined. Additionally, bees captured in 2002–2003 were compared with historic records for the region to assess changes in the presence of individual species. Ten species of bumble bee were captured, representing the majority of the species historically known from the region. Few detectable differences in bumble bee abundances were found among remnants. Community composition differed appreciably, however, based on season, landscape context, and elevation, resulting in different bee assemblages between western, low-lying remnants and eastern, higherelevation remnants. The results suggest that conservation of the still species-rich bumble bee fauna should take into account variability among prairie remnants, and further work is required to adequately explain bumble bee habitat associations on the Palouse. PMID:23902138

  18. Does Pathogen Spillover from Commercially Reared Bumble Bees Threaten Wild Pollinators?

    PubMed Central

    Otterstatter, Michael C.; Thomson, James D.

    2008-01-01

    The conservation of insect pollinators is drawing attention because of reported declines in bee species and the ‘ecosystem services’ they provide. This issue has been brought to a head by recent devastating losses of honey bees throughout North America (so called, ‘Colony Collapse Disorder’); yet, we still have little understanding of the cause(s) of bee declines. Wild bumble bees (Bombus spp.) have also suffered serious declines and circumstantial evidence suggests that pathogen ‘spillover’ from commercially reared bumble bees, which are used extensively to pollinate greenhouse crops, is a possible cause. We constructed a spatially explicit model of pathogen spillover in bumble bees and, using laboratory experiments and the literature, estimated parameter values for the spillover of Crithidia bombi, a destructive pathogen commonly found in commercial Bombus. We also monitored wild bumble bee populations near greenhouses for evidence of pathogen spillover, and compared the fit of our model to patterns of C. bombi infection observed in the field. Our model predicts that, during the first three months of spillover, transmission from commercial hives would infect up to 20% of wild bumble bees within 2 km of the greenhouse. However, a travelling wave of disease is predicted to form suddenly, infecting up to 35–100% of wild Bombus, and spread away from the greenhouse at a rate of 2 km/wk. In the field, although we did not observe a large epizootic wave of infection, the prevalences of C. bombi near greenhouses were consistent with our model. Indeed, we found that spillover has allowed C. bombi to invade several wild bumble bee species near greenhouses. Given the available evidence, it is likely that pathogen spillover from commercial bees is contributing to the ongoing decline of wild Bombus in North America. Improved management of domestic bees, for example by reducing their parasite loads and their overlap with wild congeners, could diminish or even

  19. Does pathogen spillover from commercially reared bumble bees threaten wild pollinators?

    PubMed

    Otterstatter, Michael C; Thomson, James D

    2008-07-23

    The conservation of insect pollinators is drawing attention because of reported declines in bee species and the 'ecosystem services' they provide. This issue has been brought to a head by recent devastating losses of honey bees throughout North America (so called, 'Colony Collapse Disorder'); yet, we still have little understanding of the cause(s) of bee declines. Wild bumble bees (Bombus spp.) have also suffered serious declines and circumstantial evidence suggests that pathogen 'spillover' from commercially reared bumble bees, which are used extensively to pollinate greenhouse crops, is a possible cause. We constructed a spatially explicit model of pathogen spillover in bumble bees and, using laboratory experiments and the literature, estimated parameter values for the spillover of Crithidia bombi, a destructive pathogen commonly found in commercial Bombus. We also monitored wild bumble bee populations near greenhouses for evidence of pathogen spillover, and compared the fit of our model to patterns of C. bombi infection observed in the field. Our model predicts that, during the first three months of spillover, transmission from commercial hives would infect up to 20% of wild bumble bees within 2 km of the greenhouse. However, a travelling wave of disease is predicted to form suddenly, infecting up to 35-100% of wild Bombus, and spread away from the greenhouse at a rate of 2 km/wk. In the field, although we did not observe a large epizootic wave of infection, the prevalences of C. bombi near greenhouses were consistent with our model. Indeed, we found that spillover has allowed C. bombi to invade several wild bumble bee species near greenhouses. Given the available evidence, it is likely that pathogen spillover from commercial bees is contributing to the ongoing decline of wild Bombus in North America. Improved management of domestic bees, for example by reducing their parasite loads and their overlap with wild congeners, could diminish or even eliminate pathogen

  20. Exploring the role of juvenile hormone and vitellogenin in reproduction and social behavior in bumble bees

    PubMed Central

    2014-01-01

    Background The genetic and physiological pathways regulating behavior in solitary species are hypothesized to have been co-opted to regulate social behavior in social species. One classic example is the interaction between vitellogenin (an egg-yolk and storage protein) and juvenile hormone, which are positively correlated in most insect species but have modified interactions in highly eusocial insects. In some of these species (including some termites, ants, and the honey bee), juvenile hormone and vitellogenin levels are negatively correlated and juvenile hormone has shifted its role from a gonadotropin to a regulator of maturation and division of labor in the primarily sterile workers. The function of vitellogenin also seems to have broadened to encompass similar roles. Thus, the functions and molecular interactions of juvenile hormone and vitellogenin are hypothesized to have undergone changes during the evolution of eusociality, but the mechanisms underlying these changes are unknown. Bumble bees offer an excellent model system for testing how the relationship between juvenile hormone and vitellogenin evolved from solitary to social species. Bumble bee colonies are primitively eusocial and comprised of a single reproductive queen and facultatively sterile workers. In Bombus terrestris, juvenile hormone retains its ancestral role as a gonadotropin and is also hypothesized to regulate aggressive behavior. However, the function of vitellogenin and its interactions with juvenile hormone have not yet been characterized. Results By characterizing vitellogenin RNA expression levels (vg) in B. terrestris we show that vg is not associated with task and only partially associated with worker age, queen presence, and caste (queen vs worker). The correlations of vg with ovarian activation were not consistent across experiments, but both vg and ovarian activation were significantly associated with levels of aggression experienced by workers. Treatment with juvenile hormone

  1. Exploring the role of juvenile hormone and vitellogenin in reproduction and social behavior in bumble bees.

    PubMed

    Amsalem, Etya; Malka, Osnat; Grozinger, Christina; Hefetz, Abraham

    2014-03-11

    The genetic and physiological pathways regulating behavior in solitary species are hypothesized to have been co-opted to regulate social behavior in social species. One classic example is the interaction between vitellogenin (an egg-yolk and storage protein) and juvenile hormone, which are positively correlated in most insect species but have modified interactions in highly eusocial insects. In some of these species (including some termites, ants, and the honey bee), juvenile hormone and vitellogenin levels are negatively correlated and juvenile hormone has shifted its role from a gonadotropin to a regulator of maturation and division of labor in the primarily sterile workers. The function of vitellogenin also seems to have broadened to encompass similar roles. Thus, the functions and molecular interactions of juvenile hormone and vitellogenin are hypothesized to have undergone changes during the evolution of eusociality, but the mechanisms underlying these changes are unknown.Bumble bees offer an excellent model system for testing how the relationship between juvenile hormone and vitellogenin evolved from solitary to social species. Bumble bee colonies are primitively eusocial and comprised of a single reproductive queen and facultatively sterile workers. In Bombus terrestris, juvenile hormone retains its ancestral role as a gonadotropin and is also hypothesized to regulate aggressive behavior. However, the function of vitellogenin and its interactions with juvenile hormone have not yet been characterized. By characterizing vitellogenin RNA expression levels (vg) in B. terrestris we show that vg is not associated with task and only partially associated with worker age, queen presence, and caste (queen vs worker). The correlations of vg with ovarian activation were not consistent across experiments, but both vg and ovarian activation were significantly associated with levels of aggression experienced by workers. Treatment with juvenile hormone did not affect vg

  2. Genomics and host specialization of honey bee and bumble bee gut symbionts.

    PubMed

    Kwong, Waldan K; Engel, Philipp; Koch, Hauke; Moran, Nancy A

    2014-08-05

    Gilliamella apicola and Snodgrassella alvi are dominant members of the honey bee (Apis spp.) and bumble bee (Bombus spp.) gut microbiota. We generated complete genomes of the type strains G. apicola wkB1(T) and S. alvi wkB2(T) (isolated from Apis), as well as draft genomes for four other strains from Bombus. G. apicola and S. alvi were found to occupy very different metabolic niches: The former is a saccharolytic fermenter, whereas the latter is an oxidizer of carboxylic acids. Together, they may form a syntrophic network for partitioning of metabolic resources. Both species possessed numerous genes [type 6 secretion systems, repeats in toxin (RTX) toxins, RHS proteins, adhesins, and type IV pili] that likely mediate cell-cell interactions and gut colonization. Variation in these genes could account for the host fidelity of strains observed in previous phylogenetic studies. Here, we also show the first experimental evidence, to our knowledge, for this specificity in vivo: Strains of S. alvi were able to colonize their native bee host but not bees of another genus. Consistent with specific, long-term host association, comparative genomic analysis revealed a deep divergence and little or no gene flow between Apis and Bombus gut symbionts. However, within a host type (Apis or Bombus), we detected signs of horizontal gene transfer between G. apicola and S. alvi, demonstrating the importance of the broader gut community in shaping the evolution of any one member. Our results show that host specificity is likely driven by multiple factors, including direct host-microbe interactions, microbe-microbe interactions, and social transmission.

  3. Contemporary human-altered landscapes and oceanic barriers reduce bumble bee gene flow.

    PubMed

    Jha, S

    2015-03-01

    Much of the world's terrestrial landscapes are being altered by humans in the form of agriculture, urbanization and pastoral systems, with major implications for biodiversity. Bumble bees are one of the most effective pollinators in both natural and cultivated landscapes, but are often the first to be extirpated in human-altered habitats. Yet, little is known about the role of natural and human-altered habitats in promoting or limiting bumble bee gene flow. In this study, I closely examine the genetic structure of the yellow-faced bumble bee, Bombus vosnesenskii, across the southwestern US coast and find strong evidence that natural oceanic barriers, as well as contemporary human-altered habitats, limit bee gene flow. Heterozygosity and allelic richness were lower in island populations, while private allelic richness was higher in island populations compared to mainland populations. Genetic differentiation, measured for three indices across the 1000 km study region, was significantly greater than the null expectation (F(ST) = 0.041, F'(ST) = 0.044 and D(est) = 0.155) and correlated with geographic distance. Furthermore, genetic differentiation patterns were most strongly correlated with contemporary (2011) not past (2006, 2001) resistance maps calibrated for high dispersal limitation over oceans, impervious habitat and croplands. Despite the incorporation of dramatic elevation gradients, the analyses reveal that oceans and contemporary human land use, not mountains, are the primary dispersal barriers for B. vosnesenskii gene flow. These findings reinforce the importance of maintaining corridors of suitable habitat across the distribution range of native pollinators to promote their persistence and safeguard their ability to provide essential pollination services.

  4. Fine-scale spatial genetic structure of common and declining bumble bees across an agricultural landscape.

    PubMed

    Dreier, Stephanie; Redhead, John W; Warren, Ian A; Bourke, Andrew F G; Heard, Matthew S; Jordan, William C; Sumner, Seirian; Wang, Jinliang; Carvell, Claire

    2014-07-01

    Land-use changes have threatened populations of many insect pollinators, including bumble bees. Patterns of dispersal and gene flow are key determinants of species' ability to respond to land-use change, but have been little investigated at a fine scale (<10 km) in bumble bees. Using microsatellite markers, we determined the fine-scale spatial genetic structure of populations of four common Bombus species (B. terrestris, B. lapidarius, B. pascuorum and B. hortorum) and one declining species (B. ruderatus) in an agricultural landscape in Southern England, UK. The study landscape contained sown flower patches representing agri-environment options for pollinators. We found that, as expected, the B. ruderatus population was characterized by relatively low heterozygosity, number of alleles and colony density. Across all species, inbreeding was absent or present but weak (FIS  = 0.01-0.02). Using queen genotypes reconstructed from worker sibships and colony locations estimated from the positions of workers within these sibships, we found that significant isolation by distance was absent in B. lapidarius, B. hortorum and B. ruderatus. In B. terrestris and B. pascuorum, it was present but weak; for example, in these two species, expected relatedness of queens founding colonies 1 m apart was 0.02. These results show that bumble bee populations exhibit low levels of spatial genetic structure at fine spatial scales, most likely because of ongoing gene flow via widespread queen dispersal. In addition, the results demonstrate the potential for agri-environment scheme conservation measures to facilitate fine-scale gene flow by creating a more even distribution of suitable habitats across landscapes. © 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  5. Honey bee (Hymenoptera: Apidae) distribution and potential for supplementary pollination in commercial tomato greenhouses during winter.

    PubMed

    Higo, Heather A; Rice, Nathan D; Winston, Mark L; Lewis, Bob

    2004-04-01

    This study examined the use of honey bees, Apis mellifera L., to supplement bumble bee, Bombus spp., pollination in commercial tomato, Lycopersicon esculentum Miller, greenhouses in Western Canada. Honey bee colonies were brought into greenhouses already containing bumble bees and left for 1 wk to acclimatize. The following week, counts of honey and bumble bees foraging and flying throughout the greenhouse were conducted three times per day, and tomato flowers open during honey bee pollination were marked for later fruit harvest. The same counts and flower-marking also were done before and after the presence of honey bees to determine the background level of bumble bee pollination. Overall, tomato size was not affected by the addition of honey bees, but in one greenhouse significantly larger tomatoes were produced with honey bees present compared with bumble bees alone. In that greenhouse, honey bee foraging was greater than in the other greenhouses. Honey bees generally foraged within 100 m of their colony in all greenhouses. Our study invites further research to examine the use of honey bees with reduced levels of bumble bees, or as sole pollinators of greenhouse tomatoes. We also make specific recommendations for how honey bees can best be managed in greenhouses.

  6. The correlation of learning speed and natural foraging success in bumble-bees.

    PubMed

    Raine, Nigel E; Chittka, Lars

    2008-04-07

    Despite the widespread assumption that the learning abilities of animals are adapted to the particular environments in which they operate, the quantitative effects of learning performance on fitness remain virtually unknown. Here, we evaluate the learning performance of bumble-bees (Bombus terrestris) from multiple colonies in an ecologically relevant associative learning task under laboratory conditions, before testing the foraging performance of the same colonies under the field conditions. We demonstrate that variation in learning speed among bumble-bee colonies is directly correlated with the foraging performance, a robust fitness measure, under natural conditions. Colonies vary in learning speed by a factor of nearly five, with the slowest learning colonies collecting 40% less nectar than the fastest learning colonies. Such a steep fitness function is suggestive of strong selection for higher learning speed. Partial correlation analysis reveals that other factors such as forager body size or colour preference appear to be negligible in our study. Although our study does not directly prove causality of learning on foraging success, our approach of correlating natural within-species variation in these two factors represents a major advance over traditional between-species correlative analyses where comparability can be compromised by the fact that species vary along multiple dimensions.

  7. The corbiculate bees arose from New World oil-collecting bees: implications for the origin of pollen baskets.

    PubMed

    Martins, Aline C; Melo, Gabriel A R; Renner, Susanne S

    2014-11-01

    The economically most important group of bees is the "corbiculates", or pollen basket bees, some 890 species of honeybees (Apis), bumblebees (Bombus), stingless bees (Meliponini), and orchid bees (Euglossini). Molecular studies have indicated that the corbiculates are closest to the New World genera Centris, with 230 species, and Epicharis, with 35, albeit without resolving the precise relationships. Instead of concave baskets, these bees have hairy hind legs on which they transport pollen mixed with floral oil, collected with setae on the anterior and middle legs. We sampled two-thirds of all Epicharis, a third of all Centris, and representatives of the four lineages of corbiculates for four nuclear gene regions, obtaining a well-supported phylogeny that has the corbiculate bees nested inside the Centris/Epicharis clade. Fossil-calibrated molecular clocks, combined with a biogeographic reconstruction incorporating insights from the fossil record, indicate that the corbiculate clade arose in the New World and diverged from Centris 84 (72-95)mya. The ancestral state preceding corbiculae thus was a hairy hind leg, perhaps adapted for oil transport as in Epicharis and Centris bees. Its replacement by glabrous, concave baskets represents a key innovation, allowing efficient transport of plant resins and large pollen/nectar loads and freeing the corbiculate clade from dependence on oil-offering flowers. The transformation could have involved a novel function of Ubx, the gene known to change hairy into smooth pollen baskets in Apis and Bombus.

  8. Conservation genetics, foraging distance and nest density of the scarce Great Yellow Bumblebee (Bombus distinguendus).

    PubMed

    Charman, Thomas G; Sears, Jane; Green, Rhys E; Bourke, Andrew F G

    2010-07-01

    The conservation genetics of bees is of particular interest because many bee species are in decline, so jeopardizing the essential ecosystem service of plant pollination that they provide. In addition, as social haplodiploids, inbred bees may be vulnerable to the extra genetic load represented by the production of sterile diploid males. Using microsatellite markers, we investigated the genetic structure of populations of the Great Yellow Bumblebee (Bombus distinguendus Morawitz) in the UK, where this species has undergone a precipitous decline. By means of a mixture of analytical methods and simulation, we also extended--and then applied--genetic methods for estimating foraging distance and nest density in wild bees. B. distinguendus populations were characterized by low expected heterozygosity and allelic richness, inbreeding coefficients not significantly different from zero, absence of detected diploid males, absence of substantial demographic bottlenecking, and population substructuring at large (c. 100+ km) but not small (10s of km) spatial scales. The minimum average effective population size at our sampling sites was low (c. 25). In coastal grassland (machair), the estimated modal foraging distance of workers was 391 m, with 95% of foraging activity occurring within 955 m of the nest, and estimated nest density was 19.3 nests km(-2). These findings show that B. distinguendus exhibits some genetic features of scarce, declining or fragmented populations. Moreover, B. distinguendus workers appear to forage over above-average distances and nests remain thinly distributed even in current strongholds. These considerations should inform future conservation actions for this and similar species.

  9. A conserved class of queen pheromones? Re-evaluating the evidence in bumblebees (Bombus impatiens)

    PubMed Central

    Amsalem, Etya; Orlova, Margarita; Grozinger, Christina M.

    2015-01-01

    The regulation of reproductive division of labour is a key component in the evolution of social insects. Chemical signals are important mechanisms to regulate worker reproduction, either as queen-produced pheromones that coercively inhibit worker reproduction or as queen signals that honestly advertise her fecundity. A recent study suggested that a conserved class of hydrocarbons serve as queen pheromones across three independent origins of eusociality. In bumblebees (Bombus terrestris), pentacosane (C25) was suggested to serve as a queen pheromone. Here, we repeat these studies using a different species of bumblebee (Bombus impatiens) with a more controlled experimental design. Instead of dequeened colonies, we used same-aged, three-worker queenless groups comprising either experienced or naive workers (with/without adult exposure to queen pheromone). We quantified three hydrocarbons (C23, C25 and C27) on the cuticular surfaces of females and tested their effects on the two worker types. Our results indicate differences in responses of naive and experienced workers, genetic effects on worker reproduction, and general effects of hydrocarbons and duration of egg laying on ovary resorption rates. However, we found no evidence to support the theory that a conserved class of hydrocarbons serve as queen pheromones or queen signals in Bombus impatiens. PMID:26490791

  10. A conserved class of queen pheromones? Re-evaluating the evidence in bumblebees (Bombus impatiens).

    PubMed

    Amsalem, Etya; Orlova, Margarita; Grozinger, Christina M

    2015-10-22

    The regulation of reproductive division of labour is a key component in the evolution of social insects. Chemical signals are important mechanisms to regulate worker reproduction, either as queen-produced pheromones that coercively inhibit worker reproduction or as queen signals that honestly advertise her fecundity. A recent study suggested that a conserved class of hydrocarbons serve as queen pheromones across three independent origins of eusociality. In bumblebees (Bombus terrestris), pentacosane (C25) was suggested to serve as a queen pheromone. Here, we repeat these studies using a different species of bumblebee (Bombus impatiens) with a more controlled experimental design. Instead of dequeened colonies, we used same-aged, three-worker queenless groups comprising either experienced or naive workers (with/without adult exposure to queen pheromone). We quantified three hydrocarbons (C23, C25 and C27) on the cuticular surfaces of females and tested their effects on the two worker types. Our results indicate differences in responses of naive and experienced workers, genetic effects on worker reproduction, and general effects of hydrocarbons and duration of egg laying on ovary resorption rates. However, we found no evidence to support the theory that a conserved class of hydrocarbons serve as queen pheromones or queen signals in Bombus impatiens. © 2015 The Author(s).

  11. Bee Pollen

    MedlinePlus

    ... nectar and bee saliva. Pollens come from many plants, so the contents of bee pollen can vary ... joint pain (rheumatism), painful urination, prostate conditions, and radiation ... or other ingredients in bee pollen are effective as treatment.

  12. Bee poison

    MedlinePlus

    ... is caused by a sting from a bee, wasp , or yellow jacket. This article is for information ... Bee, wasp, and yellow jacket stings contain a substance called venom. Africanized bee colonies are very sensitive to being ...

  13. Comparing bee species responses to chemical mixtures: Common response patterns?

    PubMed Central

    Lahive, Elma; Horton, Alice A.; Svendsen, Claus; Rortais, Agnes; Dorne, Jean Lou; Baas, Jan; Heard, Matthew S.; Spurgeon, David J.

    2017-01-01

    Pollinators in agricultural landscapes can be exposed to mixtures of pesticides and environmental pollutants. Existing mixture toxicity modelling approaches, such as the models of concentration addition and independent action and the mechanistic DEBtox framework have been previously shown as valuable tools for understanding and ultimately predicting joint toxicity. Here we apply these mixture models to investigate the potential to interpret the effects of semi-chronic binary mixture exposure for three bee species: Apis mellifera, Bombus terrestris and Osmia bicornis within potentiation and mixture toxicity experiments. In the potentiation studies, the effect of the insecticide dimethoate with added propiconazole fungicide and neonicotinoid insecticide clothianidin with added tau-fluvalinate pyrethroid acaricide showed no difference in toxicity compared to the single chemical alone. Clothianidin toxicity showed a small scale, but temporally conserved increase in exposure conducted in the presence of propiconazole, particularly for B. terrestris and O. bicornis, the latter showing a near three-fold increase in clothianidin toxicity in the presence of propiconazole. In the mixture toxicity studies, the dominant response patterns were of additivity, however, binary mixtures of clothianidin and dimethoate in A. mellifera, B. terrestris and male O. bicornis there was evidence of a predominant antagonistic interaction. Given the ubiquitous nature of exposures to multiple chemicals, there is an urgent need to consider mixture effects in pollinator risk assessments. Our analyses suggest that current models, particularly those that utilise time-series data, such as DEBtox, can be used to identify additivity as the dominant response pattern and also those examples of interactions, even when small-scale, that may need to be taken into account during risk assessment. PMID:28640811

  14. Annual dynamics of wild bee densities: attractiveness and productivity effects of oilseed rape.

    PubMed

    Riedinger, Verena; Mitesser, Oliver; Hovestadt, Thomas; Steffan-Dewenter, Ingolf; Holzschuh, Andrea

    2015-05-01

    Mass-flowering crops may affect long-term population dynamics, but effects on pollinators have never been studied across several years. We monitored wild bees in oilseed rape fields in 16 landscapes in Germany in two consecutive years. Effects on bee densities of landscape oilseed rape cover in the years of monitoring and in the previous years were evaluated with landscape data from three consecutive years. We fit empirical data to a mechanistic model to provide estimates for oilseed rape attractiveness and its effect on bee productivity in comparison to the rest of the landscape, and we evaluated consequences for pollinator densities in consecutive years. Our results show that high oilseed rape cover in the previous year enhances current densities of wild bees (except for bumble bees). Moreover, we show a strong attractiveness of and dilution on (i.e., decreasing bee densities with increasing landscape oilseed rape cover) oilseed rape for bees during flowering in the current year, modifying the effect of the previous year's oilseed rape cover in the case of wild bees (excluding Bombus). As long as other factors such as nesting sites or natural enemies do not limit bee reproduction, our findings suggest long-term positive effects of mass-flowering crops on bee populations, at least for non-Bombus generalists, which possibly help to maintain crop pollination services even when crop area increases. Similar effects are conceivable for other organisms providing ecosystem services in annual crops and should be considered in future studies.

  15. Field study results on the probability and risk of a horizontal gene transfer from transgenic herbicide-resistant oilseed rape pollen to gut bacteria of bees.

    PubMed

    Mohr, Kathrin I; Tebbe, Christoph C

    2007-06-01

    Bees are specifically subjected to intimate contacts with transgenic plants due to their feeding activities on pollen. In this study, the probability and ecological risk of a gene transfer from pollen to gut bacteria of bees was investigated with larvae of Apis mellifera (honeybee), Bombus terrestris (bumblebee), and Osmia bicornis (red mason bee), all collected at a flowering transgenic oilseed rape field. The plants were genetically engineered with the pat-gene, conferring resistance against glufosinate (syn. phosphinothricin), a glutamine-synthetase inhibitor in plants and microorganisms. Ninety-six bacterial strains were isolated and characterized by 16S rRNA gene sequencing, revealing that Firmicutes represented 58% of the isolates, Actinobacteria 31%, and Proteobacteria 11%, respectively. Of all isolates, 40% were resistant to 1 mM glufosinate, and 11% even to 10 mM. Resistant phenotypes were found in all phylogenetic groups. None of the resistant phenotypes carried the recombinant pat-gene in its genome. The threshold of detecting gene transfer in this field study was relatively insensitive due to the high background of natural glufosinate resistance. However, the broad occurrence of glufosinate-resistant bacteria from different phylogenetic groups suggests that rare events of horizontal gene transfer will not add significantly to natural bacterial glufosinate resistance.

  16. Bumble bee (Hymenoptera: Apidae) community structure on two sagebrush steppe sites in southern Idaho

    Treesearch

    Stephen P. Cook; Sara M. Birch; Frank W. Merickel; Carrie Caselton Lowe; Deborah Page-Dumroese

    2011-01-01

    Although sagebrush, Artemisia spp., does not require an insect pollinator, there are several native species of bumble bees, Bombus spp. (Hymenoptera: Apidae), that are present in sagebrush steppe ecosystems where they act as pollinators for various forbs and shrubs. These native pollinators contribute to plant productivity and reproduction. We captured 12 species of...

  17. The neonicotinoid pesticide, imidacloprid, affects Bombus impatiens (bumblebee) sonication behavior when consumed at doses below the LD50.

    PubMed

    Switzer, Callin M; Combes, Stacey A

    2016-08-01

    We investigated changes in sonication (or buzz-pollination) behavior of Bombus impatiens bumblebees, after consumption of the neonicotinoid pesticide, imidacloprid. We measured sonication frequency, sonication length, and flight (wing beat) frequency of marked bees collecting pollen from Solanum lycopsersicum (tomato), and then randomly assigned bees to consume 0, 0.0515, 0.515, or 5.15 ng of imidacloprid. We recorded the number of bees in each treatment group that resumed sonication behavior after consuming imidacloprid, and re-measured sonication and flight behavior for these bees. We did not find evidence that consuming 0.0515 ng imidacloprid affected the sonication length, sonication frequency, or flight frequency for bees that sonicated after consuming imidacloprid; we were unable to test changes in these variables for bees that consumed 0.515 or 5.15 ng because we did not observe enough of these bees sonicating after treatment. We performed Cox proportional hazard regression to determine whether consuming imidacloprid affected the probability of engaging in further sonication behavior on S. lycopersicum and found that bumblebees who consumed 0.515 or 5.15 ng of imidacloprid were significantly less likely to sonicate after treatment than bees who consumed no imidacloprid. At the end of the experiment, we classified bees as dead or alive; our data suggest a trend of increasing mortality with higher doses of imidacloprid. Our results show that even modest doses of imidacloprid can significantly affect the likelihood of bumblebees engaging in sonication, a behavior critical for the pollination of a variety of crops and other plants.

  18. Impact of currently used or potentially useful insecticides for canola agroecosystems on Bombus impatiens (Hymenoptera: Apidae), Megachile rotundata (Hymentoptera: Megachilidae), and Osmia lignaria (Hymenoptera: Megachilidae).

    PubMed

    Scott-Dupree, C D; Conroy, L; Harris, C R

    2009-02-01

    Pest management practices may be contributing to a decline in wild bee populations in or near canola (Brassica napus L.) agroecosystems. The objective of this study was to investigate the direct contact toxicity of five technical grade insecticides--imidacloprid, clothianidin, deltamethrin, spinosad, and novaluron--currently used, or with potential for use in canola integrated pest management on bees that may forage in canola: common eastern bumble bees [Bombus impatiens (Cresson); hereafter bumble bees], alfalfa leafcutting bees [Megachile rotundata (F.)], and Osmia lignaria Cresson. Clothianidin and to a lesser extent imidacloprid were highly toxic to all three species, deltamethrin and spinosad were intermediate in toxicity, and novaluron was nontoxic. Bumble bees were generally more tolerant to the direct contact applications > O. lignaria > leafcutting bees. However, differences in relative toxicities between the three species were not consistent, e.g., whereas clothianidin was only 4.9 and 1.3x more toxic, deltamethrin was 53 and 68x more toxic to leafcutting bees than to bumble bees and O. lignaria, respectively. Laboratory assessment of direct contact toxicity, although useful, is only one measure of potential impact, and mortality under field conditions may differ greatly depending on management practices. Research conducted using only honey bees as the indicator species may not adequately reflect the risk posed by insecticides to wild bees because of their unique biology and differential susceptibility. Research programs focused on determining nontarget impact on pollinators should be expanded to include not only the honey bee but also wild bee species representative of the agricultural system under investigation.

  19. Long-term prevalence of the protists Crithidia bombi and Apicystis bombi and detection of the microsporidium Nosema bombi in invasive bumble bees.

    PubMed

    Plischuk, Santiago; Antúnez, Karina; Haramboure, Marina; Minardi, Graciela M; Lange, Carlos E

    2017-04-01

    An initial survey in 2009 carried out at a site in northwestern Patagonia region, Argentina, revealed for the first time in South America the presence of the flagellate Crithidia bombi and the neogregarine Apicystis bombi, two pathogens associated with the Palaearctic invasive bumble bee Bombus terrestris. In order to determine the long-term persistence and dynamics of this microparasite complex, four additional collections at the same site (San Carlos de Bariloche) were conducted along the following seven years. Both protists were detected in all collections: prevalence was 2%-21.6% for C. bombi and 1.2%-14% for A. bombi. In addition, the microsporidium Nosema bombi was recorded for the first time in the country in the last two collections, at prevalences of 12.4% and 2.4% and unusually high infection intensities (Average = 6.56 × 10(7) spores per individual). Due to the exceptional dispersal ability of the exotic B. terrestris, these three multihost pathogens should be considered as potential threats to South American native bumble bees.

  20. Host manipulation of bumble bee queens by Sphaerularia nematodes indirectly affects foraging of non-host workers.

    PubMed

    Kadoya, Eri Z; Ishii, Hiroshi S

    2015-05-01

    Sphaerularia bombi Dufour is a major parasite of bumble bee queens that manipulates its host's behavior: parasitized queens do not breed and found nests but continue to fly into the early summer months. We examined the indirect consequences of this host manipulation on non-host workers in central Hokkaido Island, Japan. In this area, parasitism of Bombus terrestris by S. bombi is common but does not affect every queen; therefore, as summer begins, B. terrestris queens continue to dominate some flower patches and disappear from others. At sites dominated by parasitized queens, we found that the nectar standing crop of red clover was smaller, B. terrestris workers carried out fewer legitimate visits to red clover and more nectar robberies, and the workers were smaller than at other sites. Removing queens from a site increased the nectar standing crop of red clover, the frequency of worker visits to red clover, and the size of the workers. These results suggest that host manipulation by S. bombi increased competition for flower resources among host queens and non-host workers and altered the interaction between plants and non-host flower visitors.

  1. Microbial Communities of Three Sympatric Australian Stingless Bee Species

    PubMed Central

    Leonhardt, Sara D.; Kaltenpoth, Martin

    2014-01-01

    Bacterial symbionts of insects have received increasing attention due to their prominent role in nutrient acquisition and defense. In social bees, symbiotic bacteria can maintain colony homeostasis and fitness, and the loss or alteration of the bacterial community may be associated with the ongoing bee decline observed worldwide. However, analyses of microbiota associated with bees have been largely confined to the social honeybees (Apis mellifera) and bumblebees (Bombus spec.), revealing – among other taxa – host-specific lactic acid bacteria (LAB, genus Lactobacillus) that are not found in solitary bees. Here, we characterized the microbiota of three Australian stingless bee species (Apidae: Meliponini) of two phylogenetically distant genera (Tetragonula and Austroplebeia). Besides common plant bacteria, we find LAB in all three species, showing that LAB are shared by honeybees, bumblebees and stingless bees across geographical regions. However, while LAB of the honeybee-associated Firm4–5 clusters were present in Tetragonula, they were lacking in Austroplebeia. Instead, we found a novel clade of likely host-specific LAB in all three Australian stingless bee species which forms a sister clade to a large cluster of Halictidae-associated lactobacilli. Our findings indicate both a phylogenetic and geographical signal of host-specific LAB in stingless bees and highlight stingless bees as an interesting group to investigate the evolutionary history of the bee-LAB association. PMID:25148082

  2. Microbial communities of three sympatric Australian stingless bee species.

    PubMed

    Leonhardt, Sara D; Kaltenpoth, Martin

    2014-01-01

    Bacterial symbionts of insects have received increasing attention due to their prominent role in nutrient acquisition and defense. In social bees, symbiotic bacteria can maintain colony homeostasis and fitness, and the loss or alteration of the bacterial community may be associated with the ongoing bee decline observed worldwide. However, analyses of microbiota associated with bees have been largely confined to the social honeybees (Apis mellifera) and bumblebees (Bombus spec.), revealing--among other taxa--host-specific lactic acid bacteria (LAB, genus Lactobacillus) that are not found in solitary bees. Here, we characterized the microbiota of three Australian stingless bee species (Apidae: Meliponini) of two phylogenetically distant genera (Tetragonula and Austroplebeia). Besides common plant bacteria, we find LAB in all three species, showing that LAB are shared by honeybees, bumblebees and stingless bees across geographical regions. However, while LAB of the honeybee-associated Firm4-5 clusters were present in Tetragonula, they were lacking in Austroplebeia. Instead, we found a novel clade of likely host-specific LAB in all three Australian stingless bee species which forms a sister clade to a large cluster of Halictidae-associated lactobacilli. Our findings indicate both a phylogenetic and geographical signal of host-specific LAB in stingless bees and highlight stingless bees as an interesting group to investigate the evolutionary history of the bee-LAB association.

  3. Bombus impatiens (Hymenoptera: Apidae): an alternative to Apis mellifera (Hymenoptera: Apidae) for lowbush blueberry pollination.

    PubMed

    Stubbs, C S; Drummond, F A

    2001-06-01

    The pollination effectiveness of the commercially reared bumble bee Bombus impatiens Cresson, was compared in field studies to the honey bee, Apis mellifera L., for lowbush blueberry, Vaccinium angustifolium Ait. A preliminary study indicated that B. impatiens had potential as an alternative pollinator. In a 3-yr study, percentage fruit set, percentage harvested berries, berry weight, and seeds per berry were compared in blueberry fields stocked at 7.5 A. mellifera hives per hectare to 5, 7.5, or 10 B. impatiens colonies per hectare. Percentage of harvested berries (yield) was significantly higher in fields stocked with B. impatiens at 10 colonies per hectare. No other parameters measuring pollinator effectiveness were significantly different at 5, 7.5, or 10 colonies per hectare. Flower handling time was significantly faster for B. impatiens and it more frequently collected blueberry pollen. All parameters of pollinator effectiveness were similar for B. impatiens, A. mellifera, and native wild bees in a follow-up study. Overall, B. impatiens was a suitable alternative to A. mellifera.

  4. Performance of Apis mellifera, Bombus impatiens, and Peponapis pruinosa (Hymenoptera: Apidae) as pollinators of pumpkin.

    PubMed

    Artz, Derek R; Nault, Brian A

    2011-08-01

    Pollination services of pumpkin, Cucurbita pepo L., provided by the European honey bee, Apis mellifera L., were compared with two native bee species, the common eastern bumble bee, Bombus impatiens (Cresson), and Peponapis pruinosa Say, in New York from 2008 to 2010. Performance of each species was determined by comparing single-visit pollen deposition, percentage of visits that contacted the stigma, flower-handling time, fruit and seed set, and fruit weight per number of visits. Fruit yield from small fields (0.6 ha) supplemented with commercial B. impatiens colonies was compared with yield from those not supplemented. A. mellifera spent nearly 2 and 3 times longer foraging on each pistillate flower compared with B. impatiens and P. pruinosa, respectively. A. mellifera also visited pistillate flowers 10-20 times more frequently than B. impatiens and P. pruinosa, respectively. Yet, B. impatiens deposited 3 times more pollen grains per stigma and contacted stigmas significantly more often than either A. mellifera or P. pruinosa. Fruit set and weight from flowers visited four to eight times by B. impatiens were similar to those from open-pollinated flowers, whereas flowers pollinated by A. mellifera and P. pruinosa produced fewer fruit and smaller fruit compared with those from open-pollinated flowers. Fields supplemented with B. impatiens produced significantly more pumpkins per plant than nonsupplemented fields. B. impatiens was a better pollinator of pumpkin than P. pruinosa and should be considered as a promising alternative to A. mellifera for pollinating this crop.

