scholarly journals Seasonal Changes in Size and Mite-Prevalence of a Bee Colony Exposed to Dinotefuran via Pollen Paste and Damaged by Varroa Mites

2020 ◽  
Author(s):  
Toshiro Yamada
Keyword(s):  
Seasonal Changes ◽  
Residual Effect ◽  
Farm Work ◽  
Bee Colony ◽  
Average Intake ◽  
Insecticide Activity ◽  
Colony Collapse ◽  
Bee Colonies ◽  
Mite Prevalence

Neonicotinoids, such as dinotefuran (DF), have caused a variety of problems, such as massive loss and winter failure of the bee colony, as a price for the benefit of reducing farm work, because it continues to maintain a high insecticide activity over a long period of time. In this study, a field experiment was conducted for about six months to investigate the effects of DF on bee colonies damaged by Varroa mites. This study examined the long-term changes in such as the size of bee colonies, the intake of sugar syrup (SS), intake of pollen paste (PP), which is a vehicle for administering DF, the intake of DF, the mite-prevalence of bees and the inside and outside temperatures of hive-boxes. The variation width of the inner temperature of the hive-box is less than that of the ambient temperature (Ta). The inner temperature of the hive-box is adjusted with about 30 ℃ of Ta as the boundary. If Ta is lower than 30 ℃, the inner temperature of the box is higher than Ta, and if Ta is higher than 30 ℃, it is lower than Ta. The temperature variation width of the DF-exposed colony is greater than that of the control colony. The average intake of SS per bee per day of the DF-exposed colony is more than that of the control colony. The average intake of PP per bee per day of the DF-exposed colony is almost equal to that of the control colony. These results suggest that bees do not avoid DF, and ingest PP without distinction between toxic and pesticide-free. In the period from the start of DF administration to the colony extinction, the intake of DF per colony is about 865 µg/colony, the intake per bee is 14 ng/bee, and the intake per bee per day is less than 0.1 ng/bee/day in this work. These intakes are much lower than the previous ones (60-65 ng/bee, 0.27-2.32 ng/bee/day). These discrepancies may be because attacks of mites and Japanese giant hornets hastened the colony collapse. Seasonal changes in mite-prevalence of honeybees is approximately the same regardless of the bee colonies. At the end of August (the start of attacks by Japanese giant hornets), the mite-prevalence will increase rapidly. Even if the number of bees damaged by mites turns to decrease, the mite-prevalence will continue to increase, with approaching 100% before bee colonies become extinct. In this study, it was found that the bee colony was collapsed by the intake of a smaller amount of DF due to the synergistic effect of DF and mite-damage. To prevent a bee colony collapse, not only to make an effort to minimalize the adverse effect on the bee colony of neonicotinoids such as DF with long-term residual effect and high insecticide properties, it is necessary to reduce the damage of mites as much as possible, while considering the synergistically adverse effects of neonicotinoids and miticides.

scholarly journals Comparison of long-term changes in size and longevity of bee colonies in mid-west Japan and Maui with and without exposure to pesticide, cold winters, and mites

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9505
Author(s):  
Toshiro Yamada ◽  
Kazuko Yamada
Keyword(s):  
Seasonal Changes ◽  
Field Experiments ◽  
Point Of View ◽  
The Other ◽  
Extended Longevity ◽  
Neonicotinoid Pesticides ◽  
And Control ◽  
Bee Colonies ◽  
Term Field

Four long-term field experiments in mid-west Japan (Shika) made it clear that extinction of colonies exposed to neonicotinoid was much higher than for colonies exposed to organophosphates. The incidence of hive death for of organophosphate-exposed and control (pesticide-free) colonies was similar. We conducted a field experiment in Maui for 271 days using the same pesticides (dinotefuran: 0.2 ppm, clothianidin: 0.08 ppm, fenitrothion: 1 ppm) as used in Shika with the honeybee, Apis mellifera, colonies without mites. Numbers of adult bees, capped brood, mites and other hive parameters were accurately counted on photographs of combs and on the inside of the hives. All six neonicotinoid (dinotefuran & clothianidin)-exposed colonies failed during the experiment. One of three organophosphate (fenitrothion)-exposed colonies and one of the three control colonies also failed. The findings from Maui, where colonies displayed no mites, provides evidence from Shika, with mites, that neonicotinoids are more hazardous to honeybee colonies than organophosphates. The apparent longevity of honeybee colonies on Maui was estimated by numbers of adult bees and capped brood using a mathematical model previously proposed. Seasonal changes in longevity on Maui differ greatly from changes at Shika, the latter showing distinct seasonal variation. Longevity on Maui remains nearly constant throughout the year with wide variations. At Shika, it increases drastically in winter, by six- to ten fold more than the other seasons. Differences seem to depend on the existence of cold winters and the length of flowering seasons. In a perpetually hospitable environment, small changes in conditions can be sensitively reflected in apparent longevity. Examining wide variations in apparent longevity that are seemingly incoherent, we recognized several differences in apparent longevity between neonicotinoid-exposed and organophosphate-exposed colonies: The colony that failed in after organophosphate-exposure colony group exhibited the longest apparent longevity and the fewest number of newly capped brood, as also was the case in control colonies. Extended longevity when few brood are newly produced is reasonable to maintain the colony from a physiological point of view. Extension of apparent longevity is not seen in neonicotinoid-exposed colonies when the number of newly capped brood is fewer. This finding suggests that neonicotinoid pesticides may inhibit normal apian physiology.

