Combined stress from parasites, pesticides and lack of flowers drives bee declines

Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined, bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple, interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future

Could fungal infection make ant societies more open?

Ant colonies are a highly rewarding target for many pathogens and parasites and they also host various species of social parasites that exploit their social system. Myrmica ants seem to be particularly susceptible to exploitation by social parasites and by ecto- and endoparasites. Also many Myrmica colonies frequently adopt unrelated gynes, which can be interpreted as temporary social parasites. Myrmica scabrinodis is a common host of the ectoparasitic fungus Rickia wasmannii and its colonies are used by socially parasitic butterfly larvae of Maculinea genus. In some M. scabrinodis populations both R. wasmannii and Maculinea butterflies occur together using the same host colonies. In our study we used such population to check whether fungal infection change the threshold of acceptance of social parasites and unrelated queens by ants and make colonies more open for strangers. For this purpose we performed experiments during which we tested how infection by R. wasmannii affects frequency and time of Maculinea larva adoption and adoption of unrelated ant queens. We also carried out aggression tests where we used M. scabrinodis workers originating from infected and uninfected colonies to check if fungal infection influences the amount of adverse reactions. Our preliminary results indicate that ants infected by the fungus are more readily adopting social parasites, while being less aggressive towards foreign queens. Thus, infected colonies could be more prone for social parasitism

Comparing weight dynamics between urban and rural honey bee colonies in Latvia

Received: January 16th, 2023 ; Accepted: April 8th, 2023 ; Published: April 17th, 2023 ; Correspondence: [email protected] is an important agricultural industry in Latvia, which has an area of 64,589 km2 and is largely mixed forest. The natural foraging base does not provide the honey yield evenly throughout the whole season, thus the average honey yield in Latvia is about 20 kg per colony. The objective of this research was to compare the weight dynamics of colonies placed in rural and urban environments. As urban beekeeping is becoming more popular, it is important to understand whether there are enough foraging resources within the city for the bee colonies. To do this, the weight changes of ten honey bee colonies was remotely monitored and analysed during the summer period. Five colonies were located in the rural environment in Vecauce and five in the urban environment in Jelgava city. Colonies were assessed using the precision beekeeping approach and developed scale systems. It was concluded that for rural colonies in Vecauce, the main weight increase occurred in June - from 41.02 to 54.68 kg - which resulted in 94% of the total increase for the summer period. Data analysis from the urban apiary revealed that colonies increase weight during the entire monitoring period, indicating that there are foraging resources available throughout the summer period within the city

Searching for nests of the invasive Asian hornet (Vespa velutina) using radio-telemetry

This is the final version of the article. Available from the publisher via the DOI in this recordAsian hornets (Vespa velutina) are voracious predators of bees, and are the latest emerging threat to managed and wild pollinator populations in Europe. To prevent establishment or reduce the rate of spread of V. velutina, early detection and destruction of nests is considered the only option. Detection is difficult as their nests are well hidden and flying hornets are difficult to follow over long distances. We address this challenge by tracking individual V. velutina workers flying back to their nests using radio telemetry for the first time, finding five previously undiscovered nests, up to 1.33 km from hornet release points. Hornets can fly with 0.28 g tags if the tag:hornet ratio is less than 0.8. This method offers a step-change in options to tackle the spread of this invader, providing an efficient means of finding V. velutina nests in complex environments to manage this emerging threat to pollinators.We thank Olivier Bonnard for discussions, sourcing materials, and advice on locating foraging V. velutina workers at INRA Bordeaux-Aquitaine. We also thank members of Jersey Beekeeping Association for their assistance in catching V. velutina workers in Jersey. The work was funded by a Defra research project grant (PH0532), with additional support by the States of Jersey Department of Environment and generous philanthropic donations by the South West Beekeeping Associations’ Forum (SWBKF), Somerset Beekeeping Association, Dorset Beekeeping Association, Cornwall Beekeeping Association, West Cornwall Beekeeping Association, Devon Beekeeping Association, Bournemouth & South Dorset Beekeeping Association, and B.J. Sherriff. We are grateful to INRA Bordeaux-Aquitaine, States of Jersey Department of Environment, and Durrell Wildlife Park for their welcome and permission to use facilities at their institutions

Bumblebee foraging rhythms under the midnight sun measured with radiofrequency identification