  5. Applying geographic profiling used in the field of criminology for predicting the nest locations of bumble bees.

    PubMed

    Suzuki-Ohno, Yukari; Inoue, Maki N; Ohno, Kazunori

    2010-07-21

    We tested whether geographic profiling (GP) can predict multiple nest locations of bumble bees. GP was originally developed in the field of criminology for predicting the area where an offender most likely resides on the basis of the actual crime sites and the predefined probability of crime interaction. The predefined probability of crime interaction in the GP model depends on the distance of a site from an offender's residence. We applied GP for predicting nest locations, assuming that foraging and nest sites were the crime sites and the offenders' residences, respectively. We identified the foraging and nest sites of the invasive species Bombus terrestris in 2004, 2005, and 2006. We fitted GP model coefficients to the field data of the foraging and nest sites, and used GP with the fitting coefficients. GP succeeded in predicting about 10-30% of actual nests. Sensitivity analysis showed that the predictability of the GP model mainly depended on the coefficient value of buffer zone, the distance at the mode of the foraging probability. GP will be able to predict the nest locations of bumble bees in other area by using the fitting coefficient values measured in this study. It will be possible to further improve the predictability of the GP model by considering food site preference and nest density.

  6. Responses of social and solitary bees to pulsed floral resources.

    PubMed

    Crone, Elizabeth E

    2013-10-01

    Pulsed food resources lead to mismatches between distribution of consumers and resources in space and time. Many studies have investigated how pollinators and floral resources covary in space, but few have looked at their covariance among years. I studied responses of two bee taxa, Bombus (a social genus) and Anthophora (a solitary genus), to variation in flowering by Astragalus scaphoides, a perennial herb that flowers in alternate years. First, I quantified the rate at which individual plants were visited by bees. Anthophora showed evidence of a demographic response to resource pulses--that is, more individuals were seen in the year after a high-flowering year--whereas Bombus did not. Second, I quantified pollinator behavior by following individual bees and recording the proportion of visits to A. scaphoides within single foraging bouts. The proportion of visits to A. scaphoides by both taxa increased with A. scaphoides's flowering density. Higher specialization in high-flowering years likely makes both taxa better pollinators in high-flowering years. If these taxa differ in effectiveness as pollinators, then these responses translate into variation in pollination services in space and time, specifically, more activity by Bombus in high-flowering years and more by Anthophora in years following high-flowering years. They also emphasize that pollinator activity depends in part on past-as well as current-floral resources.

  7. Evidence for Bombus occidentalis (Hymenoptera: Apidae) Populations in the Olympic Peninsula, the Palouse Prairie, and Forests of Northern Idaho

    PubMed Central

    Rhoades, Paul R.; Koch, Jonathan B.; Waits, Lisette P.; Strange, James P.; Eigenbrode, Sanford D.

    2016-01-01

    Since the mid-1990s, Bombus occidentalis (Green) has declined from being one of the most common to one of the rarest bumble bee species in the Pacific Northwest of the United States. Although its conservation status is unresolved, a petition to list this species as endangered or threatened was recently submitted to the U.S. Fish and Wildlife Service. To shed light on the conservation situation and inform the U.S. Fish and Wildlife Service decision, we report on the detection and abundance of B. occidentalis following bumble bee collection between 2012 and 2014 across the Pacific Northwest. Collection occurred from the San Juan Islands and Olympic peninsula east to northern Idaho and northeastern Oregon, excluding the arid region in central Washington. B. occidentalis was observed at 23 collection sites out of a total of 234. With the exception of three sites on the Olympic peninsula, all of these were in the southeastern portion of the collection range. PMID:26856817

  8. Identification of Aspergillus nomius in Bees Visiting Brazil Nut Flowers

    PubMed Central

    Massi, Fernanda Pelisson; Penha, Rafael Elias Silva; Cavalcante, Marcelo Casimiro; Viaro, Helena Paula; da Silva, Josué José; de Souza Ferranti, Larissa; Fungaro, Maria Helena Pelegrinelli

    2015-01-01

    We designed a primer pair (BtubNomF/BtubNomR) specifically for amplifying Aspergillus nomius DNA. In vitro assays confirmed BtubNomF/BtubNomR specificity, corroborating its usefulness in detecting and identifying A. nomius. We then investigated the occurrence of A. nomius in floral visitors of Bertholletia excelsa trees by means of PCR, and A. nomius was detected in the following bees: Xylocopa frontalis, Bombus transversalis, Centris denudans, C. ferruginea, and Epicharis flava. The presence of A. nomius in bees visiting Brazil nuts opens up new avenues for obtaining novel insights into the process whereby Brazil nuts are contaminated by aflatoxin-producing fungi. PMID:26063353

  9. Identification of Aspergillus nomius in Bees Visiting Brazil Nut Flowers.

    PubMed

    Massi, Fernanda Pelisson; Penha, Rafael Elias Silva; Cavalcante, Marcelo Casimiro; Viaro, Helena Paula; da Silva, Josué José; de Souza Ferranti, Larissa; Fungaro, Maria Helena Pelegrinelli

    2015-01-01

    We designed a primer pair (BtubNomF/BtubNomR) specifically for amplifying Aspergillus nomius DNA. In vitro assays confirmed BtubNomF/BtubNomR specificity, corroborating its usefulness in detecting and identifying A. nomius. We then investigated the occurrence of A. nomius in floral visitors of Bertholletia excelsa trees by means of PCR, and A. nomius was detected in the following bees: Xylocopa frontalis, Bombus transversalis, Centris denudans, C. ferruginea, and Epicharis flava. The presence of A. nomius in bees visiting Brazil nuts opens up new avenues for obtaining novel insights into the process whereby Brazil nuts are contaminated by aflatoxin-producing fungi.

  10. Estimation of the fructose diphosphatase–phosphofructokinase substrate cycle in the flight muscle of Bombus affinis

    PubMed Central

    Clark, Michael G.; Bloxham, David P.; Holland, Paul C.; Lardy, Henry A.

    1973-01-01

    1. Substrate cycling of fructose 6-phosphate through reactions catalysed by phosphofructokinase and fructose diphosphatase was estimated in bumble-bee (Bombus affinis) flight muscle in vivo. 2. Estimations of substrate cycling of fructose 6-phosphate and of glycolysis were made from the equilibrium value of the 3H/14C ratio in glucose 6-phosphate as well as the rate of 3H release to water after the metabolism of [5-3H,U-14C]glucose. 3. In flight, the metabolism of glucose proceeded exclusively through glycolysis (20.4μmol/min per g fresh wt.) and there was no evidence for substrate cycling. 4. In the resting bumble-bee exposed to low temperatures (5°C), the pattern of glucose metabolism in the flight muscle was altered so that substrate cycling was high (10.4μmol/min per g fresh wt.) and glycolysis was decreased (5.8μmol/min per g fresh wt.). 5. The rate of substrate cycling in the resting bumble-bee flight muscle was inversely related to the ambient temperature, since at 27°, 21° and 5°C the rates of substrate cycling were 0, 0.48 and 10.4μmol/min per g fresh wt. respectively. 6. Calcium ions inhibited fructose diphosphatase of the bumble-bee flight muscle at concentrations that were without effect on phosphofructokinase. The inhibition was reversed by the presence of a Ca2+-chelating compound. It is proposed that the rate of fructose 6-phosphate substrate cycling could be regulated by changes in the sarcoplasmic Ca2+ concentration associated with the contractile process. PMID:16742821

  11. Estimation of the fructose diphosphatase-phosphofructokinase substrate cycle in the flight muscle of Bombus affinis.

    PubMed

    Clark, M G; Bloxham, D P; Holland, P C; Lardy, H A

    1973-06-01

    1. Substrate cycling of fructose 6-phosphate through reactions catalysed by phosphofructokinase and fructose diphosphatase was estimated in bumble-bee (Bombus affinis) flight muscle in vivo. 2. Estimations of substrate cycling of fructose 6-phosphate and of glycolysis were made from the equilibrium value of the (3)H/(14)C ratio in glucose 6-phosphate as well as the rate of (3)H release to water after the metabolism of [5-(3)H,U-(14)C]glucose. 3. In flight, the metabolism of glucose proceeded exclusively through glycolysis (20.4mumol/min per g fresh wt.) and there was no evidence for substrate cycling. 4. In the resting bumble-bee exposed to low temperatures (5 degrees C), the pattern of glucose metabolism in the flight muscle was altered so that substrate cycling was high (10.4mumol/min per g fresh wt.) and glycolysis was decreased (5.8mumol/min per g fresh wt.). 5. The rate of substrate cycling in the resting bumble-bee flight muscle was inversely related to the ambient temperature, since at 27 degrees , 21 degrees and 5 degrees C the rates of substrate cycling were 0, 0.48 and 10.4mumol/min per g fresh wt. respectively. 6. Calcium ions inhibited fructose diphosphatase of the bumble-bee flight muscle at concentrations that were without effect on phosphofructokinase. The inhibition was reversed by the presence of a Ca(2+)-chelating compound. It is proposed that the rate of fructose 6-phosphate substrate cycling could be regulated by changes in the sarcoplasmic Ca(2+) concentration associated with the contractile process.

  12. Different toxic and hormetic responses of Bombus impatiens to Beauveria bassiana, Bacillus subtilis and spirotetramat.

    PubMed

    Ramanaidu, Krilen; Cutler, G Christopher

    2013-08-01

    Pollinator exposure to pesticides is a concern in agricultural systems that depend on pollinators for crop production. However, not all pesticides elicit toxic effects, and response to a pesticide will vary depending on dose and exposure route. The effects of biopesticide formulations of Bacillus subtilis and Beauveria bassiana and of the tetramic acid insecticide spirotetramat on the common eastern bumblebee, Bombus impatiens, were evaluated. Microcolonies of bees were exposed to field-rate or lower concentrations, and data were collected over 60 days. When ingested, field rates of spirotetramat caused high mortality after 10 days, and B. subtilis significantly reduced drone production, number of days to oviposition and number of days to drone emergence. Converse to effects observed following ingestion, topical applications of B. subtilis at concentrations less than the recommended field rate resulted in a hormetic response, with significantly increased drone production. Topical application of spirotetramat and oral or topical application of B. bassiana had no effects on bees. Spirotetramat and B. subtilis can induce adverse effects on B. impatiens, but hormetic effects following B. subtilis treatment can also occur, depending on exposure route. Additional experiments are required to determine whether similar toxic or hormetic effects occur under more realistic field conditions. © 2012 Society of Chemical Industry.

  13. Bumble bee nest abundance, foraging distance, and host-plant reproduction: implications for management and conservation.

    PubMed

    Geib, Jennifer C; Strange, James P; Galenj, Candace

    2015-04-01

    Recent reports of global declines in pollinator species imply an urgent need to assess the abundance of native pollinators and density-dependent benefits for linked plants. In this study, we investigated (1) pollinator nest distributions and estimated colony abundances, (2) the relationship between abundances of foraging workers and the number of nests they represent, (3) pollinator foraging ranges, and (4) the relationship between pollinator abundance and plant reproduction. We examined these questions in an alpine ecosystem in the Colorado Rocky Mountains, focusing on four alpine bumble bee species (Bombus balteatus, B. flavifrons, B. bifarius, and B. sylvicola), and two host plants that differ in their degrees of pollinator specialization (Trifolium dasyphyllum and T. parryi). Using microsatellites, we found that estimated colony abundances among Bombus species ranged from ~18 to 78 colonies/0.01 km2. The long-tongued species B. balteatus was most common, especially high above treeline, but the subalpine species B. bifarius was unexpectedly abundant for this elevation range. Nests detected among sampled foragers of each species were correlated with the number of foragers caught. Foraging ranges were smaller than expected for all Bombus species, ranging from 25 to 110 m. Fruit set for the specialized plant, Trifolium parryi, was positively related to the abundance of its Bombus pollinator. In contrast, fruit set for the generalized plant, T. dasyphyllum, was related to abundance of all Bombus species. Because forager abundance was related to nest abundance of each Bombus species and was an equally effective predictor of plant fecundity, forager inventories are probably suitable for assessing the health of outcrossing plant populations. However, nest abundance, rather than forager abundance, better reflects demographic and genetic health in populations of eusocial pollinators such as bumble bees. Development of models incorporating the parameters we have measured

  14. Bumble bee colony dynamics: quantifying the importance of land use and floral resources for colony growth and queen production.

    PubMed

    Crone, Elizabeth E; Williams, Neal M

    2016-04-01

    Bumble bee (Bombus) species are ecologically and economically important pollinators, and many species are in decline. In this article, we develop a mechanistic model to analyse growth trajectories of Bombus vosnesenskii colonies in relation to floral resources and land use. Queen production increased with floral resources and was higher in semi-natural areas than on conventional farms. However, the most important parameter for queen production was the colony growth rate per flower, as opposed to the average number of available flowers. This result indicates the importance of understanding mechanisms of colony growth, in order to predict queen production and enhance bumble bee population viability. Our work highlights the importance of interpreting bumble bee conservation efforts in the context of overall population dynamics and provides a framework for doing so. © 2016 John Wiley & Sons Ltd/CNRS.

  15. Quantitative Historical Change in Bumblebee (Bombus spp.) Assemblages of Red Clover Fields

    PubMed Central

    Dupont, Yoko L.; Damgaard, Christian; Simonsen, Vibeke

    2011-01-01

    Background Flower visiting insects provide a vitally important pollination service for many crops and wild plants. Recent decline of pollinating insects due to anthropogenic modification of habitats and climate, in particular from 1950's onwards, is a major and widespread concern. However, few studies document the extent of declines in species diversity, and no studies have previously quantified local abundance declines. We here make a quantitative assessment of recent historical changes in bumblebee assemblages by comparing contemporary and historical survey data. Methodology/Principal Findings We take advantage of detailed, quantitative historical survey data from the 1930's on bumblebee (Bombus spp.) abundances and species composition in red clover (Trifolium pratense) fields, an important floral resource and an attractant of all bumblebee species. We used the historical survey data as a pre-industrialization baseline, and repeated the same sampling protocol at nearly the same localities at present, hence setting up a historical experiment. We detected historical changes in abundances (bees/m2) of both workers (the “pollinatory units”) and queens (effective population size), in addition to species composition. In particular, long-tongued bumblebee species showed consistent and dramatic declines in species richness and abundances throughout the flowering season of red clover, while short-tongued species were largely unaffected. Of 12 Bombus species observed in the 1930's, five species were not observed at present. The latter were all long-tongued, late-emerging species. Conclusions/Significance Because bumblebees are important pollinators, historical changes in local bumblebee assemblages are expected to severely affect plant reproduction, in particular long-tubed species, which are pollinated by long-tongued bumblebees. PMID:21966445

  16. Quantitative historical change in bumblebee (Bombus spp.) assemblages of red clover fields.

    PubMed

    Dupont, Yoko L; Damgaard, Christian; Simonsen, Vibeke

    2011-01-01

    Flower visiting insects provide a vitally important pollination service for many crops and wild plants. Recent decline of pollinating insects due to anthropogenic modification of habitats and climate, in particular from 1950's onwards, is a major and widespread concern. However, few studies document the extent of declines in species diversity, and no studies have previously quantified local abundance declines. We here make a quantitative assessment of recent historical changes in bumblebee assemblages by comparing contemporary and historical survey data. We take advantage of detailed, quantitative historical survey data from the 1930's on bumblebee (Bombus spp.) abundances and species composition in red clover (Trifolium pratense) fields, an important floral resource and an attractant of all bumblebee species. We used the historical survey data as a pre-industrialization baseline, and repeated the same sampling protocol at nearly the same localities at present, hence setting up a historical experiment. We detected historical changes in abundances (bees/m(2)) of both workers (the "pollinatory units") and queens (effective population size), in addition to species composition. In particular, long-tongued bumblebee species showed consistent and dramatic declines in species richness and abundances throughout the flowering season of red clover, while short-tongued species were largely unaffected. Of 12 Bombus species observed in the 1930's, five species were not observed at present. The latter were all long-tongued, late-emerging species. Because bumblebees are important pollinators, historical changes in local bumblebee assemblages are expected to severely affect plant reproduction, in particular long-tubed species, which are pollinated by long-tongued bumblebees.

  17. Absence of Leishmaniinae and Nosematidae in stingless bees

    PubMed Central

    Nunes-Silva, Patrícia; Piot, Niels; Meeus, Ivan; Blochtein, Betina; Smagghe, Guy

    2016-01-01

    Bee pollination is an indispensable component of global food production and plays a crucial role in sustainable agriculture. The worldwide decline of bee populations, including wild pollinators, poses a threat to this system. However, most studies to date are situated in temperate regions where Apini and Bombini are very abundant pollinators. Tropical and subtropical regions where stingless bees (Apidae: Meliponini) are generally very common, are often overlooked. These bees also face pressure due to deforestation and agricultural intensification as well as the growing use and spread of exotic pollinators as Apis mellifera and Bombus species. The loss or decline of this important bee tribe would have a large impact on their provided ecosystem services, in both wild and agricultural landscapes. The importance of pollinator diseases, which can contribute to decline, has not been investigated so far in this bee tribe. Here we report on the first large pathogen screening of Meliponini species in southern Brazil. Remarkably we observed that there was an absence of Leishmaniinae and Nosematidae, and a very low occurrence of Apicystis bombi. Our data on disease prevalence in both understudied areas and species, can greatly improve our knowledge on the distribution of pathogens among bee species. PMID:27586080

  18. Absence of Leishmaniinae and Nosematidae in stingless bees.

    PubMed

    Nunes-Silva, Patrícia; Piot, Niels; Meeus, Ivan; Blochtein, Betina; Smagghe, Guy

    2016-09-02

    Bee pollination is an indispensable component of global food production and plays a crucial role in sustainable agriculture. The worldwide decline of bee populations, including wild pollinators, poses a threat to this system. However, most studies to date are situated in temperate regions where Apini and Bombini are very abundant pollinators. Tropical and subtropical regions where stingless bees (Apidae: Meliponini) are generally very common, are often overlooked. These bees also face pressure due to deforestation and agricultural intensification as well as the growing use and spread of exotic pollinators as Apis mellifera and Bombus species. The loss or decline of this important bee tribe would have a large impact on their provided ecosystem services, in both wild and agricultural landscapes. The importance of pollinator diseases, which can contribute to decline, has not been investigated so far in this bee tribe. Here we report on the first large pathogen screening of Meliponini species in southern Brazil. Remarkably we observed that there was an absence of Leishmaniinae and Nosematidae, and a very low occurrence of Apicystis bombi. Our data on disease prevalence in both understudied areas and species, can greatly improve our knowledge on the distribution of pathogens among bee species.

  19. Floral nectar guide patterns discourage nectar robbing by bumble bees.

    PubMed

    Leonard, Anne S; Brent, Joshua; Papaj, Daniel R; Dornhaus, Anna

    2013-01-01

    Floral displays are under selection to both attract pollinators and deter antagonists. Here we show that a common floral trait, a nectar guide pattern, alters the behavior of bees that can act opportunistically as both pollinators and as antagonists. Generally, bees access nectar via the floral limb, transporting pollen through contact with the plant's reproductive structures; however bees sometimes extract nectar from a hole in the side of the flower that they or other floral visitors create. This behavior is called "nectar robbing" because bees may acquire the nectar without transporting pollen. We asked whether the presence of a symmetric floral nectar guide pattern on artificial flowers affected bumble bees' (Bombus impatiens) propensity to rob or access nectar "legitimately." We discovered that nectar guides made legitimate visits more efficient for bees than robbing, and increased the relative frequency of legitimate visits, compared to flowers lacking nectar guides. This study is the first to show that beyond speeding nectar discovery, a nectar guide pattern can influence bees' flower handling in a way that could benefit the plant.

  20. Distribution and diversity of Nosema bombi (Microsporidia: Nosematidae) in the natural populations of bumblebees (Bombus spp.) from West Siberia.

    PubMed

    Vavilova, Valeriya; Sormacheva, Irina; Woyciechowski, Michal; Eremeeva, Natalia; Fet, Victor; Strachecka, Aneta; Bayborodin, Sergey I; Blinov, Alexander

    2015-09-01

    Nosema bombi is an obligate intracellular parasite of bumblebees (Hymenoptera, Bombus spp.), which has significant negative effect on individual bumblebees, colony fitness, and development. Recently, several new genetic variants of N. bombi without a defined taxonomic status were identified in natural bumblebee populations from Russia, China, and several European countries, as well as N. ceranae, originally isolated from honey bees, was described in bumblebee species. Thus, it is required to investigate more Nosema variability in bumblebee populations for identifying new genetic Nosema variants. In our study, we used several methods such as total DNA isolation, polymerase chain reaction (PCR) amplification, cloning, sequencing, and comparative and phylogenetic analysis to investigate a prevalence of N. bombi and its diversity in the natural populations of bumblebees across West Siberia. DNA was extracted from intestinal bumblebee tissues. Identification of the parasite was conducted, using PCR with primers specific for the ribosomal RNA gene cluster and methionine aminopeptidase 2 gene of N. bombi followed by sequencing. Seven hundred twenty-seven individual bumblebees belonging to 16 species were tested; 64 specimens revealed presence of the parasite. Prevalence of Nosema bombi infection was different in each region and varied from 4 to 20 %. No infection was found in Bombus agrorum (n = 194) and Bombus equestris (n = 132), both common bumblebees in West Siberia. Three different genetic variants of the same species, N. bombi, were identified. The first variant belonged to N. bombi (AY008373) identified by Fies et al. (J Apicult Res 40:91-96, 2001), second (N. bombi WS2) was identical to the West Siberian variant identified by Szentgyörgyi et al. (Polish Journal of Ecology 59:599-610, 2011), and the last variant, N. bombi WS3, was new. The results led us to suggest that the prevalence of the N. bombi is related to the population structure of bumblebees and

  1. Proboscis length and resource utilization in two Uruguayan bumblebees: Bombus atratus Franklin and Bombus bellicosus Smith (Hymenoptera: Apidae).

    PubMed

    Arbulo, N; Santos, E; Salvarrey, S; Invernizzi, C

    2011-01-01

    Bumblebees (Bombus sp.) are eusocial insects with an annual life cycle whose use as pollinator of crops has gained great importance in modern agriculture. Several authors have found that resource use in Bombus species is usually based on the correlation between the proboscis length of the bumblebees and the corolla depth of the flowers. The aim of this study was to determine proboscis length of Bombus atratus and B. bellicosus, two Uruguayan bumblebees, and verify the resource exploitation testing two cultivated species, the red clover and the bird's foot trefoil. Bumblebee foraging activity was recorded in two culture conditions: in a red clover and bird's foot trefoil mixed meadow, and in contiguous plots of these legumes, and the proboscis length of collected foragers was determined. Both species of bumblebees exploited red clover and bird's foot trefoil although they did it in different proportions in all instances tested. The results indicated that the choice of the resources in B. atratus and B. bellicosus was influenced by their proboscis length. Bombus atratus has a longer proboscis and preferably visited red clover, possibly obtaining nectar easier and faster than B. bellicosus, which has a shorter proboscis. Bombus bellicosus used both resources without any clear preference.

  2. Bee Abundance and Nutritional Status in Relation to Grassland Management Practices in an Agricultural Landscape.

    PubMed

    Smith, Griffin W; Debinski, Diane M; Scavo, Nicole A; Lange, Corey J; Delaney, John T; Moranz, Raymond A; Miller, James R; Engle, David M; Toth, Amy L

    2016-04-01

    Grasslands provide important resources for pollinators in agricultural landscapes. Managing grasslands with fire and grazing has the potential to benefit plant and pollinator communities, though there is uncertainty about the ideal approach. We examined the relationships among burning and grazing regimes, plant communities, and Bombus species and Apis mellifera L. abundance and nutritional indicators at the Grand River Grasslands in southern Iowa and northern Missouri. Treatment regimes included burn-only, grazed-and-burned, and patch-burn graze (pastures subdivided into three temporally distinct fire patches with free access by cattle). The premise of the experimental design was that patch-burn grazing would increase habitat heterogeneity, thereby providing more diverse and abundant floral resources for pollinators. We predicted that both bee abundance and individual bee nutritional indicators (bee size and lipid content) would be positively correlated with floral resource abundance. There were no significant differences among treatments with respect to bee abundance. However, some of the specific characteristics of the plant community showed significant relationships with bee response variables. Pastures with greater abundance of floral resources had greater bee abundance but lower bee nutritional indicators. Bee nutritional variables were positively correlated with vegetation height, but, in some cases, negatively correlated with stocking rate. These results suggest grassland site characteristics such as floral resource abundance and stocking rate are of potential importance to bee pollinators and suggest avenues for further research to untangle the complex interactions between grassland management, plant responses, and bee health.

  3. High prevalence and infection levels of Nosema ceranae in bumblebees Bombus atratus and Bombus bellicosus from Uruguay.

    PubMed

    Arbulo, N; Antúnez, K; Salvarrey, S; Santos, E; Branchiccela, B; Martín-Hernández, R; Higes, M; Invernizzi, C

    2015-09-01

    Nosema ceranae is one of the most prevalent pathogens in Apis mellifera and has recently been found in multiple host species including several species of bumblebees. Prevalence and infection intensity of N. ceranae was determined in two species of native bumblebees from Uruguay. Nosema ceranae was the only microsporidia identified and mean prevalence was 72% in Bombus atratus and 63% in Bombus bellicosus, values much higher than those reported elsewhere. The presence of this pathogen in bumblebees may be threatening not only for bumblebee populations, but also to the rest of the native pollinator community and to honeybees.

  4. Bumble bees heat up for high quality pollen.

    PubMed

    Mapalad, Katherine S; Leu, Daniel; Nieh, James C

    2008-07-01

    Thermoregulation plays a key role in bee foraging, allowing some species to forage in suboptimal temperatures. Recently, bumble bee thoracic temperature (T(th)) has been shown to increase with nectar carbohydrate content. However, pollen is also vital to bees and exhibits a greater than 20-fold range in protein quality. We provide the first demonstration that bee T(th) is also correlated with pollen quality. We allowed bumble bee, Bombus impatiens, foragers from two colonies to collect pollen varying in quality (25%, 50%, 75% and 100% by mass mixed with indigestible alpha-cellulose). We used infrared thermography to measure surface T(th) when a forager finished collecting feeder pollen and when she returned to the nest. Foragers significantly elevated their T(th) over ambient air temperature while collecting pollen and maintained this elevated T(th) upon returning to the nest. On average, foragers increased T(th) over ambient by 0.4 degrees C per 25% increase in pollen protein content. Bumble bees can therefore adjust their thoracic temperature according to pollen quality.

  5. Managing honey bees (Hymenoptera: Apidae) for greenhouse tomato pollination.

    PubMed

    Sabara, Holly A; Winston, Mark L

    2003-06-01

    Although commercially reared colonies of bumble bees (Bombus sp.) are the primary pollinator world-wide for greenhouse tomatoes (Lycopersicon esculentum Mill.) previous research indicates that honey bees (Apis mellifera L.) might be a feasible alternative or supplement to bumble bee pollination. However, management methods for honey bee greenhouse tomato pollination scarcely have been explored. We 1) tested the effect of initial amounts of brood on colony population size and flight activity in screened greenhouses during the winter, and 2) compared foraging from colonies with brood used within screened and unscreened greenhouses during the summer. Brood rearing was maintained at low levels in both brood and no-brood colonies after 21 d during the winter, and emerging honey bees from both treatments had significantly lower weights than bees from outdoor colonies. Honey bee flight activity throughout the day and over the 21 d in the greenhouse was not influenced by initial brood level. In our summer experiment, brood production in screened greenhouses neared zero after 21 d but higher levels of brood were reared in unscreened greenhouses with access to outside forage. Flower visitation measured throughout the day and over the 21 d the colonies were in the greenhouse was not influenced by screening treatment. An economic analysis indicated that managing honey bees for greenhouse tomato pollination would be financially viable for both beekeepers and growers. We conclude that honey bees can be successfully managed for greenhouse tomato pollination in both screened and unscreened greenhouses if the foraging force is maintained by replacing colonies every 3 wk.

  6. Efficiency of local Indonesia honey bees (Apis cerana L.) and stingless bee (Trigona iridipennis) on tomato (Lycopersicon esculentum Mill.) pollination.

    PubMed

    Putra, Ramadhani Eka; Kinasih, Ida

    2014-01-01

    Tomato (Lycopersicon esculentum Mill.) is considered as one of major agricultural commodity of Indonesia farming. However, monthly production is unstable due to lack of pollination services. Common pollinator agent of tomatoes is bumblebees which is unsuitable for tropical climate of Indonesia and the possibility of alteration of local wild plant interaction with their pollinator. Indonesia is rich with wild bees and some of the species already domesticated for years with prospect as pollinating agent for tomatoes. This research aimed to assess the efficiency of local honey bee (Apis cerana L.) and stingless bee (Trigona iridipennis), as pollinator of tomato. During this research, total visitation rate and total numbers of pollinated flowers by honey bee and stingless bee were compared between them with bagged flowers as control. Total fruit production, average weight and size also measured in order to correlated pollination efficiency with quantity and quality of fruit produced. Result of this research showed that A. cerana has slightly higher rate of visitation (p>0.05) and significantly shorter handling time (p < 0.05) than T. iridipennis due to their larger colony demand and low reward provide by tomato flowers. However, honey bee pollinated tomato flowers more efficient pollinator than stingless bee (80.3 and 70.2% efficiency, respectively; p < 0.05) even though the average weight and size of tomatoes were similar (p>0.05). Based on the results, it is concluded that the use of Apis cerana and Trigona spp., for pollinating tomatoes in tropical climates could be an alternative to the use of non-native Apis mellifera and bumblebees (Bombus spp.). However, more researches are needed to evaluate the cost/benefit on large-scale farming and greenhouse pollination using both bees against other bee species and pollination methods.

  7. Phenology of Bombus pennsylvanicus sonorus say (Hymenoptera: Apidae) in Central Mexico.

    PubMed

    de la Hoz, Juan Di Trani

    2006-01-01

    We studied the seasonal activity of Bombus pennsylvanicus sonorus Say in subtropical conditions of the Mexican Central Plateau. Monthly during 1998, we recorded caste of active individuals (inferred form corporal size measured as wing length), presence and activity of reproductive individuals, and mating activity. Also, we recorded the flower plants used as resources. Subtropical conditions of the Mexican Central Plateau do not seem to modify phenological features of B. pennsylvanicus sonorus since the species presents annual colonies and a clearly defined period of inactivity. The size of individuals progressively increased between the first recorded activity period in middle April and the end of the colonies in November. Reproductive bees were observed since the second half of the year. The presence of males was recorded between July and November and queens and mating pairs were observed during November and December. Then mating queens were noted seeking hibernation places. Activity resumed in February of the following year. Seasonal activity seems to be more related to availability of floral resources (which, in turn, is related to rain regime), than to changes in temperature and day length. Some of the main food resources used by B. pennsylvanicus sonorus were Tithonia tubiformis, Cosmos bipinnatus, Anoda cristata, Solanum rostratum and Jacaranda mimosaefolia.

  8. Systematical studies on the species of the subgenus Bombus (Thoracobombus) (Hymenoptera: Apidae, Bombus Latreille) in Turkey.

    PubMed

    Barkan, N P; Aytekin, A M

    2013-11-19

    The aim of this study was to analyze the 12 species which belong to the subgenus Bombus (Thoracobombus) by identifying, collating and testing the applicability of geometrics morphometrics for distinguishing the species. This was carried out on 133 females and 42 males which were collected from various localities in Turkey. After digitizing landmarks on the right fore wings, 2-dimensional Cartesian coordinates were calculated and by Procrustes analysis the coordinates were standardized and superimposed. Principal Components Analysis (PCA) and Canonical Variates Analysis (CVA) were performed to show the distribution of all species. Then, deformations which appeared in thin-plate splines were observed. Mean values of all the specimens were calculated and Sequential, Agglomerative, Hierarchical, and Nesting clustering method (SAHN) was performed with these data to obtain the dissimilarity trees. It can be concluded that all species were found to have consistently different wing shapes from each other. In females, the species B. armeniacus, B. mesomelas and B. pomorum which resemble each other, were also found to be similar based on their wing morphometry. Both in females and males, the subspecies B. sylvarum citrinofasciatus and B. sylvarum daghestanicus and the species B. humilis and B. laesus exposed high similarity in wing morphometry. In males, results showed that the species B. armeniacus and B. mesomelas and the species B. humilis and B. zonatus have very similar wing shape.

  9. Floral Nectar Guide Patterns Discourage Nectar Robbing by Bumble Bees

    PubMed Central

    Leonard, Anne S.; Brent, Joshua; Papaj, Daniel R.; Dornhaus, Anna

    2013-01-01

    Floral displays are under selection to both attract pollinators and deter antagonists. Here we show that a common floral trait, a nectar guide pattern, alters the behavior of bees that can act opportunistically as both pollinators and as antagonists. Generally, bees access nectar via the floral limb, transporting pollen through contact with the plant’s reproductive structures; however bees sometimes extract nectar from a hole in the side of the flower that they or other floral visitors create. This behavior is called “nectar robbing” because bees may acquire the nectar without transporting pollen. We asked whether the presence of a symmetric floral nectar guide pattern on artificial flowers affected bumble bees’ (Bombus impatiens) propensity to rob or access nectar “legitimately.” We discovered that nectar guides made legitimate visits more efficient for bees than robbing, and increased the relative frequency of legitimate visits, compared to flowers lacking nectar guides. This study is the first to show that beyond speeding nectar discovery, a nectar guide pattern can influence bees’ flower handling in a way that could benefit the plant. PMID:23418475

  10. Evidence for Bombus occidentalis (Hymenoptera: Apidae) Populations in the Olympic Peninsula, the Palouse Prairie, and Forests of Northern Idaho.

    PubMed

    Rhoades, Paul R; Koch, Jonathan B; Waits, Lisette P; Strange, James P; Eigenbrode, Sanford D

    2016-01-01

    Since the mid-1990s, Bombus occidentalis (Green) has declined from being one of the most common to one of the rarest bumble bee species in the Pacific Northwest of the United States. Although its conservation status is unresolved, a petition to list this species as endangered or threatened was recently submitted to the U.S. Fish and Wildlife Service. To shed light on the conservation situation and inform the U.S. Fish and Wildlife Service decision, we report on the detection and abundance of B. occidentalis following bumble bee collection between 2012 and 2014 across the Pacific Northwest. Collection occurred from the San Juan Islands and Olympic peninsula east to northern Idaho and northeastern Oregon, excluding the arid region in central Washington. B. occidentalis was observed at 23 collection sites out of a total of 234. With the exception of three sites on the Olympic peninsula, all of these were in the southeastern portion of the collection range. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

  11. Increased Acetylcholinesterase Expression in Bumble Bees During Neonicotinoid-Coated Corn Sowing

    PubMed Central

    Samson-Robert, Olivier; Labrie, Geneviève; Mercier, Pierre-Luc; Chagnon, Madeleine; Derome, Nicolas; Fournier, Valérie

    2015-01-01

    While honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. Neonicotinoids have been shown to increase acetylcholinesterase (AChE) activity in honey bees at sublethal doses. High AChE levels may therefore act as a biomarker of exposure to neonicotinoids. This two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical signs of intoxication. Bumble bee colonies (Bombus impatiens) were placed in two different agricultural cropping areas: 1) control (≥3 km from fields planted with neonicotinoid-treated seeds) or 2) exposed (within 500 m of fields planted with neonicotinoid-treated seeds), and maintained for the duration of corn sowing. As determined by Real Time qPCR, AChE mRNA expression was initially significantly higher in bumble bees from exposed sites, then decreased throughout the planting season to reach a similar endpoint to that of bumble bees from control sites. These findings suggest that exposure to neonicotinoid seed coating particles during the planting season can alter bumble bee neuronal activity. To our knowledge, this is the first study to report in situ that bumble bees living in agricultural areas exhibit signs of neonicotinoid intoxication. PMID:26223214

  12. Increased Acetylcholinesterase Expression in Bumble Bees During Neonicotinoid-Coated Corn Sowing.

    PubMed

    Samson-Robert, Olivier; Labrie, Geneviève; Mercier, Pierre-Luc; Chagnon, Madeleine; Derome, Nicolas; Fournier, Valérie

    2015-07-30

    While honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. Neonicotinoids have been shown to increase acetylcholinesterase (AChE) activity in honey bees at sublethal doses. High AChE levels may therefore act as a biomarker of exposure to neonicotinoids. This two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical signs of intoxication. Bumble bee colonies (Bombus impatiens) were placed in two different agricultural cropping areas: 1) control (≥ 3 km from fields planted with neonicotinoid-treated seeds) or 2) exposed (within 500 m of fields planted with neonicotinoid-treated seeds), and maintained for the duration of corn sowing. As determined by Real Time qPCR, AChE mRNA expression was initially significantly higher in bumble bees from exposed sites, then decreased throughout the planting season to reach a similar endpoint to that of bumble bees from control sites. These findings suggest that exposure to neonicotinoid seed coating particles during the planting season can alter bumble bee neuronal activity. To our knowledge, this is the first study to report in situ that bumble bees living in agricultural areas exhibit signs of neonicotinoid intoxication.

  13. Bee Stings & Their Consequences.

    ERIC Educational Resources Information Center

    Rupp, Robert M.

    1991-01-01

    Relevant information concerning bee stings is provided. Possible reactions to a bee sting and their symptoms, components of bee venom, diagnosis of hypersensitivity, and bee sting prevention and treatment are topics of discussion. The possibility of bee stings occurring during field trips and the required precautions are discussed. (KR)

  14. Bee Stings & Their Consequences.

    ERIC Educational Resources Information Center

    Rupp, Robert M.

