Pesticides threaten monarch butterflies

This 2014 video from the USA says about itself:

Researchers Suggest Monsanto Behind 90 Percent Drop in Monarch Butterfly Population

The monarch butterfly population has been reduced by ninety percent over the past twenty years. In terms related to the human population that’s the equivalent of losing every human in the United States except for those in Florida and Ohio.

Monsanto is now Bayer. Different name, same pesticides.

From the University of Nevada, Reno in the USA:

Milkweed, only food source for monarch caterpillars, ubiquitously contaminated

Harmful pesticides found in Western Monarch breeding ground

June 8, 2020

New evidence identifies 64 pesticide residues in milkweed, the main food for monarch butterflies in the west. Milkweed samples from all of the locations studied in California’s Central Valley were contaminated with pesticides, sometimes at levels harmful to monarchs and other insects.

The study raises alarms for remaining western monarchs, a population already at a precariously small size. Over the last few decades their overwintering numbers have plummeted to less than 1% of the population size than in the 1980s — which is a critically low level.

Monarch toxicity data is only available for four of the 64 pesticides found, and even with this limited data, 32% of the samples contained pesticide levels known to be lethal to monarchs, according to a study released today in Frontiers in Ecology and Evolution.

“We expected to find some pesticides in these plants, but we were rather surprised by the depth and extent of the contamination,” said Matt Forister, a butterfly expert, biology professor at the University of Nevada, Reno and co-author of the paper. “From roadsides, from yards, from wildlife refuges, even from plants bought at stores — doesn’t matter from where — it’s all loaded with chemicals. We have previously suggested that pesticides are involved in the decline of low elevation butterflies in California, but the ubiquity and diversity of pesticides we found in these milkweeds was a surprise.”

Milkweed was chosen as the focus of this study because it the only food source for larval monarch butterflies in the West, and thus critical for their survival.

“We collected leaf samples from milkweed plants throughout the Central Valley and sent them to be screened for pesticides,” Chris Halsch, lead author of the paper and a doctoral student in the University’s Ecology, Evolution, and Conservation Biology program, said. “This study is the first necessary step for understanding what butterflies are actually encountering. Now we can use these data to design experiments to test hypotheses about the relative importance of pesticide use and other stressors such as climate change on local butterflies.”

While this is only a first look at the possible risks these pesticides pose to western monarchs, the findings indicate the troubling reality that key breeding grounds for western monarchs are contaminated with pesticides at harmful levels.

“One might expect to see sad looking, droopy plants that are full of pesticides, but they are all big beautiful looking plants, with the pesticides hiding in plain sight,” Forister, who has been a professor int he University’s College of Science since 2008, said.

Western monarchs are celebrated throughout the western states and especially along the California coast where large congregations overwinter in groves of trees. Population declines also have been documented in the breeding grounds. Areas of inland California, including the Central Valley, offer important monarch breeding habitat throughout the spring and summer, including being the home to the very first spring generation which will continue the migration inland to eventually populate all western states and even southern British Columbia.

Declines in the population of western monarch butterflies have been linked with various stressors, including habitat loss and degradation, pesticide use, and climate change, among others. While pesticide use has been associated with declines, previous studies had not attempted to quantify the residues that butterflies can encounter on the western landscape.

The study’s findings paint a harsh picture for western monarchs, with the 64 different pesticides identified in milkweed. Out of a possible 262 chemicals screened, there was an average of nine types of individual pesticides per sample and as many as 25. Agricultural and retail samples generally had more residues than wildlife refuges and urban areas, but no area was entirely free from contamination. Certain pesticides were present across all landscapes, with five pesticides appearing more than 80% of the time. Chlorantraniliprole, the second most abundant compound, was found at lethal concentrations to Monarchs in 25% of all samples.

Understanding of pesticide toxicity to the monarch is limited, and is based on previously reported lab experiments. Thus we have much to learn about the concentrations encountered in field, but these new results raise concerns nonetheless. While this research focused on monarch toxicity, other pollinators and beneficial insects are also at risk from pesticide contamination throughout the landscape.

“We can all play a role in restoring habitat for monarchs,” said Sarah Hoyle, Pesticide Program Specialist at the Xerces Society for Invertebrate Conservation and coauthor of the paper. “But it is imperative that farmers, land managers and gardeners protect habitat from pesticides if we hope to recover populations of this iconic animal.”

Field work, gathering plant samples, was completed last spring and summer. The lab work was completed by Nicolas Baert from the Department of Entomology and manager of the Chemical Ecology Core Facility at Cornell University. Statistical computations were completed this winter by Forister and colleague James Fordyce from the Department of Ecology and Evolutionary Biology at the University of Tennessee, Knoxville.

