Risk factors associated with honey bee colony loss in apiaries in Galicia, NW Spain

A cross-sectional study was carried out in Galicia, NW Spain, in order to estimate the magnitude of honey bee colony losses and to identify potential risk factors involved. A total of 99 samples from 99 apiaries were collected in spring using simple random sampling. According to international guidelines, the apiaries were classified as affected by colony loss or asymptomatic. Each sample consisted of worker bees, brood and comb-stored pollen. All worker bees and brood samples were analysed individually in order to detect the main honey bee pathogens. Moreover, the presence of residues of the most prevalent agrotoxic insecticides and acaricides was assessed in comb-stored pollen. The general characteristics of the apiaries and sanitary information regarding previous years was evaluated through questionnaires, while the vegetation surrounding the apiaries sampled was assessed by palynological analysis of comb-stored pollen. The colony loss prevalence was 53.5% (CI95%=43.2-63.9) and Nosema ceranae was found to be the only risk factor strongly associated with colony loss. The decision tree also pointed out the impact of the Varroa mite presence while variables such as apiary size, the incorrect application of Varroa mite treatments, and the presence of Acarapis woodi and Kashmir bee virus (KBV) were identified as possible co-factors.

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Imidacloprid Decreases Honey Bee Survival Rates but Does Not Affect the Gut Microbiome

Applied and Environmental Microbiology ◽

10.1128/aem.00545-18 ◽

2018 ◽

Vol 84 (13) ◽

Cited By ~ 26

Author(s):

Kasie Raymann ◽

Erick V. S. Motta ◽

Catherine Girard ◽

Ian M. Riddington ◽

Jordan A. Dinser ◽

...

Keyword(s):

Honey Bee ◽

Gut Microbiome ◽

Honey Bees ◽

Microbiome Composition ◽

Susceptibility To Infection ◽

Bee Colony ◽

Colony Loss ◽

Honey Bee Colony ◽

The Impact

ABSTRACT Accumulating evidence suggests that pesticides have played a role in the increased rate of honey bee colony loss. One of the most commonly used pesticides in the United States is the neonicotinoid imidacloprid. Although the primary mode of action of imidacloprid is on the insect nervous system, it has also been shown to cause changes in insects' digestive physiology and alter the microbiota of Drosophila melanogaster larvae. The honey bee gut microbiome plays a major role in bee health. Although many studies have shown that imidacloprid affects honey bee behavior, its impact on the microbiome has not been fully elucidated. Here, we investigated the impact of imidacloprid on the gut microbiome composition, survivorship, and susceptibility to pathogens of honey bees. Consistent with other studies, we show that imidacloprid exposure results in an elevated mortality of honey bees in the hive and increases the susceptibility to infection by pathogens. However, we did not find evidence that imidacloprid affects the gut bacterial community of honey bees. Our in vitro experiments demonstrated that honey bee gut bacteria can grow in the presence of imidacloprid, and we found some evidence that imidacloprid can be metabolized in the bee gut environment. However, none of the individual bee gut bacterial species tested could metabolize imidacloprid, suggesting that the observed metabolism of imidacloprid within in vitro bee gut cultures is not caused by the gut bacteria. Overall, our results indicate that imidacloprid causes increased mortality in honey bees, but this mortality does not appear to be linked to the microbiome. IMPORTANCE Growing evidence suggests that the extensive use of pesticides has played a large role in the increased rate of honey bee colony loss. Despite extensive research on the effects of imidacloprid on honey bees, it is still unknown whether it impacts the community structure of the gut microbiome. Here, we investigated the impact of imidacloprid on the gut microbiome composition, survivorship, and susceptibility to pathogens of honey bees. We found that the exposure to imidacloprid resulted in an elevated mortality of honey bees and increased the susceptibility to infection by opportunistic pathogens. However, we did not find evidence that imidacloprid affects the gut microbiome of honey bees. We found some evidence that imidacloprid can be metabolized in the bee gut environment in vitro , but because it is quickly eliminated from the bee, it is unlikely that this metabolism occurs in nature. Thus, imidacloprid causes increased mortality in honey bees, but this does not appear to be linked to the microbiome.