    1991-01-01

    Relevant information concerning bee stings is provided. Possible reactions to a bee sting and their symptoms, components of bee venom, diagnosis of hypersensitivity, and bee sting prevention and treatment are topics of discussion. The possibility of bee stings occurring during field trips and the required precautions are discussed. (KR)

  15. Wing shape of four new bee fossils (Hymenoptera: Anthophila) provides insights to bee evolution.

    PubMed

    Dehon, Manuel; Michez, Denis; Nel, André; Engel, Michael S; De Meulemeester, Thibaut

    2014-01-01

    Bees (Anthophila) are one of the major groups of angiosperm-pollinating insects and accordingly are widely studied in both basic and applied research, for which it is essential to have a clear understanding of their phylogeny, and evolutionary history. Direct evidence of bee evolutionary history has been hindered by a dearth of available fossils needed to determine the timing and tempo of their diversification, as well as episodes of extinction. Here we describe four new compression fossils of bees from three different deposits (Miocene of la Cerdanya, Spain; Oligocene of Céreste, France; and Eocene of the Green River Formation, U.S.A.). We assess the similarity of the forewing shape of the new fossils with extant and fossil taxa using geometric morphometrics analyses. Predictive discriminant analyses show that three fossils share similar forewing shapes with the Apidae [one of uncertain tribal placement and perhaps near Euglossini, one definitive bumble bee (Bombini), and one digger bee (Anthophorini)], while one fossil is more similar to the Andrenidae. The corbiculate fossils are described as Euglossopteryx biesmeijeri De Meulemeester, Michez, & Engel, gen. nov. sp. nov. (type species of Euglossopteryx Dehon & Engel, n. gen.) and Bombus cerdanyensis Dehon, De Meulemeester, & Engel, sp. nov. They provide new information on the distribution and timing of particular corbiculate groups, most notably the extension into North America of possible Eocene-Oligocene cooling-induced extinctions. Protohabropoda pauli De Meulemeester & Michez, gen. nov. sp. nov. (type species of Protohabropoda Dehon & Engel, n. gen.) reinforces previous hypotheses of anthophorine evolution in terms of ecological shifts by the Oligocene from tropical to mesic or xeric habitats. Lastly, a new fossil of the Andreninae, Andrena antoinei Michez & De Meulemeester, sp. nov., further documents the presence of the today widespread genus Andrena Fabricius in the Late Oligocene of France.

  16. Wing Shape of Four New Bee Fossils (Hymenoptera: Anthophila) Provides Insights to Bee Evolution

    PubMed Central

    Dehon, Manuel; Michez, Denis; Nel, André; Engel, Michael S.; De Meulemeester, Thibaut

    2014-01-01

    Bees (Anthophila) are one of the major groups of angiosperm-pollinating insects and accordingly are widely studied in both basic and applied research, for which it is essential to have a clear understanding of their phylogeny, and evolutionary history. Direct evidence of bee evolutionary history has been hindered by a dearth of available fossils needed to determine the timing and tempo of their diversification, as well as episodes of extinction. Here we describe four new compression fossils of bees from three different deposits (Miocene of la Cerdanya, Spain; Oligocene of Céreste, France; and Eocene of the Green River Formation, U.S.A.). We assess the similarity of the forewing shape of the new fossils with extant and fossil taxa using geometric morphometrics analyses. Predictive discriminant analyses show that three fossils share similar forewing shapes with the Apidae [one of uncertain tribal placement and perhaps near Euglossini, one definitive bumble bee (Bombini), and one digger bee (Anthophorini)], while one fossil is more similar to the Andrenidae. The corbiculate fossils are described as Euglossopteryx biesmeijeri De Meulemeester, Michez, & Engel, gen. nov. sp. nov. (type species of Euglossopteryx Dehon & Engel, n. gen.) and Bombus cerdanyensis Dehon, De Meulemeester, & Engel, sp. nov. They provide new information on the distribution and timing of particular corbiculate groups, most notably the extension into North America of possible Eocene-Oligocene cooling-induced extinctions. Protohabropoda pauli De Meulemeester & Michez, gen. nov. sp. nov. (type species of Protohabropoda Dehon & Engel, n. gen.) reinforces previous hypotheses of anthophorine evolution in terms of ecological shifts by the Oligocene from tropical to mesic or xeric habitats. Lastly, a new fossil of the Andreninae, Andrena antoinei Michez & De Meulemeester, sp. nov., further documents the presence of the today widespread genus Andrena Fabricius in the Late Oligocene of France. PMID

  17. Bumble bee (Hymenoptera: Apidae) activity and pollination levels in commercial tomato greenhouses.

    PubMed

    Morandin, L A; Laverty, T M; Kevan, P G

    2001-04-01

    Commercial greenhouse studies were conducted to assess levels of pollination of tomato (Lycopersicon esculentum Mill.) flowers in relation to bumble bee (Bombus impatiens Cresson) colony activity and colony densities. For the assessment of pollination levels of tomato flowers, five categories were defined based on bruising levels caused by bumble bee pollination. Colony activity was measured as bee trips per ha/d using electric powered photodiode monitors inserted into the hive entrance. Levels of pollination were positively correlated with bee activity levels, up to a mean of approximately 400 pollen grains per stigma per day, after which greater activity did not result in further increases in daily pollination levels. Densities of colonies in the commercial greenhouses studied ranged from 7.6 to 19.8 colonies per hectare with a mean of 11.6 +/- 0.9. We found that an average activity of 2,000 bee trips per hectare per day was more than adequate to ensure sufficient pollination, and that this level of activity could be achieved with 7-15 colonies per hectare, depending on greenhouse conditions. Greenhouses requiring >15 colonies per hectare to achieve this level of pollination may be able to increase bee activity through alteration of greenhouse conditions. Across 50-m rows of tomato plants, levels of pollination decreased with increasing distance from bee colonies, suggesting that colonies should be evenly distributed throughout the greenhouses.

  18. Does Passive Sampling Accurately Reflect the Bee (Apoidea: Anthophila) Communities Pollinating Apple and Sour Cherry Orchards?

    PubMed

    Gibbs, Jason; Joshi, Neelendra K; Wilson, Julianna K; Rothwell, Nikki L; Powers, Karen; Haas, Mike; Gut, Larry; Biddinger, David J; Isaacs, Rufus

    2017-03-31

    During bloom of spring orchard crops, bees are the primary providers of pollination service. Monitoring these insects for research projects is often done by timed observations or by direct aerial netting, but there has been increasing interest in blue vane traps as an efficient passive approach to collecting bees. Over multiple spring seasons in Michigan and Pennsylvania, orchards were monitored for wild bees using timed netting from crop flowers and blue vane traps. This revealed a distinctly different community of wild bees captured using the two methods, suggesting that blue vane traps can complement but cannot replace direct aerial netting. The bee community in blue vane traps was generally composed of nonpollinating species, which can be of interest for broader biodiversity studies. In particular, blue vane traps caught Eucera atriventris (Smith), Eucera hamata (Bradley), Bombus fervidus (F.), and Agapostemon virescens (F.) that were never collected from the orchard crop flowers during the study period. Captures of bee species in nets was generally stable across the 3 yr, whereas we observed significant declines in the abundance of Lasioglossum pilosum (Smith) and Eucera spp. trapped using blue vane traps during the project, suggesting local overtrapping of reproductive individuals. We conclude that blue vane traps are a useful tool for expanding insights into bee communities within orchard crop systems, but they should be used with great caution to avoid local extirpation of these important insects.

  19. Positive and Negative Impacts of Non-Native Bee Species around the World

    PubMed Central

    Russo, Laura

    2016-01-01

    Though they are relatively understudied, non-native bees are ubiquitous and have enormous potential economic and environmental impacts. These impacts may be positive or negative, and are often unquantified. In this manuscript, I review literature on the known distribution and environmental and economic impacts of 80 species of introduced bees. The potential negative impacts of non-native bees include competition with native bees for nesting sites or floral resources, pollination of invasive weeds, co-invasion with pathogens and parasites, genetic introgression, damage to buildings, affecting the pollination of native plant species, and changing the structure of native pollination networks. The potential positive impacts of non-native bees include agricultural pollination, availability for scientific research, rescue of native species, and resilience to human-mediated disturbance and climate change. Most non-native bee species are accidentally introduced and nest in stems, twigs, and cavities in wood. In terms of number of species, the best represented families are Megachilidae and Apidae, and the best represented genus is Megachile. The best studied genera are Apis and Bombus, and most of the species in these genera were deliberately introduced for agricultural pollination. Thus, we know little about the majority of non-native bees, accidentally introduced or spreading beyond their native ranges. PMID:27916802

  20. Photoreceptor Processing Speed and Input Resistance Changes during Light Adaptation Correlate with Spectral Class in the Bumblebee, Bombus impatiens

    PubMed Central

    Skorupski, Peter; Chittka, Lars

    2011-01-01

    Colour vision depends on comparison of signals from photoreceptors with different spectral sensitivities. However, response properties of photoreceptor cells may differ in ways other than spectral tuning. In insects, for example, broadband photoreceptors, with a major sensitivity peak in the green region of the spectrum (>500 nm), drive fast visual processes, which are largely blind to chromatic signals from more narrowly-tuned photoreceptors with peak sensitivities in the blue and UV regions of the spectrum. In addition, electrophysiological properties of the photoreceptor membrane may result in differences in response dynamics of photoreceptors of similar spectral class between species, and different spectral classes within a species. We used intracellular electrophysiological techniques to investigate response dynamics of the three spectral classes of photoreceptor underlying trichromatic colour vision in the bumblebee, Bombus impatiens, and we compare these with previously published data from a related species, Bombus terrestris. In both species, we found significantly faster responses in green, compared with blue- or UV-sensitive photoreceptors, although all 3 photoreceptor types are slower in B. impatiens than in B. terrestris. Integration times for light-adapted B. impatiens photoreceptors (estimated from impulse response half-width) were 11.3±1.6 ms for green photoreceptors compared with 18.6±4.4 ms and 15.6±4.4 for blue and UV, respectively. We also measured photoreceptor input resistance in dark- and light-adapted conditions. All photoreceptors showed a decrease in input resistance during light adaptation, but this decrease was considerably larger (declining to about 22% of the dark value) in green photoreceptors, compared to blue and UV (41% and 49%, respectively). Our results suggest that the conductances associated with light adaptation are largest in green photoreceptors, contributing to their greater temporal processing speed. We suggest that the

  1. Modeling Honey Bee Populations

    PubMed Central

    Torres, David J.; Ricoy, Ulises M.; Roybal, Shanae

    2015-01-01

    Eusocial honey bee populations (Apis mellifera) employ an age stratification organization of egg, larvae, pupae, hive bees and foraging bees. Understanding the recent decline in honey bee colonies hinges on understanding the factors that impact each of these different age castes. We first perform an analysis of steady state bee populations given mortality rates within each bee caste and find that the honey bee colony is highly susceptible to hive and pupae mortality rates. Subsequently, we study transient bee population dynamics by building upon the modeling foundation established by Schmickl and Crailsheim and Khoury et al. Our transient model based on differential equations accounts for the effects of pheromones in slowing the maturation of hive bees to foraging bees, the increased mortality of larvae in the absence of sufficient hive bees, and the effects of food scarcity. We also conduct sensitivity studies and show the effects of parameter variations on the colony population. PMID:26148010

  2. Modeling Honey Bee Populations.

    PubMed

    Torres, David J; Ricoy, Ulises M; Roybal, Shanae

    2015-01-01

    Eusocial honey bee populations (Apis mellifera) employ an age stratification organization of egg, larvae, pupae, hive bees and foraging bees. Understanding the recent decline in honey bee colonies hinges on understanding the factors that impact each of these different age castes. We first perform an analysis of steady state bee populations given mortality rates within each bee caste and find that the honey bee colony is highly susceptible to hive and pupae mortality rates. Subsequently, we study transient bee population dynamics by building upon the modeling foundation established by Schmickl and Crailsheim and Khoury et al. Our transient model based on differential equations accounts for the effects of pheromones in slowing the maturation of hive bees to foraging bees, the increased mortality of larvae in the absence of sufficient hive bees, and the effects of food scarcity. We also conduct sensitivity studies and show the effects of parameter variations on the colony population.

  3. CORRELATION OF SOUND GENERATION AND METABOLIC HEAT FLUX IN THE BUMBLEBEE BOMBUS LAPIDARIUS

    PubMed

    Schultze-Motel; Lamprecht

    1994-02-01

    Flying insects produce extreme amounts of heat as a by-product during the contractions of their thoracic flight muscles (Heinrich, 1989). Before flight, metabolic heat may serve to warm up the thoracic muscles until the minimum lift-off temperature is reached (Heinrich, 1974b; Stone and Willmer, 1989; Esch and Goller, 1991). Social bees and wasps are also able to use the heat produced in their flight muscles for brood incubation and for active regulation of nest temperatures (Heinrich, 1974a; Seeley and Heinrich, 1981; Schultze-Motel, 1991). In this study, we report simultaneous measurements of heat flux and sound generation by wing buzzing in individual bumblebee workers (Bombus lapidarius L.). Bumblebees used in the experiments were taken from colonies in observation nest boxes (Schultze-Motel, 1991) and placed into the cylindrical 100 ml stainless-steel vessel of a Calvet-type microcalorimeter (MS 70, Setaram, Lyon; Wadso, 1987). A small microphone had been installed below the screw cap of the calorimeter vessel. The sensitivity of the calorimeter under these conditions was 41.7 mV W-1. Both the calorimeter and the microphone signals were amplified and recorded on a dual-channel chart recorder. In 32 out of a total of 36 measurements, the bumblebees showed prolonged periods of sound generation, most frequently at the beginning of experiments. We assume that the sound was not produced in an alarm reaction, but by flight movements of the wings when the animals attempted to lift off inside the calorimeter vessel. The buzzing sounds produced by bumblebees are caused by oscillations of the flight muscles inside the metathorax (Schneider, 1975). Previous endoscopic observations of bumblebees sitting on the bottom of our calorimeter vessel had shown that there was a one-to-one correlation between episodes of wing movements and sound production. The microphone recordings thus allowed an easy way of measuring locomotor activity inside the calorimeter. The simultaneous

  4. Comparative studies of pollen and fluorescent dye transport by bumble bees visiting Erythronium grandiflorum.

    PubMed

    Thomson, James D; Price, Mary V; Waser, Nickolas M; Stratton, Donald A

    1986-07-01

    In the Colorado Rocky Mountains the glacier lily Erythronium grandiflorum exhibits a striking dimorphism in pollen color and is commonly pollinated by the bumble bee Bombus occidentalis. We induced bees to visit sequences of flowers in a flight cage, and compared dispersal of distinctively-colored pollen and fluorescent pigment ("dye") that the bee had picked up at a single donor flower. Nonparametric and parametric analyses showed that dispersal properties of pollen and dye differed; consistently less pollen was deposited and it was carried consistently shorter distances than dye. Dye thus does not provide an accurate means of assessing exacty where or how far pollen travels in this plant-pollinator system. On the other hand, both pollen and dye responded similarly to several experimental manipulations of donor and recipient flowers. Hence dye may well be of value for a qualitative investigation of how floral traits influence pollen dispersal.

  5. First detection of the larval chalkbrood disease pathogen Ascosphaera apis (Ascomycota: Eurotiomycetes: Ascosphaerales) in adult bumble bees.

    PubMed

    Maxfield-Taylor, Sarah A; Mujic, Alija B; Rao, Sujaya

    2015-01-01

    Fungi in the genus Ascosphaera (Ascomycota: Eurotiomycetes: Ascosphaerales) cause chalkbrood disease in larvae of bees. Here, we report the first-ever detection of the fungus in adult bumble bees that were raised in captivity for studies on colony development. Wild queens of Bombus griseocollis, B. nevadensis and B. vosnesenskii were collected and maintained for establishment of nests. Queens that died during rearing or that did not lay eggs within one month of capture were dissected, and tissues were examined microscopically for the presence of pathogens. Filamentous fungi that were detected were plated on artificial media containing broad spectrum antibiotics for isolation and identification. Based on morphological characters, the fungus was identified as Ascosphaera apis (Maasen ex Claussen) Olive and Spiltoir, a species that has been reported earlier only from larvae of the European honey bee, Apis mellifera, the Asian honey bee, Apis cerana, and the carpenter bee Xylocopa californica arizonensis. The identity of the fungus was confirmed using molecular markers and phylogenetic analysis. Ascosphaera apis was detected in queens of all three bumble bee species examined. Of 150 queens dissected, 12 (8%) contained vegetative and reproductive stages of the fungus. Both fungal stages were also detected in two workers collected from colonies with Ascosphaera-infected B. nevadensis queens. In this study, wild bees could have been infected prior to capture for rearing, or, the A. apis infection could have originated via contaminated European honey bee pollen fed to the bumble bees in captivity. Thus, the discovery of A. apis in adult bumble bees in the current study has important implications for commercial production of bumble bee colonies and highlights potential risks to native bees via pathogen spillover from infected bees and infected pollen.

  6. First Detection of the Larval Chalkbrood Disease Pathogen Ascosphaera apis (Ascomycota: Eurotiomycetes: Ascosphaerales) in Adult Bumble Bees

    PubMed Central

    Maxfield-Taylor, Sarah A.; Mujic, Alija B.; Rao, Sujaya

    2015-01-01

    Fungi in the genus Ascosphaera (Ascomycota: Eurotiomycetes: Ascosphaerales) cause chalkbrood disease in larvae of bees. Here, we report the first-ever detection of the fungus in adult bumble bees that were raised in captivity for studies on colony development. Wild queens of Bombus griseocollis, B. nevadensis and B. vosnesenskii were collected and maintained for establishment of nests. Queens that died during rearing or that did not lay eggs within one month of capture were dissected, and tissues were examined microscopically for the presence of pathogens. Filamentous fungi that were detected were plated on artificial media containing broad spectrum antibiotics for isolation and identification. Based on morphological characters, the fungus was identified as Ascosphaera apis (Maasen ex Claussen) Olive and Spiltoir, a species that has been reported earlier only from larvae of the European honey bee, Apis mellifera, the Asian honey bee, Apis cerana, and the carpenter bee Xylocopa californica arizonensis. The identity of the fungus was confirmed using molecular markers and phylogenetic analysis. Ascosphaera apis was detected in queens of all three bumble bee species examined. Of 150 queens dissected, 12 (8%) contained vegetative and reproductive stages of the fungus. Both fungal stages were also detected in two workers collected from colonies with Ascosphaera-infected B. nevadensis queens. In this study, wild bees could have been infected prior to capture for rearing, or, the A. apis infection could have originated via contaminated European honey bee pollen fed to the bumble bees in captivity. Thus, the discovery of A. apis in adult bumble bees in the current study has important implications for commercial production of bumble bee colonies and highlights potential risks to native bees via pathogen spillover from infected bees and infected pollen. PMID:25885679

  7. Transcript expression bias of phosphatidylethanolamine binding protein gene in bumblebee, Bombus lantschouensis (Hymenoptera: Apidae).

    PubMed

    Dong, Jie; Han, Lei; Wang, Ye; Huang, Jiaxing; Wu, Jie

    2017-09-05

    The phosphatidylethanolamine-binding protein (PEBP) family is a highly conserved group of proteins found in a wide range of organism. It plays an important role in innate immunity of insects. Little is known on the expression characteristic and function of PEBP in bees. In the current study, we cloned the pebp gene and investigated its expression profiles at different developmental stages and reproductive status from bumblebee, Bombus lantschouensis (Vogt), which is one of the most abundant pollinators for wild plants and crops in Northern China. Two transcripts (PEBPX1 and PEBPX2) of the pebp gene were cloned for the first time. The transcript PEBPX2 lacked a signal peptide sequence compared to PEBPX1. The full-length cDNA of these two PEBP transcripts is 1005bp and 915bp, with an open reading frame of 627bp and 549bp, respectively. Transcript PEBPX2 was one order of magnitude more expressed than transcript PEBPX1 at most of the developmental stages and different reproductive status (egg-laying versus non- egg-laying females). Both of the PEBP transcripts were highly expressed in brown-eyed with light and dark pigmented cuticle pupae stages. Quantitative PCR and Western Blot demonstrated that PEBP was significantly up-regulated in egg-laying females. In summary, we suggest that levels of these two PEBPs could be related to the regulation of reproduction in bumblebees. In addition, both transcripts likely play an important role in the metamorphosis developmental stage of bumblebee pupae. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Comparison of buckwheat, red clover, and purple tansy as potential surrogate plants for use in semi-field pesticide risk assessments with Bombus impatiens

    PubMed Central

    Cutler, G. Christopher; Frewin, Andrew J.; Scott-Dupree, Cynthia D.

    2016-01-01

    Background. Bumble bees (Bombus spp.) are important wild and managed pollinators. There is increased interest in incorporating data on bumble bees into risk assessments for pesticides, but standardized methods for assessing hazards of pesticides in semi-field and field settings have not yet been established for bumble bees. During semi-field studies, colonies are caged with pesticide-treated flowering surrogate plants, which must be attractive to foragers to ensure colony exposure to the test compound, and must produce an ample nectar and pollen to sustain colonies during testing. However, it is not known which plant(s) are suitable for use in semi-field studies with bumble bees. Materials and Methods. We compared B. impatiens foraging activity and colony development on small plots of flowering buckwheat (Fagopyrum esculentum, var. common), red clover (Trifolium pratense), and purple tansy (Phacelia tanacetifolia) under semi-field conditions to assess their suitability as surrogate plants for pesticide risk assessment studies with bumble bees. We also compared the growth characteristics and input requirements of each plant type. Results. All three plant types generally established and grew well. Red clover and purple tansy experienced significant weed pressure and/or insect pest damage. In contrast, pest pressure was extremely low in buckwheat. Overall, B. impatiens foraging activity was significantly greater on buckwheat plots than red clover or purple tansy, but plant type had no effect on number of individuals produced per colony or colony weight. Discussion. Because of the consistently high foraging activity and successful colony development observed on buckwheat plots, combined with its favourable growth characteristics and low maintenance requirements, we recommend buckwheat as a surrogate plant for use in semi-field pesticide toxicity assessments with B. impatiens. PMID:27478712

  9. Unusual fatty acids in the fat body of the early nesting bumblebee, Bombus pratorum.

    PubMed

    Cvacka, Josef; Kofronová, Edita; Vasícková, Sona; Stránský, Karel; Jiros, Pavel; Hovorka, Oldrich; Kindl, Jirí; Valterová, Irena

    2008-05-01

    Unusual fatty acids with 24, 26, and 28 carbon atoms were found in triacylglycerols (TAGs) isolated from fat body tissue of bumblebee Bombus pratorum. The most abundant one was (Z,Z)-9,19-hexacosadienoic acid. Its structure was determined by mass spectrometry after derivatization with dimethyl disulfide and by infrared spectroscopy. ECL (equivalent chain length) values of its methyl ester were determined on both DB-1 and DB-WAX capillary columns. (Z,Z)-9,19-Hexacosadienoic acid is quite rare in nature. So far it has been identified only in marine sponges, and this work is the first evidence of its occurrence in a terrestrial organism. HPLC/MS analysis of the bumblebee TAGs showed that (Z,Z)-9,19-hexacosadienoic acid is present in one third of all TAG molecular species. As it was found in all sn-TAG positions, it is likely that (Z,Z)-9,19-hexacosadienoic acid is transported to tissues. Interestingly, labial gland secretion of B. pratorum was found to contain (Z,Z)-7,17-pentacosadiene, a hydrocarbon with markedly similar double bond positions and geometry. Possible biosynthetic relationships between these two compounds are discussed.

  10. Influence of honey bee, Apis mellifera, hives and field size on foraging activity of native bee species in pumpkin fields.

    PubMed

    Artz, Derek R; Hsu, Cynthia L; Nault, Brian A

    2011-10-01

    The purpose of this study was to identify bee species active in pumpkin fields in New York and to estimate their potential as pollinators by examining their foraging activity. In addition, we examined whether foraging activity was affected by either the addition of hives of the honey bee, Apis mellifera L., or by field size. Thirty-five pumpkin (Cucurbita spp.) fields ranging from 0.6 to 26.3 ha, 12 supplemented with A. mellifera hives and 23 not supplemented, were sampled during peak flowering over three successive weeks in 2008 and 2009. Flowers from 300 plants per field were visually sampled for bees on each sampling date. A. mellifera, Bombus impatiens Cresson, and Peponapis pruinosa (Say) accounted for 99% of all bee visits to flowers. A. mellifera and B. impatiens visited significantly more pistillate flowers than would be expected by chance, whereas P. pruinosa showed no preference for visiting pistillate flowers. There were significantly more A. mellifera visits per flower in fields supplemented with A. mellifera hives than in fields not supplemented, but there were significantly fewer P. pruinosa visits in supplemented fields. The number of B. impatiens visits was not affected by supplementation, but was affected by number of flowers per field. A. mellifera and P. pruinosa visits were not affected by field size, but B. impatiens visited fewer flowers as field size increased in fields that were not supplemented with A. mellifera hives. Declining A. mellifera populations may increase the relative importance of B. impatiens in pollinating pumpkins in New York.

  11. A survey of bees (hymenoptera: Apoidea) of the Indiana dunes and Northwest Indiana, USA

    USGS Publications Warehouse

    Grundel, R.; Jean, R.P.; Frohnapple, K.J.; Gibbs, J.; Glowacki, G.A.; Pavlovic, N.B.

    2011-01-01

    The Indiana Dunes, and nearby natural areas in northwest Indiana, are floristically rich Midwest U.S. locales with many habitat types. We surveyed bees along a habitat gradient ranging from grasslands to forests in these locales, collecting at least 175 bee species along this gradient plus 29 additional species in other nearby habitats. About 25% of all species were from the genus Lasioglossum and 12% of the species were associated with sandy soils. Several bumblebee (Bombus) species of conservation concern that should occur in this region were not collected during our surveys. Similarity of the northwest Indiana bee fauna to other published U.S. faunas decreased about 1.3% per 100 km distance from northwest Indiana. Thirty percent of bees netted from flowers were males. Males and females differed significantly in their frequency of occurrence on different plant species. For bees collected in bowl traps, the percentage captured in fluorescent yellow traps declined and in fluorescent blue traps increased from spring to late summer. Capture rates for different bee genera varied temporally, with about a quarter of the genera being captured most frequently in late spring and a quarter in late summer. Capture rates for most genera were higher in more open than in more closed canopy habitats. The maximum number of plant species on which a single bee species was captured plateaued at 24, on average. Forty-nine percent of bee species known to occur in Indiana were found at these northwest Indiana sites. Having this relatively high proportion of the total Indiana bee fauna is consistent with Indiana Dunes existing at a biogeographic crossroads where grassland and forest biomes meet in a landscape whose climate and soils are affected by proximity to Lake Michigan. The resulting habitat, plant, edaphic, and climatic diversity likely produces the diverse bee community documented.

  12. The bee microbiome: Impact on bee health and model for evolution and ecology of host-microbe interactions

    USGS Publications Warehouse

    Engel, Philipp; Kwong, Waldan K.; McFrederick, Quinn; Anderson, Kirk E.; Barribeau, Seth Michael; Chandler, James Angus; Cornman, Robert S.; Dainat, Jacques; de Miranda, Joachim R.; Doublet, Vincent; Emery, Olivier; Evans, Jay D.; Farinelli, Laurent; Flenniken, Michelle L.; Granberg, Fredrik; Grasis, Juris A.; Gauthier, Laurent; Hayer, Juliette; Koch, Hauke; Kocher, Sarah; Martinson, Vincent G.; Moran, Nancy; Munoz-Torres, Monica; Newton, Irene; Paxton, Robert J.; Powell, Eli; Sadd, Ben M.; Schmid-Hempel, Paul; Schmid-Hempel, Regula; Song, Se Jin; Schwarz, Ryan S.; vanEngelsdorp, Dennis; Dainat, Benjamin

    2016-01-01

    As pollinators, bees are cornerstones for terrestrial ecosystem stability and key components in agricultural productivity. All animals, including bees, are associated with a diverse community of microbes, commonly referred to as the microbiome. The bee microbiome is likely to be a crucial factor affecting host health. However, with the exception of a few pathogens, the impacts of most members of the bee microbiome on host health are poorly understood. Further, the evolutionary and ecological forces that shape and change the microbiome are unclear. Here, we discuss recent progress in our understanding of the bee microbiome, and we present challenges associated with its investigation. We conclude that global coordination of research efforts is needed to fully understand the complex and highly dynamic nature of the interplay between the bee microbiome, its host, and the environment. High-throughput sequencing technologies are ideal for exploring complex biological systems, including host-microbe interactions. To maximize their value and to improve assessment of the factors affecting bee health, sequence data should be archived, curated, and analyzed in ways that promote the synthesis of different studies. To this end, the BeeBiome consortium aims to develop an online database which would provide reference sequences, archive metadata, and host analytical resources. The goal would be to support applied and fundamental research on bees and their associated microbes and to provide a collaborative framework for sharing primary data from different research programs, thus furthering our understanding of the bee microbiome and its impact on pollinator health.

  13. The Bee Microbiome: Impact on Bee Health and Model for Evolution and Ecology of Host-Microbe Interactions

    PubMed Central

    Kwong, Waldan K.; McFrederick, Quinn; Anderson, Kirk E.; Barribeau, Seth Michael; Chandler, James Angus; Cornman, R. Scott; Dainat, Jacques; Doublet, Vincent; Emery, Olivier; Evans, Jay D.; Farinelli, Laurent; Flenniken, Michelle L.; Granberg, Fredrik; Grasis, Juris A.; Gauthier, Laurent; Hayer, Juliette; Koch, Hauke; Kocher, Sarah; Martinson, Vincent G.; Moran, Nancy; Munoz-Torres, Monica; Newton, Irene; Paxton, Robert J.; Powell, Eli; Sadd, Ben M.; Schmid-Hempel, Paul; Schmid-Hempel, Regula; Schwarz, Ryan S.; vanEngelsdorp, Dennis

    2016-01-01

    ABSTRACT As pollinators, bees are cornerstones for terrestrial ecosystem stability and key components in agricultural productivity. All animals, including bees, are associated with a diverse community of microbes, commonly referred to as the microbiome. The bee microbiome is likely to be a crucial factor affecting host health. However, with the exception of a few pathogens, the impacts of most members of the bee microbiome on host health are poorly understood. Further, the evolutionary and ecological forces that shape and change the microbiome are unclear. Here, we discuss recent progress in our understanding of the bee microbiome, and we present challenges associated with its investigation. We conclude that global coordination of research efforts is needed to fully understand the complex and highly dynamic nature of the interplay between the bee microbiome, its host, and the environment. High-throughput sequencing technologies are ideal for exploring complex biological systems, including host-microbe interactions. To maximize their value and to improve assessment of the factors affecting bee health, sequence data should be archived, curated, and analyzed in ways that promote the synthesis of different studies. To this end, the BeeBiome consortium aims to develop an online database which would provide reference sequences, archive metadata, and host analytical resources. The goal would be to support applied and fundamental research on bees and their associated microbes and to provide a collaborative framework for sharing primary data from different research programs, thus furthering our understanding of the bee microbiome and its impact on pollinator health. PMID:27118586

  14. Visitation by wild and managed bees (Hymenoptera: Apoidea) to eastern U.S. native plants for use in conservation programs.

    PubMed

    Tuell, Julianna K; Fiedler, Anna K; Landis, Douglas; Isaacs, Rufus

    2008-06-01

    Addition of floral resources to agricultural field margins has been shown to increase abundance of beneficial insects in crop fields, but most plants recommended for this use are non-native annuals. Native perennial plants with different bloom periods can provide floral resources for bees throughout the growing season for use in pollinator conservation projects. To identify the most suitable plants for this use, we examined the relative attractiveness to wild and managed bees of 43 eastern U.S. native perennial plants, grown in a common garden setting. Floral characteristics were evaluated for their ability to predict bee abundance and taxa richness. Of the wild bees collected, the most common species (62%) was Bombus impatiens Cresson. Five other wild bee species were present between 3 and 6% of the total: Lasioglossum admirandum (Sandhouse), Hylaeus affinis (Smith), Agapostemon virescens (F.), Halictus ligatus Say, and Ceratina calcarata/dupla Robertson/Say. The remaining wild bee species were present at <2% of the total. Abundance of honey bees (Apis mellifera L.) was nearly identical to that of B. impatiens. All plant species were visited at least once by wild bees; 9 were highly attractive, and 20 were moderately attractive. Honey bees visited 24 of the 43 plant species at least once. Floral area was the only measured factor accounting for variation in abundance and richness of wild bees but did not explain variation in honey bee abundance. Results of this study can be used to guide selection of flowering plants to provide season-long forage for conservation of wild bees.

  15. Context-dependent medicinal effects of anabasine and infection-dependent toxicity in bumble bees

    PubMed Central

    Hogeboom, Alison; Kaye, Alexander J.; Andicoechea, Jonathan; Connon, Sara June; Weston, Ian; Skyrm, Kimberly; Irwin, Rebecca E.; Adler, Lynn S.

    2017-01-01

    Background Floral phytochemicals are ubiquitous in nature, and can function both as antimicrobials and as insecticides. Although many phytochemicals act as toxins and deterrents to consumers, the same chemicals may counteract disease and be preferred by infected individuals. The roles of nectar and pollen phytochemicals in pollinator ecology and conservation are complex, with evidence for both toxicity and medicinal effects against parasites. However, it remains unclear how consistent the effects of phytochemicals are across different parasite lineages and environmental conditions, and whether pollinators actively self-medicate with these compounds when infected. Approach Here, we test effects of the nectar alkaloid anabasine, found in Nicotiana, on infection intensity, dietary preference, and survival and performance of bumble bees (Bombus impatiens). We examined variation in the effects of anabasine on infection with different lineages of the intestinal parasite Crithidia under pollen-fed and pollen-starved conditions. Results We found that anabasine did not reduce infection intensity in individual bees infected with any of four Crithidia lineages that were tested in parallel, nor did anabasine reduce infection intensity in microcolonies of queenless workers. In addition, neither anabasine nor its isomer, nicotine, was preferred by infected bees in choice experiments, and infected bees consumed less anabasine than did uninfected bees under no-choice conditions. Furthermore, anabasine exacerbated the negative effects of infection on bee survival and microcolony performance. Anabasine reduced infection in only one experiment, in which bees were deprived of pollen and post-pupal contact with nestmates. In this experiment, anabasine had antiparasitic effects in bees from only two of four colonies, and infected bees exhibited reduced—rather than increased—phytochemical consumption relative to uninfected bees. Conclusions Variation in the effect of anabasine on

  16. Context-dependent medicinal effects of anabasine and infection-dependent toxicity in bumble bees.

    PubMed

    Palmer-Young, Evan C; Hogeboom, Alison; Kaye, Alexander J; Donnelly, Dash; Andicoechea, Jonathan; Connon, Sara June; Weston, Ian; Skyrm, Kimberly; Irwin, Rebecca E; Adler, Lynn S

    2017-01-01

    Floral phytochemicals are ubiquitous in nature, and can function both as antimicrobials and as insecticides. Although many phytochemicals act as toxins and deterrents to consumers, the same chemicals may counteract disease and be preferred by infected individuals. The roles of nectar and pollen phytochemicals in pollinator ecology and conservation are complex, with evidence for both toxicity and medicinal effects against parasites. However, it remains unclear how consistent the effects of phytochemicals are across different parasite lineages and environmental conditions, and whether pollinators actively self-medicate with these compounds when infected. Here, we test effects of the nectar alkaloid anabasine, found in Nicotiana, on infection intensity, dietary preference, and survival and performance of bumble bees (Bombus impatiens). We examined variation in the effects of anabasine on infection with different lineages of the intestinal parasite Crithidia under pollen-fed and pollen-starved conditions. We found that anabasine did not reduce infection intensity in individual bees infected with any of four Crithidia lineages that were tested in parallel, nor did anabasine reduce infection intensity in microcolonies of queenless workers. In addition, neither anabasine nor its isomer, nicotine, was preferred by infected bees in choice experiments, and infected bees consumed less anabasine than did uninfected bees under no-choice conditions. Furthermore, anabasine exacerbated the negative effects of infection on bee survival and microcolony performance. Anabasine reduced infection in only one experiment, in which bees were deprived of pollen and post-pupal contact with nestmates. In this experiment, anabasine had antiparasitic effects in bees from only two of four colonies, and infected bees exhibited reduced-rather than increased-phytochemical consumption relative to uninfected bees. Variation in the effect of anabasine on infection suggests potential modulation of

  17. Behavioural ecology: bees associate warmth with floral colour.

    PubMed

    Dyer, Adrian G; Whitney, Heather M; Arnold, Sarah E J; Glover, Beverley J; Chittka, Lars

    2006-08-03

    Floral colour signals are used by pollinators as predictors of nutritional rewards, such as nectar. But as insect pollinators often need to invest energy to maintain their body temperature above the ambient temperature, floral heat might also be perceived as a reward. Here we show that bumblebees (Bombus terrestris) prefer to visit warmer flowers and that they can learn to use colour to predict floral temperature before landing. In what could be a widespread floral adaptation, plants may modulate their temperature to encourage pollinators to visit.

  18. Native Bee Diversity and Pollen Foraging Specificity in Cultivated Highbush Blueberry (Ericaceae: Vaccinium corymbosum) in Rhode Island.

    PubMed

    Scott, Zachary; Ginsberg, Howard S; Alm, Steven R

    2016-12-01

    We identified 41 species of native bees from a total of 1,083 specimens collected at cultivated highbush blueberry plantings throughout Rhode Island in 2014 and 2015. Andrena spp., Bombus spp., and Xylocopa virginica (L.) were collected most often. Bombus griseocollis (DeGeer), B. impatiens Cresson, B. bimaculatus Cresson, B. perplexus Cresson, and Andrena vicina Smith collected the largest mean numbers of blueberry pollen tetrads. The largest mean percent blueberry pollen loads were carried by the miner bees Andrena bradleyi Viereck (91%), A. carolina Viereck (90%), and Colletes validus Cresson (87%). The largest mean total pollen grain loads were carried by B. griseocollis (549,844), B. impatiens (389,558), X. virginica (233,500), and B. bimaculatus (193,132). Xylocopa virginica was the fourth and fifth most commonly collected bee species in 2014 and 2015, respectively. They exhibit nectar robbing and females carried relatively low blueberry pollen loads (mean 33%). Overall, we found 10 species of bees to be the primary pollinators of blueberries in Rhode Island. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Native bee diversity and pollen foraging specificity in cultivated highbush blueberry (Ericaceae: Vaccinium corymbosum) in Rhode Island

    USGS Publications Warehouse

    Scott, Zachary; Ginsberg, Howard; Alm, Steven R.

