Nav: Home

Field trial with neonicotinoids: Honeybees are much more robust than bumblebees

April 23, 2019

The insecticide clothianidin affects different species of bees in different ways. While it has no demonstrably negative effect on honeybees, it disrupts the growth of bumblebees and threatens the survival of entire colonies. However, the insecticide does not make either species more susceptible to diseases and pathogens, as a massive field study in Sweden shows. The latest findings were published in the renowned journal "Nature Communications".

The insecticide clothianidin affects different species of bees in different ways. While it has no demonstrably negative effect on honeybees, it disrupts the growth of bumble bees and threatens the survival of entire colonies. However, the insecticide does not make either species more susceptible to diseases and pathogens, as a massive field study in Sweden shows. The international team, including scientists from Martin Luther University Halle-Wittenberg (MLU) and the Swedish University of Agricultural Sciences, reports its latest findings in the renowned journal "Nature Communications".

Data for the study have been taken from a unique research project in southern Sweden. In 2013, 96 honeybee colonies were placed in oilseed rape fields where the seeds of the plants had previously been either treated or not treated with clothianidin. The researchers closely observed how the colonies developed, looked for typical pathogens, and analysed the pollen collected by the honeybees. One year later, the experiment was repeated with a subset of the honeybee colonies of the first year. "Most of the previous studies examining the negative effects of neonicotinoids on bees were conducted in the laboratory. The aim of this project was to clarify whether the lab results could be confirmed in the field," explains Julia Osterman, the first author of the study who is doing her PhD at the Institute of Biology at MLU and the Helmholtz Centre for Environmental Research (UFZ). The large-scale project was led by Dr Maj Rundlöf from the University of Lund in Sweden.

In 2015, the research team caused a sensation when its first paper was published in the journal "Nature". The paper described how the insecticide negatively impacted wild bees. In the new study, the team has augmented its previous findings with new details. One focus of the new study and a parallel - though only one-year-long - study on bumblebees was to find out whether pesticides make bees more susceptible to disease. The researchers found no evidence of this. Instead, the colonies near treated sites acquired fewer pathogens over time even though the pollen they collected contained considerable amounts of clothianidin, while pollen collected from control colonies were practically free of the neonicotinoid.

The size of the honeybee colonies also remained constant. "Because they are so large, honeybee colonies can compensate for negative effects on individual bees much better than solitary bees or bumble bees," says Osterman. But the situation was different for bumble bees: If they were placed near fields treated with clothianidin, their offspring were not only much smaller, the colonies produced considerably fewer queens and male drones. "Since only newborn bumblebee queens survive the winter, the negative influence on their numbers is particularly worrying," explains Dimitry Wintermantel from the French Institute of Agricultural Sciences INRA, who also played an instrumental role in the new study.

The new results not only confirm the analyses of the original field study. According to the researchers, they also demonstrate to researchers how important wild bee trials are in the approval process for pesticides. At the same time, the study suggests that it can be difficult to transfer results from lab tests to real conditions in the field. Both could mean that the risk assessment for pesticides might need to be changed. In 2018, the European Union banned the outdoor use of three out of five neonicotinoids, including clothianidin, due to their harmful effects on bees. This has meant farmers now have to resort to alternative pesticides. "However, it is still unclear what impact they have on bees and how the cultivation of mass crops, such as rapeseed, is changing in Europe as a result of the ban," Osterman concludes.
-end-
More information:

Rundlöf et al. Seed coating with a neonicotinoid insecticide negatively affects wild bees. Nature (2015). doi: 10.1038/nature14420

Wintermantel et al. Field-level clothianidin exposure affects bumblebees but generally not their pathogens. Nature Communications (2018). doi: 10.1038/s41467-018-07914-3Funding for the field project was provided by the Swedish Civil Contingencies Agency (to T.R.-P., R.B. and H.G.S.), the Swedish Research Council VR (grant no 330-2014-6439) (to M.R.), and the Swedish Research Council FORMAS (to H.G.S. and R.B.). Parts of the pathological study were financed internally at SLU. The study of individual exposure and stability of pesticides in bees was financed by the Swedish Environmental Protection Agency (to O.J.).

Martin-Luther-Universität Halle-Wittenberg

Related Pesticides Articles:

Nanozymes -- efficient antidote against pesticides
Members of the Faculty of Chemistry of the Lomonosov Moscow State University have developed novel nanosized agents -- nanozymes, which could be used as efficient protective and antidote modalities against the impact of neurotoxic organophosphorous compounds: pesticides and chemical warfare agents.
Study examines pesticides' impact on wood frogs
A new study looks at how neonicotinoid pesticides affect wood frogs, which use surface waters in agricultural environments to breed and reproduce.
USDA announces $1.8 million for research on next generation pesticides
The US Department of Agriculture's (USDA) National Institute of Food and Agriculture (NIFA) today announced $1.8 million in available funding to research new, environmentally friendly pesticides and innovative tools and strategies to replace an older treatment, methyl bromide.
Light therapy could save bees from deadly pesticides
Treating bees with light therapy can counteract the harmful effects of neonicotinoid pesticides and improve survival rates of poisoned bees, finds a new UCL study.
The effects of pesticides on soil organisms are complex
There are significant interactions between soil management factors, including pesticide application, with respect to effects on soil organisms.
Pesticides used to help bees may actually harm them
Honeybees from chlorothalanil-treated hives showed the greatest change in gut microbiome.
Research associates some pesticides with respiratory wheeze in farmers
New research from North Carolina State University connects several pesticides commonly used by farmers with both allergic and non-allergic wheeze, which can be a sensitive marker for early airway problems.
Electronic nose smells pesticides and nerve gas
Detecting pesticides and nerve gas in very low concentrations. An international team of researchers led by Ivo Stassen and Rob Ameloot from KU Leuven, Belgium, have made it possible.
Honeybees pick up 'astonishing' number of pesticides via non-crop plants
A Purdue University study shows that honeybees collect the vast majority of their pollen from plants other than crops, even in areas dominated by corn and soybeans, and that pollen is consistently contaminated with a host of agricultural and urban pesticides throughout the growing season.
Common pesticides kill amphibian parasites, study finds
A recent study by Jessica Hua, assistant professor of biological sciences at Binghamton University, and colleagues, explored the effects of six commonly used pesticides on two different populations of a widespread parasite of amphibians.

Related Pesticides Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#529 Do You Really Want to Find Out Who's Your Daddy?
At least some of you by now have probably spit into a tube and mailed it off to find out who your closest relatives are, where you might be from, and what terrible diseases might await you. But what exactly did you find out? And what did you give away? In this live panel at Awesome Con we bring in science writer Tina Saey to talk about all her DNA testing, and bioethicist Debra Mathews, to determine whether Tina should have done it at all. Related links: What FamilyTreeDNA sharing genetic data with police means for you Crime solvers embraced...