Residual effect of long-term applications of farmyard manure to silage maize

1990 ◽  
Vol 26 (1-3) ◽  
pp. 249-252 ◽  
Author(s):  
K. Dilz ◽  
J. Postmus ◽  
W. H. Prins
Keyword(s):  
Farmyard Manure ◽  
Residual Effect ◽  
Silage Maize

scholarly journals Sublethal concentrations of clothianidin affect honey bee colony growth and hive CO2 concentration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
William G. Meikle ◽  
John J. Adamczyk ◽  
Milagra Weiss ◽  
Janie Ross ◽  
Chris Werle ◽  
...  
Keyword(s):  
Honey Bee ◽  
Pesticide Exposure ◽  
Co2 Concentration ◽  
Colony Growth ◽  
Control Group ◽  
Brood Production ◽  
Weight Losses ◽  
Bee Colony ◽  
The Impact ◽  
Bee Colonies

AbstractThe effects of agricultural pesticide exposure upon honey bee colonies is of increasing interest to beekeepers and researchers, and the impact of neonicotinoid pesticides in particular has come under intense scrutiny. To explore potential colony-level effects of a neonicotinoid pesticide at field-relevant concentrations, honey bee colonies were fed 5- and 20-ppb concentrations of clothianidin in sugar syrup while control colonies were fed unadulterated syrup. Two experiments were conducted in successive years at the same site in southern Arizona, and one in the high rainfall environment of Mississippi. Across all three experiments, adult bee masses were about 21% lower among colonies fed 20-ppb clothianidin than the untreated control group, but no effects of treatment on brood production were observed. Average daily hive weight losses per day in the 5-ppb clothianidin colonies were about 39% lower post-treatment than in the 20-ppb clothianidin colonies, indicating lower consumption and/or better foraging, but the dry weights of newly-emerged adult bees were on average 6–7% lower in the 5-ppb group compared to the other groups, suggesting a nutritional problem in the 5-ppb group. Internal hive CO2 concentration was higher on average in colonies fed 20-ppb clothianidin, which could have resulted from greater CO2 production and/or reduced ventilating activity. Hive temperature average and daily variability were not affected by clothianidin exposure but did differ significantly among trials. Clothianidin was found to be, like imidacloprid, highly stable in honey in the hive environment over several months.

scholarly journals Effects of exposure of honey bee colonies to neonicotinoid seed–treated maize crops

2013 ◽  
Vol 57 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Krystyna Pohorecka ◽  
Piotr Skubida ◽  
Piotr Semkiw ◽  
Artur Miszczak ◽  
Dariusz Teper ◽  
...  
Keyword(s):  
Zea Mays ◽  
Honey Bee ◽  
High Specificity ◽  
Negative Effects ◽  
Term Survival ◽  
Pollen Loads ◽  
Modified Quechers ◽  
Specificity And Sensitivity ◽  
Bee Colonies

Abstract The effects to honeybee colonies (Apis mellifera L.) during and after exposure to flowering maize (Zea mays L.), grown from seeds coated with clothianidin and imidacloprid was assessed in field-realistic conditions. The experimental maize crops were adjacent to the other flowering agriculture plants. Honey bee colonies were placed in three differently protected maize fields throughout the blooming period, and thereafter they were transferred to a stationary apiary. Samples of pollen loads, bee bread, and adult bees were collected and analyzed for neonicotinoid residues. To ensure high specificity and sensitivity of detection of the analyzed pesticides, a modified QuEChERS extraction method and liquid chromatography coupled with tandem mass spectrometry were used. Clothianidin was detected only in the samples of pollen loads. Their residue levels ranged from 10.0 to 41.0 ng/g (average 27.0 ng/g). Imidacloprid was found in no investigated sample. No negative effects of neonicotinoid seed-treated maize on the development and long-term survival of honey bee colonies were observed. The low proportion of Zea mays pollen in total bee-collected pollen during the maize flowering period was noted. The findings suggest that maize plants are less attractive forage for honey bees than phacelia (Phacelia tanacetifolia Benth.), buckwheat (Fagopyrum Mill.), white clover (Trifolium repens L.), goldenrod (Solidago L.), and vegetation from Brassicaceae family. The results indicate a possibility of reducing the risk of bees being exposed to the toxic effect of insecticidal dusts dispersed during maize sowing by seeding, in the areas surrounding maize crops, plants that bloom later in the year.

scholarly journals Comparison and assessment of large-scale surface temperature in climate model simulations

2019 ◽  
Vol 5 (1) ◽  
pp. 67-85
Author(s):  
Raquel Barata ◽  
Raquel Prado ◽  
Bruno Sansó
Keyword(s):  
Surface Temperature ◽  
Seasonal Changes ◽  
Large Scale ◽  
Climate Model ◽  
Internal Variability ◽  
Temperature Variability ◽  
Data Driven ◽  
Model Simulations ◽  
Climate Model Simulations

Abstract. We present a data-driven approach to assess and compare the behavior of large-scale spatial averages of surface temperature in climate model simulations and in observational products. We rely on univariate and multivariate dynamic linear model (DLM) techniques to estimate both long-term and seasonal changes in temperature. The residuals from the DLM analyses capture the internal variability of the climate system and exhibit complex temporal autocorrelation structure. To characterize this internal variability, we explore the structure of these residuals using univariate and multivariate autoregressive (AR) models. As a proof of concept that can easily be extended to other climate models, we apply our approach to one particular climate model (MIROC5). Our results illustrate model versus data differences in both long-term and seasonal changes in temperature. Despite differences in the underlying factors contributing to variability, the different types of simulation yield very similar spectral estimates of internal temperature variability. In general, we find that there is no evidence that the MIROC5 model systematically underestimates the amplitude of observed surface temperature variability on multi-decadal timescales – a finding that has considerable relevance regarding efforts to identify anthropogenic “fingerprints” in observational surface temperature data. Our methodology and results present a novel approach to obtaining data-driven estimates of climate variability for purposes of model evaluation.

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