    2016-01-01

    We identified 41 species of native bees from a total of 1,083 specimens collected at cultivated highbush blueberry plantings throughout Rhode Island in 2014 and 2015. Andrena spp., Bombus spp., and Xylocopa virginica (L.) were collected most often. Bombus griseocollis (DeGeer), B. impatiens Cresson, B. bimaculatus Cresson, B. perplexus Cresson, and Andrena vicina Smith collected the largest mean numbers of blueberry pollen tetrads. The largest mean percent blueberry pollen loads were carried by the miner bees Andrena bradleyi Viereck (91%), A. carolina Viereck (90%), and Colletes validus Cresson (87%). The largest mean total pollen grain loads were carried by B. griseocollis (549,844), B. impatiens (389,558), X. virginica (233,500), and B. bimaculatus (193,132). Xylocopa virginica was the fourth and fifth most commonly collected bee species in 2014 and 2015, respectively. They exhibit nectar robbing and females carried relatively low blueberry pollen loads (mean 33%). Overall, we found 10 species of bees to be the primary pollinators of blueberries in Rhode Island.

  20. Native Bee Diversity and Pollen Foraging Specificity in Cultivated Highbush Blueberry (Ericaceae: Vaccinium corymbosum) in Rhode Island.

    PubMed

    Scott, Zachary; Ginsberg, Howard S; Alm, Steven R

    2016-10-15

    We identified 41 species of native bees from a total of 1,083 specimens collected at cultivated highbush blueberry plantings throughout Rhode Island in 2014 and 2015. Andrena spp., Bombus spp., and Xylocopa virginica (L.) were collected most often. Bombus griseocollis (DeGeer), B. impatiens Cresson, B. bimaculatus Cresson, B. perplexus Cresson, and Andrena vicina Smith collected the largest mean numbers of blueberry pollen tetrads. The largest mean percent blueberry pollen loads were carried by the miner bees Andrena bradleyi Viereck (91%), A. carolina Viereck (90%), and Colletes validus Cresson (87%). The largest mean total pollen grain loads were carried by B. griseocollis (549,844), B. impatiens (389,558), X. virginica (233,500), and B. bimaculatus (193,132). Xylocopa virginica was the fourth and fifth most commonly collected bee species in 2014 and 2015, respectively. They exhibit nectar robbing and females carried relatively low blueberry pollen loads (mean 33%). Overall, we found 10 species of bees to be the primary pollinators of blueberries in Rhode Island.

  1. Colony-level variation in pollen collection and foraging preferences among wild-caught bumble bees (Hymenoptera: Apidae).

    PubMed

    Saifuddin, Mustafa; Jha, Shalene

    2014-04-01

    Given that many pollinators have exhibited dramatic declines related to habitat destruction, an improved understanding of pollinator resource collection across human-altered landscapes is essential to conservation efforts. Despite the importance of bumble bees (Bombus spp.) as global pollinators, little is known regarding how pollen collection patterns vary between individuals, colonies, and landscapes. In this study, Vosnesensky bumble bees (Bombus vosnesenskii Radoszkowski) were collected from a range of human-altered and natural landscapes in northern California. Extensive vegetation surveys and Geographic Information System (GIS)-based habitat classifications were conducted at each site, bees were genotyped to identify colony mates, and pollen loads were examined to identify visited plants. In contrast to predictions based on strong competitive interactions, pollen load composition was significantly more similar for bees captured in a shared study region compared with bees throughout the research area but was not significantly more similar for colony mates. Preference analyses revealed that pollen loads were not composed of the most abundant plant species per study region. The majority of ranked pollen preference lists were significantly correlated for pairwise comparisons of colony mates and individuals within a study region, whereas the majority of pairwise comparisons of ranked pollen preference lists between individuals located at separate study regions were uncorrelated. Results suggest that pollen load composition and foraging preferences are similar for bees throughout a shared landscape regardless of colony membership. The importance of native plant species in pollen collection is illustrated through preference analyses, and we suggest prioritization of specific rare native plant species for enhanced bumble bee pollen collection.

  2. Non-Euglossine bees also function as pollinators of Sinningia species (Gesneriaceae) in southeastern brazil.

    PubMed

    SanMartin-Gajardo, I; Sazima, M

    2004-07-01

    Pollination by male and female Euglossini bees, euglossophily, was suggested for a number of neotropical Gesneriaceae species. Information on bee species other than Euglossini as pollinators of neotropical members of this family is limited, and in the tribe Sinningieae data about bee pollination are still lacking. Here, we report on floral biology and bee pollination of four Sinningia species: S. schiffneri, S. eumorpha, S. villosa, and Sinningia "canastrensis". The flower features, such as corolla size, shape, and colour, are very different among the four species, but all conform to the melittophilous syndrome. The average nectar volume and sugar amount is low in S. schiffneri, S. eumorpha, and Sinningia "canastrensis", when compared to that of S. villosa, but low nectar amounts is a general feature of Sinningia species. The main pollinators of the four species are: small Tapinotaspidini (Trigonopedia ferruginea) of S. schiffneri, large Bombini (Bombus morio) and large Centridini (Epicharis morio) of S. eumorpha, large Euglossini (Eulaema cingulata and Eufriesea surinamensis) of S. villosa, and large Euglossini (Eufriesea violascens) and Megachilini (Megachile sp.) of Sinningia "canastrensis". Out of the four species, only S. villosa is exclusively Euglossini-pollinated. The marked differences in flower features and nectar production of these Sinningia species may reflect their pollination by distinct groups of bees. These results strengthen the idea of multiple origins for the pollination systems involving bees within this genus, which is highly supported by molecular phylogenetic analyses. Copyright Georg Thieme Verlag KG Stuttgart

  3. Effect of Three Entomopathogenic Fungi on Three Species of Stingless Bees (Hymenoptera: Apidae) Under Laboratory Conditions.

    PubMed

    Toledo-Hernández, R A; Ruíz-Toledo, J; Toledo, J; Sánchez, D

    2016-05-04

    Development of alternative strategies for pest control with reduced effect on beneficial organisms is a priority given the increasing global loss of biodiversity. Biological control with entomopathogenic fungi arises as a viable option to control insect pests. However, few studies have focused on the consequences of using these organisms on pollinators other than the honey bee (Apis mellifera L.) or bumble bees (Bombus spp). We evaluated the pathogenicity of commercial formulations of three widely used entomopathogenic fungi, Metarhizium anisopliae (Metschnikoff) Sorokin, Beauveria bassiana Vuillemin, and Isaria fumosorosea (Wize), to three species of stingless bees: Tetragonisca angustula Latreille, Scaptotrigona mexicana Guérin-Meneville, and Melipona beecheii Bennett. Bioassays consisted of exposing groups of bees to the recommended field concentration of each fungus using a microspray tower under laboratory conditions. Susceptibility to fungi varied greatly among species. Isaria fumosorosea (strain Ifu-lu 01) and the two formulations of B. bassiana (Bea-TNK and BotanicGard) caused <30.3% mortality in all bee species. Metarhizium anisopliae (Meta-TNK and strain Ma-lu 01) was highly active against T. angustula (94.2% mortality) and moderately active against M. beecheii (53.0% mortality) and S. mexicana (38.9% mortality). Though our laboratory-derived results suggest a moderate to high impact of these entomopathogenic fungi on stingless bees, further field studies are required to support this finding.

  4. Molecular characterization of iron binding proteins, transferrin and ferritin heavy chain subunit, from the bumblebee Bombus ignitus.

    PubMed

    Wang, Dong; Kim, Bo Yeon; Lee, Kwang Sik; Yoon, Hyung Joo; Cui, Zheng; Lu, Wei; Jia, Jing Ming; Kim, Doh Hoon; Sohn, Hung Dae; Jin, Byung Rae

    2009-01-01

    Transferrin and ferritin are iron-binding proteins involved in transport and storage of iron as part of iron metabolism. Here, we describe the cDNA cloning and characterization of transferrin (Bi-Tf) and the ferritin heavy chain subunit (Bi-FerHCH), from the bumblebee Bombus ignitus. Bi-Tf cDNA spans 2340 bp and encodes a protein of 706 amino acids and Bi-FerHCH cDNA spans 1393 bp and encodes a protein of 217 amino acids. Comparative analysis revealed that Bi-Tf appears to have residues comprising iron-binding sites in the N-terminal lobe, and Bi-FerHCH contains a 5'UTR iron-responsive element and seven conserved amino acid residues associated with a ferroxidase center. The Bi-Tf and Bi-FerHCH cDNAs were expressed as 79 kDa and 27 kDa polypeptides, respectively, in baculovirus-infected insect Sf9 cells. Northern blot analysis revealed that Bi-Tf exhibits fat body-specific expression and Bi-FerHCH shows ubiquitous expression. The expression profiles of the Bi-Tf and Bi-FerHCH in the fat body of B. ignitus worker bees revealed that Bi-Tf and Bi-FerHCH are differentially induced in a time-dependent manner in a single insect by wounding, bacterial challenge, and iron overload.

  5. Bee-Wild about Pollinators!

    ERIC Educational Resources Information Center

    Johnson, Bonnie; Kil, Jenny; Evans, Elaine; Koomen, Michele Hollingsworth

    2014-01-01

    With their sunny stripes and fuzzy bodies, bees are beloved--but unfortunately, they are in trouble. Bee decline, of both wild bees as well as managed bees like honey bees, has been in the news for the last several years. Habitat loss, diseases, pests, and pesticides have made it difficult for bees to survive in many parts of our world (Walsh…

  6. Bee-Wild about Pollinators!

    ERIC Educational Resources Information Center

    Johnson, Bonnie; Kil, Jenny; Evans, Elaine; Koomen, Michele Hollingsworth

    2014-01-01

    With their sunny stripes and fuzzy bodies, bees are beloved--but unfortunately, they are in trouble. Bee decline, of both wild bees as well as managed bees like honey bees, has been in the news for the last several years. Habitat loss, diseases, pests, and pesticides have made it difficult for bees to survive in many parts of our world (Walsh…

  7. Assessing Insecticide Hazard to Bumble Bees Foraging on Flowering Weeds in Treated Lawns

    PubMed Central

    Larson, Jonathan L.; Redmond, Carl T.; Potter, Daniel A.

    2013-01-01

    Maintaining bee-friendly habitats in cities and suburbs can help conserve the vital pollination services of declining bee populations. Despite label precautions not to apply them to blooming plants, neonicotinoids and other residual systemic insecticides may be applied for preventive control of lawn insect pests when spring-flowering weeds are present. Dietary exposure to neonicotinoids adversely affects bees, but the extent of hazard from field usage is controversial. We exposed colonies of the bumble bee Bombus impatiens to turf with blooming white clover that had been treated with clothianidin, a neonicotinoid, or with chlorantraniliprole, the first anthranilic diamide labeled for use on lawns. The sprays were applied at label rate and lightly irrigated. After residues had dried, colonies were confined to forage for six days, and then moved to a non-treated rural site to openly forage and develop. Colonies exposed to clothianidin-treated weedy turf had delayed weight gain and produced no new queens whereas those exposed to chlorantraniliprole-treated plots developed normally compared with controls. Neither bumble bees nor honey bees avoided foraging on treated white clover in open plots. Nectar from clover blooms directly contaminated by spray residues contained 171±44 ppb clothianidin. Notably, neither insecticide adversely impacted bee colonies confined on the treated turf after it had been mown to remove clover blooms present at the time of treatment, and new blooms had formed. Our results validate EPA label precautionary statements not to apply neonicotinoids to blooming nectar-producing plants if bees may visit the treatment area. Whatever systemic hazard through lawn weeds they may pose appears transitory, however, and direct hazard can be mitigated by adhering to label precautions, or if blooms inadvertently are contaminated, by mowing to remove them. Chlorantraniliprole usage on lawns appears non-hazardous to bumble bees. PMID:23776667

  8. Assessing insecticide hazard to bumble bees foraging on flowering weeds in treated lawns.

    PubMed

    Larson, Jonathan L; Redmond, Carl T; Potter, Daniel A

    2013-01-01

    Maintaining bee-friendly habitats in cities and suburbs can help conserve the vital pollination services of declining bee populations. Despite label precautions not to apply them to blooming plants, neonicotinoids and other residual systemic insecticides may be applied for preventive control of lawn insect pests when spring-flowering weeds are present. Dietary exposure to neonicotinoids adversely affects bees, but the extent of hazard from field usage is controversial. We exposed colonies of the bumble bee Bombus impatiens to turf with blooming white clover that had been treated with clothianidin, a neonicotinoid, or with chlorantraniliprole, the first anthranilic diamide labeled for use on lawns. The sprays were applied at label rate and lightly irrigated. After residues had dried, colonies were confined to forage for six days, and then moved to a non-treated rural site to openly forage and develop. Colonies exposed to clothianidin-treated weedy turf had delayed weight gain and produced no new queens whereas those exposed to chlorantraniliprole-treated plots developed normally compared with controls. Neither bumble bees nor honey bees avoided foraging on treated white clover in open plots. Nectar from clover blooms directly contaminated by spray residues contained 171±44 ppb clothianidin. Notably, neither insecticide adversely impacted bee colonies confined on the treated turf after it had been mown to remove clover blooms present at the time of treatment, and new blooms had formed. Our results validate EPA label precautionary statements not to apply neonicotinoids to blooming nectar-producing plants if bees may visit the treatment area. Whatever systemic hazard through lawn weeds they may pose appears transitory, however, and direct hazard can be mitigated by adhering to label precautions, or if blooms inadvertently are contaminated, by mowing to remove them. Chlorantraniliprole usage on lawns appears non-hazardous to bumble bees.

  9. Test of the invasive pathogen hypothesis of bumble bee decline in North America

    PubMed Central

    Cameron, Sydney A.; Lim, Haw Chuan; Lozier, Jeffrey D.; Duennes, Michelle A.; Thorp, Robbin

    2016-01-01

    Emergent fungal diseases are critical factors in global biodiversity declines. The fungal pathogen Nosema bombi was recently found to be widespread in declining species of North American bumble bees (Bombus), with circumstantial evidence suggesting an exotic introduction from Europe. This interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns of N. bombi in declining North American populations. Thus, the temporal and spatial emergence of N. bombi and its potential role in bumble bee decline remain speculative. We analyze Nosema prevalence and genetic variation in the United States and Europe from 1980, before an alleged introduction in the early 1990s, to 2011, extracting Nosema DNA from Bombus natural history collection specimens from across this time period. Nosema bombi prevalence increased significantly from low detectable frequency in the 1980s to significantly higher frequency in the mid- to late-1990s, corresponding to a period of reported massive infectious outbreak of N. bombi in commercial bumble bee rearing stocks in North America. Despite the increased frequency, we find no conclusive evidence of an exotic N. bombi origin based on genetic analysis of global Nosema populations; the widespread Nosema strain found currently in declining United States bumble bees was present in the United States before commercial colony trade. Notably, the US N. bombi is not detectably different from that found predominantly throughout Western Europe, with both regions characterized by low genetic diversity compared with high levels of diversity found in Asia, where commercial bee breeding activities are low or nonexistent. PMID:27044096

  10. Bumble bee species' responses to a targeted conservation measure depend on landscape context and habitat quality.

    PubMed

    Carvell, C; Osborne, J L; Bourke, A F G; Freeman, S N; Pywell, R F; Heard, M S

    2011-07-01

    The global decline of insect pollinators, especially bees, is cause for concern, and there is an urgent need for cost-effective conservation measures in agricultural landscapes. While landscape context and habitat quality are known to influence species richness and abundance of bees, there is a lack of evidence from manipulative field experiments on bees' responses to adaptive management across differently structured landscapes. We present the results of a large-scale study that investigated the effects of a targeted agri-environment scheme (AES) on bumble bees (Bombus spp.) over three years in the United Kingdom. Forage patches of different sizes were sown with a conservation flower mixture across eight sites covering a broad range of agricultural land use types. Species richness and worker densities (especially of the longer-tongued Bombus species for which the mixture was targeted) were significantly higher on sown forage patches than on existing non-crop control habitats throughout the three-year study, but the strength of this response depended on both the proportions of arable land and abundance of herbaceous forb species in the surrounding landscape. The size of sown patches also affected worker density, with smaller patches (0.25 ha) attracting higher densities of some species than larger patches (1.0 ha). Our models show that a targeted AES can deliver greater net benefits in more intensively farmed areas, in terms of the number and species richness of bumble bees supported, than in heterogeneous landscapes where other foraging habitats exist. These findings serve to strengthen the evidence base for extending agri-environment schemes to boost declining pollinator populations to a larger number of agricultural landscapes across the globe.

  11. Patterns of widespread decline in North American bumble bees

    PubMed Central

    Cameron, Sydney A.; Lozier, Jeffrey D.; Strange, James P.; Koch, Jonathan B.; Cordes, Nils; Solter, Leellen F.; Griswold, Terry L.

    2011-01-01

    Bumble bees (Bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. Fragmentary observations, however, have suggested population declines in several North American species. Despite rising concern over these observations in the United States, highlighted in a recent National Academy of Sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. Here, we report results of a 3-y interdisciplinary study of changing distributions, population genetic structure, and levels of pathogen infection in bumble bee populations across the United States. We compare current and historical distributions of eight species, compiling a database of >73,000 museum records for comparison with data from intensive nationwide surveys of >16,000 specimens. We show that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23–87%, some within the last 20 y. We also show that declining populations have significantly higher infection levels of the microsporidian pathogen Nosema bombi and lower genetic diversity compared with co-occurring populations of the stable (nondeclining) species. Higher pathogen prevalence and reduced genetic diversity are, thus, realistic predictors of these alarming patterns of decline in North America, although cause and effect remain uncertain. PMID:21199943

  12. Bumble bee parasite strains vary in resistance to phytochemicals.

    PubMed

    Palmer-Young, Evan C; Sadd, Ben M; Stevenson, Philip C; Irwin, Rebecca E; Adler, Lynn S

    2016-11-24

    Nectar and pollen contain diverse phytochemicals that can reduce disease in pollinators. However, prior studies showed variable effects of nectar chemicals on infection, which could reflect variable phytochemical resistance among parasite strains. Inter-strain variation in resistance could influence evolutionary interactions between plants, pollinators, and pollinator disease, but testing direct effects of phytochemicals on parasites requires elimination of variation between bees. Using cell cultures of the bumble bee parasite Crithidia bombi, we determined (1) growth-inhibiting effects of nine floral phytochemicals and (2) variation in phytochemical resistance among four parasite strains. C. bombi growth was unaffected by naturally occurring concentrations of the known antitrypanosomal phenolics gallic acid, caffeic acid, and chlorogenic acid. However, C. bombi growth was inhibited by anabasine, eugenol, and thymol. Strains varied >3-fold in phytochemical resistance, suggesting that selection for phytochemical resistance could drive parasite evolution. Inhibitory concentrations of thymol (4.53-22.2 ppm) were similar to concentrations in Thymus vulgaris nectar (mean 5.2 ppm). Exposure of C. bombi to naturally occurring levels of phytochemicals-either within bees or during parasite transmission via flowers-could influence infection in nature. Flowers that produce antiparasitic phytochemicals, including thymol, could potentially reduce infection in Bombus populations, thereby counteracting a possible contributor to pollinator decline.

  13. Patterns of widespread decline in North American bumble bees.

    PubMed

    Cameron, Sydney A; Lozier, Jeffrey D; Strange, James P; Koch, Jonathan B; Cordes, Nils; Solter, Leellen F; Griswold, Terry L

    2011-01-11

    Bumble bees (Bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. Fragmentary observations, however, have suggested population declines in several North American species. Despite rising concern over these observations in the United States, highlighted in a recent National Academy of Sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. Here, we report results of a 3-y interdisciplinary study of changing distributions, population genetic structure, and levels of pathogen infection in bumble bee populations across the United States. We compare current and historical distributions of eight species, compiling a database of >73,000 museum records for comparison with data from intensive nationwide surveys of >16,000 specimens. We show that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23-87%, some within the last 20 y. We also show that declining populations have significantly higher infection levels of the microsporidian pathogen Nosema bombi and lower genetic diversity compared with co-occurring populations of the stable (nondeclining) species. Higher pathogen prevalence and reduced genetic diversity are, thus, realistic predictors of these alarming patterns of decline in North America, although cause and effect remain uncertain.

  14. Bumble bee parasite strains vary in resistance to phytochemicals

    PubMed Central

    Palmer-Young, Evan C.; Sadd, Ben M.; Stevenson, Philip C.; Irwin, Rebecca E.; Adler, Lynn S.

    2016-01-01

    Nectar and pollen contain diverse phytochemicals that can reduce disease in pollinators. However, prior studies showed variable effects of nectar chemicals on infection, which could reflect variable phytochemical resistance among parasite strains. Inter-strain variation in resistance could influence evolutionary interactions between plants, pollinators, and pollinator disease, but testing direct effects of phytochemicals on parasites requires elimination of variation between bees. Using cell cultures of the bumble bee parasite Crithidia bombi, we determined (1) growth-inhibiting effects of nine floral phytochemicals and (2) variation in phytochemical resistance among four parasite strains. C. bombi growth was unaffected by naturally occurring concentrations of the known antitrypanosomal phenolics gallic acid, caffeic acid, and chlorogenic acid. However, C. bombi growth was inhibited by anabasine, eugenol, and thymol. Strains varied >3-fold in phytochemical resistance, suggesting that selection for phytochemical resistance could drive parasite evolution. Inhibitory concentrations of thymol (4.53–22.2 ppm) were similar to concentrations in Thymus vulgaris nectar (mean 5.2 ppm). Exposure of C. bombi to naturally occurring levels of phytochemicals—either within bees or during parasite transmission via flowers—could influence infection in nature. Flowers that produce antiparasitic phytochemicals, including thymol, could potentially reduce infection in Bombus populations, thereby counteracting a possible contributor to pollinator decline. PMID:27883009

  15. Problem solving by worker bumblebees Bombus impatiens (Hymenoptera: Apoidea).

    PubMed

    Mirwan, Hamida B; Kevan, Peter G

    2014-09-01

    During foraging, worker bumblebees are challenged by simple to complex tasks. Our goal was to determine whether bumblebees could successfully accomplish tasks that are more complex than those they would naturally encounter. Once the initial training to successfully manipulate a simple, artificial flower was completed, the bees were either challenged with a series of increasingly difficult tasks or with the most difficult task without the opportunity for prior learning. The first experiment demonstrated that the bees learned to slide or lift caps that prevented their access to the reinforcer sugar solution through a series of tasks with increasing complexity: moving one cap either to the right or to the left, or lifting it up. The second experiment demonstrated that the bees learned to push balls of escalating masses (diameters 1 and 1.27 cm) from the access to the hidden rewarding (sugar syrup) reservoir of artificial flowers. In both experiments, when bees with experience with only the simplest task (i.e. an artificial flower without a barrier to the reinforcer) were presented next with the most complex or difficult task, they failed. Only by proceeding through the series of increasingly difficult tasks were they able to succeed at the most difficult. We also noted idiosyncratic behaviours by individual bees in learning to succeed. Our results can be interpreted within the context of Skinnerian shaping and possibly scaffold learning.

  16. Honey bee viruses.

    PubMed

    Chen, Yan Ping; Siede, Reinhold

    2007-01-01

    Viruses are significant threats to the health and well-being of the honey bee, Apis mellifera. To alleviate the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Although knowledge of honey bee viruses has been accumulated considerably in the past three decades, a comprehensive review to compile the various aspects of bee viruses at the molecular level has not been reported. This chapter summarizes recent progress in the understanding of the morphology, genome organization, transmission, epidemiology, and pathogenesis of honey bee viruses as well as their interactions with their honey bee hosts. The future prospects of research of honey bee viruses are also discussed in detail. The chapter has been designed to provide researchers in the field with updated information about honey bee viruses and to serve as a starting point for future research.

  17. Inbreeding in Mimulus guttatus Reduces Visitation by Bumble Bee Pollinators

    PubMed Central

    Carr, David E.; Roulston, T’ai H.; Hart, Haley

    2014-01-01

    Inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. This study examined the effect of inbreeding in the mixed-mating annual Mimulus guttatus on visitation by pollinators (Bombus impatiens) in greenhouse experiments. Previous studies of M. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. Using controlled crosses, we produced inbred and outbred families from three different M. guttatus populations. We recorded the plant genotypes that bees visited and the number of flowers probed per visit. In our first experiment, bees were 31% more likely to visit outbred plants than those selfed for one generation and 43% more likely to visit outbred plants than those selfed for two generations. Inbreeding had only a small effect on the number of flowers probed once bees arrived at a genotype. These differences were explained partially by differences in mean floral display and mean flower size, but even when these variables were controlled statistically, the effect of inbreeding remained large and significant. In a second experiment we quantified pollen viability from inbred and self plants. Bees were 37–54% more likely to visit outbred plants, depending on the population, even when controlling for floral display size. Pollen viability proved to be as important as floral display in predicting pollinator visitation in one population, but the overall explanatory power of a multiple regression model was weak. Our data suggested that bees use cues in addition to display size, flower size, and pollen reward quality in their discrimination of inbred plants. Discrimination against inbred plants could have effects on plant fitness and thereby reinforce selection for outcrossing. Inbreeding in plant populations could also reduce resource quality for pollinators, potentially resulting in negative effects on pollinator populations. PMID:25036035

  18. Inbreeding in Mimulus guttatus reduces visitation by bumble bee pollinators.

    PubMed

    Carr, David E; Roulston, T'ai H; Hart, Haley

    2014-01-01

    Inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. This study examined the effect of inbreeding in the mixed-mating annual Mimulus guttatus on visitation by pollinators (Bombus impatiens) in greenhouse experiments. Previous studies of M. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. Using controlled crosses, we produced inbred and outbred families from three different M. guttatus populations. We recorded the plant genotypes that bees visited and the number of flowers probed per visit. In our first experiment, bees were 31% more likely to visit outbred plants than those selfed for one generation and 43% more likely to visit outbred plants than those selfed for two generations. Inbreeding had only a small effect on the number of flowers probed once bees arrived at a genotype. These differences were explained partially by differences in mean floral display and mean flower size, but even when these variables were controlled statistically, the effect of inbreeding remained large and significant. In a second experiment we quantified pollen viability from inbred and self plants. Bees were 37-54% more likely to visit outbred plants, depending on the population, even when controlling for floral display size. Pollen viability proved to be as important as floral display in predicting pollinator visitation in one population, but the overall explanatory power of a multiple regression model was weak. Our data suggested that bees use cues in addition to display size, flower size, and pollen reward quality in their discrimination of inbred plants. Discrimination against inbred plants could have effects on plant fitness and thereby reinforce selection for outcrossing. Inbreeding in plant populations could also reduce resource quality for pollinators, potentially resulting in negative effects on pollinator populations.

  19. Blackawton bees

    PubMed Central

    Blackawton, P. S.; Airzee, S.; Allen, A.; Baker, S.; Berrow, A.; Blair, C.; Churchill, M.; Coles, J.; Cumming, R. F.-J.; Fraquelli, L.; Hackford, C.; Hinton Mellor, A.; Hutchcroft, M.; Ireland, B.; Jewsbury, D.; Littlejohns, A.; Littlejohns, G. M.; Lotto, M.; McKeown, J.; O'Toole, A.; Richards, H.; Robbins-Davey, L.; Roblyn, S.; Rodwell-Lynn, H.; Schenck, D.; Springer, J.; Wishy, A.; Rodwell-Lynn, T.; Strudwick, D.; Lotto, R. B.

    2011-01-01

    Background Real science has the potential to not only amaze, but also transform the way one thinks of the world and oneself. This is because the process of science is little different from the deeply resonant, natural processes of play. Play enables humans (and other mammals) to discover (and create) relationships and patterns. When one adds rules to play, a game is created. This is science: the process of playing with rules that enables one to reveal previously unseen patterns of relationships that extend our collective understanding of nature and human nature. When thought of in this way, science education becomes a more enlightened and intuitive process of asking questions and devising games to address those questions. But, because the outcome of all game-playing is unpredictable, supporting this ‘messyness’, which is the engine of science, is critical to good science education (and indeed creative education generally). Indeed, we have learned that doing ‘real’ science in public spaces can stimulate tremendous interest in children and adults in understanding the processes by which we make sense of the world. The present study (on the vision of bumble-bees) goes even further, since it was not only performed outside my laboratory (in a Norman church in the southwest of England), but the ‘games’ were themselves devised in collaboration with 25 8- to 10-year-old children. They asked the questions, hypothesized the answers, designed the games (in other words, the experiments) to test these hypotheses and analysed the data. They also drew the figures (in coloured pencil) and wrote the paper. Their headteacher (Dave Strudwick) and I devised the educational programme (we call ‘i,scientist’), and I trained the bees and transcribed the childrens' words into text (which was done with smaller groups of children at the school's local village pub). So what follows is a novel study (scientifically and conceptually) in ‘kids speak’ without references to past

  20. Flowers help bees cope with uncertainty: signal detection and the function of floral complexity

    PubMed Central

    Leonard, Anne S.; Dornhaus, Anna; Papaj, Daniel R.

    2011-01-01

    Plants often attract pollinators with floral displays composed of visual, olfactory, tactile and gustatory stimuli. Since pollinators' responses to each of these stimuli are usually studied independently, the question of why plants produce multi-component floral displays remains relatively unexplored. Here we used signal detection theory to test the hypothesis that complex displays reduce a pollinator's uncertainty about the floral signal. Specifically, we asked whether one component of the floral display, scent, improved a bee's certainty about the value of another component, color hue. We first trained two groups of bumble bees (Bombus impatiens Cresson) to discriminate between rewarding and unrewarding artificial flowers of slightly different hues in the presence vs absence of scent. In a test phase, we presented these bees with a gradient of floral hues and assessed their ability to identify the hue rewarded during training. We interpreted the extent to which bees' preferences were biased away from the unrewarding hue (‘peak shift’) as an indicator of uncertainty in color discrimination. Our data show that the presence of an olfactory signal reduces uncertainty regarding color: not only was color learning facilitated on scented flowers but also bees showed a lower amount of peak shift in the presence of scent. We explore potential mechanisms by which scent might reduce uncertainty about color, and discuss the broader significance of our results for our understanding of signal evolution. PMID:21147975

  1. Foraging Bumble Bees Weigh the Reliability of Personal and Social Information.

    PubMed

    Dunlap, Aimee S; Nielsen, Matthew E; Dornhaus, Anna; Papaj, Daniel R

    2016-05-09

    Many animals, including insects, make decisions using both personally gathered information and social information derived from the behavior of other, usually conspecific, individuals [1]. Moreover, animals adjust use of social versus personal information appropriately under a variety of experimental conditions [2-5]. An important factor in how information is used is the information's reliability, that is, how consistently the information is correlated with something of relevance in the environment [6]. The reliability of information determines which signals should be attended to during communication [6-9], which types of stimuli animals should learn about, and even whether learning should evolve [10, 11]. Here, we show that bumble bees (Bombus impatiens) account for the reliability of personally acquired information (which flower color was previously associated with reward) and social information (which flowers are chosen by other bees) in making foraging decisions; however, the two types of information are not treated equally. Bees prefer to use social information if it predicts a reward at all, but if social information becomes entirely unreliable, flower color will be used instead. This greater sensitivity to the reliability of social information, and avoidance of conspecifics in some cases, may reflect the specific ecological circumstances of bee foraging. Overall, the bees' ability to make decisions based on both personally acquired and socially derived information, and the relative reliability of both, demonstrates a new level of sophistication and flexibility in animal, particularly insect, decision-making.

  2. Flowers help bees cope with uncertainty: signal detection and the function of floral complexity.

    PubMed

    Leonard, Anne S; Dornhaus, Anna; Papaj, Daniel R

    2011-01-01

    Plants often attract pollinators with floral displays composed of visual, olfactory, tactile and gustatory stimuli. Since pollinators' responses to each of these stimuli are usually studied independently, the question of why plants produce multi-component floral displays remains relatively unexplored. Here we used signal detection theory to test the hypothesis that complex displays reduce a pollinator's uncertainty about the floral signal. Specifically, we asked whether one component of the floral display, scent, improved a bee's certainty about the value of another component, color hue. We first trained two groups of bumble bees (Bombus impatiens Cresson) to discriminate between rewarding and unrewarding artificial flowers of slightly different hues in the presence vs absence of scent. In a test phase, we presented these bees with a gradient of floral hues and assessed their ability to identify the hue rewarded during training. We interpreted the extent to which bees' preferences were biased away from the unrewarding hue ('peak shift') as an indicator of uncertainty in color discrimination. Our data show that the presence of an olfactory signal reduces uncertainty regarding color: not only was color learning facilitated on scented flowers but also bees showed a lower amount of peak shift in the presence of scent. We explore potential mechanisms by which scent might reduce uncertainty about color, and discuss the broader significance of our results for our understanding of signal evolution.

  3. The formulation makes the honey bee poison.

    PubMed

    Mullin, Christopher A; Chen, Jing; Fine, Julia D; Frazier, Maryann T; Frazier, James L

    2015-05-01

    Dr. Fumio Matsumura's legacy embraced a passion for exploring environmental impacts of agrochemicals on non-target species such as bees. Why most formulations are more toxic to bees than respective active ingredients and how pesticides interact to cause pollinator decline cannot be answered without understanding the prevailing environmental chemical background to which bees are exposed. Modern pesticide formulations and seed treatments, particularly when multiple active ingredients are blended, require proprietary adjuvants and inert ingredients to achieve high efficacy for targeted pests. Although we have found over 130 different pesticides and metabolites in beehive samples, no individual pesticide or amount correlates with recent bee declines. Recently we have shown that honey bees are sensitive to organosilicone surfactants, nonylphenol polyethoxylates and the solvent N-methyl-2-pyrrolidone (NMP), widespread co-formulants used in agrochemicals and frequent pollutants within the beehive. Effects include learning impairment for adult bees and chronic toxicity in larval feeding bioassays. Multi-billion pounds of formulation ingredients like NMP are used and released into US environments. These synthetic organic chemicals are generally recognized as safe, have no mandated tolerances, and residues remain largely unmonitored. In contrast to finding about 70% of the pesticide active ingredients searched for in our pesticide analysis of beehive samples, we have found 100% of the other formulation ingredients targeted for analysis. These 'inerts' overwhelm the chemical burden from active pesticide, drug and personal care ingredients with which they are formulated. Honey bees serve as an optimal terrestrial bioindicator to determine if 'the formulation and not just the dose makes the poison'. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. How floral odours are learned inside the bumblebee ( Bombus terrestris) nest

    NASA Astrophysics Data System (ADS)

    Molet, Mathieu; Chittka, Lars; Raine, Nigel E.

    2009-02-01

    Recruitment in social insects often involves not only inducing nestmates to leave the nest, but also communicating crucial information about finding profitable food sources. Although bumblebees transmit chemosensory information (floral scent), the transmission mechanism is unknown as mouth-to-mouth fluid transfer (as in honeybees) does not occur. Because recruiting bumblebees release a pheromone in the nest that triggers foraging in previously inactive workers, we tested whether this pheromone helps workers learn currently rewarding floral odours, as found in food social learning in rats. We exposed colonies to artificial recruitment pheromone, paired with anise scent. The pheromone did not facilitate learning of floral scent. However, we found that releasing floral scent in the air of the colony was sufficient to trigger learning and that learning performance was improved when the chemosensory cue was provided in the nectar in honeypots; probably because it guarantees a tighter link between scent and reward, and possibly because gustatory cues are involved in addition to olfaction. Scent learning was maximal when anise-scented nectar was brought into the nest by demonstrator foragers, suggesting that previously unidentified cues provided by successful foragers play an important role in nestmates learning new floral odours.

  5. Mite species inhabiting commercial bumblebee (Bombus terrestris) nests in Polish greenhouses.

    PubMed

    Rożej, Elżbieta; Witaliński, Wojciech; Szentgyörgyi, Hajnalka; Wantuch, Marta; Moroń, Dawid; Woyciechowski, Michal

    2012-03-01

    Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.

  6. Male bumblebees, Bombus terrestris, perform equally well as workers in a serial colour-learning task

    PubMed Central

    Wolf, Stephan; Chittka, Lars

    2016-01-01

    The learning capacities of males and females may differ with sex-specific behavioural requirements. Bumblebees provide a useful model system to explore how different lifestyles are reflected in learning abilities, because their (female but sterile) workers and males engage in fundamentally different behaviour routines. Bumblebee males, like workers, embark on active flower foraging but in contrast to workers they have to trade off their feeding with mate search, potentially affecting their abilities to learn and utilize floral cues efficiently during foraging. We used a serial colour-learning task with freely flying males and workers to compare their ability to flexibly learn visual floral cues with reward in a foraging scenario that changed over time. Male bumblebees did not differ from workers in both their learning speed and their ability to overcome previously acquired associations, when these ceased to predict reward. In all foraging tasks we found a significant improvement in choice accuracy in both sexes over the course of the training. In both sexes, the characteristics of the foraging performance depended largely on the colour difference of the two presented feeder types. Large colour distances entailed fast and reliable learning of the rewarding feeders whereas choice accuracy on highly similar colours improved significantly more slowly. Conversely, switching from a learned feeder type to a novel one was fastest for similar feeder colours and slow for highly different ones. Overall, we show that behavioural sex dimorphism in bumblebees did not affect their learning abilities beyond the mating context. We discuss the possible drivers and limitations shaping the foraging abilities of males and workers and implications for pollination ecology. We also suggest stingless male bumblebees as an advantageous alternative model system for the study of pollinator cognition. PMID:26877542

  7. Bees as Biosensors: Chemosensory Ability, Honey Bee Monitoring Systems, and Emergent Sensor Technologies Derived from the Pollinator Syndrome.