How Bayer’s pesticides kill baby bees

This September 2015 video from the USA says about itself:

Tell Bayer: Stop Killing Our Bees

America’s bees are dying at some of the highest rates ever, struggling to survive a deluge of next-generation pesticides called “neonics” unleashed by multinational chemical giants like Monsanto, Syngenta and Bayer — the world’s largest manufacturer of these bee-killing chemicals. Why is this a problem? One out of every three bites of food we eat relies on bees for pollination. Tell Bayer‘s CEO to save our bees and stop selling highly toxic neonic pesticides in the U.S. Take action.

From Goethe University Frankfurt in Germany:

Honeybees: Pesticides disrupt nursing behavior and larval development

Unique long-term videos show the bee nursery in the hive

May 26, 2020

A newly developed video technique has allowed scientists at Goethe University Frankfurt at the Bee Research Institute of the Polytechnical Society to record the complete development of a honey bee in its hive for the first time. It also led to the discovery that certain pesticides — neonicotinoids — changed the behaviour of the nurse bees: researchers determined that they fed the larvae less often. Larval development took up to 10 hours longer. A longer development period in the hive can foster infestation by parasites such as the Varroa mite.

Honey bees have very complex breeding behaviour: a cleaning bee cleans an empty comb (brood cell) of the remains of the previous brood before the queen bee lays an egg inside it. Once the bee larva has hatched, a nurse bee feeds it for six days. Then the nurse bees caps the brood cell with wax. The larva spins a cocoon and goes through metamorphosis, changing the shape of its body and developing a head, wings and legs. Three weeks after the egg was laid, the fully-grown bee hatches from the cocoon and leaves the brood cell.

Using a new video technique, scientists at Goethe University Frankfurt have now succeeded for the first time in recording the complete development of a honey bee in a bee colony at the Bee Research Institute of the Polytechnical Society. The researchers built a beehive with a glass pane and were thus able to film a total of four bee colonies simultaneously over several weeks with a special camera set-up. They used deep red light so that the bees were not disturbed, and recorded all the movements of the bees in the brood cells.

This 26 May 2020 video says about itself:

A newly developed video technique has allowed scientists at Goethe University Frankfurt at the Bee Research Institute of the Polytechnical Society to record the complete development of a honey bee in its hive for the first time. After its hatch from the egg, the larva grows for up to six days within the cell while nursing bees continuously provide food. The cell is capped and the larva spins its cocoon prior to remaining motionless until the metamorphosis. The pupa continues to develop and the imago breaks the cell capping in order to hatch.

The article continues:

The researchers were particularly interested in the nursing behaviour of the nurse bees, to whose food (a sugar syrup) they added small amounts of pesticides known as neonicotinoids. Neonicotinoids are highly effective insecticides that are frequently used in agriculture. In natural environments, neonicotinoids arrive in bee colonies through nectar and pollen collected by the bees. It is already known that these substances disturb the navigational abilities and learning behaviour of bees. In a measure criticised by the agricultural industry, the European Union has prohibited the use of some neonicotinoids in crop cultivation.

Using machine learning algorithms developed by the scientists together with colleagues at the Centre for Cognition and Computation at Goethe University, they were able to evaluate and quantify the nursing behaviour of the nurse bees semi-automatically. The result: even small doses of the neonicotinoids Thiacloprid or Clothianidin led to the nurse bees feeding the larva during the 6-day larval development less frequently, and consequently for a shorter daily period. Some of the bees nursed in this manner required up to 10 hours longer until the cell was capped with wax.

“Neonicotinoids affect the bees’ nervous systems by blocking the receptors for the neurotransmitter acetylcholine,” explains Dr Paul Siefert, who carried out the experiments in Professor Bernd Grünewald’s workgroup at the Bee Research Institute Oberursel. Siefert: “For the first time, we were able to demonstrate that neonicotinoids also change the social behaviour of bees. This could point to the disruptions in nursing behaviour due to neonicotinoids described by other scientists.” Furthermore, parasites such as the feared Varroa mite (Varroa destructor) profit from an extended development period, since the mites lay their eggs in the brood cells shortly before they are capped: if they remain closed for a longer period, the young mites can develop and multiply without interruption.