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Monitoring of Honey Bee Colony Losses: A Special Issue

Diversity ◽

10.3390/d12100403 ◽

2020 ◽

Vol 12 (10) ◽

pp. 403

Author(s):

Aleš Gregorc

Keyword(s):

Honey Bee ◽

Abiotic Factors ◽

Special Issue ◽

Colony Losses ◽

Colony Management ◽

Bee Colony ◽

Honey Bee Colony ◽

The Impact ◽

Bee Colonies ◽

Honey Bee Colony Losses

In recent decades, independent national and international research programs have revealed possible reasons for the death of managed honey bee colonies worldwide. Such losses are not due to a single factor, but instead are due to highly complex interactions between various internal and external influences, including pests, pathogens, honey bee stock diversity, and environmental change. Reduced honey bee vitality and nutrition, exposure to agrochemicals, and quality of colony management contribute to reduced colony survival in beekeeping operations. Our Special Issue (SI) on ‘’Monitoring of Honey Bee Colony Losses’’ aims to address specific challenges facing honey bee researchers and beekeepers. This SI includes four reviews, with one being a meta-analysis that identifies gaps in the current and future directions for research into honey bee colonies mortalities. Other review articles include studies regarding the impact of numerous factors on honey bee mortality, including external abiotic factors (e.g., winter conditions and colony management) as well as biotic factors such as attacks by Vespa velutina and Varroa destructor.

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Austrian COLOSS Survey of Honey Bee Colony Winter Losses 2018/19 and Analysis of Hive Management Practices

Diversity ◽

10.3390/d12030099 ◽

2020 ◽

Vol 12 (3) ◽

pp. 99 ◽

Cited By ~ 4

Author(s):

Hannes Oberreiter ◽

Robert Brodschneider

Keyword(s):

Honey Bee ◽

Management Practices ◽

Favourable Effect ◽

Winter Mortality ◽

Colony Losses ◽

Bee Colony ◽

Honey Bee Colony ◽

Colony Survival ◽

The Impact ◽

Loss Rates

We conducted a citizen science survey on overwinter honey bee colony losses in Austria. A total of 1534 beekeepers with 33,651 colonies reported valid loss rates. The total winter loss rate for Austria was 15.2% (95% confidence interval: 14.4–16.1%). Young queens showed a positive effect on colony survival and queen-related losses. Observed queen problems during the season increased the probability of losing colonies to unsolvable queen problems. A notable number of bees with crippled wings during the foraging season resulted in high losses and could serve as an alarm signal for beekeepers. Migratory beekeepers and large operations had lower loss rates than smaller ones. Additionally, we investigated the impact of several hive management practices. Most of them had no significant effect on winter mortality, but purchasing wax from outside the own operation was associated with higher loss rates. Colonies that reported foraging on maize and late catch crop fields or collecting melezitose exhibited higher loss rates. The most common Varroa destructor control methods were a combination of long-term formic acid treatment in summer and oxalic acid trickling in winter. Biotechnical methods in summer had a favourable effect on colony survival.

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Short communication. The detection of Israeli Acute Paralysis virus (IAPV), fipronil and imidacloprid in professional apiaries are not related with massive honey bee colony loss in Spain

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2010083-1262 ◽

2010 ◽

Vol 8 (3) ◽

pp. 658 ◽

Cited By ~ 9

Author(s):

E. Garrido-Bailón ◽

R. Martín-Hernández ◽

J. Bernal ◽

J .L. Bernal ◽

A. Martínez-Salvador ◽

...