    PubMed

    Bromenshenk, Jerry J; Henderson, Colin B; Seccomb, Robert A; Welch, Phillip M; Debnam, Scott E; Firth, David R

    2015-10-30

    This review focuses on critical milestones in the development path for the use of bees, mainly honey bees and bumble bees, as sentinels and biosensors. These keystone species comprise the most abundant pollinators of agro-ecosystems. Pollinating 70%-80% of flowering terrestrial plants, bees and other insects propel the reproduction and survival of plants and themselves, as well as improve the quantity and quality of seeds, nuts, and fruits that feed birds, wildlife, and us. Flowers provide insects with energy, nutrients, and shelter, while pollinators are essential to global ecosystem productivity and stability. A rich and diverse milieu of chemical signals establishes and maintains this intimate partnership. Observations of bee odor search behavior extend back to Aristotle. In the past two decades great strides have been made in methods and instrumentation for the study and exploitation of bee search behavior and for examining intra-organismal chemical communication signals. In particular, bees can be trained to search for and localize sources for a variety of chemicals, which when coupled with emerging tracking and mapping technologies create novel potential for research, as well as bee and crop management.

  8. Bees as Biosensors: Chemosensory Ability, Honey Bee Monitoring Systems, and Emergent Sensor Technologies Derived from the Pollinator Syndrome

    PubMed Central

    Bromenshenk, Jerry J.; Henderson, Colin B.; Seccomb, Robert A.; Welch, Phillip M.; Debnam, Scott E.; Firth, David R.

    2015-01-01

    This review focuses on critical milestones in the development path for the use of bees, mainly honey bees and bumble bees, as sentinels and biosensors. These keystone species comprise the most abundant pollinators of agro-ecosystems. Pollinating 70%–80% of flowering terrestrial plants, bees and other insects propel the reproduction and survival of plants and themselves, as well as improve the quantity and quality of seeds, nuts, and fruits that feed birds, wildlife, and us. Flowers provide insects with energy, nutrients, and shelter, while pollinators are essential to global ecosystem productivity and stability. A rich and diverse milieu of chemical signals establishes and maintains this intimate partnership. Observations of bee odor search behavior extend back to Aristotle. In the past two decades great strides have been made in methods and instrumentation for the study and exploitation of bee search behavior and for examining intra-organismal chemical communication signals. In particular, bees can be trained to search for and localize sources for a variety of chemicals, which when coupled with emerging tracking and mapping technologies create novel potential for research, as well as bee and crop management. PMID:26529030

  9. Hitting an Unintended Target: Phylogeography of Bombus brasiliensis Lepeletier, 1836 and the First New Brazilian Bumblebee Species in a Century (Hymenoptera: Apidae)

    PubMed Central

    Santos Júnior, José Eustáquio; Santos, Fabrício R.; Silveira, Fernando A.

    2015-01-01

    This work tested whether or not populations of Bombus brasiliensis isolated on mountain tops of southeastern Brazil belonged to the same species as populations widespread in lowland areas in the Atlantic coast and westward along the Paraná-river valley. Phylogeographic and population genetic analyses showed that those populations were all conspecific. However, they revealed a previously unrecognized, apparently rare, and potentially endangered species in one of the most threatened biodiversity hotspots of the World, the Brazilian Atlantic Forest. This species is described here as Bombus bahiensis sp. n., and included in a revised key for the identification of the bumblebee species known to occur in Brazil. Phylogenetic analyses based on two mtDNA markers suggest this new species to be sister to B. brasiliensis, from which its workers and queens can be easily distinguished by the lack of a yellow hair-band on the first metasomal tergum. The results presented here are consistent with the hypothesis that B. bahiensis sp. n. may have originated from an ancestral population isolated in an evergreen-forest refuge (the so-called Bahia refuge) during cold, dry periods of the Pleistocene. This refuge is also known as an important area of endemism for several animal taxa, including other bees. Secondary contact between B. bahiensis and B. brasiliensis may be presently prevented by a strip of semi-deciduous forest in a climate zone characterized by relatively long dry seasons. Considering the relatively limited range of this new species and the current anthropic pressure on its environment, attention should be given to its conservation status. PMID:25992624

  10. Widespread occurrence of honey bee pathogens in solitary bees.

    PubMed

    Ravoet, Jorgen; De Smet, Lina; Meeus, Ivan; Smagghe, Guy; Wenseleers, Tom; de Graaf, Dirk C

    2014-10-01

    Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens.

  11. Individual lifetime pollen and nectar foraging preferences in bumble bees

    NASA Astrophysics Data System (ADS)

    Hagbery, Jessica; Nieh, James C.

    2012-10-01

    Foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. However, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. Using Bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual foragers exhibit consistent lifetime foraging preferences. Based upon the distribution of foraging preferences, we defined three forager types (pollen specialists, nectar specialists, and generalists). In unmanipulated colonies, 16-36 % of individuals specialized (≥90 % of visits) on nectar or pollen only. On its first day of foraging, an individual's foraging choices (nectar only, pollen only, or nectar and pollen) significantly predicted its lifetime foraging preferences. Foragers that only collected pollen on their first day of foraging made 1.61- to 1.67-fold more lifetime pollen foraging visits (as a proportion of total trips) than foragers that only collected nectar on their first foraging day. Foragers were significantly larger than bees that stayed only in the nest. We also determined the effect of removing pollen specialists at early (brood present) or later (brood absent) stages in colony life. These results suggest that generalists can alter their foraging preferences in response to the loss of a small subset of foragers. Thus, bumble bees exhibit individual lifetime foraging preferences that are established early in life, but generalists may be able to adapt to colony needs.

  12. Individual lifetime pollen and nectar foraging preferences in bumble bees.

    PubMed

    Hagbery, Jessica; Nieh, James C

    2012-10-01

    Foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. However, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. Using Bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual foragers exhibit consistent lifetime foraging preferences. Based upon the distribution of foraging preferences, we defined three forager types (pollen specialists, nectar specialists, and generalists). In unmanipulated colonies, 16-36 % of individuals specialized (≥90 % of visits) on nectar or pollen only. On its first day of foraging, an individual's foraging choices (nectar only, pollen only, or nectar and pollen) significantly predicted its lifetime foraging preferences. Foragers that only collected pollen on their first day of foraging made 1.61- to 1.67-fold more lifetime pollen foraging visits (as a proportion of total trips) than foragers that only collected nectar on their first foraging day. Foragers were significantly larger than bees that stayed only in the nest. We also determined the effect of removing pollen specialists at early (brood present) or later (brood absent) stages in colony life. These results suggest that generalists can alter their foraging preferences in response to the loss of a small subset of foragers. Thus, bumble bees exhibit individual lifetime foraging preferences that are established early in life, but generalists may be able to adapt to colony needs.

  13. Chronic Exposure of Imidacloprid and Clothianidin Reduce Queen Survival, Foraging, and Nectar Storing in Colonies of Bombus impatiens

    PubMed Central

    Scholer, Jamison; Krischik, Vera

    2014-01-01

    In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin), 10 (14 I, 9 C), 20 (16 I, 17C), 50 (71 I, 39 C) and 100 (127 I, 76 C) ppb imidacloprid or clothianidin in sugar syrup (50%). These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower). At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb–100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C) ppb was the statistically significant reduction in queen survival (37% I, 56% C) ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14) ppb I and 50 (39) ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage) that result in detrimental effects on colonies (queen survival and colony weight). Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb. PMID:24643057

  14. Chronic exposure of imidacloprid and clothianidin reduce queen survival, foraging, and nectar storing in colonies of Bombus impatiens.

    PubMed

    Scholer, Jamison; Krischik, Vera

    2014-01-01

    In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin), 10 (14 I, 9 C), 20 (16 I, 17C), 50 (71 I, 39 C) and 100 (127 I, 76 C) ppb imidacloprid or clothianidin in sugar syrup (50%). These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower). At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb-100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C) ppb was the statistically significant reduction in queen survival (37% I, 56% C) ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14) ppb I and 50 (39) ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage) that result in detrimental effects on colonies (queen survival and colony weight). Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb.

  15. The Bee Microbiome: Impact on Bee Health and Model for Evolution and Ecology of Host-Microbe Interactions.

    PubMed

    Engel, Philipp; Kwong, Waldan K; McFrederick, Quinn; Anderson, Kirk E; Barribeau, Seth Michael; Chandler, James Angus; Cornman, R Scott; Dainat, Jacques; de Miranda, Joachim R; Doublet, Vincent; Emery, Olivier; Evans, Jay D; Farinelli, Laurent; Flenniken, Michelle L; Granberg, Fredrik; Grasis, Juris A; Gauthier, Laurent; Hayer, Juliette; Koch, Hauke; Kocher, Sarah; Martinson, Vincent G; Moran, Nancy; Munoz-Torres, Monica; Newton, Irene; Paxton, Robert J; Powell, Eli; Sadd, Ben M; Schmid-Hempel, Paul; Schmid-Hempel, Regula; Song, Se Jin; Schwarz, Ryan S; vanEngelsdorp, Dennis; Dainat, Benjamin

    2016-04-26

    As pollinators, bees are cornerstones for terrestrial ecosystem stability and key components in agricultural productivity. All animals, including bees, are associated with a diverse community of microbes, commonly referred to as the microbiome. The bee microbiome is likely to be a crucial factor affecting host health. However, with the exception of a few pathogens, the impacts of most members of the bee microbiome on host health are poorly understood. Further, the evolutionary and ecological forces that shape and change the microbiome are unclear. Here, we discuss recent progress in our understanding of the bee microbiome, and we present challenges associated with its investigation. We conclude that global coordination of research efforts is needed to fully understand the complex and highly dynamic nature of the interplay between the bee microbiome, its host, and the environment. High-throughput sequencing technologies are ideal for exploring complex biological systems, including host-microbe interactions. To maximize their value and to improve assessment of the factors affecting bee health, sequence data should be archived, curated, and analyzed in ways that promote the synthesis of different studies. To this end, the BeeBiome consortium aims to develop an online database which would provide reference sequences, archive metadata, and host analytical resources. The goal would be to support applied and fundamental research on bees and their associated microbes and to provide a collaborative framework for sharing primary data from different research programs, thus furthering our understanding of the bee microbiome and its impact on pollinator health. Copyright © 2016 Engel et al.

  16. Surplus nectar available for subalpine bumble bee colony growth.

    PubMed

    Elliott, Susan E

    2009-12-01

    Mutualisms may cause coupled population expansion or decline if both partners respond to variation in the other's abundance. Many studies have shown how the abundance of animal mutualists affects plant reproduction, but less is known about how the abundance of plant mutualists affects animal reproduction. Over 2 yr, I compared reproduction of the bumble bee, Bombus appositus, across meadows that varied naturally in flower density, and I compared reproduction between fed colonies and unfed control colonies. Colony reproduction (gyne, worker, and male production) was constant across meadows that varied naturally in flower density. Forager densities per flower did not vary among meadows, and daily nectar depletion was consistently low across meadows, suggesting that bees had ample nectar in all meadows. However, colonies directly fed with supplemental nectar and pollen generally produced over twice as many gynes as control colonies. Feeding did not affect male or worker production. Although colonies may benefit from food supplementation at the nest, it is possible that they may not benefit from additional flowers because they have too few workers to collect extra resources.

  17. Deep Sequencing and Ecological Characterization of Gut Microbial Communities of Diverse Bumble Bee Species

    PubMed Central

    Lim, Haw Chuan; Chu, Chia-Ching; Seufferheld, Manfredo J.; Cameron, Sydney A.

    2015-01-01

    Gut bacterial communities of bumble bees are correlated with defense against pathogens. Further understanding this host-microbe association is vitally important as bumble bees are currently experiencing global population declines, potentially due in part to emergent diseases. In this study, we used pyrosequencing and community fingerprinting (ARISA) to characterize the gut microbial communities of nine bumble species from across the Bombus phylogeny. Overall, we delimited 74 bacterial taxa (operational taxonomic units or OTUs) belonging to Betaproteobacteria, Gammaproteobacteria, Bacilli, Actinobacteria, Flavobacteria and Alphaproteobacteria. Each bacterial community was taxonomically simple, containing an average of 1.9 common (relative abundance per sample > 5%) bacterial OTUs. The most abundant and prevalent (occurring in 92% of the samples) bacterial OTU, based on 16S rRNA sequences, closely matched that of the previously described Betaproteobacteria species Snodgrassella alvi. Bacteria that were first described in bee-related external environments dominated a number of gut bacterial communities, suggesting that they are not strictly dependent on the internal gut environment. The ARISA data showed a correlation between bacterial community structures and the geographic locations where the bees were sampled, suggesting that at least a subset of the bacterial species may be transmitted environmentally. Using light and fluorescent microscopy, we demonstrated that the gut bacteria form a biofilm on the internal epithelial surface of the ileum, corroborating results obtained from Apis mellifera. PMID:25768110

  18. Native bees provide insurance against ongoing honey bee losses.

    PubMed

    Winfree, Rachael; Williams, Neal M; Dushoff, Jonathan; Kremen, Claire

    2007-11-01

    One of the values of biodiversity is that it may provide 'biological insurance' for services currently rendered by domesticated species or technology. We used crop pollination as a model system, and investigated whether the loss of a domesticated pollinator (the honey bee) could be compensated for by native, wild bee species. We measured pollination provided to watermelon crops at 23 farms in New Jersey and Pennsylvania, USA, and used a simulation model to separate the pollen provided by honey bees and native bees. Simulation results predict that native bees alone provide sufficient pollination at > 90% of the farms studied. Furthermore, empirical total pollen deposition at flowers was strongly, significantly correlated with native bee visitation but not with honey bee visitation. The honey bee is currently undergoing extensive die-offs because of Colony Collapse Disorder. We predict that in our region native bees will buffer potential declines in agricultural production because of honey bee losses.

  19. One World: Service Bees

    ERIC Educational Resources Information Center

    Thomason, Rhonda

    2009-01-01

    Bees are a vital part of the ecology. People of conscience are a vital part of society. In Nina Frenkel's "One World" poster, the bee is also a metaphor for the role of the individual in a diverse society. This article presents a lesson that uses Frenkel's poster to help early-grades students connect these ideas and explore both the importance of…

  20. One World: Service Bees

    ERIC Educational Resources Information Center

    Thomason, Rhonda

    2009-01-01

    Bees are a vital part of the ecology. People of conscience are a vital part of society. In Nina Frenkel's "One World" poster, the bee is also a metaphor for the role of the individual in a diverse society. This article presents a lesson that uses Frenkel's poster to help early-grades students connect these ideas and explore both the importance of…

  1. Diversity in bee (Hymenoptera: Apoidea) and social wasp (Hymenoptera: Vespidae, Polistinae) community in "campos rupestres", Bahia, Brazil.

    PubMed

    da Silva-Pereira, Vivane; Santos, Gilberto M M

    2006-01-01

    Hymenoptera such as bees and social wasps are regular floral visitors in "campos rupestres" vegetation. A community of bees and social wasps was studied during floral visitation in an area of "campos rupestres", at Chapada Diamantina, BA, Brazil, from September 2001 to April 2002. The community was described in relation to diversity, evenness, and dominance rank, considering the individuals abundance (H' = 2.14/ J' = 0.55) and biomass (H' = 2.34/ J' = 0.60). Thirty nine bee (588 individuals/ 15.742 g) and 11 social wasp species (52 individuals/ 2.156 g) were collected, being the first report of social wasps for the Brazilian "campos rupestres". The main species regarding number of individuals were Trigona spinipes (Fabricius), Apis mellifera L., Frieseomelitta francoi (Moure), and Bombus brevivillus Franklin. About 48% of the species were represented by a single individual. There was an inversion in the dominance rank when the species biomass was considered. B. brevivillus, A. mellifera, T spinipes, and other species represented by 15 individuals or less, such as the social wasps Synoeca cyanea (Olivier), Polistes canadensis (L.) and Myschocyttarus drewseni (Saussure), and the bees Eufriesea nigrohirta (Friese), Xylocopa grisescens Lepeletier and Megachile (Pseudocentron) sp.l were the predominant species. The use of biomass in diversity analysis permitted to detect differences in the relative contribution of species in hierarchy dominance. The comparison between bee faunas from different areas indicates a large similarity of the sampled fauna in Palmeiras (Bahia State) with neighboring ecosystems, although with low values of similarity.

  2. Habitat and forage associations of a naturally colonising insect pollinator, the tree bumblebee Bombus hypnorum.

    PubMed

    Crowther, Liam P; Hein, Pierre-Louis; Bourke, Andrew F G

    2014-01-01

    Bumblebees (Bombus species) are major pollinators of commercial crops and wildflowers but factors affecting their abundance, including causes of recent population declines, remain unclear. Investigating the ecology of species with expanding ranges provides a potentially powerful means of elucidating these factors. Such species may also bring novel pollination services to their new ranges. We therefore investigated landscape-scale habitat use and foraging preferences of the Tree Bumblebee, B. hypnorum, a recent natural colonist that has rapidly expanded its range in the UK over the past decade. Counts of B. hypnorum and six other Bombus species were made in March-June 2012 within a mixed landscape in south-eastern Norfolk, UK. The extent of different landscape elements around each transect was quantified at three scales (250 m, 500 m and 1500 m). We then identified the landscape elements that best predicted the density of B. hypnorum and other Bombus species. At the best fitting scale (250 m), B. hypnorum density was significantly positively associated with extent of both urban and woodland cover and significantly negatively associated with extent of oilseed rape cover. This combination of landscape predictors was unique to B. hypnorum. Urban and woodland cover were associated with B. hypnorum density at three and two, respectively, of the three scales studied. Relative to other Bombus species, B. hypnorum exhibited a significantly higher foraging preference for two flowering trees, Crataegus monogyna and Prunus spinosa, and significantly lower preferences for Brassica napus, Glechoma hederacea and Lamium album. Our study provides novel, quantitative support for an association of B. hypnorum with urban and woodland landscape elements. Range expansion in B. hypnorum appears to depend, on exploitation of widespread habitats underutilised by native Bombus species, suggesting B. hypnorum will readily co-exist with these species. These findings suggest that management

  3. Habitat and Forage Associations of a Naturally Colonising Insect Pollinator, the Tree Bumblebee Bombus hypnorum

    PubMed Central

    Crowther, Liam P.; Hein, Pierre-Louis; Bourke, Andrew F. G.

    2014-01-01

    Bumblebees (Bombus species) are major pollinators of commercial crops and wildflowers but factors affecting their abundance, including causes of recent population declines, remain unclear. Investigating the ecology of species with expanding ranges provides a potentially powerful means of elucidating these factors. Such species may also bring novel pollination services to their new ranges. We therefore investigated landscape-scale habitat use and foraging preferences of the Tree Bumblebee, B. hypnorum, a recent natural colonist that has rapidly expanded its range in the UK over the past decade. Counts of B. hypnorum and six other Bombus species were made in March-June 2012 within a mixed landscape in south-eastern Norfolk, UK. The extent of different landscape elements around each transect was quantified at three scales (250 m, 500 m and 1500 m). We then identified the landscape elements that best predicted the density of B. hypnorum and other Bombus species. At the best fitting scale (250 m), B. hypnorum density was significantly positively associated with extent of both urban and woodland cover and significantly negatively associated with extent of oilseed rape cover. This combination of landscape predictors was unique to B. hypnorum. Urban and woodland cover were associated with B. hypnorum density at three and two, respectively, of the three scales studied. Relative to other Bombus species, B. hypnorum exhibited a significantly higher foraging preference for two flowering trees, Crataegus monogyna and Prunus spinosa, and significantly lower preferences for Brassica napus, Glechoma hederacea and Lamium album. Our study provides novel, quantitative support for an association of B. hypnorum with urban and woodland landscape elements. Range expansion in B. hypnorum appears to depend, on exploitation of widespread habitats underutilised by native Bombus species, suggesting B. hypnorum will readily co-exist with these species. These findings suggest that management

  4. Variable effects of nicotine, anabasine, and their interactions on parasitized bumble bees

    PubMed Central

    Thorburn, Lukas P.; Adler, Lynn S.; Irwin, Rebecca E.; Palmer-Young, Evan C.

    2015-01-01

    Secondary metabolites in floral nectar have been shown to reduce parasite load in two common bumble bee species. Previous studies on the effects of nectar secondary metabolites on parasitized bees have focused on single compounds in isolation; however, in nature, bees are simultaneously exposed to multiple compounds. We tested for interactions between the effects of two alkaloids found in the nectar of Nicotiana spp. plants, nicotine and anabasine, on parasite load and mortality in bumble bees ( Bombus impatiens) infected with the intestinal parasite Crithidia bombi. Adult worker bees inoculated with C. bombi were fed nicotine and anabasine diet treatments in a factorial design, resulting in four nectar treatment combinations:  2 ppm nicotine, 5 ppm anabasine, 2ppm nicotine and 5 ppm anabasine together, or a control alkaloid-free solution. We conducted the experiment twice: first, with bees incubated under variable environmental conditions (‘Variable’; temperatures varied from 10-35°C with ambient lighting); and second, under carefully controlled environmental conditions (‘Stable’; 27°C incubator, constant darkness). In ‘Variable’, each alkaloid alone significantly decreased parasite loads, but this effect was not realized with the alkaloids in combination, suggesting an antagonistic interaction. Nicotine but not anabasine significantly increased mortality, and the two compounds had no interactive effects on mortality. In ‘Stable’, nicotine significantly increased parasite loads, the opposite of its effect in ‘Variable’. While not significant, the relationship between anabasine and parasite loads was also positive. Interactive effects between the two alkaloids on parasite load were non-significant, but the pattern of antagonistic interaction was similar to that in the variable experiment. Neither alkaloid, nor their interaction, significantly affected mortality under controlled conditions. Our results do not indicate synergy between Nicotiana

  5. The innate responses of bumble bees to flower patterns: separating the nectar guide from the nectary changes bee movements and search time

    NASA Astrophysics Data System (ADS)

    Goodale, Eben; Kim, Edward; Nabors, Annika; Henrichon, Sara; Nieh, James C.

    2014-06-01

    Nectar guides can enhance pollinator efficiency and plant fitness by allowing pollinators to more rapidly find and remember the location of floral nectar. We tested if a radiating nectar guide around a nectary would enhance the ability of naïve bumble bee foragers to find nectar. Most experiments that test nectar guide efficacy, specifically radiating linear guides, have used guides positioned around the center of a radially symmetric flower, where nectaries are often found. However, the flower center may be intrinsically attractive. We therefore used an off-center guide and nectary and compared "conjunct" feeders with a nectar guide surrounding the nectary to "disjunct" feeders with a nectar guide separated from the nectary. We focused on the innate response of novice bee foragers that had never previously visited such feeders. We hypothesized that a disjunct nectar guide would conflict with the visual information provided by the nectary and negatively affect foraging. Approximately, equal numbers of bumble bees ( Bombus impatiens) found nectar on both feeder types. On disjunct feeders, however, unsuccessful foragers spent significantly more time (on average 1.6-fold longer) searching for nectar than any other forager group. Successful foragers on disjunct feeders approached these feeders from random directions unlike successful foragers on conjunct feeders, which preferentially approached the combined nectary and nectar guide. Thus, the nectary and a surrounding nectar guide can be considered a combination of two signals that attract naïve foragers even when not in the floral center.

  6. Queen pheromones modulate DNA methyltransferase activity in bee and ant workers

    PubMed Central

    Holman, Luke; Trontti, Kalevi; Helanterä, Heikki

    2016-01-01

    DNA methylation is emerging as an important regulator of polyphenism in the social insects. Research has concentrated on differences in methylation between queens and workers, though we hypothesized that methylation is involved in mediating other flexible phenotypes, including pheromone-dependent changes in worker behaviour and physiology. Here, we find that exposure to queen pheromone affects the expression of two DNA methyltransferase genes in Apis mellifera honeybees and in two species of Lasius ants, but not in Bombus terrestris bumblebees. These results suggest that queen pheromones influence the worker methylome, pointing to a novel proximate mechanism for these key social signals. PMID:26814223

  7. Queen pheromones modulate DNA methyltransferase activity in bee and ant workers.

    PubMed

    Holman, Luke; Trontti, Kalevi; Helanterä, Heikki

    2016-01-01

    DNA methylation is emerging as an important regulator of polyphenism in the social insects. Research has concentrated on differences in methylation between queens and workers, though we hypothesized that methylation is involved in mediating other flexible phenotypes, including pheromone-dependent changes in worker behaviour and physiology. Here, we find that exposure to queen pheromone affects the expression of two DNA methyltransferase genes in Apis mellifera honeybees and in two species of Lasius ants, but not in Bombus terrestris bumblebees. These results suggest that queen pheromones influence the worker methylome, pointing to a novel proximate mechanism for these key social signals. © 2016 The Author(s).

  8. Inorganic Nitrogen Derived from Foraging Honey Bees Could Have Adaptive Benefits for the Plants They Visit

    PubMed Central

    Mishra, Archana; Afik, Ohad; Cabrera, Miguel L.; Delaplane, Keith S.; Mowrer, Jason E.

    2013-01-01

    In most terrestrial ecosystems, nitrogen (N) is the most limiting nutrient for plant growth. Honey bees may help alleviate this limitation because their feces (frass) have high concentration of organic nitrogen that may decompose in soil and provide inorganic N to plants. However, information on soil N processes associated with bee frass is not available. The objectives of this work were to 1) estimate the amount of bee frass produced by a honey bee colony and 2) evaluate nitrogen mineralization and ammonia volatilization from bee frass when surface applied or incorporated into soil. Two cage studies were conducted to estimate the amount of frass produced by a 5000-bee colony, and three laboratory studies were carried out in which bee frass, surface-applied or incorporated into soil, was incubated at 25oC for 15 to 45 days. The average rate of bee frass production by a 5,000-bee colony was estimated at 2.27 to 2.69 g N month−1. Nitrogen mineralization from bee frass during 30 days released 20% of the organic N when bee frass was surface applied and 34% when frass was incorporated into the soil. Volatilized NH3 corresponded to 1% or less of total N. The potential amount of inorganic N released to the soil by a typical colony of 20,000 bees foraging in an area similar to that of the experimental cages (3.24 m2) was estimated at 0.62 to 0.74 g N m−2 month−1 which may be significant at a community scale in terms of soil microbial activity and plant growth. Thus, the deposition of available N by foraging bees could have adaptive benefits for the plants they visit, a collateral benefit deriving from the primary activity of pollination. PMID:23923006

  9. Terrestrial sequestration

    SciTech Connect

    Charlie Byrer

    2008-03-10

    Terrestrial sequestration is the enhancement of CO2 uptake by plants that grow on land and in freshwater and, importantly, the enhancement of carbon storage in soils where it may remain more permanently stored. Terrestrial sequestration provides an opportunity for low-cost CO2 emissions offsets.

  10. Terrestrial sequestration

    ScienceCinema

    Charlie Byrer

    2016-07-12

    Terrestrial sequestration is the enhancement of CO2 uptake by plants that grow on land and in freshwater and, importantly, the enhancement of carbon storage in soils where it may remain more permanently stored. Terrestrial sequestration provides an opportunity for low-cost CO2 emissions offsets.

  11. Report Bee Kills

    EPA Pesticide Factsheets

    EPA uses incident report data to help inform our pesticide regulatory decisions. Information from these reports helps us identify patterns of bee kills associated with the use of specific pesticides or active ingredients. Here's how to report incidents.

  12. A Buzzing Bee.

    ERIC Educational Resources Information Center

    Donovan, Edward P.; Barnes, Eb

    1996-01-01

    Presents an activity enabling students of grades four to nine to construct a "Buzzing Bee" model using simple materials. Provides students with the opportunity to explore the concepts of sound and the Doppler effect. (MKR)

  13. A Buzzing Bee.

    ERIC Educational Resources Information Center

    Donovan, Edward P.; Barnes, Eb

    1996-01-01

    Presents an activity enabling students of grades four to nine to construct a "Buzzing Bee" model using simple materials. Provides students with the opportunity to explore the concepts of sound and the Doppler effect. (MKR)

  14. Consequences of toxic secondary compounds in nectar for mutualist bees and antagonist butterflies.

    PubMed

    Jones, Patricia L; Agrawal, Anurag A

    2016-10-01

    Attraction of mutualists and defense against antagonists are critical challenges for most organisms and can be especially acute for plants with pollinating and non-pollinating flower visitors. Secondary compounds in flowers have been hypothesized to adaptively mediate attraction of mutualists and defense against antagonists, but this hypothesis has rarely been tested. The tissues of milkweeds (Asclepias spp.) contain toxic cardenolides that have long been studied as chemical defenses against herbivores. Milkweed nectar also contains cardenolides, and we have examined the impact of manipulating cardenolides in nectar on the foraging choices of two flower visitors: generalist bumble bees, Bombus impatiens, which are mutualistic pollinators, and specialist monarch butterflies, Danaus plexippus, which are herbivores as larvae and ineffective pollinators as adults. Although individual bumble bees in single foraging bouts showed no avoidance of cardenolides at the highest natural concentrations reported for milkweeds, a pattern of deterrence did arise when entire colonies were allowed to forage for several days. Monarch butterflies were not deterred by the presence of cardenolides in nectar when foraging from flowers, but laid fewer eggs on plants paired with cardenolide-laced flowers compared to controls. Thus, although deterrence of bumble bees by cardenolides may only occur after extensive foraging, a primary effect of nectar cardenolides appears to be reduction of monarch butterfly oviposition. © 2016 by the Ecological Society of America.

  15. A simple model for pollen-parent fecundity distributions in bee-pollinated forage legume polycrosses.

    PubMed

    Riday, Heathcliffe; Smith, Mark A; Peel, Michael D

    2015-09-01

    A simple Weibull distribution based empirical model that predicts pollen-parent fecundity distributions based on polycross size alone has been developed in outbred forage legume species for incorporation into quantitative genetic theory. Random mating or panmixis is a fundamental assumption in quantitative genetic theory. Random mating is sometimes thought to occur in actual fact, although a large body of empirical work shows that this is often not the case in nature. Models have been developed to explain many non-random mating phenomena. This paper measured pollen-parent fecundity distributions among outbred perennial forage legume species [autotetraploid alfalfa (Medicago sativa L.), autohexaploid kura clover (Trifolium ambiguum M. Bieb.), and diploid red clover (Trifolium pratense L.)] in ten polycrosses ranging in size (N) from 9 to 94 pollinated with bee pollinators [Bumble Bees (Bombus impatiens Cr.) and leafcutter bees (Megachile rotundata F.)]. A Weibull distribution best fit the observed pollen-parent fecundity distributions. After standardizing data among the 10 polycrosses, a single Weibull distribution-based model was obtained with an R (2) of 0.978. The model is able to predict pollen-parent fecundity distributions based on polycross size alone. The model predicts that the effective polycross size will be approximately 9 % smaller than under random mating (i.e., N e/N ~ 0.91). The model is simple and can easily be incorporated into other models or simulations requiring a pollen-parent fecundity distribution. Further work is needed to determine how widely applicable the model is.

  16. Magnetic effect on dancing bees

    NASA Technical Reports Server (NTRS)

    Lindauer, M.; Martin, H.

    1972-01-01

    Bee sensitivity to the earth's magnetic field is studied. Data cover sensitivity range and the use of magnetoreception for orientation purposes. Experimental results indicate bee orientation is aided by gravity fields when the magnetic field is compensated.

  17. Stakeholder Conference on Bee Health

    EPA Pesticide Factsheets

    USDA and EPA released a comprehensive scientific report on honey bee health in May 2013. The report points to multiple factors playing a role in honey bee colony declines, including parasites and disease, genetics, poor nutrition, and pesticide exposure.

  18. Test of the invasive pathogen hypothesis of bumble bee decline in North America.

    PubMed

    Cameron, Sydney A; Lim, Haw Chuan; Lozier, Jeffrey D; Duennes, Michelle A; Thorp, Robbin

    2016-04-19

    Emergent fungal diseases are critical factors in global biodiversity declines. The fungal pathogenNosema bombiwas recently found to be widespread in declining species of North American bumble bees (Bombus), with circumstantial evidence suggesting an exotic introduction from Europe. This interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns ofN. bombiin declining North American populations. Thus, the temporal and spatial emergence ofN. bombiand its potential role in bumble bee decline remain speculative. We analyzeNosemaprevalence and genetic variation in the United States and Europe from 1980, before an alleged introduction in the early 1990s, to 2011, extractingNosemaDNA fromBombusnatural history collection specimens from across this time period.Nosema bombiprevalence increased significantly from low detectable frequency in the 1980s to significantly higher frequency in the mid- to late-1990s, corresponding to a period of reported massive infectious outbreak ofN. bombiin commercial bumble bee rearing stocks in North America. Despite the increased frequency, we find no conclusive evidence of an exoticN. bombiorigin based on genetic analysis of globalNosemapopulations; the widespreadNosemastrain found currently in declining United States bumble bees was present in the United States before commercial colony trade. Notably, the USN. bombiis not detectably different from that found predominantly throughout Western Europe, with both regions characterized by low genetic diversity compared with high levels of diversity found in Asia, where commercial bee breeding activities are low or nonexistent.

  19. Water homeostasis in bees, with the emphasis on sociality.

    PubMed

    Nicolson, Susan W

    2009-02-01

    Avenues of water gain and loss in bees are examined here at two levels of organisation: the individual and the colony. Compared with the majority of terrestrial insects, bees have a high water turnover. This is due to their nectar diet and, in larger species, substantial metabolic water production during flight, counteracted by high evaporative and excretory losses. Water fluxes at the colony level can also be very high. When incoming nectar is dilute, honeybees need to remove large volumes of water by evaporation. On the other hand, water is not stored in the nest and must be collected for evaporative cooling and for feeding the brood. Water regulation has many similarities at individual and colony levels. In particular, manipulation of nectar or water on the tongue is extensively used by bees to increase evaporation for either food-concentrating or cooling purposes.

  20. Bumble-bee foragers infected by a gut parasite have an impaired ability to utilize floral information

    PubMed Central

    Gegear, Robert J; Otterstatter, Michael C; Thomson, James D

    2006-01-01

    Parasitic infection can influence a variety of behavioural mechanisms in animals, but little is known about the effects of infection on the cognitive processes underlying ecologically relevant behaviours. Here, we examined whether parasitic infection alters cognitive aspects of foraging in a social insect, the bumble-bee (Bombus impatiens). In controlled experiments, we assessed the ability of foraging bees to discriminate rewarding from non-rewarding flowers on the basis of colour and odour. We found that natural and experimental infection by a protozoan parasite (Crithidia bombi, which lives exclusively within the gut tract), impaired the ability of foragers to learn the colour of rewarding flowers. Parasitic infection can thus disrupt central nervous system pathways that mediate cognitive processes in bumble-bees and as a consequence, can reduce their ability to monitor floral resources and make economic foraging decisions. It is postulated that this infection-induced change to cognitive function in bumble-bees is the result of communication between immune and nervous systems. Parasitized animals, including invertebrates, can therefore show subtle behavioural changes that are nonetheless ecologically significant and reflect complex mechanisms. PMID:16600883

  1. Recent Honey Bee Colony Declines

    DTIC Science & Technology

    2007-06-20

    sustain wildlife populations ; emphasizing the importance of pollinator diversity and sustaining wild and native pollinator species; developing or...Bee Population Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Recent Colony Losses from Available Surveys...www.masterbeekeeper.org/pdf/ pollination.pdf]. Source: Bee Alert Inc., [http://www.beealert.info/]. Shaded areas show reported affected states. Past Honey Bee Population

  2. Chalkbrood disease in honey bees

    USDA-ARS?s Scientific Manuscript database

    Chalkbrood is an invasive mycosis in honey bees (Apis mellifera L.) produced by Ascosphaera apis (Maassen ex Claussen) Olive and Spiltoir (Spiltoir, 1955) that exclusively affects bee brood. Although fatal to individual larvae, the disease does not usually destroy an entire bee colony. However, it c...

  3. Bee Line BR-1 Racer

    NASA Technical Reports Server (NTRS)

    1926-01-01

    Bee Line BR-1 Racer: The Bee Line BR-1 was a racing aircraft used to compete in the 1922 Pulitzer Air Race. The aircraft and its sister ship, the Bee Line BR-2, came to Langley and the NACA in 1926. The BR-1 is shown in the NACA hangar at Langley Field in early 1926.

  4. Honey Bees, Satellites and Climate Change

    NASA Astrophysics Data System (ADS)

    Esaias, W.