<p>Abstract</p> <p>Background</p> <p>In the permanent daylight conditions north of the Arctic circle, there is a unique opportunity for bumblebee foragers to maximise intake, and therefore colony growth, by remaining active during the entire available 24-h period. We tested the foraging rhythms of bumblebee (<it>Bombus terrestris </it>and <it>B. pascuorum</it>) colonies in northern Finland during the summer, when the sun stays above the horizon for weeks. We used fully automatic radio-frequency identification to monitor the foraging activity of more than 1,000 workers and analysed their circadian foraging rhythms.</p> <p>Results</p> <p>Foragers did not use the available 24-h foraging period but exhibited robust diurnal rhythms instead. A mean of 95.2% of the tested <it>B. terrestris </it>workers showed robust diurnal rhythms with a mean period of 23.8 h. Foraging activity took place mainly between 08:00 and 23:00, with only low or almost no activity during the rest of the day. Activity levels increased steadily during the morning, reached a maximum around midday and decreased again during late afternoon and early evening. Foraging patterns of native <it>B. pascuorum </it>followed the same temporal organisation, with the foraging activity being restricted to the period between 06:00 and 22:00.</p> <p>Conclusions</p> <p>The results of the present study indicate that the circadian clock of the foragers must have been entrained by some external cue, the most prominent being daily cycles in light intensity and temperature. Daily fluctuations in the spectral composition of light, especially in the UV range, could also be responsible for synchronising the circadian clock of the foragers under continuous daylight conditions.</p

Honey from Stingless Bee as Indicator of Contamination with Metals

Melipona scutellaris (Apidae, Meliponini) is one of the main species of stingless bees used in beekeeping in the Northeast of Brazil. We examined the honey from M. scutellaris as an indicator to evaluate the levels of metals at sampling sites subject to a broad spectrum of environmental pollutants. The collections were carried out in the urban-industrial area of Salvador, Bahia and the metropolitan region. Samples (n= 58) were submitted to the nitroperchloric digestion procedure. We used the inductively coupled plasma optical emission spectrometry technique (ICP OES) to determine the concentration of metals (Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb and Zn) in the samples. The studied metals were detected among the samples, which presented tolerable levels according to current Brazilian legislation and recommendations from the World Health Organization (WHO), except for Cr, which presented mean values higher than the threshold for all sampling sites. The detection of the analyzed metals indicates that the honey of M. scutellaris is a useful tool to evaluate the presence of environmental contaminants; therefore, it can be considered a good indicator of environmental contamination for monitoring a particular region and preventing issues due to the release of metals into the environment

Biomonitoring for wide area surveying in landmine detection using honeybees and optical sensing

This project has received funding from NATO Science for Peace & Security under grant agreement MYP G5355, and the Engineering and Physical Sciences Research Council under EP/K503940/1.Humanitarian demining is a worldwide effort and the range of climates and environments prevent any one detection method being suitable for all sites, so more tools are required for safe and efficient explosives sensing. Landmines emit a chemical flux over time, and honeybees can collect the trace residues of explosives (as particles or as vapour) on their body hairs. This capability was exploited using a passive method allowing the honeybees to freely forage in a mined area, where trace explosives present in the environment stuck to the honeybee body, which were subsequently transferred onto an adsorbent material for analysis by a fluorescent polymer sensor. Potential false positive sources were investigated, namely common bee pheromones, the anti-varroa pesticide Amitraz, and the environment around a clean apiary, and no significant response was found to any from the sensor. The mined site gave a substantial response in the optical sensor films, with quenching efficiencies of up to 38%. A model was adapted to estimate the mass of explosives returned to the colony, which may be useful for estimating the number of mines in a given area.PostprintPeer reviewe

Planning For Pollinators, Encouraging Biodiversity For Agriculture Resiliency

Pollinators are essential to food production globally. Without them, the production of food becomes increasingly difficult, time consuming, and costly. Unfortunately, due to the rapid changes to our earth\u27s physical and climatic structure millions of species are becoming classified as threatened, endangered or extinct. Among these declining species are pollinating insects such as Aphis mellifera (honeybee) and other native species. This is due to a phenomenon known as colony collapse disorder (CCD) and other native bees. The decline indicates that the future habitability of earth may be in jeopardy. The solution to this crisis is to expand the habitat of native bees into our existing infrastructure, connecting the pollinator dependent crops with a network of biodiverse habitat. This will greatly improve the existing agricultural industries resiliency towards change. Thus, ensuring that California can be economically prosperous while continuing to feed the globe. The Sacramento Valley is one location which is ideal to develop such a network of native pollinator habitat due to its reliance on the agriculture industry and favorable environmental conditions