Keyword(s):

Honey Bee ◽

Short Communication ◽

Israeli Acute Paralysis Virus ◽

Bee Colony ◽

Colony Loss ◽

Honey Bee Colony ◽

Paralysis Virus

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Ukraine is Moving Forward from “Undiscovered Honey Land” to Active Participation in International Monitoring of Honey Bee Colony Losses

Bee World ◽

10.1080/0005772x.2018.1554279 ◽

2019 ◽

Vol 96 (2) ◽

pp. 50-54 ◽

Cited By ~ 2

Author(s):

Mariia M. Fedoriak ◽

Per K. Angelstam ◽

Oleksandr M. Kulmanov ◽

Lesia I. Tymochko ◽

Svitlana S. Rudenko ◽

...

Keyword(s):

Honey Bee ◽

Active Participation ◽

Colony Losses ◽

Bee Colony ◽

International Monitoring ◽

Honey Bee Colony ◽

Honey Bee Colony Losses

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A survey of managed honey bee colony losses in the Republic of South Africa–2009 to 2011

Journal of Apicultural Research ◽

10.3896/ibra.1.53.1.03 ◽

2014 ◽

Vol 53 (1) ◽

pp. 35-42 ◽

Cited By ~ 75

Author(s):

Christian W W Pirk ◽

Hannelie Human ◽

Robin M Crewe ◽

Dennis vanEngelsdorp

Keyword(s):

South Africa ◽

Honey Bee ◽

Colony Losses ◽

Bee Colony ◽

Honey Bee Colony ◽

The Republic ◽

Honey Bee Colony Losses

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Correlations between land covers and honey bee colony losses in a country with industrialized and rural regions

The Science of The Total Environment ◽

10.1016/j.scitotenv.2015.05.128 ◽

2015 ◽

Vol 532 ◽

pp. 1-13 ◽

Cited By ~ 29

Author(s):

Antoine Clermont ◽

Michael Eickermann ◽

François Kraus ◽

Lucien Hoffmann ◽

Marco Beyer

Keyword(s):

Honey Bee ◽

Rural Regions ◽

Colony Losses ◽

Bee Colony ◽

Honey Bee Colony ◽

Land Covers ◽

Honey Bee Colony Losses

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A mutualistic symbiosis between a parasitic mite and a pathogenic virus undermines honey bee immunity and health

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1523515113 ◽

2016 ◽

Vol 113 (12) ◽

pp. 3203-3208 ◽

Cited By ~ 101

Author(s):

Gennaro Di Prisco ◽

Desiderato Annoscia ◽

Marina Margiotta ◽

Rosalba Ferrara ◽

Paola Varricchio ◽

...

Keyword(s):

Honey Bee ◽

Stress Factors ◽

Colony Losses ◽

Viral Pathogen ◽

Deformed Wing Virus ◽

Mutualistic Symbiosis ◽

Bee Colony ◽

Parasitic Mite ◽

Honey Bee Colony ◽

Honey Bee Colony Losses

Honey bee colony losses are triggered by interacting stress factors consistently associated with high loads of parasites and/or pathogens. A wealth of biotic and abiotic stressors are involved in the induction of this complex multifactorial syndrome, with the parasitic mite Varroa destructor and the associated deformed wing virus (DWV) apparently playing key roles. The mechanistic basis underpinning this association and the evolutionary implications remain largely obscure. Here we narrow this research gap by demonstrating that DWV, vectored by the Varroa mite, adversely affects humoral and cellular immune responses by interfering with NF-κB signaling. This immunosuppressive effect of the viral pathogen enhances reproduction of the parasitic mite. Our experimental data uncover an unrecognized mutualistic symbiosis between Varroa and DWV, which perpetuates a loop of reciprocal stimulation with escalating negative effects on honey bee immunity and health. These results largely account for the remarkable importance of this mite–virus interaction in the induction of honey bee colony losses. The discovery of this mutualistic association and the elucidation of the underlying regulatory mechanisms sets the stage for a more insightful analysis of how synergistic stress factors contribute to colony collapse, and for the development of new strategies to alleviate this problem.

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