    2008-05-01

    Life isn't what it used to be for honey bees in Maryland. The latest changes in their world are discussed by NASA scientist Wayne Esaias, a biological oceanographer with NASA Goddard Space Flight Center. At Goddard, Esaias has examined the role of marine productivity in the global carbon cycle using visible satellite sensors. In his personal life, Esaias is a beekeeper. Lately, he has begun melding his interest in bees with his professional expertise in global climate change. Esaias has observed that the period when nectar is available in central Maryland has shifted by one month due to local climate change. He is interested in bringing the power of global satellite observations and models to bear on the important but difficult question of how climate change will impact bees and pollination. Pollination is a complex, ephemeral interaction of animals and plants with ramifications throughout terrestrial ecosystems well beyond the individual species directly involved. Pollinators have been shown to be in decline in many regions, and the nature and degree of further impacts on this key interaction due to climate change are very much open questions. Honey bee colonies are used to quantify the time of occurrence of the major interaction by monitoring their weight change. During the peak period, changes of 5-15 kg/day per colony represent an integrated response covering thousands of hectares. Volunteer observations provide a robust metric for looking at spatial and inter-annual variations due to short term climate events, complementing plant phenology networks and satellite-derived vegetation phenology data. In central Maryland, the nectar flows are advancing by about -0.6 d/y, based on a 15 yr time series and a small regional study. This is comparable to the regional advancement in the spring green-up observed with MODIS and AVHRR. The ability to link satellite vegetation phenology to honey bee forage using hive weight changes provides a basis for applying satellite

  5. Identification of candidate agents active against N. ceranae infection in honey bees: establishment of a medium throughput screening assay based on N. ceranae infected cultured cells.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Many flowering plants in both natural ecosytems and agriculture are dependent on insect pollination for fruit set and seed production. Managed honey bees (Apis mellifera) and wild bees are key pollinators providing this indispensable eco- and agrosystem service. Like all other organisms, bees are attacked by numerous pathogens and parasites. Nosema apis is a honey bee pathogenic microsporidium which is widely distributed in honey bee populations without causing much harm. Its congener Nosema ceranae was originally described as pathogen of the Eastern honey bee (Apis cerana) but jumped host from A. cerana to A. mellifera about 20 years ago and spilled over from A. mellifera to Bombus spp. quite recently. N. ceranae is now considered a deadly emerging parasite of both Western honey bees and bumblebees. Hence, novel and sustainable treatment strategies against N. ceranae are urgently needed to protect honey and wild bees. We here present the development of an in vitro medium throughput screening assay for the identification of candidate agents active against N. ceranae infections. This novel assay is based on our recently developed cell culture model for N. ceranae and coupled with an RT-PCR-ELISA protocol for quantification of N. ceranae in infected cells. The assay has been adapted to the 96-well microplate format to allow automated analysis. Several substances with known (fumagillin) or presumed (surfactin) or no (paromomycin) activity against N. ceranae were tested as well as substances for which no data concerning N. ceranae inhibition existed. While fumagillin and two nitroimidazoles (metronidazole, tinidazole) totally inhibited N. ceranae proliferation, all other test substances were inactive. In summary, the assay proved suitable for substance screening and demonstrated the activity of two synthetic antibiotics against N. ceranae.

  6. Identification of Candidate Agents Active against N. ceranae Infection in Honey Bees: Establishment of a Medium Throughput Screening Assay Based on N. ceranae Infected Cultured Cells

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Many flowering plants in both natural ecosytems and agriculture are dependent on insect pollination for fruit set and seed production. Managed honey bees (Apis mellifera) and wild bees are key pollinators providing this indispensable eco- and agrosystem service. Like all other organisms, bees are attacked by numerous pathogens and parasites. Nosema apis is a honey bee pathogenic microsporidium which is widely distributed in honey bee populations without causing much harm. Its congener Nosema ceranae was originally described as pathogen of the Eastern honey bee (Apis cerana) but jumped host from A. cerana to A. mellifera about 20 years ago and spilled over from A. mellifera to Bombus spp. quite recently. N. ceranae is now considered a deadly emerging parasite of both Western honey bees and bumblebees. Hence, novel and sustainable treatment strategies against N. ceranae are urgently needed to protect honey and wild bees. We here present the development of an in vitro medium throughput screening assay for the identification of candidate agents active against N. ceranae infections. This novel assay is based on our recently developed cell culture model for N. ceranae and coupled with an RT-PCR-ELISA protocol for quantification of N. ceranae in infected cells. The assay has been adapted to the 96-well microplate format to allow automated analysis. Several substances with known (fumagillin) or presumed (surfactin) or no (paromomycin) activity against N. ceranae were tested as well as substances for which no data concerning N. ceranae inhibition existed. While fumagillin and two nitroimidazoles (metronidazole, tinidazole) totally inhibited N. ceranae proliferation, all other test substances were inactive. In summary, the assay proved suitable for substance screening and demonstrated the activity of two synthetic antibiotics against N. ceranae. PMID:25658121

  7. [Bee, wax and honey].

    PubMed

    de Laguérenne, Claude

    2003-01-01

    The archives of Nantes contain two manuscripts of the XVIIth century from which we found 63 formulae which enter bees, honey and wax. Our study concerns these various galeniques forms for internal use or external used in therapeutics and in beauty care.

  8. TERRESTRIAL ECOTOXICOLOGY

    EPA Science Inventory

    Terrestrial ecotoxicology is the study of how environmental pollutants affect land-dependent organisms and their environment. It requires three elements: (1) a source, (2) a receptor, and (3) an exposure pathway. This article reviews the basic principles of each of each element...

  9. Impact of managed honey bee viruses on wild bees.

    PubMed

    Tehel, Anja; Brown, Mark Jf; Paxton, Robert J

    2016-08-01

    Several viruses found in the Western honey bee (Apis mellifera) have recently been detected in other bee species, raising the possibility of spill-over from managed to wild bee species. Alternatively, these viruses may be shared generalists across flower-visiting insects. Here we explore the former hypothesis, pointing out weaknesses in the current evidence, particularly in relation to deformed wing virus (DWV), and highlighting research areas that may help test it. Data so far suggest that DWV spills over from managed to wild bee species and has the potential to cause population decline. That DWV and other viruses of A. mellifera are found in other bee species needs to be considered for the sustainable management of bee populations. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Bees brought to their knees: microbes affecting honey bee health.

    PubMed

    Evans, Jay D; Schwarz, Ryan S

    2011-12-01

    The biology and health of the honey bee Apis mellifera has been of interest to human societies for centuries. Research on honey bee health is surging, in part due to new tools and the arrival of colony-collapse disorder (CCD), an unsolved decline in bees from parts of the United States, Europe, and Asia. Although a clear understanding of what causes CCD has yet to emerge, these efforts have led to new microbial discoveries and avenues to improve our understanding of bees and the challenges they face. Here we review the known honey bee microbes and highlight areas of both active and lagging research. Detailed studies of honey bee-pathogen dynamics will help efforts to keep this important pollinator healthy and will give general insights into both beneficial and harmful microbes confronting insect colonies. Copyright © 2011. Published by Elsevier Ltd.

  11. Segregation of visual inputs from different regions of the compound eye in two parallel pathways through the anterior optic tubercle of the bumblebee (Bombus ignitus).

    PubMed

    Pfeiffer, Keram; Kinoshita, Michiyo

    2012-02-01

    Visually guided behaviors require the brain to extract features of the visual world and to integrate them in a context-specific manner. Hymenopteran insects have been prime models for ethological research into visual behaviors for decades but knowledge about the underlying central processing is very limited. This is particularly the case for sky-compass navigation. To learn more about central processing of visual information in general and specifically to reveal a possible polarization vision pathway in the bee brain, we used tracer injections to investigate the pathways through the anterior optic tubercle, a prominent output target of the insect optic lobe, in the bumblebee Bombus ignitus. The anterior optic tubercle of the bumblebee is a small neuropil of 200 μm width and is located dorsolateral to the antennal lobe at the anterior surface of the brain. It is divided into a larger upper and a smaller lower subunit, both of which receive input from the optic lobe and connect to the lateral accessory lobe, and the contralateral tubercle, via two parallel pathways. The lower subunit receives input from the dorsal rim area (DRA) of the compound eye. The bumblebee DRA shares structural similarities with polarization-sensitive DRAs of other insects and looks similar to that of honeybees. We identified several neurons within this pathway that could be homologous to identified polarization-sensitive neurons in the locust brain. We therefore conclude that the pathway through the lower subunit of the anterior optic tubercle could carry polarization information from the periphery to the central brain.

  12. Red mason bees cannot compete with honey bees for floral resources in a cage experiment.

    PubMed

    Hudewenz, Anika; Klein, Alexandra-Maria

    2015-11-01

    Intensive beekeeping to mitigate crop pollination deficits and habitat loss may cause interspecific competition between bees. Studies show negative correlations between flower visitation of honey bees (Apis mellifera) and wild bees, but effects on the reproduction of wild bees were not proven. Likely reasons are that honey bees can hardly be excluded from controls and wild bee nests are generally difficult to detect in field experiments. The goal of this study was to investigate whether red mason bees (Osmia bicornis) compete with honey bees in cages in order to compare the reproduction of red mason bees under different honey bee densities. Three treatments were applied, each replicated in four cages of 18 m³ with 38 red mason bees in all treatments and 0, 100, and 300 honey bees per treatment with 10-20% being foragers. Within the cages, the flower visitation and interspecific displacements from flowers were observed. Niche breadths and resource overlaps of both bee species were calculated, and the reproduction of red mason bees was measured. Red mason bees visited fewer flowers when honey bees were present. Niche breadth of red mason bees decreased with increasing honey bee density while resource overlaps remained constant. The reproduction of red mason bees decreased in cages with honey bees. In conclusion, our experimental results show that in small and isolated flower patches, wild bees can temporarily suffer from competition with honey bees. Further research should aim to test for competition on small and isolated flower patches in real landscapes.

  13. Special Issue: Honey Bee Viruses.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-10-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field.

  14. Special Issue: Honey Bee Viruses

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  15. Intelligent Control for the BEES Flyer

    NASA Technical Reports Server (NTRS)

    Krishnakumar, K.; Gundy-Burlet, Karen; Aftosmis, Mike; Nemec, Marian; Limes, Greg; Berry, Misty; Logan, Michael

    2004-01-01

    This paper describes the effort to provide a preliminary capability analysis and a neural network based adaptive flight control system for the JPL-led BEES aircraft project. The BEES flyer was envisioned to be a small, autonomous platform with sensing and control systems mimicking those of biological systems for the purpose of scientific exploration on the surface of Mars. The platform is physically tightly constrained by the necessity of efficient packing within rockets for the trip to Mars. Given the physical constraints, the system is not an ideal configuration for aerodynamics or stability and control. The objectives of this effort are to evaluate the aerodynamics characteristics of the existing design, to make recommendaaons as to potential improvements and to provide a control system that stabilizes the existing aircraft for nominal flight and damaged conditions. Towards this several questions are raised and analyses are presented to arrive at answers to some of the questions raised. CART3D, a high-fidelity inviscid analysis package for conceptual and preliminary aerodynamic design, was used to compute a parametric set of solutions over the expected flight domain. Stability and control derivatives were extracted from the database and integrated with the neural flight control system. The Integrated Vehicle Modeling Environment (IVME) was also used for estimating aircraft geometric, inertial, and aerodynamic characteristics. A generic neural flight control system is used to provide adaptive control without the requirement for extensive gain scheduling or explicit system identification. The neural flight control system uses reference models to specify desired handling qualities in the roll, pitch, and yaw axes, and incorporates both pre-trained and on-line learning neural networks in the inverse model portion of the controller. Results are presented for the BEES aircraft in the subsonic regime for terrestrial and Martian environments.

  16. Honey Bee Colonies Remote Monitoring System.

    PubMed

    Gil-Lebrero, Sergio; Quiles-Latorre, Francisco Javier; Ortiz-López, Manuel; Sánchez-Ruiz, Víctor; Gámiz-López, Victoria; Luna-Rodríguez, Juan Jesús

    2016-12-29

    Bees are very important for terrestrial ecosystems and, above all, for the subsistence of many crops, due to their ability to pollinate flowers. Currently, the honey bee populations are decreasing due to colony collapse disorder (CCD). The reasons for CCD are not fully known, and as a result, it is essential to obtain all possible information on the environmental conditions surrounding the beehives. On the other hand, it is important to carry out such information gathering as non-intrusively as possible to avoid modifying the bees' work conditions and to obtain more reliable data. We designed a wireless-sensor networks meet these requirements. We designed a remote monitoring system (called WBee) based on a hierarchical three-level model formed by the wireless node, a local data server, and a cloud data server. WBee is a low-cost, fully scalable, easily deployable system with regard to the number and types of sensors and the number of hives and their geographical distribution. WBee saves the data in each of the levels if there are failures in communication. In addition, the nodes include a backup battery, which allows for further data acquisition and storage in the event of a power outage. Unlike other systems that monitor a single point of a hive, the system we present monitors and stores the temperature and relative humidity of the beehive in three different spots. Additionally, the hive is continuously weighed on a weighing scale. Real-time weight measurement is an innovation in wireless beehive-monitoring systems. We designed an adaptation board to facilitate the connection of the sensors to the node. Through the Internet, researchers and beekeepers can access the cloud data server to find out the condition of their hives in real time.

  17. Testing Dose-Dependent Effects of the Nectar Alkaloid Anabasine on Trypanosome Parasite Loads in Adult Bumble Bees

    PubMed Central

    Anthony, Winston E.; Palmer-Young, Evan C.; Leonard, Anne S.; Irwin, Rebecca E.; Adler, Lynn S.

    2015-01-01

    The impact of consuming biologically active compounds is often dose-dependent, where small quantities can be medicinal while larger doses are toxic. The consumption of plant secondary compounds can be toxic to herbivores in large doses, but can also improve survival in parasitized herbivores. In addition, recent studies have found that consuming nectar secondary compounds may decrease parasite loads in pollinators. However, the effect of compound dose on bee survival and parasite loads has not been assessed. To determine how secondary compound consumption affects survival and pathogen load in Bombus impatiens, we manipulated the presence of a common gut parasite, Crithidia bombi, and dietary concentration of anabasine, a nectar alkaloid produced by Nicotiana spp. using four concentrations naturally observed in floral nectar. We hypothesized that increased consumption of secondary compounds at concentrations found in nature would decrease survival of uninfected bees, but improve survival and ameliorate parasite loads in infected bees. We found medicinal effects of anabasine in infected bees; the high-anabasine diet decreased parasite loads and increased the probability of clearing the infection entirely. However, survival time was not affected by any level of anabasine concentration, or by interactive effects of anabasine concentration and infection. Crithidia infection reduced survival time by more than two days, but this effect was not significant. Our results support a medicinal role for anabasine at the highest concentration; moreover, we found no evidence for a survival-related cost of anabasine consumption across the concentration range found in nectar. Our results suggest that consuming anabasine at the higher levels of the natural range could reduce or clear pathogen loads without incurring costs for healthy bees. PMID:26545106

  18. Testing Dose-Dependent Effects of the Nectar Alkaloid Anabasine on Trypanosome Parasite Loads in Adult Bumble Bees.

    PubMed

    Anthony, Winston E; Palmer-Young, Evan C; Leonard, Anne S; Irwin, Rebecca E; Adler, Lynn S

    2015-01-01

    The impact of consuming biologically active compounds is often dose-dependent, where small quantities can be medicinal while larger doses are toxic. The consumption of plant secondary compounds can be toxic to herbivores in large doses, but can also improve survival in parasitized herbivores. In addition, recent studies have found that consuming nectar secondary compounds may decrease parasite loads in pollinators. However, the effect of compound dose on bee survival and parasite loads has not been assessed. To determine how secondary compound consumption affects survival and pathogen load in Bombus impatiens, we manipulated the presence of a common gut parasite, Crithidia bombi, and dietary concentration of anabasine, a nectar alkaloid produced by Nicotiana spp. using four concentrations naturally observed in floral nectar. We hypothesized that increased consumption of secondary compounds at concentrations found in nature would decrease survival of uninfected bees, but improve survival and ameliorate parasite loads in infected bees. We found medicinal effects of anabasine in infected bees; the high-anabasine diet decreased parasite loads and increased the probability of clearing the infection entirely. However, survival time was not affected by any level of anabasine concentration, or by interactive effects of anabasine concentration and infection. Crithidia infection reduced survival time by more than two days, but this effect was not significant. Our results support a medicinal role for anabasine at the highest concentration; moreover, we found no evidence for a survival-related cost of anabasine consumption across the concentration range found in nectar. Our results suggest that consuming anabasine at the higher levels of the natural range could reduce or clear pathogen loads without incurring costs for healthy bees.

  19. A field study examining the effects of exposure to neonicotinoid seed-treated corn on commercial bumble bee colonies.

    PubMed

    Christopher Cutler, G; Scott-Dupree, Cynthia D

    2014-11-01

    Neonicotinoid insecticides have been studied as possible contributors to bumble bee declines in North America and Europe. This has potential significance in corn agro-ecosystems since this crop is frequently treated with neonicotinoids and dominates much of the agricultural landscape in North America and Europe where bumble bees and other pollinators are commonplace. We conducted an experiment where commercial bumble bee (Bombus impatiens) hives were placed during pollen shed next to corn (Zea mays) fields that were grown from "conventional" seed that was treated with neonicotinoids, or "organic" seed that was not treated with pesticides. Samples of pollen were collected from corn plants for neonicotinoid residue analysis, pollen types carried by worker bees returning to hives were determined, and in autumn hives were dissected to measure various endpoints that serve as markers of colony vigor. Clothianidin was detected (0.1-0.8 ng/g) in pollen collected from all conventional fields, but was not detected in pollen from organic fields. Corn pollen was only rarely collected from bumble bee foragers and the vast majority of pollen was from wild plants around the corn fields. All hives appeared healthy and neonicotinoid seed treatments had no effect on any hive endpoints measured, except the number of workers, where significantly fewer workers were recovered from hives placed next to conventional fields (96 ± 15 workers per hive) compared to organic fields (127 ± 17 workers per hive). The results suggest that exposure during pollen shed to corn grown from neonicotinoid-treated shed poses low risk to B. impatiens.

  20. Bees brought to their knees: Microbes affecting honey bee health

    USDA-ARS?s Scientific Manuscript database

    The biology and health of the honey bee, Apis mellifera, has been of interest to human societies since the advent of beekeeping. Descriptive scientific research on pathogens affecting honey bees have been published for nearly a century, but it wasn’t until the recent outbreak of heavy colony losses...

  1. Extracting the Behaviorally Relevant Stimulus: Unique Neural Representation of Farnesol, a Component of the Recruitment Pheromone of Bombus terrestris.

    PubMed

    Strube-Bloss, Martin F; Brown, Austin; Spaethe, Johannes; Schmitt, Thomas; Rössler, Wolfgang

    2015-01-01

    To trigger innate behavior, sensory neural networks are pre-tuned to extract biologically relevant stimuli. Many male-female or insect-plant interactions depend on this phenomenon. Especially communication among individuals within social groups depends on innate behaviors. One example is the efficient recruitment of nest mates by successful bumblebee foragers. Returning foragers release a recruitment pheromone in the nest while they perform a 'dance' behavior to activate unemployed nest mates. A major component of this pheromone is the sesquiterpenoid farnesol. How farnesol is processed and perceived by the olfactory system, has not yet been identified. It is much likely that processing farnesol involves an innate mechanism for the extraction of relevant information to trigger a fast and reliable behavioral response. To test this hypothesis, we used population response analyses of 100 antennal lobe (AL) neurons recorded in alive bumblebee workers under repeated stimulation with four behaviorally different, but chemically related odorants (geraniol, citronellol, citronellal and farnesol). The analysis identified a unique neural representation of the recruitment pheromone component compared to the other odorants that are predominantly emitted by flowers. The farnesol induced population activity in the AL allowed a reliable separation of farnesol from all other chemically related odor stimuli we tested. We conclude that the farnesol induced population activity may reflect a predetermined representation within the AL-neural network allowing efficient and fast extraction of a behaviorally relevant stimulus. Furthermore, the results show that population response analyses of multiple single AL-units may provide a powerful tool to identify distinct representations of behaviorally relevant odors.

  2. Extracting the Behaviorally Relevant Stimulus: Unique Neural Representation of Farnesol, a Component of the Recruitment Pheromone of Bombus terrestris

    PubMed Central

    Strube-Bloss, Martin F.; Brown, Austin; Spaethe, Johannes; Schmitt, Thomas; Rössler, Wolfgang

    2015-01-01

    To trigger innate behavior, sensory neural networks are pre-tuned to extract biologically relevant stimuli. Many male-female or insect-plant interactions depend on this phenomenon. Especially communication among individuals within social groups depends on innate behaviors. One example is the efficient recruitment of nest mates by successful bumblebee foragers. Returning foragers release a recruitment pheromone in the nest while they perform a ‘dance’ behavior to activate unemployed nest mates. A major component of this pheromone is the sesquiterpenoid farnesol. How farnesol is processed and perceived by the olfactory system, has not yet been identified. It is much likely that processing farnesol involves an innate mechanism for the extraction of relevant information to trigger a fast and reliable behavioral response. To test this hypothesis, we used population response analyses of 100 antennal lobe (AL) neurons recorded in alive bumblebee workers under repeated stimulation with four behaviorally different, but chemically related odorants (geraniol, citronellol, citronellal and farnesol). The analysis identified a unique neural representation of the recruitment pheromone component compared to the other odorants that are predominantly emitted by flowers. The farnesol induced population activity in the AL allowed a reliable separation of farnesol from all other chemically related odor stimuli we tested. We conclude that the farnesol induced population activity may reflect a predetermined representation within the AL-neural network allowing efficient and fast extraction of a behaviorally relevant stimulus. Furthermore, the results show that population response analyses of multiple single AL-units may provide a powerful tool to identify distinct representations of behaviorally relevant odors. PMID:26340263

  3. Succession influences wild bees in a temperate forest landscape: the value of early successional stages in naturally regenerated and planted forests.

    PubMed

    Taki, Hisatomo; Okochi, Isamu; Okabe, Kimiko; Inoue, Takenari; Goto, Hideaki; Matsumura, Takeshi; Makino, Shun'ichi

    2013-01-01

    In many temperate terrestrial forest ecosystems, both natural human disturbances drive the reestablishment of forests. Succession in plant communities, in addition to reforestation following the creation of open sites through harvesting or natural disturbances, can affect forest faunal assemblages. Wild bees perform an important ecosystem function in human-altered and natural or seminatural ecosystems, as they are essential pollinators for both crops and wild flowering plants. To maintain high abundance and species richness for pollination services, it is important to conserve and create seminatural and natural land cover with optimal successional stages for wild bees. We examined the effects of forest succession on wild bees. In particular, we evaluated the importance of early successional stages for bees, which has been suspected but not previously demonstrated. A range of successional stages, between 1 and 178 years old, were examined in naturally regenerated and planted forests. In total 4465 wild bee individuals, representing 113 species, were captured. Results for total bees, solitary bees, and cleptoparasitic bees in both naturally regenerated and planted conifer forests indicated a higher abundance and species richness in the early successional stages. However, higher abundance and species richness of social bees in naturally regenerated forest were observed as the successional stages progressed, whereas the abundance of social bees in conifer planted forest showed a concave-shaped relationship when plotted. The results suggest that early successional stages of both naturally regenerated and conifer planted forest maintain a high abundance and species richness of solitary bees and their cleptoparasitic bees, although social bees respond differently in the early successional stages. This may imply that, in some cases, active forest stand management policies, such as the clear-cutting of planted forests for timber production, would create early successional

  4. Recent Honey Bee Colony Declines

    DTIC Science & Technology

    2007-03-26

    Population Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Symptoms of Colony Collapse Disorder...MAAREC), which represents beekeeping associations in New Jersey, Maryland, Delaware, Pennsylvania, and West Virginia. Past Honey Bee Population Losses... population losses due to bee pests, parasites, pathogens, and disease. Most notable are declines due to two parasitic mites, the Varroa destructor and the

  5. Safety with Wasps and Bees.

    ERIC Educational Resources Information Center

    Hackett, Erla

    This guide is designed to provide elementary school teachers with safe learning activities concerning bees and wasps. The following topics are included: (1) the importance of a positive teacher attitude towards bees and wasps; (2) special problems posed by paper wasps; (3) what to do when a child is bothered by a wasp; (4) what to do if a wasp…

  6. Safety with Wasps and Bees.

    ERIC Educational Resources Information Center

    Hackett, Erla

    This guide is designed to provide elementary school teachers with safe learning activities concerning bees and wasps. The following topics are included: (1) the importance of a positive teacher attitude towards bees and wasps; (2) special problems posed by paper wasps; (3) what to do when a child is bothered by a wasp; (4) what to do if a wasp…

  7. Native bees and plant pollination

    USGS Publications Warehouse

    Ginsberg, H.S.

    2004-01-01

    Bees are important pollinators, but evidence suggests that numbers of some species are declining. Decreases have been documented in the honey bee, Apis mellifera (which was introduced to North America), but there are no monitoring programs for the vast majority of native species, so we cannot be sure about the extent of this problem. Recent efforts to develop standardized protocols for bee sampling will help us collect the data needed to assess trends in bee populations. Unfortunately, diversity of bee life cycles and phenologies, and the large number of rare species, make it difficult to assess trends in bee faunas. Changes in bee populations can affect plant reproduction, which can influence plant population density and cover, thus potentially modifying horizontal and vertical structure of a community, microclimate near the ground, patterns of nitrogen deposition, etc. These potential effects of changes in pollination patterns have not been assessed in natural communities. Effects of management actions on bees and other pollinators should be considered in conservation planning.

  8. Honey Bees: Sweetness and Mites

    USDA-ARS?s Scientific Manuscript database

    Honey bee colony losses have been in the news lately and the potential reasons for these losses have taken up much space in the news media. In order to clarify what role mites play in the current loss (2006-2007) of bee colonies, called Colony Collapse Disorder, a better understanding of what a mit...

  9. Genetic toolkits for bee health

    USDA-ARS?s Scientific Manuscript database

    Beekeepers, inspectors, and researchers have a shared interest in checking bees and hives for clues related to bee health and disease. These checks take many forms, from lifting fall supers prior to feeding decisions to carrying out sticky board or jar tests for estimating varroa populations. Most d...

  10. 7 CFR 322.29 - Dead bees.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Dead bees. 322.29 Section 322.29 Agriculture..., DEPARTMENT OF AGRICULTURE BEES, BEEKEEPING BYPRODUCTS, AND BEEKEEPING EQUIPMENT Importation and Transit of Restricted Articles § 322.29 Dead bees. (a) Dead bees imported into or transiting the United States must...

  11. 7 CFR 322.29 - Dead bees.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Dead bees. 322.29 Section 322.29 Agriculture..., DEPARTMENT OF AGRICULTURE BEES, BEEKEEPING BYPRODUCTS, AND BEEKEEPING EQUIPMENT Importation and Transit of Restricted Articles § 322.29 Dead bees. (a) Dead bees imported into or transiting the United States must...

  12. 7 CFR 322.29 - Dead bees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Dead bees. 322.29 Section 322.29 Agriculture..., DEPARTMENT OF AGRICULTURE BEES, BEEKEEPING BYPRODUCTS, AND BEEKEEPING EQUIPMENT Importation and Transit of Restricted Articles § 322.29 Dead bees. (a) Dead bees imported into or transiting the United States must...

  13. 7 CFR 322.29 - Dead bees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Dead bees. 322.29 Section 322.29 Agriculture..., DEPARTMENT OF AGRICULTURE BEES, BEEKEEPING BYPRODUCTS, AND BEEKEEPING EQUIPMENT Importation and Transit of Restricted Articles § 322.29 Dead bees. (a) Dead bees imported into or transiting the United States must...

  14. 7 CFR 322.29 - Dead bees.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Dead bees. 322.29 Section 322.29 Agriculture..., DEPARTMENT OF AGRICULTURE BEES, BEEKEEPING BYPRODUCTS, AND BEEKEEPING EQUIPMENT Importation and Transit of Restricted Articles § 322.29 Dead bees. (a) Dead bees imported into or transiting the United States must...

  15. Polychlorinated biphenyls in honey bees

    SciTech Connect

    Morse, R.A.; Culliney, T.W.; Gutenmann, W.H.; Littman, C.B.; Lisk, D.J.

    1987-02-01

    Honey bees (Apis mellifera L.) may traverse a radius of several miles from their hives and contact innumerable surfaces during their collection of nectar, pollen, propolis and water. In the process, they may become contaminated with surface constituents which are indicative of the type of environmental pollution in their particular foraging area. Honey has also been analyzed as a possible indicator of heavy metal pollution. Insecticides used in the vicinity of bee hives have been found in bees and honey. It has been recently reported that appreciable concentrations of polychlorinated biphenyls (PCBs) have been found in honey bees sampled throughout Connecticut. In the work reported here, an analytical survey was conducted on PCBs in honey bees, honey, propolis and related samples in several states to learn the extent of contamination and possible sources.

  16. Honey bee pathology: current threats to honey bees and beekeeping.

    PubMed

    Genersch, Elke

    2010-06-01

    Managed honey bees are the most important commercial pollinators of those crops which depend on animal pollination for reproduction and which account for 35% of the global food production. Hence, they are vital for an economic, sustainable agriculture and for food security. In addition, honey bees also pollinate a variety of wild flowers and, therefore, contribute to the biodiversity of many ecosystems. Honey and other hive products are, at least economically and ecologically rather, by-products of beekeeping. Due to this outstanding role of honey bees, severe and inexplicable honey bee colony losses, which have been reported recently to be steadily increasing, have attracted much attention and stimulated many research activities. Although the phenomenon "decline of honey bees" is far from being finally solved, consensus exists that pests and pathogens are the single most important cause of otherwise inexplicable colony losses. This review will focus on selected bee pathogens and parasites which have been demonstrated to be involved in colony losses in different regions of the world and which, therefore, are considered current threats to honey bees and beekeeping.

  17. [Bee mite: Varroa jacobsoni qudemans].

    PubMed

    Ozer, N; Boşgelmez, A

    1983-07-01

    Varroatosis caused by varroa jacobsoni on honeybee, Apis mellifera L., is currently one of the worlds major bee keeping problems. The mite parasites the adult honey bee, as well as its developmental stages, by sucking the insects's haemolymph. Up to date, many chemicals were used against this mite but still there is no chemical which has 100% effect and at the same time bees and their brood demonstrate a good tolerance. The investigations on biology and therapy on Varroa are still going on in many countries.

  18. Eumelanin and pheomelanin are predominant pigments in bumblebee (Apidae: Bombus) pubescence.

    PubMed

    Polidori, Carlo; Jorge, Alberto; Ornosa, Concepción

    2017-01-01

    Bumblebees (Hymenoptera: Apidae: Bombus) are well known for their important inter- and intra-specific variation in hair (or pubescence) color patterns, but the chemical nature of the pigments associated with these patterns is not fully understood. For example, though melanization is believed to provide darker colors, it still unknown which types of melanin are responsible for each color, and no conclusive data are available for the lighter colors, including white. By using dispersive Raman spectroscopy analysis on 12 species/subspecies of bumblebees from seven subgenera, we tested the hypothesis that eumelanin and pheomelanin, the two main melanin types occurring in animals, are largely responsible for bumblebee pubescence coloration. Eumelanin and pheomelanin occur in bumblebee pubescence. Black pigmentation is due to prevalent eumelanin, with visible signals of additional pheomelanin, while the yellow, orange, red and brown hairs clearly include pheomelanin. On the other hand, white hairs reward very weak Raman signals, suggesting that they are depigmented. Additional non-melanic pigments in yellow hair cannot be excluded but need other techniques to be detected. Raman spectra were more similar across similarly colored hairs, with no apparent effect of phylogeny and both melanin types appeared to be already used at the beginning of bumblebee radiation. We suggest that the two main melanin forms, at variable amounts and/or vibrational states, are sufficient in giving almost the whole color range of bumblebee pubescence, allowing these insects to use a single precursor instead of synthesizing a variety of chemically different pigments. This would agree with commonly seen color interchanges between body segments across Bombus species.

  19. Eumelanin and pheomelanin are predominant pigments in bumblebee (Apidae: Bombus) pubescence

    PubMed Central

    Jorge, Alberto; Ornosa, Concepción

    2017-01-01

    Background Bumblebees (Hymenoptera: Apidae: Bombus) are well known for their important inter- and intra-specific variation in hair (or pubescence) color patterns, but the chemical nature of the pigments associated with these patterns is not fully understood. For example, though melanization is believed to provide darker colors, it still unknown which types of melanin are responsible for each color, and no conclusive data are available for the lighter colors, including white. Methods By using dispersive Raman spectroscopy analysis on 12 species/subspecies of bumblebees from seven subgenera, we tested the hypothesis that eumelanin and pheomelanin, the two main melanin types occurring in animals, are largely responsible for bumblebee pubescence coloration. Results Eumelanin and pheomelanin occur in bumblebee pubescence. Black pigmentation is due to prevalent eumelanin, with visible signals of additional pheomelanin, while the yellow, orange, red and brown hairs clearly include pheomelanin. On the other hand, white hairs reward very weak Raman signals, suggesting that they are depigmented. Additional non-melanic pigments in yellow hair cannot be excluded but need other techniques to be detected. Raman spectra were more similar across similarly colored hairs, with no apparent effect of phylogeny and both melanin types appeared to be already used at the beginning of bumblebee radiation. Discussion We suggest that the two main melanin forms, at variable amounts and/or vibrational states, are sufficient in giving almost the whole color range of bumblebee pubescence, allowing these insects to use a single precursor instead of synthesizing a variety of chemically different pigments. This would agree with commonly seen color interchanges between body segments across Bombus species. PMID:28560094

  20. Do managed bees drive parasite spread and emergence in wild bees?

    PubMed

    Graystock, Peter; Blane, Edward J; McFrederick, Quinn S; Goulson, Dave; Hughes, William O H

    2016-04-01

    Bees have been managed and utilised for honey production for centuries and, more recently, pollination services. Since the mid 20th Century, the use and production of managed bees has intensified with hundreds of thousands of hives being moved across countries and around the globe on an annual basis. However, the introduction of unnaturally high densities of bees to areas could have adverse effects. Importation and deployment of managed honey bee and bumblebees may be responsible for parasite introductions or a change in the dynamics of native parasites that ultimately increases disease prevalence in wild bees. Here we review the domestication and deployment of managed bees and explain the evidence for the role of managed bees in causing adverse effects on the health of wild bees. Correlations with the use of managed bees and decreases in wild bee health from territories across the globe are discussed along with suggestions to mitigate further health reductions in wild bees.

  1. Honey Bee Viruses in Wild Bees: Viral Prevalence, Loads, and Experimental Inoculation.

    PubMed

    Dolezal, Adam G; Hendrix, Stephen D; Scavo, Nicole A; Carrillo-Tripp, Jimena; Harris, Mary A; Wheelock, M Joseph; O'Neal, Matthew E; Toth, Amy L

    2016-01-01

    Evidence of inter-species pathogen transmission from managed to wild bees has sparked concern that emerging diseases could be causing or exacerbating wild bee declines. While some pathogens, like RNA viruses, have been found in pollen and wild bees, the threat these viruses pose to wild bees is largely unknown. Here, we tested 169 bees, representing 4 families and 8 genera, for five common honey bee (Apis mellifera) viruses, finding that more than 80% of wild bees harbored at least one virus. We also quantified virus titers in these bees, providing, for the first time, an assessment of viral load in a broad spectrum of wild bees. Although virus detection was very common, virus levels in the wild bees were minimal-similar to or lower than foraging honey bees and substantially lower than honey bees collected from hives. Furthermore, when we experimentally inoculated adults of two different bee species (Megachile rotundata and Colletes inaequalis) with a mixture of common viruses that is lethal to honey bees, we saw no effect on short term survival. Overall, we found that honey bee RNA viruses can be commonly detected at low levels in many wild bee species, but we found no evidence that these pathogens cause elevated short-term mortality effects. However, more work on these viruses is greatly needed to assess effects on additional bee species and life stages.

  2. Characteristics of honey bee and non-Apis bee (Hymenoptera) farms in Canada.

    PubMed

    Daly, Z; Melhim, A; Weersink, A

    2012-08-01

    Here, we present a farm-level, Canada-wide analysis of Canadian bee farms in 2006; this article is the first report to distinguish between honey bee (Apis mellifera L.) farms and non-Apis bee (Hymenoptera) farms. Farms are characterized according to bee species, bee stocks, and whether the farm makes 50% or more of gross sales from bee-related activities. Farm characteristics, including bee stocks, gross sales, capital investments, land base, specialization, location, and operator demographics, are reported for the different farm types and sizes. Non-Apis bee farms are revealed to be a nontrivial part of the Canadian bee industry: 21.2% of Canadian bee farms have non-Apis bees and 16.6% have exclusively non-Apis bees. Important differences between honey bee farms and non-Apis bee farms also are found. These differences include the more land-intensive nature of non-Apis bee farms and the finding that non-Apis bee farms have greater diversity in terms of their primary commodity, even at higher bee stock levels.

  3. Honey Bee Viruses in Wild Bees: Viral Prevalence, Loads, and Experimental Inoculation

    PubMed Central

    Dolezal, Adam G.; Hendrix, Stephen D.; Scavo, Nicole A.; Carrillo-Tripp, Jimena; Harris, Mary A.; Wheelock, M. Joseph; O’Neal, Matthew E.; Toth, Amy L.

    2016-01-01

    Evidence of inter-species pathogen transmission from managed to wild bees has sparked concern that emerging diseases could be causing or exacerbating wild bee declines. While some pathogens, like RNA viruses, have been found in pollen and wild bees, the threat these viruses pose to wild bees is largely unknown. Here, we tested 169 bees, representing 4 families and 8 genera, for five common honey bee (Apis mellifera) viruses, finding that more than 80% of wild bees harbored at least one virus. We also quantified virus titers in these bees, providing, for the first time, an assessment of viral load in a broad spectrum of wild bees. Although virus detection was very common, virus levels in the wild bees were minimal—similar to or lower than foraging honey bees and substantially lower than honey bees collected from hives. Furthermore, when we experimentally inoculated adults of two different bee species (Megachile rotundata and Colletes inaequalis) with a mixture of common viruses that is lethal to honey bees, we saw no effect on short term survival. Overall, we found that honey bee RNA viruses can be commonly detected at low levels in many wild bee species, but we found no evidence that these pathogens cause elevated short-term mortality effects. However, more work on these viruses is greatly needed to assess effects on additional bee species and life stages. PMID:27832169

  4. Hey! A Bee Stung Me!

    MedlinePlus

    ... bees build nests out of wax in old trees and manmade hives (like the ones that beekeepers ... they build papery nests shaped like footballs in trees and shrubs. Yellowjackets have yellow and black stripes ...

  5. Competitive interactions between neotropical pollinators and africanized honey bees.

    PubMed

    Roubik, D W

    1978-09-15

    The Africanized honey bee, a hybrid of European and African honey bees, is thought to displace native pollinators. After experimental introduction of Africanized honey bee hives near flowers, stingless bees became less abundant or harvested-less resource as visitation by Africanized honey bees increased. Shifts in resource use caused by colonizing Africanized honey bees may lead to population decline of Neotropical pollinators.

  6. Polarimetric applications to identify bee honey

    NASA Astrophysics Data System (ADS)

    Espinosa-Luna, Rafael; Saucedo-Orozco, Izcoatl; Santiago-Lona, Cynthia V.; Franco-Sánchez, Juan M.; Magallanes-Luján, Alejandro

    2011-10-01

    A polarimetric characterization, consisting of the Mueller matrix determination and the measurement of the refractive index, is employed to study bee honey and corn syrup differences. Two samples of commercial marks of bee honey and one sample of commercial mark corn syrup are studied. Results show the corn syrup and one of the bee honey samples have a similar polarimetric behavior, which differs from the second bee honey sample. This behavior can be employed as a simple, qualitative test, to discriminate true bee honey from corn syrup or from adulterated bee honey.s-powe

  7. Seasonal cycles, phylogenetic assembly, and functional diversity of orchid bee communities

    PubMed Central

    Ramírez, Santiago R; Hernández, Carlos; Link, Andres; López-Uribe, Margarita M

    2015-01-01

    Neotropical rainforests sustain some of the most diverse terrestrial communities on Earth. Euglossine (or orchid) bees are a diverse lineage of insect pollinators distributed throughout the American tropics, where they provide pollination services to a staggering diversity of flowering plant taxa. Elucidating the seasonal patterns of phylogenetic assembly and functional trait diversity of bee communities can shed new light into the mechanisms that govern the assembly of bee pollinator communities and the potential effects of declining bee populations. Male euglossine bees collect, store, and accumulate odoriferous compounds (perfumes) to subsequently use during courtship display. Thus, synthetic chemical baits can be used to attract and monitor euglossine bee populations. We conducted monthly censuses of orchid bees in three sites in the Magdalena valley of Colombia – a region where Central and South American biotas converge – to investigate the structure, diversity, and assembly of euglossine bee communities through time in relation to seasonal climatic cycles. In particular, we tested the hypothesis that phylogenetic community structure and functional trait diversity changed in response to seasonal rainfall fluctuations. All communities exhibited strong to moderate phylogenetic clustering throughout the year, with few pronounced bursts of phylogenetic overdispersion that coincided with the transition from wet-to-dry seasons. Despite the heterogeneous distribution of functional traits (e.g., body size, body mass, and proboscis length) and the observed seasonal fluctuations in phylogenetic diversity, we found that functional trait diversity, evenness, and divergence remained constant during all seasons in all communities. However, similar to the pattern observed with phylogenetic diversity, functional trait richness fluctuated markedly with rainfall in all sites. These results emphasize the importance of considering seasonal fluctuations in community assembly

  8. Seasonal cycles, phylogenetic assembly, and functional diversity of orchid bee communities.

    PubMed

    Ramírez, Santiago R; Hernández, Carlos; Link, Andres; López-Uribe, Margarita M

    2015-05-01

    Neotropical rainforests sustain some of the most diverse terrestrial communities on Earth. Euglossine (or orchid) bees are a diverse lineage of insect pollinators distributed throughout the American tropics, where they provide pollination services to a staggering diversity of flowering plant taxa. Elucidating the seasonal patterns of phylogenetic assembly and functional trait diversity of bee communities can shed new light into the mechanisms that govern the assembly of bee pollinator communities and the potential effects of declining bee populations. Male euglossine bees collect, store, and accumulate odoriferous compounds (perfumes) to subsequently use during courtship display. Thus, synthetic chemical baits can be used to attract and monitor euglossine bee populations. We conducted monthly censuses of orchid bees in three sites in the Magdalena valley of Colombia - a region where Central and South American biotas converge - to investigate the structure, diversity, and assembly of euglossine bee communities through time in relation to seasonal climatic cycles. In particular, we tested the hypothesis that phylogenetic community structure and functional trait diversity changed in response to seasonal rainfall fluctuations. All communities exhibited strong to moderate phylogenetic clustering throughout the year, with few pronounced bursts of phylogenetic overdispersion that coincided with the transition from wet-to-dry seasons. Despite the heterogeneous distribution of functional traits (e.g., body size, body mass, and proboscis length) and the observed seasonal fluctuations in phylogenetic diversity, we found that functional trait diversity, evenness, and divergence remained constant during all seasons in all communities. However, similar to the pattern observed with phylogenetic diversity, functional trait richness fluctuated markedly with rainfall in all sites. These results emphasize the importance of considering seasonal fluctuations in community assembly and

  9. Phylogenomic Insights into the Evolution of Stinging Wasps and the Origins of Ants and Bees.

    PubMed

    Branstetter, Michael G; Danforth, Bryan N; Pitts, James P; Faircloth, Brant C; Ward, Philip S; Buffington, Matthew L; Gates, Michael W; Kula, Robert R; Brady, Seán G

    2017-04-03

    The stinging wasps (Hymenoptera: Aculeata) are an extremely diverse lineage of hymenopteran insects, encompassing over 70,000 described species and a diversity of life history traits, including ectoparasitism, cleptoparasitism, predation, pollen feeding (bees [Anthophila] and Masarinae), and eusociality (social vespid wasps, ants, and some bees) [1]. The most well-studied lineages of Aculeata are the ants, which are ecologically dominant in most terrestrial ecosystems [2], and the bees, the most important lineage of angiosperm-pollinating insects [3]. Establishing the phylogenetic affinities of ants and bees helps us understand and reconstruct patterns of social evolution as well as fully appreciate the biological implications of the switch from carnivory to pollen feeding (pollenivory). Despite recent advancements in aculeate phylogeny [4-11], considerable uncertainty remains regarding higher-level relationships within Aculeata, including the phylogenetic affinities of ants and bees [5-7]. We used ultraconserved element (UCE) phylogenomics [7, 12] to resolve relationships among stinging-wasp families, gathering sequence data from >800 UCE loci and 187 samples, including 30 out of 31 aculeate families. We analyzed the 187-taxon dataset using multiple analytical approaches, and we evaluated several alternative taxon sets. We also tested alternative hypotheses for the phylogenetic positions of ants and bees. Our results present a highly supported phylogeny of the stinging wasps. Most importantly, we find unequivocal evidence that ants are the sister group to bees+apoid wasps (Apoidea) and that bees are nested within a paraphyletic Crabronidae. We also demonstrate that taxon choice can fundamentally impact tree topology and clade support in phylogenomic inference.

  10. Chemical Ecology of Stingless Bees.

    PubMed

    Leonhardt, Sara Diana

    2017-04-01

    Stingless bees (Hymenoptera, Apidae: Meliponini) represent a highly diverse group of social bees confined to the world's tropics and subtropics. They show a striking diversity of structural and behavioral adaptations and are important pollinators of tropical plants. Despite their diversity and functional importance, their ecology, and especially chemical ecology, has received relatively little attention, particularly compared to their relative the honeybee, Apis mellifera. Here, I review various aspects of the chemical ecology of stingless bees, from communication over resource allocation to defense. I list examples in which functions of specific compounds (or compound groups) have been demonstrated by behavioral experiments, and show that many aspects (e.g., queen-worker interactions, host-parasite interactions, neuronal processing etc.) remain little studied. This review further reveals that the vast majority of studies on the chemical ecology of stingless bees have been conducted in the New World, whereas studies on Old World stingless bees are still comparatively rare. Given the diversity of species, behaviors and, apparently, chemical compounds used, I suggest that stingless bees provide an ideal subject for studying how functional context and the need for species specificity may interact to shape pheromone diversification in social insects.

  11. Cocaine Tolerance in Honey Bees

    PubMed Central

    Søvik, Eirik; Cornish, Jennifer L.; Barron, Andrew B.

    2013-01-01

    Increasingly invertebrates are being used to investigate the molecular and cellular effects of drugs of abuse to explore basic mechanisms of addiction. However, in mammals the principle factors contributing to addiction are long-term adaptive responses to repeated drug use. Here we examined whether adaptive responses to cocaine are also seen in invertebrates using the honey bee model system. Repeated topical treatment with a low dose of cocaine rendered bees resistant to the deleterious motor effects of a higher cocaine dose, indicating the development of physiological tolerance to cocaine in bees. Cocaine inhibits biogenic amine reuptake transporters, but neither acute nor repeated cocaine treatments caused measurable changes in levels of biogenic amines measured in whole bee brains. Our data show clear short and long-term behavioural responses of bees to cocaine administration, but caution that, despite the small size of the bee brain, measures of biogenic amines conducted at the whole-brain level may not reveal neurochemical effects of the drug. PMID:23741423

  12. Revisiting comparisons of genetic diversity in stable and declining species: assessing genome-wide polymorphism in North American bumble bees using RAD sequencing.

    PubMed

    Lozier, J D

    2014-02-01

    Genetic variation is of key importance for a species' evolutionary potential, and its estimation is a major component of conservation studies. New DNA sequencing technologies have enabled the analysis of large portions of the genome in nonmodel species, promising highly accurate estimates of such population genetic parameters. Restriction site-associated DNA sequencing (RADseq) is used to analyse thousands of variants in the bumble bee species Bombus impatiens, which is common, and Bombus pensylvanicus, which is in decline. Previous microsatellite-based analyses have shown that gene diversity is lower in the declining B. pensylvanicus than in B. impatiens. RADseq nucleotide diversities appear much more similar in the two species. Both species exhibit allele frequencies consistent with historical population expansions. Differences in diversity observed at microsatellites thus do not appear to have arisen from long-term differences in population size and are either recent in origin or may result from mutational processes. Additional research is needed to explain these discrepancies and to investigate the best ways to integrate next-generation sequencing data and more traditional molecular markers in studies of genetic diversity.

  13. Effects of varroa mites and bee diseases on pollination efficacy of honey bees

    USDA-ARS?s Scientific Manuscript database

    Varroa mites and viral diseases are known to affect the efficiency of crop pollination by honey. This study elucidates effects of varroa mites and bee diseases on the foraging behavior of adult bees and the consequences on successful fruit pollination. Four honey bee colonies of about 4,500 bees eac...

  14. Honey Bee Colonies Remote Monitoring System

    PubMed Central

    Gil-Lebrero, Sergio; Quiles-Latorre, Francisco Javier; Ortiz-López, Manuel; Sánchez-Ruiz, Víctor; Gámiz-López, Victoria; Luna-Rodríguez, Juan Jesús

    2016-01-01

    Bees are very important for terrestrial ecosystems and, above all, for the subsistence of many crops, due to their ability to pollinate flowers. Currently, the honey bee populations are decreasing due to colony collapse disorder (CCD). The reasons for CCD are not fully known, and as a result, it is essential to obtain all possible information on the environmental conditions surrounding the beehives. On the other hand, it is important to carry out such information gathering as non-intrusively as possible to avoid modifying the bees’ work conditions and to obtain more reliable data. We designed a wireless-sensor networks meet these requirements. We designed a remote monitoring system (called WBee) based on a hierarchical three-level model formed by the wireless node, a local data server, and a cloud data server. WBee is a low-cost, fully scalable, easily deployable system with regard to the number and types of sensors and the number of hives and their geographical distribution. WBee saves the data in each of the levels if there are failures in communication. In addition, the nodes include a backup battery, which allows for further data acquisition and storage in the event of a power outage. Unlike other systems that monitor a single point of a hive, the system we present monitors and stores the temperature and relative humidity of the beehive in three different spots. Additionally, the hive is continuously weighed on a weighing scale. Real-time weight measurement is an innovation in wireless beehive—monitoring systems. We designed an adaptation board to facilitate the connection of the sensors to the node. Through the Internet, researchers and beekeepers can access the cloud data server to find out the condition of their hives in real time. PMID:28036061

  15. Entomology: A Bee Farming a Fungus.

    PubMed

    Oldroyd, Benjamin P; Aanen, Duur K

    2015-11-16

    Farming is done not only by humans, but also by some ant, beetle and termite species. With the discovery of a stingless bee farming a fungus that provides benefits to its larvae, bees can be added to this list.

  16. Honey Bees Inspired Optimization Method: The Bees Algorithm

    PubMed Central

    Yuce, Baris; Packianather, Michael S.; Mastrocinque, Ernesto; Pham, Duc Truong; Lambiase, Alfredo

    2013-01-01

    Optimization algorithms are search methods where the goal is to find an optimal solution to a problem, in order to satisfy one or more objective functions, possibly subject to a set of constraints. Studies of social animals and social insects have resulted in a number of computational models of swarm intelligence. Within these swarms their collective behavior is usually very complex. The collective behavior of a swarm of social organisms emerges from the behaviors of the individuals of that swarm. Researchers have developed computational optimization methods based on biology such as Genetic Algorithms, Particle Swarm Optimization, and Ant Colony. The aim of this paper is to describe an optimization algorithm called the Bees Algorithm, inspired from the natural foraging behavior of honey bees, to find the optimal solution. The algorithm performs both an exploitative neighborhood search combined with random explorative search. In this paper, after an explanation of the natural foraging behavior of honey bees, the basic Bees Algorithm and its improved versions are described and are implemented in order to optimize several benchmark functions, and the results are compared with those obtained with different optimization algorithms. The results show that the Bees Algorithm offering some advantage over other optimization methods according to the nature of the problem. PMID:26462528

  17. Honey bees, neonicotinoids and bee incident reports: the Canadian situation.

    PubMed

    Cutler, G Christopher; Scott-Dupree, Cynthia D; Drexler, David M

    2014-05-01

    Neonicotinoid insecticides have been the target of much scrutiny as possible causes of recent declines observed in pollinator populations. Although neonicotinoids have been implicated in honey bee pesticide incidents, there has been little examination of incident report data. Here we summarize honey bee incident report data obtained from the Canadian Pest Management Regulatory Agency (PMRA). In Canada, there were very few honey bee incidents reported in 2007-2011 and data were not collected prior to 2007. In 2012, a significant number of incidents were reported in the province of Ontario, where exposure to neonicotinoid dust during planting of corn was suspected to have caused the incident in up to 70% of cases. Most of these incidents were classified as 'minor' by the PMRA, and only six cases were considered 'moderate' or 'major'. In that same year, there were over three times as many moderate or major incidents due to older non-neonicotinoid pesticides, involving numbers of hives or bees far greater than the number of moderate or major incidents suspected to be due to neonicotinoid poisoning. These data emphasize that, while exposure of honey bees to neonicotinoid-contaminated dust during corn planting needs to be mitigated, other pesticides also pose a risk. © 2013 Society of Chemical Industry.

  18. Conditional discrimination and response chains by worker bumblebees (Bombus impatiens Cresson, Hymenoptera: Apidae).

    PubMed

    Mirwan, Hamida B; Kevan, Peter G

    2015-09-01

    We trained worker bumblebees to discriminate arrays of artificial nectaries (one, two, and three microcentrifuge tubes inserted into artificial flowers) from which they could forage in association with their location in a three-compartmental maze. Additionally, we challenged bees to learn to accomplish three different tasks in a fixed sequence during foraging. To enter the main three-compartmented foraging arena, they had first to slide open doors in an entry box to be able to proceed to an artificial flower patch in the main arena where they had to lift covers to the artificial nectaries from which they then fed. Then, the bees had to return to the entrance way to their hive, but to actually enter, were challenged to rotate a vertically oriented disc to expose the entry hole. The bees were adept at associating the array of nectaries with their position in the compartmental maze (one nectary in compartment one, two in two, and three in three), taking about six trials to arrive at almost error-free foraging. Over all it took the bees three days of shaping to become more or less error free at the multi-step suite of sequential task performances. Thus, they had learned where they were in the chain sequence, which array and in which compartment was rewarding, how to get to the rewarding array in the appropriate compartment, and finally how to return as directly as possible to their hive entrance, open the entrance, and re-enter the hive. Our experiments were not designed to determine the specific nature of the cues the bees used, but our results strongly suggest that the tested bees developed a sense of subgoals that needed to be achieved by recognizing the array of elements in a pattern and possibly chain learning in order to achieve the ultimate goal of successfully foraging and returning to their colony. Our results also indicate that the bees had organized their learning by a hierarchy as evidenced by their proceeding to completion of the ultimate goal without

  19. Pollution monitoring using bees: a new service provided by honey bees

    SciTech Connect

    Bromenshenk, J.J.; Thomas, J.M.; Simpson, J.C.; Bishop, M.

    1983-10-01

    The objectives are to provide a tool for assessing pollutant distributions and the effects of pollutants on living systems. The potential of bees as pollution monitors was studied by examining bees exposed to toxic metals near a smelter in Montana and bees in the area surrounding a hazardous waste disposal site near Puget Sound, Washington. Levels of toxic metals in the bees and brood survival were examined. It was concluded bees were, indeed, suitable indicators of pollution levels. (ACR)

  20. Do Honey Bees Increase Sunflower See Yields?

    USDA-ARS?s Scientific Manuscript database

    Ten self-fertile commercial sunflowers cultivars were evaluated for seed set with and without exposure to bees. In the first planting, the number of foraging honey bees was smaller than in the second, and seed set for most cultivars did not differ between those excluding bees and ones that were ope...

  1. Flowers and Wild Megachilid Bees Share Microbes.

    PubMed

    McFrederick, Quinn S; Thomas, Jason M; Neff, John L; Vuong, Hoang Q; Russell, Kaleigh A; Hale, Amanda R; Mueller, Ulrich G

    2017-01-01

    Transmission pathways have fundamental influence on microbial symbiont persistence and evolution. For example, the core gut microbiome of honey bees is transmitted socially and via hive surfaces, but some non-core bacteria associated with honey bees are also found on flowers, and these bacteria may therefore be transmitted indirectly between bees via flowers. Here, we test whether multiple flower and wild megachilid bee species share microbes, which would suggest that flowers may act as hubs of microbial transmission. We sampled the microbiomes of flowers (either bagged to exclude bees or open to allow bee visitation), adults, and larvae of seven megachilid bee species and their pollen provisions. We found a Lactobacillus operational taxonomic unit (OTU) in all samples but in the highest relative and absolute abundances in adult and larval bee guts and pollen provisions. The presence of the same bacterial types in open and bagged flowers, pollen provisions, and bees supports the hypothesis that flowers act as hubs of transmission of these bacteria between bees. The presence of bee-associated bacteria in flowers that have not been visited by bees suggests that these bacteria may also be transmitted to flowers via plant surfaces, the air, or minute insect vectors such as thrips. Phylogenetic analyses of nearly full-length 16S rRNA gene sequences indicated that the Lactobacillus OTU dominating in flower- and megachilid-associated microbiomes is monophyletic, and we propose the name Lactobacillus micheneri sp. nov. for this bacterium.

  2. Preventing bee mortality with RNA interference

    USDA-ARS?s Scientific Manuscript database

    We present a real world example of the successful use of an RNAi product for disease control. RNAi increased bee health in the presence of the bee viral pathogen, IAPV. The importance of honey bees to the world economy far surpasses their contribution in terms of honey production; they are responsib...

  3. Global Status of Honey Bee Mites

    USDA-ARS?s Scientific Manuscript database

    Parasitic bee mites have become a major problem to both beekeepers and honey bees. This chapter updates the latest information we have on the three mite species, Acarapis (tracheal), Varroa and Tropilaelaps that are currently a threat to honey bees. It also updates the current information on the ...

  4. Antioxidant Activity of Sonoran Desert Bee Pollen

    USDA-ARS?s Scientific Manuscript database

    Bee products have been consumed by mankind since antiquity and their health benefits are becoming more apparent. Bee pollen (pollen collected by honey bees) was collected in the high intensity ultraviolet (UV) Sonoran desert and was analyzed by the anti-2,2-diphenyl-1-picryhydrazyl (DPPH) assay and...

  5. Hologenome theory and the honey bee pathosphere

    USDA-ARS?s Scientific Manuscript database

    Recent research shows substantial genomic diversity among the parasites and pathogens honey bees encounter, a robust microbiota living within bees, and a genome-level view of relationships across global honey bee races. Different combinations of these genomic complexes may explain regional variatio...

  6. A Review of Bee Virology Progress

    USDA-ARS?s Scientific Manuscript database

    Honey bees play a vital role in global food production and sustainable ecological systems. However, honey bee colony losses at the rate of 20%-30% per year in recent years have been devastating to the agricultural industry and ecosystem that rely on honey bees for pollination. Among biotic and abiot...

  7. Bee health and international trade.

    PubMed

    Shimanuki, H; Knox, D A

    1997-04-01

    The international trade in bee products is a complex issue as a result of the diverse uses of these products. This is especially true with regard to honey. In most cases, honey is imported for human consumption: the high purchase and shipping costs preclude the use of honey as feed for bees. For these reasons, the risk of transmitting disease through honey is minimal. However, this risk should not be ignored, especially in those countries where American foulbrood is not known to occur. The importation of pollen for bee feed poses a definite risk, especially since there are no acceptable procedures for determining whether pollen is free from pathogens, insects and mites. Routine drying of pollen would reduce the survival of mites and insects, but would not have any impact on bacterial spores. Phytosanitary certificates should be required for the importation of honey and pollen when destined for bee feed. The declaration on the phytosanitary certificate should include country of origin, and should state whether the following bee diseases and parasitic mites are present: American foulbrood disease, European foulbrood disease, chalkbrood disease, Varroa jacobsoni and Tropilaelaps clareae.

  8. Swimming of the Honey Bees

    NASA Astrophysics Data System (ADS)

    Roh, Chris; Gharib, Morteza

    2016-11-01

    When the weather gets hot, nursing honey bees nudge foragers to collect water for thermoregulation of their hive. While on their mission to collect water, foragers sometimes get trapped on the water surface, forced to interact with a different fluid environment. In this study, we present the survival strategy of the honey bees at the air-water interface. A high-speed videography and shadowgraph were used to record the honey bees swimming. A unique thrust mechanism through rapid vibration of their wings at 60 to 150 Hz was observed. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1511414; additional support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.

  9. Optic neuritis after bee sting.

    PubMed

    Choi, M Y; Cho, S H

    2000-06-01

    The purpose of this report is to document an unusual case of fully recovered vision after optic neuritis caused by bee sting. A 46-year-old man presented with sudden visual loss after being stung by a bee on the left conjunctiva. He developed optic disc swelling and there was a delay in the P100 wave of the pattern visual evoked potential (VEP). The patient received acute treatment, with intravenous methylprednisolone followed by oral prednisolone. Two days later, visual acuity in the left eye was recovered to 20/20 and P100 latency in pattern VEP was also normalized. Furthermore, visual field and color vision tests revealed no remaining abnormalities. This case suggests that early corticosteroid treatment is effective in optic neuritis caused by bee sting.

  10. Chronic exposure to a neonicotinoid increases expression of antimicrobial peptide genes in the bumblebee Bombus impatiens

    PubMed Central

    Simmons, William R.; Angelini, David R.

    2017-01-01

    Bumblebees are important pollinators in wild and agricultural settings. In recent decades pollinator declines have been linked to the effects of increased pesticide use and the spread of disease. Synergy between these factors has been suggested, but no physiological mechanism has been identified. This study examines the connection between neonicotinoid exposure and innate immune function in the bumblebee Bombus impatiens, which is an important wild and commercial pollinator in eastern North America. Experimental colonies in the field were enclosed and provided pollen and sugar syrup containing an agriculturally relevant range of imidacloprid concentrations. Bumblebees were collected from colonies over four weeks, and the expression of antimicrobial peptides was measured using multiplex quantitative real time PCR. Significant increases in the expression of abaecin, apidaecin and hymenoptaecin were found over time in treatments receiving moderate to high concentrations of the pesticide. Responses were dependent on time of exposure and dose. These results indicate that immune function in bumblebees is affected by neonicotinoid exposure and suggest a physiological mechanism by which neonicotinoids may impact the innate immune function of bumblebee pollinators in wild and agricultural habitats. PMID:28322347

  11. Chronic exposure to a neonicotinoid increases expression of antimicrobial peptide genes in the bumblebee Bombus impatiens.

    PubMed

    Simmons, William R; Angelini, David R

    2017-03-21

    Bumblebees are important pollinators in wild and agricultural settings. In recent decades pollinator declines have been linked to the effects of increased pesticide use and the spread of disease. Synergy between these factors has been suggested, but no physiological mechanism has been identified. This study examines the connection between neonicotinoid exposure and innate immune function in the bumblebee Bombus impatiens, which is an important wild and commercial pollinator in eastern North America. Experimental colonies in the field were enclosed and provided pollen and sugar syrup containing an agriculturally relevant range of imidacloprid concentrations. Bumblebees were collected from colonies over four weeks, and the expression of antimicrobial peptides was measured using multiplex quantitative real time PCR. Significant increases in the expression of abaecin, apidaecin and hymenoptaecin were found over time in treatments receiving moderate to high concentrations of the pesticide. Responses were dependent on time of exposure and dose. These results indicate that immune function in bumblebees is affected by neonicotinoid exposure and suggest a physiological mechanism by which neonicotinoids may impact the innate immune function of bumblebee pollinators in wild and agricultural habitats.

  12. Expression profile of the sex determination gene doublesex in a gynandromorph of bumblebee, Bombus ignitus

    NASA Astrophysics Data System (ADS)

    Ugajin, Atsushi; Matsuo, Koshiro; Kubo, Ryohei; Sasaki, Tetsuhiko; Ono, Masato

    2016-04-01

    Gynandromorphy that has both male and female features is known in many insect orders, including Hymenoptera. In most cases, however, only external morphology and behavioral aspects have been studied. We found a gynandromorph of bumblebee, Bombus ignitus, that showed almost bilateral distribution of external sexual traits, with male characters observed on the left side and female characters on the right side. This individual never exhibited sexual behavior toward new queens. The dissection of the head part showed that it had bilaterally dimorphic labial glands, only the left of which was well developed and synthesized male-specific pheromone components. In contrast, the gynandromorph possessed an ovipositor and a pair of ovaries in the abdominal part, suggesting that it had a uniformly female reproductive system. Furthermore, we characterized several internal organs of the gynandromorph by a molecular biological approach. The expression analyses of a sex determination gene, doublesex, in the brain, the fat bodies, the hindgut, and the ovaries of the gynandromorph revealed a male-type expression pattern exclusively in the left brain hemisphere and consistent female-type expression in other tissues. These findings clearly indicate the sexual discordance between external traits and internal organs in the gynandromorph. The results of genetic analyses using microsatellite markers suggested that this individual consisted of both genetically male- and female-type tissues.

  13. Limits to vertical force and power production in bumblebees (Hymenoptera: Bombus impatiens).

    PubMed

    Buchwald, R; Dudley, R

    2010-02-01

    Maximum vertical forces produced by flying animals can be difficult to identify unequivocally, but potentially indicate general limits to aerodynamic force and muscle power output. We used two methods (i.e. incremental addition of supplemental mass and asymptotic load lifting) to determine both the intraspecific allometry of and methodological differences in estimates of maximum flight performance for the bumblebee Bombus impatiens. We found that incremental mass addition underestimated maximum lifting capacity by approximately 18% relative to values obtained by asymptotically increasing the applied load during a lifting bout. In asymptotic loading, bumblebees lifted on average 53% of their body weight, and demonstrated a significantly negative allometry of maximum aerodynamic force production relative to thoracic muscle mass. Estimates of maximum body mass-specific mechanical power output increased intraspecifically with body mass to the 0.38-0.50 power, depending on values assumed for the profile drag coefficient. We also found a significant reduction in vertical force production when both hindwings were removed. Limits to load-lifting capacity ultimately co-occur with an upper bound on stroke amplitude (approximately 145 deg.). Although thoracic muscle mass showed positive allometry, overall load-lifting performance exhibited significant size-dependent degradation.

  14. Learned Use of Picture Cues by Bumblebees (Bombus impatiens) in a Delayed Matching Task

    PubMed Central

    Thompson, Emma; Plowright, Catherine

    2016-01-01

    Picture-object correspondence provides an alternate method of investigating delayed matching by providing a cue (picture) which may be spontaneously perceived as similar but different from a corresponding target. Memory for, and corresponding choice of, a target corresponding to a cue could be facilitated by the use of a picture. Bumblebees have been found to both easily differentiate images from corresponding objects but also spontaneously perceive a similarity between the two. Herein, an approach was designed to test the possible use of picture cues to signal reward in a delayed matching task. Target choice preference corresponding to picture cues was tested among three bumblebee (Bombus impatiens) colonies using photograph cues (presented prior to target stimuli) corresponding to one of four target stimuli. Photograph cues were the only predictor of corresponding target reward, presented in stable locations. Rewarded and unrewarded tests show a choice preference significantly higher than chance for targets matching the cue. Results suggest that bumblebees can learn to use picture cues in a delayed matching task. Furthermore, experience, conditions of reward inconsistency and location, are discussed as possible contributing factors to learning in a delayed matching task. PMID:27754410

  15. Chemical communication is not sufficient to explain reproductive inhibition in the bumblebee Bombus impatiens

    PubMed Central

    Padilla, Mario; Amsalem, Etya; Altman, Naomi; Hefetz, Abraham

    2016-01-01

    Reproductive division of labour is a hallmark of eusociality, but disentangling the underlying proximate mechanisms can be challenging. In bumblebees, workers isolated from the queen can activate their ovaries and lay haploid, male eggs. We investigated if volatile, contact, visual or behavioural cues produced by the queen or brood mediate reproductive dominance in Bombus impatiens. Exposure to queen-produced volatiles, brood-produced volatiles and direct contact with pupae did not reduce worker ovary activation; only direct contact with the queen could reduce ovary activation. We evaluated behaviour, physiology and gene expression patterns in workers that were reared in chambers with all stages of brood and a free queen, caged queen (where workers could contact the queen, but the queen was unable to initiate interactions) or no queen. Workers housed with a caged queen or no queen fully activated their ovaries, whereas ovary activation in workers housed with a free queen was completely inhibited. The caged queen marginally reduced worker aggression and expression of an aggression-associated gene relative to queenless workers. Thus, queen-initiated behavioural interactions appear necessary to establish reproductive dominance. Queen-produced chemical cues may function secondarily in a context-specific manner to augment behavioural cues, as reliable or honest signal. PMID:27853577

  16. Solar-Terrestrial and Terrestrial Science

    NASA Astrophysics Data System (ADS)

    Ryan, J. M.; Aikin, A. C.; Cliver, E. W.; Rieger, E.; Share, G. H.

    SMM's Impact on Solar-Terrestrial Studies Paradigm Shift in Solar-Terrestrial Physics Two Classes of SEP Events γ-Rays from the Earth Galactic Cosmic Ray-Induced γ-Rays from the Earth Solar Cosmic Ray-Induced γ-Rays from the Earth Transient Radiation Belts from Orbiting Nuclear Reactors Mesospheric Chemistry Studies with UVSP Ozone Measurements Molecular Oxygen Measurements

  17. Identifying bacterial predictors of honey bee health.

    PubMed

    Budge, Giles E; Adams, Ian; Thwaites, Richard; Pietravalle, Stéphane; Drew, Georgia C; Hurst, Gregory D D; Tomkies, Victoria; Boonham, Neil; Brown, Mike

    2016-11-01

    Non-targeted approaches are useful tools to identify new or emerging issues in bee health. Here, we utilise next generation sequencing to highlight bacteria associated with healthy and unhealthy honey bee colonies, and then use targeted methods to screen a wider pool of colonies with known health status. Our results provide the first evidence that bacteria from the genus Arsenophonus are associated with poor health in honey bee colonies. We also discovered Lactobacillus and Leuconostoc spp. were associated with healthier honey bee colonies. Our results highlight the importance of understanding how the wider microbial population relates to honey bee colony health.

  18. The plight of the bees

    USGS Publications Warehouse

    Spivak, M.; Mader, E.; Vaughan, M.; Euliss, N.H.

    2011-01-01

    The loss of biodiversity is a trend that is garnering much concern. As organisms have evolved mutualistic and synergistic relationships, the loss of one or a few species can have a much wider environmental impact. Since much pollination is facilitated by bees, the reported colony collapse disorder has many worried of widespread agricultural fallout and thus deleterious impact on human foodstocks. In this Feature, Spivak et al. review what is known of the present state of bee populations and provide information on how to mitigate and reverse the trend. ?? 2010 American Chemical Society.

  19. Ambient air concentration of sulfur dioxide affects flight activity in bees

    SciTech Connect

    Ginevan, M.E.; Lane, D.D.; Greenberg, L.

    1980-10-01

    Three long-term (16 to 29 days) low-level (0.14 to 0.28 ppM) sulfur dioxide fumigations showed that exposure tothis gas has deleterious effects on male sweat bees (Lasioglossum zephrum). Although effects on mortality were equivocal, flight activity was definitely reduced. Because flight is necessary for successful mating behavior, the results suggest that sulfur dioxide air pollution could adversely affect this and doubtless other terrestrial insects.

  20. Bee cups: Single-use cages for honey bee experiments

    USDA-ARS?s Scientific Manuscript database

    Honey bees face challenges ranging from poor nutrition to exposure to parasites, pathogens, and environmental chemicals. These challenges drain colony resources and have been tied to both subtle and extreme colony declines, including the enigmatic Colony Collapse Disorder (CCD). Understanding how ...

  1. Filtering across Spatial Scales: Phylogeny, Biogeography and Community Structure in Bumble Bees

    PubMed Central

    Harmon-Threatt, Alexandra N.; Ackerly, David D.

    2013-01-01

    Despite the expansion of phylogenetic community analysis to understand community assembly, few studies have used these methods on mobile organisms and it has been suggested the local scales that are typically considered may be too small to represent the community as perceived by organisms with high mobility. Mobility is believed to allow species to mediate competitive interactions quickly and thus highly mobile species may appear randomly assembled in local communities. At larger scales, however, biogeographical processes could cause communities to be either phylogenetically clustered or even. Using phylogenetic community analysis we examined patterns of relatedness and trait similarity in communities of bumble bees (Bombus) across spatial scales comparing: local communities to regional pools, regional communities to continental pools and the continental community to a global species pool. Species composition and data on tongue lengths, a key foraging trait, were used to test patterns of relatedness and trait similarity across scales. Although expected to exhibit limiting similarity, local communities were clustered both phenotypically and phylogenetically. Larger spatial scales were also found to have more phylogenetic clustering but less trait clustering. While patterns of relatedness in mobile species have previously been suggested to exhibit less structure in local communities and to be less clustered than immobile species, we suggest that mobility may actually allow communities to have more similar species that can simply limit direct competition through mobility. PMID:23544141

  2. Rising atmospheric CO2 is reducing the protein concentration of a floral pollen source essential for North American bees.

    PubMed

    Ziska, Lewis H; Pettis, Jeffery S; Edwards, Joan; Hancock, Jillian E; Tomecek, Martha B; Clark, Andrew; Dukes, Jeffrey S; Loladze, Irakli; Polley, H Wayne

    2016-04-13

    At present, there is substantive evidence that the nutritional content of agriculturally important food crops will decrease in response to rising levels of atmospheric carbon dioxide, Ca However, whether Ca-induced declines in nutritional quality are also occurring for pollinator food sources is unknown. Flowering late in the season, goldenrod (Solidago spp.) pollen is a widely available autumnal food source commonly acknowledged by apiarists to be essential to native bee (e.g. Bombus spp.) and honeybee (Apis mellifera) health and winter survival. Using floral collections obtained from the Smithsonian Natural History Museum, we quantified Ca-induced temporal changes in pollen protein concentration of Canada goldenrod (Solidago canadensis), the most wide spread Solidago taxon, from hundreds of samples collected throughout the USA and southern Canada over the period 1842-2014 (i.e. a Ca from approx. 280 to 398 ppm). In addition, we conducted a 2 year in situtrial of S. Canadensis populations grown along a continuous Ca gradient from approximately 280 to 500 ppm. The historical data indicated a strong significant correlation between recent increases in Ca and reductions in pollen protein concentration (r(2)= 0.81). Experimental data confirmed this decrease in pollen protein concentration, and indicated that it would be ongoing as Ca continues to rise in the near term, i.e. to 500 ppm (r(2)= 0.88). While additional data are needed to quantify the subsequent effects of reduced protein concentration for Canada goldenrod on bee health and population stability, these results are the first to indicate that increasing Ca can reduce protein content of a floral pollen source widely used by North American bees. © 2016 The Author(s).

  3. Rising atmospheric CO2 is reducing the protein concentration of a floral pollen source essential for North American bees

    PubMed Central

    Ziska, Lewis H.; Pettis, Jeffery S.; Edwards, Joan; Hancock, Jillian E.; Tomecek, Martha B.; Clark, Andrew; Dukes, Jeffrey S.; Loladze, Irakli; Polley, H. Wayne

    2016-01-01

    At present, there is substantive evidence that the nutritional content of agriculturally important food crops will decrease in response to rising levels of atmospheric carbon dioxide, Ca. However, whether Ca-induced declines in nutritional quality are also occurring for pollinator food sources is unknown. Flowering late in the season, goldenrod (Solidago spp.) pollen is a widely available autumnal food source commonly acknowledged by apiarists to be essential to native bee (e.g. Bombus spp.) and honeybee (Apis mellifera) health and winter survival. Using floral collections obtained from the Smithsonian Natural History Museum, we quantified Ca-induced temporal changes in pollen protein concentration of Canada goldenrod (Solidago canadensis), the most widespread Solidago taxon, from hundreds of samples collected throughout the USA and southern Canada over the period 1842–2014 (i.e. a Ca from approx. 280 to 398 ppm). In addition, we conducted a 2 year in situ trial of S. canadensis populations grown along a continuous Ca gradient from approximately 280 to 500 ppm. The historical data indicated a strong significant correlation between recent increases in Ca and reductions in pollen protein concentration (r2 = 0.81). Experimental data confirmed this decrease in pollen protein concentration, and indicated that it would be ongoing as Ca continues to rise in the near term, i.e. to 500 ppm (r2 = 0.88). While additional data are needed to quantify the subsequent effects of reduced protein concentration for Canada goldenrod on bee health and population stability, these results are the first to indicate that increasing Ca can reduce protein content of a floral pollen source widely used by North American bees. PMID:27075256

  4. Chronic bee paralysis virus and Nosema ceranae experimental co-infection of winter honey bee workers (Apis mellifera L.)

    USDA-ARS?s Scientific Manuscript database

    Chronic bee paralysis virus (CBPV) is an important viral disease of adult bees which induces significant losses in honey bee colonies. In this study winter worker bees were experimentally infected using three different experiments. Bees were inoculated orally or topically with CBPV to evaluate the l...

  5. Ants, Wasps, and Bees (Hymenoptera)

    USDA-ARS?s Scientific Manuscript database

    Stinging wasps, bees, and ants are a problem for farm workers, particularly at harvest when these insects are attracted to ripe fruits. Researchers at the USDA-ARS Yakima Agricultural Research Laboratory, Wapato, WA, together with personnel at Oral Roberts University compiled available information o...

  6. Sickness Behavior in Honey Bees

    PubMed Central

    Kazlauskas, Nadia; Klappenbach, Martín; Depino, Amaicha M.; Locatelli, Fernando F.

    2016-01-01

    During an infection, animals suffer several changes in their normal physiology and behavior which may include lethargy, appetite loss, and reduction in grooming and general movements. This set of alterations is known as sickness behavior and although it has been extensively believed to be orchestrated primarily by the immune system, a relevant role for the central nervous system has also been established. The aim of the present work is to develop a simple animal model to allow studying how the immune and the nervous systems interact coordinately during an infection. We administered a bacterial lipopolysaccharide (LPS) into the thorax of honey bees to mimic a bacterial infection, and then we evaluated a set of stereotyped behaviors of the animals that might be indicative of sickness behavior. First, we show that this immune challenge reduces the locomotor activity of the animals in a narrow time window after LPS injection. Furthermore, bees exhibit a loss of appetite 60 and 90 min after injection, but not 15 h later. We also demonstrate that LPS injection reduces spontaneous antennal movements in harnessed animals, which suggests a reduction in the motivational state of the bees. Finally, we show that the LPS injection diminishes the interaction between animals, a crucial behavior in social insects. To our knowledge these results represent the first systematic description of sickness behavior in honey bees and provide important groundwork for the study of the interaction between the immune and the neural systems in an insect model. PMID:27445851

  7. Neonicotinoids act like endocrine disrupting chemicals in newly-emerged bees and winter bees.

    PubMed

    Baines, Danica; Wilton, Emily; Pawluk, Abbe; de Gorter, Michael; Chomistek, Nora

    2017-09-08

    Accumulating evidence suggests that neonicotinoids may have long-term adverse effects on bee health, yet our understanding of how this could occur is incomplete. Pesticides can act as endocrine disrupting chemicals (EDCs) in animals providing characteristic multiphasic dose-response curves and non-lethal endpoints in toxicity studies. However, it is not known if neonicotinoids act as EDCs in bees. To address this issue, we performed oral acute and chronic toxicity studies including concentrations recorded in nectar and pollen, applying acetamiprid, clothianidin, imidacloprid, and thiamethoxam to bumble bees, honey bees and leafcutter bees, the three most common bee species managed for pollination. In acute toxicity studies, late-onset symptoms, such as ataxia, were recorded as non-lethal endpoints for all three bee species. Clothianidin and thiamethoxam produced biphasic dose-response curves for all three bee species. Clothianidin and thiamethoxam were extremely toxic to winter worker honey bees prior to brood production in spring, making this the most sensitive bee stage identified to date. Chronic exposure to field-realistic levels of neonicotinoids reduced bee survival and caused significant late-onset symptoms for all three bee species. Given these findings, neonicotinoid risk should be reevaluated to address the EDC-like behavior and the sensitivity of winter worker honey bees.

  8. Corneal bee sting misdiagnosed as viral keratitis.

    PubMed

    Jain, Vandana; Shome, Debraj; Natarajan, Sundaram

    2007-12-01

    To report a case of chronic keratouveitis caused by a missed bee sting injury. A 17-year-old boy was referred for management of unresponsive viral keratouveitis. Ocular examination revealed corneal edema and scarring, atrophic patches on the iris, and anterior polar cataracts. Surprisingly, examination also revealed a retained intracorneal bee stinger. A retrospective inquiry confirmed a bee sting injury 2 years ago. The patient was started on medical treatment and underwent operative removal of the bee stinger. Postsurgery, visual acuity improved, and the corneal edema regressed over a 1-month follow-up. In cases of chronic keratouveitis, a meticulous examination is mandatory to rule out unusual causes like a retained corneal bee stinger. A retained intracorneal bee stinger may result in long-term corneal inflammation, which may not be controlled adequately with topical steroids. It should be removed, irrespective of the duration since the injury.

  9. Dynamic microbiome evolution in social bees

    PubMed Central

    Kwong, Waldan K.; Medina, Luis A.; Koch, Hauke; Sing, Kong-Wah; Soh, Eunice Jia Yu; Ascher, John S.; Jaffé, Rodolfo; Moran, Nancy A.

    2017-01-01

    The highly social (eusocial) corbiculate bees, comprising the honey bees, bumble bees, and stingless bees, are ubiquitous insect pollinators that fulfill critical roles in ecosystem services and human agriculture. Here, we conduct wide sampling across the phylogeny of these corbiculate bees and reveal a dynamic evolutionary history behind their microbiota, marked by multiple gains and losses of gut associates, the presence of generalist as well as host-specific strains, and patterns of diversification driven, in part, by host ecology (for example, colony size). Across four continents, we found that different host species have distinct gut communities, largely independent of geography or sympatry. Nonetheless, their microbiota has a shared heritage: The emergence of the eusocial corbiculate bees from solitary ancestors appears to coincide with the acquisition of five core gut bacterial lineages, supporting the hypothesis that host sociality facilitates the development and maintenance of specialized microbiomes. PMID:28435856

  10. Dynamic microbiome evolution in social bees.

    PubMed

    Kwong, Waldan K; Medina, Luis A; Koch, Hauke; Sing, Kong-Wah; Soh, Eunice Jia Yu; Ascher, John S; Jaffé, Rodolfo; Moran, Nancy A

    2017-03-01

    The highly social (eusocial) corbiculate bees, comprising the honey bees, bumble bees, and stingless bees, are ubiquitous insect pollinators that fulfill critical roles in ecosystem services and human agriculture. Here, we conduct wide sampling across the phylogeny of these corbiculate bees and reveal a dynamic evolutionary history behind their microbiota, marked by multiple gains and losses of gut associates, the presence of generalist as well as host-specific strains, and patterns of diversification driven, in part, by host ecology (for example, colony size). Across four continents, we found that different host species have distinct gut communities, largely independent of geography or sympatry. Nonetheless, their microbiota has a shared heritage: The emergence of the eusocial corbiculate bees from solitary ancestors appears to coincide with the acquisition of five core gut bacterial lineages, supporting the hypothesis that host sociality facilitates the development and maintenance of specialized microbiomes.

  11. Decline and conservation of bumble bees.

    PubMed

    Goulson, D; Lye, G C; Darvill, B

    2008-01-01

    Declines in bumble bee species in the past 60 years are well documented in Europe, where they are driven primarily by habitat loss and declines in floral abundance and diversity resulting from agricultural intensification. Impacts of habitat degradation and fragmentation are likely to be compounded by the social nature of bumble bees and their largely monogamous breeding system, which renders their effective population size low. Hence, populations are susceptible to stochastic extinction events and inbreeding. In North America, catastrophic declines of some bumble bee species since the 1990s are probably attributable to the accidental introduction of a nonnative parasite from Europe, a result of global trade in domesticated bumble bee colonies used for pollination of greenhouse crops. Given the importance of bumble bees as pollinators of crops and wildflowers, steps must be taken to prevent further declines. Suggested measures include tight regulation of commercial bumble bee use and targeted use of environmentally comparable schemes to enhance floristic diversity in agricultural landscapes.

  12. Gauging the effect of honey bee pollen collection on native bee communities

    USDA-ARS?s Scientific Manuscript database

    The broad question --“Do honey bees compete with native bees?” -- has no singular answer for wildlands, being functions of: 1) the variable stocking densities of bees, and 2) unknowable carrying capacities of floral resources. The conventional approach, i.e. experimental demonstration of direct expl...

  13. Thi Qar Bee Farm Thi Qar, Iraq

    DTIC Science & Technology

    2010-04-01

    vegetation and fields where bees once gathered pollen and beekeepers face hardships from droughts and lack of financial assistance. 1...OFFICE OF THE SPECIAL INSPECTOR GENERAL FOR IRAQ RECONSTRUCTION THI QAR BEE FARM THI QAR, IRAQ SIGIR PA--09--188...1. REPORT DATE 01 APR 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE Thi Qar Bee Farm Thi Qar, Iraq 5a

  14. Honey Bee Hemocyte Profiling by Flow Cytometry

    PubMed Central

    Marringa, William J.; Krueger, Michael J.; Burritt, Nancy L.; Burritt, James B.

    2014-01-01

    Multiple stress factors in honey bees are causing loss of bee colonies worldwide. Several infectious agents of bees are believed to contribute to this problem. The mechanisms of honey bee immunity are not completely understood, in part due to limited information about the types and abundances of hemocytes that help bees resist disease. Our study utilized flow cytometry and microscopy to examine populations of hemolymph particulates in honey bees. We found bee hemolymph includes permeabilized cells, plasmatocytes, and acellular objects that resemble microparticles, listed in order of increasing abundance. The permeabilized cells and plasmatocytes showed unexpected differences with respect to properties of the plasma membrane and labeling with annexin V. Both permeabilized cells and plasmatocytes failed to show measurable mitochondrial membrane potential by flow cytometry using the JC-1 probe. Our results suggest hemolymph particulate populations are dynamic, revealing significant differences when comparing individual hive members, and when comparing colonies exposed to diverse conditions. Shifts in hemocyte populations in bees likely represent changing conditions or metabolic differences of colony members. A better understanding of hemocyte profiles may provide insight into physiological responses of honey bees to stress factors, some of which may be related to colony failure. PMID:25285798

  15. Bee sting of the cornea.

    PubMed

    Singh, G

    1984-04-01

    Irreversible heterochromia-iridis, internal ophthalmoplegia, and punctate subcapsular lenticular opacities developed in a 9-year-old girl after she received a bee sting in her right cornea. These complications persisted even after an 11-month follow-up period. To the author's knowledge, this presentation is the first of its nature. The pathogenesis of these changes is discussed and the literature is reviewed.

  16. Effects of suburbanization on forest bee communities.

    PubMed

    Carper, Adrian L; Adler, Lynn S; Warren, Paige S; Irwin, Rebecca E

    2014-04-01

    Urbanization is a dominant form of land-use change driving species distributions, abundances, and diversity. Previous research has documented the negative impacts of urbanization on the abundance and diversity of many groups of organisms. However, some organisms, such as bees, may benefit from moderate levels of development, depending on how development alters the availability of foraging and nesting resources. To determine how one type of low-intensity human development, suburbanization, affects bee abundance and diversity and the mechanisms involved, we surveyed bees across suburban and natural forests in the Raleigh-Durham area of North Carolina. We sampled for bees using a combination of bee bowls and hand-netting from March through July of 2008 and 2009. We found higher bee abundance in suburban than natural forests, and although observed species richness was greater in suburban than natural forests, there were no significant differences in rarefied richness or evenness estimates in either year. In addition, the effects of suburbanization were similar across bee species of varying ecological and life-history characteristics. At the local scale, bee abundance and species richness were both positively related to the abundance and richness of flowering species within forests, while the proportion of surrounding developed open areas, such as yards and roadsides, was a strong positive predictor of both bee abundance and richness at the landscape scale. These results suggest that open habitats and the availability of floral resources in suburban sites can support abundant and diverse bee communities and underscore the potential for native bee conservation in urban habitats.

  17. Live bee acupuncture (Bong-Chim) dermatitis: dermatitis due to live bee acupuncture therapy in Korea.

    PubMed

    Park, Joon Soo; Lee, Min Jung; Chung, Ki Hun; Ko, Dong Kyun; Chung, Hyun

    2013-12-01

    Live bee acupuncture (Bong-Chim) dermatitis is an iatrogenic disease induced by so-called live bee acupuncture therapy, which applies the honeybee (Apis cerana) stinger directly into the lesion to treat various diseases in Korea. We present two cases of live bee acupuncture dermatitis and review previously published articles about this disease. We classify this entity into three stages: acute, subacute, and chronic. The acute stage is an inflammatory reaction, such as anaphylaxis or urticaria. In the chronic stage, a foreign body granuloma may develop from the remaining stingers, similar to that of a bee sting reaction. However, in the subacute stage, unlike bee stings, we see the characteristic histological "flame" figures resulting from eosinophilic stimulation induced by excessive bee venom exposure. We consider this stage to be different from the adverse skin reaction of accidental bee sting. © 2013 The International Society of Dermatology.

  18. Terrestrial Planets: Comparative Planetology

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Papers were presented at the 47th Annual Meteoritical Society Meeting on the Comparative planetology of Terrestrial Planets. Subject matter explored concerning terrestrial planets includes: interrelationships among planets; plaentary evolution; planetary structure; planetary composition; planetary Atmospheres; noble gases in meteorites; and planetary magnetic fields.

  19. TERRESTRIAL ECOSYSTEM SIMULATOR

    EPA Science Inventory

    The Terrestrial Habitats Project at the Western Ecology Division (Corvallis, OR) is developing tools and databases to meet the needs of Program Office clients for assessing risks to wildlife and terrestrial ecosystems. Because habitat is a dynamic condition in real-world environm...

  20. V. Terrestrial vertebrates

    Treesearch

    Dean Pearson; Deborah Finch

    2011-01-01

    Within the Interior West, terrestrial vertebrates do not represent a large number of invasive species relative to invasive weeds, aquatic vertebrates, and invertebrates. However, several invasive terrestrial vertebrate species do cause substantial economic and ecological damage in the U.S. and in this region (Pimental 2000, 2007; Bergman and others 2002; Finch and...

  1. TERRESTRIAL ECOSYSTEM SIMULATOR

    EPA Science Inventory

    The Terrestrial Habitats Project at the Western Ecology Division (Corvallis, OR) is developing tools and databases to meet the needs of Program Office clients for assessing risks to wildlife and terrestrial ecosystems. Because habitat is a dynamic condition in real-world environm...

  2. Honey bees selectively avoid difficult choices.

    PubMed

    Perry, Clint J; Barron, Andrew B

    2013-11-19

    Human decision-making strategies are strongly influenced by an awareness of certainty or uncertainty (a form of metacognition) to increase the chances of making a right choice. Humans seek more information and defer choosing when they realize they have insufficient information to make an accurate decision, but whether animals are aware of uncertainty is currently highly contentious. To explore this issue, we examined how honey bees (Apis mellifera) responded to a visual discrimination task that varied in difficulty between trials. Free-flying bees were rewarded for a correct choice, punished for an incorrect choice, or could avoid choosing by exiting the trial (opting out). Bees opted out more often on difficult trials, and opting out improved their proportion of successful trials. Bees could also transfer the concept of opting out to a novel task. Our data show that bees selectively avoid difficult tasks they lack the information to solve. This finding has been considered as evidence that nonhuman animals can assess the certainty of a predicted outcome, and bees' performance was comparable to that of primates in a similar paradigm. We discuss whether these behavioral results prove bees react to uncertainty or whether associative mechanisms can explain such findings. To better frame metacognition as an issue for neurobiological investigation, we propose a neurobiological hypothesis of uncertainty monitoring based on the known circuitry of the honey bee brain.

  3. Metatranscriptomic analyses of honey bee colonies

    USDA-ARS?s Scientific Manuscript database

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World’s most important centers...

  4. Physiology and biochemistry of honey bees

    USDA-ARS?s Scientific Manuscript database

    Despite their tremendous economic importance, honey bees are not a typical model system for studying general questions of insect physiology. This is primarily due to the fact that honey bees live in complex social settings which impact their physiological and biochemical characteristics. Not surpris...

  5. Corneal bee sting with retained stinger.

    PubMed

    Smith, D G; Roberge, R J

    2001-02-01

    Bee stings of the cornea are rarely reported, but have the potential for causing serious ophthalmologic injuries. We present a case of corneal bee sting with retained stinger apparatus and associated iritis and discuss the pathologic mechanisms of injury, evaluation, and treatment of these uncommon presentations.

  6. Pathogen webs in collapsing honey bee colonies

    USDA-ARS?s Scientific Manuscript database

    Recent losses in honey bee colonies are unusual in their severity, geographical distribution, and, in some cases, failure to present recognized symptoms of known disease. Domesticated honey bees face numerous pests and pathogens, tempting hypotheses that colony collapses arise from exposure to new o...

  7. The Plight of the Honey Bee

    ERIC Educational Resources Information Center

    Hockridge, Emma

    2010-01-01

    The decline of colonies of honey bees across the world is threatening local plant biodiversity and human food supplies. Neonicotinoid pesticides have been implicated as a major cause of the problem and are banned or suspended in several countries. Other factors could also be lowering the resistance of bees to opportunist infections by, for…

  8. The Plight of the Honey Bee

    ERIC Educational Resources Information Center

    Hockridge, Emma

    2010-01-01

    The decline of colonies of honey bees across the world is threatening local plant biodiversity and human food supplies. Neonicotinoid pesticides have been implicated as a major cause of the problem and are banned or suspended in several countries. Other factors could also be lowering the resistance of bees to opportunist infections by, for…

  9. The problem of disease when domesticating bees

    USDA-ARS?s Scientific Manuscript database

    When disease strikes a hive of bees, it can devastate the colony and spread to the entire beekeeping operation. All bees are susceptible to diseases, and when they are domesticated, their population densities increase to suit human needs, making them more susceptible. Most attempts at disease contro...

  10. Climate change: bees and orchids lose touch.

    PubMed

    Willmer, Pat

    2014-12-01

    Spring temperature increases could differentially affect flowering times and pollinator flight periods, leading to asynchrony and reduced pollination. A specialist orchid-bee study combining herbarium, museum and field data shows that bee flight dates are advancing faster than orchid flowering, which could lead to significant future uncoupling.

  11. Cell culture techniques in honey bee research

    USDA-ARS?s Scientific Manuscript database

    Cell culture techniques are indispensable in most if not all life science disciplines to date. Wherever cell culture models are lacking scientific development is hampered. Unfortunately this has been and still is the case in honey bee research because permanent honey bee cell lines have not yet been...

  12. Biological effects of ultraviolet irradiation on bees

    SciTech Connect

    Es`kov, E.K.

    1995-09-01

    The influence of natural solar and artificial ultraviolet irradiation on developing bees was studied. Lethal exposures to irradiation at different stages of development were determined. The influence of irradiation on the variability of the morphometric features of bees was revealed. 5 refs., 1 fig.

  13. The Bees among Us: Modelling Occupancy of Solitary Bees

    PubMed Central

    MacIvor, J. Scott; Packer, Laurence

    2016-01-01

    Occupancy modelling has received increasing attention as a tool for differentiating between true absence and non-detection in biodiversity data. This is thought to be particularly useful when a species of interest is spread out over a large area and sampling is constrained. We used occupancy modelling to estimate the probability of three phylogenetically independent pairs of native—introduced species [Megachile campanulae (Robertson)—Megachile rotundata (Fab.), Megachile pugnata Say—Megachile centuncularis (L.), Osmia pumila Cresson—Osmia caerulescens (L.)] (Apoidea: Megachilidae) being present when repeated sampling did not always find them. Our study occurred along a gradient of urbanization and used nest boxes (bee hotels) set up over three consecutive years. Occupancy modelling discovered different patterns to those obtained by species detection and abundance-based data alone. For example, it predicted that the species that was ranked 4th in terms of detection actually had the greatest occupancy among all six species. The native M. pugnata had decreased occupancy with increasing building footprint and a similar but not significant pattern was found for the native O. pumila. Two introduced bees (M. rotundata and M. centuncularis), and one native (M. campanulae) had modelled occupancy values that increased with increasing urbanization. Occupancy probability differed among urban green space types for three of six bee species, with values for two native species (M. campanulae and O. pumila) being highest in home gardens and that for the exotic O. caerulescens being highest in community gardens. The combination of occupancy modelling with analysis of habitat variables as an augmentation to detection and abundance-based sampling is suggested to be the best way to ensure that urban habitat management results in the desired outcomes. PMID:27911954

  14. The Bees among Us: Modelling Occupancy of Solitary Bees.

    PubMed

    MacIvor, J Scott; Packer, Laurence

    2016-01-01

    Occupancy modelling has received increasing attention as a tool for differentiating between true absence and non-detection in biodiversity data. This is thought to be particularly useful when a species of interest is spread out over a large area and sampling is constrained. We used occupancy modelling to estimate the probability of three phylogenetically independent pairs of native-introduced species [Megachile campanulae (Robertson)-Megachile rotundata (Fab.), Megachile pugnata Say-Megachile centuncularis (L.), Osmia pumila Cresson-Osmia caerulescens (L.)] (Apoidea: Megachilidae) being present when repeated sampling did not always find them. Our study occurred along a gradient of urbanization and used nest boxes (bee hotels) set up over three consecutive years. Occupancy modelling discovered different patterns to those obtained by species detection and abundance-based data alone. For example, it predicted that the species that was ranked 4th in terms of detection actually had the greatest occupancy among all six species. The native M. pugnata had decreased occupancy with increasing building footprint and a similar but not significant pattern was found for the native O. pumila. Two introduced bees (M. rotundata and M. centuncularis), and one native (M. campanulae) had modelled occupancy values that increased with increasing urbanization. Occupancy probability differed among urban green space types for three of six bee species, with values for two native species (M. campanulae and O. pumila) being highest in home gardens and that for the exotic O. caerulescens being highest in community gardens. The combination of occupancy modelling with analysis of habitat variables as an augmentation to detection and abundance-based sampling is suggested to be the best way to ensure that urban habitat management results in the desired outcomes.

  15. Allee effects and colony collapse disorder in honey bees

    USDA-ARS?s Scientific Manuscript database

    We propose a mathematical model to quantify the hypothesis that a major ultimate cause of Colony Collapse Disorder (CCD) in honey bees is the presence of an Allee effect in the growth dynamics of honey bee colonies. In the model, both recruitment of adult bees as well as mortality of adult bees have...

  16. Transcriptional responses in honey bee larvae infected with chalkbrood fungus

    USDA-ARS?s Scientific Manuscript database

    Diseases and other stress factors working synergistically weaken honey bee health and may play a major role in the losses of bee populations in recent years. Among a large number of bee diseases, chalkbrood has been on the rise. We present here the experimental identification of honey bee genes that...

  17. Assessing grooming behavior of Russian honey bees toward Varroa destructor.

    USDA-ARS?s Scientific Manuscript database

    The grooming behavior of Russian bees was compared to Italian bees. Overall, Russian bees had significantly lower numbers of mites than the Italian bees with a mean of 1,937 ± 366 and 5,088 ± 733 mites, respectively. This low mite population in the Russian colonies was probably due to the increased ...

  18. Antiviral Defense Mechanisms in Honey Bees

    PubMed Central

    Brutscher, Laura M.; Daughenbaugh, Katie F.; Flenniken, Michelle L.

    2015-01-01

    Honey bees are significant pollinators of agricultural crops and other important plant species. High annual losses of honey bee colonies in North America and in some parts of Europe have profound ecological and economic implications. Colony losses have been attributed to multiple factors including RNA viruses, thus understanding bee antiviral defense mechanisms may result in the development of strategies that mitigate colony losses. Honey bee antiviral defense mechanisms include RNA-interference, pathogen-associated molecular pattern (PAMP) triggered signal transduction cascades, and reactive oxygen species generation. However, the relative importance of these and other pathways is largely uncharacterized. Herein we review the current understanding of honey bee antiviral defense mechanisms and suggest important avenues for future investigation. PMID:26273564

  19. Virus infections in Brazilian honey bees.

    PubMed

    Teixeira, Erica Weinstein; Chen, Yanping; Message, Dejair; Pettis, Jeff; Evans, Jay D

    2008-09-01

    This work describes the first molecular-genetic evidence for viruses in Brazilian honey bee samples. Three different bee viruses, Acute bee paralysis virus (ABPV), Black queen cell virus (BQCV), and Deformed wing virus (DWV) were identified during a screening of RNAs from 1920 individual adult bees collected in a region of southeastern Brazil that has recently shown unusual bee declines. ABPV was detected in 27.1% of colony samples, while BQCV and DWV were found in 37% and 20.3%, respectively. These levels are substantially lower than the frequencies found for these viruses in surveys from other parts of the world. We also developed and validated a multiplex RT-PCR assay for the simultaneous detection of ABPV, BQCV, and DWV in Brazil.

  20. Hot spots in the bee hive

    NASA Astrophysics Data System (ADS)

    Bujok, Brigitte; Kleinhenz, Marco; Fuchs, Stefan; Tautz, Jürgen

    2002-06-01

    Honeybee colonies (Apis mellifera) maintain temperatures of 35-36°C in their brood nest because the brood needs high and constant temperature conditions for optimal development. We show that incubation of the brood at the level of individual honeybees is done by worker bees performing a particular and not yet specified behaviour: such bees raise the brood temperature by pressing their warm thoraces firmly onto caps under which the pupae develop. The bees stay motionless in a characteristic posture and have significantly higher thoracic temperatures than bees not assuming this posture in the brood area. The surface of the brood caps against which warm bees had pressed their thorax were up to 3.2°C warmer than the surrounding area, confirming that effective thermal transfer had taken place.

  1. Metatranscriptomic analyses of honey bee colonies

    PubMed Central

    Tozkar, Cansu Ö.; Kence, Meral; Kence, Aykut; Huang, Qiang; Evans, Jay D.

    2015-01-01

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World's most important centers of apiculture, harboring five subspecies of Apis mellifera L., approximately 20% of the honey bee subspecies in the world. We use deep ILLUMINA-based RNA sequencing to capture RNA species for the honey bee and a sampling of all non-endogenous species carried by bees. After trimming and mapping these reads to the honey bee genome, approximately 10% of the sequences (9–10 million reads per library) remained. These were then mapped to a curated set of public sequences containing ca. Sixty megabase-pairs of sequence representing known microbial species associated with honey bees. Levels of key honey bee pathogens were confirmed using quantitative PCR screens. We contrast microbial matches across different sites in Turkey, showing new country recordings of Lake Sinai virus, two Spiroplasma bacterium species, symbionts Candidatus Schmidhempelia bombi, Frischella perrara, Snodgrassella alvi, Gilliamella apicola, Lactobacillus spp.), neogregarines, and a trypanosome species. By using metagenomic analysis, this study also reveals deep molecular evidence for the presence of bacterial pathogens (Melissococcus plutonius, Paenibacillus larvae), Varroa destructor-1 virus, Sacbrood virus, and fungi. Despite this effort we did not detect KBV, SBPV, Tobacco ringspot virus, VdMLV (Varroa Macula like virus), Acarapis spp., Tropilaeleps spp. and Apocephalus (phorid fly). We discuss possible impacts of management practices and honey bee subspecies on microbial retinues. The described workflow and curated microbial database will be generally useful for microbial surveys of healthy and declining honey bees. PMID:25852743

  2. Genetic stock identification of Russian honey bees.

    PubMed

    Bourgeois, Lelania; Sheppard, Walter S; Sylvester, H Allen; Rinderer, Thomas E

    2010-06-01

    A genetic stock certification assay was developed to distinguish Russian honey bees from other European (Apis mellifera L.) stocks that are commercially produced in the United States. In total, 11 microsatellite and five single-nucleotide polymorphism loci were used. Loci were selected for relatively high levels of homogeneity within each group and for differences in allele frequencies between groups. A baseline sample consisted of the 18 lines of Russian honey bees released to the Russian Bee Breeders Association and bees from 34 queen breeders representing commercially produced European honey bee stocks. Suitability tests of the baseline sample pool showed high levels of accuracy. The probability of correct assignment was 94.2% for non-Russian bees and 93.3% for Russian bees. A neighbor-joining phenogram representing genetic distance data showed clear distinction of Russian and non-Russian honey bee stocks. Furthermore, a test of appropriate sample size showed a sample of eight bees per colony maximizes accuracy and consistency of the results. An additional 34 samples were tested as blind samples (origin unknown to those collecting data) to determine accuracy of individual assignment tests. Only one of these samples was incorrectly assigned. The 18 current breeding lines were represented among the 2009 blind sampling, demonstrating temporal stability of the genetic stock identification assay. The certification assay will be used through services provided by a service laboratory, by the Russian Bee Breeders Association to genetically certify their stock. The genetic certification will be used in conjunction with continued selection for favorable traits, such as honey production and varroa and tracheal mite resistance.

  3. Hygienic behaviour in Brazilian stingless bees.

    PubMed

    Al Toufailia, Hasan; Alves, Denise A; Bento, José M S; Marchini, Luis C; Ratnieks, Francis L W

    2016-11-15

    Social insects have many defence mechanisms against pests and pathogens. One of these is hygienic behaviour, which has been studied in detail in the honey bee, Apis mellifera Hygienic honey bee workers remove dead and diseased larvae and pupae from sealed brood cells, thereby reducing disease transfer within the colony. Stingless bees, Meliponini, also rear broods in sealed cells. We investigated hygienic behaviour in three species of Brazilian stingless bees (Melipona scutellaris, Scaptotrigona depilis, Tetragonisca angustula) in response to freeze-killed brood. All three species had high mean levels of freeze-killed brood removal after 48 h ∼99% in M. scutellaris, 80% in S. depilis and 62% in T. angustula (N=8 colonies per species; three trials per colony). These levels are greater than in unselected honey bee populations, ∼46%. In S. depilis there was also considerable intercolony variation, ranging from 27% to 100% removal after 2 days. Interestingly, in the S. depilis colony with the slowest removal of freeze-killed brood, 15% of the adult bees emerging from their cells had shrivelled wings indicating a disease or disorder, which is as yet unidentified. Although the gross symptoms resembled the effects of deformed wing virus in the honey bee, this virus was not detected in the samples. When brood comb from the diseased colony was introduced to the other S. depilis colonies, there was a significant negative correlation between freeze-killed brood removal and the emergence of deformed worker bees (P=0.001), and a positive correlation with the cleaning out of brood cells (P=0.0008). This shows that the more hygienic colonies were detecting and removing unhealthy brood prior to adult emergence. Our results indicate that hygienic behaviour may play an important role in colony health in stingless bees. The low levels of disease normally seen in stingless bees may be because they have effective mechanisms of disease management, not because they lack diseases.

  4. Metatranscriptomic analyses of honey bee colonies.

    PubMed

    Tozkar, Cansu Ö; Kence, Meral; Kence, Aykut; Huang, Qiang; Evans, Jay D

    2015-01-01

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World's most important centers of apiculture, harboring five subspecies of Apis mellifera L., approximately 20% of the honey bee subspecies in the world. We use deep ILLUMINA-based RNA sequencing to capture RNA species for the honey bee and a sampling of all non-endogenous species carried by bees. After trimming and mapping these reads to the honey bee genome, approximately 10% of the sequences (9-10 million reads per library) remained. These were then mapped to a curated set of public sequences containing ca. Sixty megabase-pairs of sequence representing known microbial species associated with honey bees. Levels of key honey bee pathogens were confirmed using quantitative PCR screens. We contrast microbial matches across different sites in Turkey, showing new country recordings of Lake Sinai virus, two Spiroplasma bacterium species, symbionts Candidatus Schmidhempelia bombi, Frischella perrara, Snodgrassella alvi, Gilliamella apicola, Lactobacillus spp.), neogregarines, and a trypanosome species. By using metagenomic analysis, this study also reveals deep molecular evidence for the presence of bacterial pathogens (Melissococcus plutonius, Paenibacillus larvae), Varroa destructor-1 virus, Sacbrood virus, and fungi. Despite this effort we did not detect KBV, SBPV, Tobacco ringspot virus, VdMLV (Varroa Macula like virus), Acarapis spp., Tropilaeleps spp. and Apocephalus (phorid fly). We discuss possible impacts of management practices and honey bee subspecies on microbial retinues. The described workflow and curated microbial database will be generally useful for microbial surveys of healthy and declining honey bees.

  5. Hygienic behaviour in Brazilian stingless bees

    PubMed Central

    Alves, Denise A.; Bento, José M. S.; Marchini, Luis C.; Ratnieks, Francis L. W.

    2016-01-01

    ABSTRACT Social insects have many defence mechanisms against pests and pathogens. One of these is hygienic behaviour, which has been studied in detail in the honey bee, Apis mellifera. Hygienic honey bee workers remove dead and diseased larvae and pupae from sealed brood cells, thereby reducing disease transfer within the colony. Stingless bees, Meliponini, also rear broods in sealed cells. We investigated hygienic behaviour in three species of Brazilian stingless bees (Melipona scutellaris, Scaptotrigona depilis, Tetragonisca angustula) in response to freeze-killed brood. All three species had high mean levels of freeze-killed brood removal after 48 h ∼99% in M. scutellaris, 80% in S. depilis and 62% in T. angustula (N=8 colonies per species; three trials per colony). These levels are greater than in unselected honey bee populations, ∼46%. In S. depilis there was also considerable intercolony variation, ranging from 27% to 100% removal after 2 days. Interestingly, in the S. depilis colony with the slowest removal of freeze-killed brood, 15% of the adult bees emerging from their cells had shrivelled wings indicating a disease or disorder, which is as yet unidentified. Although the gross symptoms resembled the effects of deformed wing virus in the honey bee, this virus was not detected in the samples. When brood comb from the diseased colony was introduced to the other S. depilis colonies, there was a significant negative correlation between freeze-killed brood removal and the emergence of deformed worker bees (P=0.001), and a positive correlation with the cleaning out of brood cells (P=0.0008). This shows that the more hygienic colonies were detecting and removing unhealthy brood prior to adult emergence. Our results indicate that hygienic behaviour may play an important role in colony health in stingless bees. The low levels of disease normally seen in stingless bees may be because they have effective mechanisms of disease management, not because they lack

  6. Brood care by male bumble bees

    PubMed Central

    Cameron, Sydney A.

    1985-01-01

    Male Bombus griseocollis (Hymenoptera: Apidae) share in the brood care of nestmates by incubating pupae (usually during the first few days after they emerge as adults). Male posture during incubation of a pupa is identical to that observed for females. Pupae incubated by males were 4°C-6°C above the temperature of unincubated pupae. Although this increase was not as great as that caused by workers or queens, it was an important factor in warming pupae. Incubating males may benefit nestmates incidentally without lowering their own individual fitness. Images PMID:16593608

  7. The endangered Iris atropurpurea (Iridaceae) in Israel: honey-bees, night-sheltering male bees and female solitary bees as pollinators

    PubMed Central

    Watts, Stella; Sapir, Yuval; Segal, Bosmat; Dafni, Amots

    2013-01-01

    Background and Aims The coastal plain of Israel hosts the last few remaining populations of the endemic Iris atropurpurea (Iridaceae), a Red List species of high conservation priority. The flowers offer no nectar reward. Here the role of night-sheltering male solitary bees, honey-bees and female solitary bees as pollinators of I. atropurpurea is documented. Methods Breeding system, floral longevity, stigma receptivity, visitation rates, pollen loads, pollen deposition and removal and fruit- and seed-set were investigated. Key Results The main wild pollinators of this plant are male eucerine bees, and to a lesser extent, but with the potential to transfer pollen, female solitary bees. Honey-bees were found to be frequent diurnal visitors; they removed large quantities of pollen and were as effective as male sheltering bees at pollinating this species. The low density of pollen carried by male solitary bees was attributed to grooming activities, pollen displacement when bees aggregated together in flowers and pollen depletion by honey-bees. In the population free of honey-bee hives, male bees carried significantly more pollen grains on their bodies. Results from pollen analysis and pollen deposited on stigmas suggest that inadequate pollination may be an important factor limiting fruit-set. In the presence of honey-bees, eucerine bees were low removal–low deposition pollinators, whereas honey-bees were high removal–low deposition pollinators, because they removed large amounts into corbiculae and deposited relatively little onto receptive stigmas. Conclusions Even though overall, both bee taxa were equally effective pollinators, we suggest that honey-bees have the potential to reduce the amount of pollen available for plant reproduction, and to reduce the amount of resources available to solitary bee communities. The results of this study have potential implications for the conservation of this highly endangered plant species if hives are permitted inside

  8. The endangered Iris atropurpurea (Iridaceae) in Israel: honey-bees, night-sheltering male bees and female solitary bees as pollinators.

    PubMed

    Watts, Stella; Sapir, Yuval; Segal, Bosmat; Dafni, Amots

    2013-03-01

    The coastal plain of Israel hosts the last few remaining populations of the endemic Iris atropurpurea (Iridaceae), a Red List species of high conservation priority. The flowers offer no nectar reward. Here the role of night-sheltering male solitary bees, honey-bees and female solitary bees as pollinators of I. atropurpurea is documented. Breeding system, floral longevity, stigma receptivity, visitation rates, pollen loads, pollen deposition and removal and fruit- and seed-set were investigated. The main wild pollinators of this plant are male eucerine bees, and to a lesser extent, but with the potential to transfer pollen, female solitary bees. Honey-bees were found to be frequent diurnal visitors; they removed large quantities of pollen and were as effective as male sheltering bees at pollinating this species. The low density of pollen carried by male solitary bees was attributed to grooming activities, pollen displacement when bees aggregated together in flowers and pollen depletion by honey-bees. In the population free of honey-bee hives, male bees carried significantly more pollen grains on their bodies. Results from pollen analysis and pollen deposited on stigmas suggest that inadequate pollination may be an important factor limiting fruit-set. In the presence of honey-bees, eucerine bees were low removal-low deposition pollinators, whereas honey-bees were high removal-low deposition pollinators, because they removed large amounts into corbiculae and deposited relatively little onto receptive stigmas. Even though overall, both bee taxa were equally effective pollinators, we suggest that honey-bees have the potential to reduce the amount of pollen available for plant reproduction, and t