However, according to Siefert, it still remains to be clarified whether the delay in the larval development is caused by the behavioural disturbance of the nurse bee, or whether the larvae develop more slowly because of the altered jelly. The nurse bees produce the jelly and feed it to the larvae. “From other studies in our workgroup, we know that the concentration of acetylcholine in the jelly is reduced by neonicotinoids,” says Siefert. “On the other hand, we have observed that with higher dosages, the early embryonal development in the egg is also extended — during a period in which feeding does not yet occur.” Additional studies are needed to determine which factors are working together in these instances.

In any case, the new video technique and the evaluation algorithms offer great potential for future research projects. In addition to feeding, behaviours for heating and construction were also able to be reliably identified. Siefert: “Our innovative technology makes it possible to gain fundamental scientific insights into social interactions in bee colonies, the biology of parasites, and the safety of pesticides.”

Monsanto toxic albatross around Bayer’s neck

This September 2019 German TV Video says about itself:

Turning toxic – The Bayer-Monsanto merger | DW Documentary

A year after Germany’s Bayer Group took over Monsanto, and it’s struggling to deal with the US seed giant’s controversial reputation. Now Bayer is also liable for Monsanto’s legal bills – which are starting to mount alarmingly.

Roundup, a herbicide containing glyphosate sold worldwide by Monsanto has long been suspected of causing cancer. A California court has just awarded more than $2 billion in damages to a couple who had claimed that their use of the pesticide caused them to develop non-Hodgkin’s lymphoma. Bayer’s share price halved last year, and the consequences are already making themselves felt in the company itself: Around 12,000 jobs worldwide are to be cut in the next few years, a considerable proportion of them in Germany. CEO Werner Baumann, who pushed for the merger, is coming under increasing pressure. Voicing criticism, a majority of shareholders voted against absolving Baumann and other managers of their responsibility in the merger. Bayer is in the midst of its greatest crisis.

The film traces the effects of the merger and investigates potential new health hazards emanating from glyphosate. How has Monsanto tried in the past to influence politicians, scientists and public opinion? Did the Americans actually play down or ignore the dangers? And does Bayer really distance itself from these practices?

Bayer/Monsanto spied on journalists, activists, Neil Young

This 9 August 2019 video from the USA says about itself:

Documents Reveal Monsanto [now owned by Bayer] Surveilled Journalists, Activists & Even Musician Neil Young

Explosive new documents reveal the U.S. agribusiness giant Monsanto ran a “fusion center” to surveil and discredit journalists and activists who criticized or wrote damning reports about Monsanto, as well as legendary singer-songwriter Neil Young, who released an album in 2015 called “The Monsanto Years”. Monsanto monitored Young’s Twitter activity and even analyzed the lyrics of his album.

The fusion center also surveilled journalist Carey Gillam, who has done extensive research and writing about Monsanto and its popular pesticide Roundup, which has been linked to cancer. The corporation also targeted the nonprofit research group U.S. Right to Know, which submitted Freedom of Information Act requests about the company. From Kansas City, Missouri, we speak to Carey Gillam, a veteran investigative journalist and author of “Whitewash: The Story of a Weed Killer, Cancer, and the Corruption of Science,” and from Berkeley, California, Gary Ruskin, co-founder of U.S. Right to Know.

The US American lawsuits against Monsanto these days reveal disclosure after disclosure: the corporation behind weed killer Roundup kept a blacklist of journalists, politicians and opinion makers, and even had its own intelligence service that followed, eg, Neil Young and American journalist Carey Gillam. “They do everything to attack critics. Everything.”: here.

Australian cancer victim sues Bayer-Monsanto

This 28 June 2019 Australian TV video is called Roundup linked to serious illness, claim some cancer-struck Australians | A Current Affair.

By Frank Gaglioti:

Australian cancer victim sues Bayer-Monsanto

23 July 2019

On June 4, in the first such case in Australia, the Melbourne lawn mowing service operator Michael Ogalirolo launched legal action in the Supreme Court against the global chemical giant Bayer, the current owner of Monsanto, which manufactures the herbicide Roundup.

The case follows similar recent cases in the US that have heightened concerns internationally over the use of the herbicide. Bayer, the German pharmaceutical company, bought out Monsanto, the original producer of Roundup, in 2018. The US agrichemical company had been founded in 1901.

Ogalirolo has developed the potentially lethal cancer, non-Hodgkin lymphoma (NHL), which he claims is due to 18 years of exposure to glyphosate, the active component of Roundup.

His writ declares: “The defendant [Bayer] knew or ought to have known that the use of Roundup products were dangerous for the plaintiff… in particular causing DNA and chromosomal damage in human cells, cancer, kidney disease, infertility and nerve damage among other devastating illnesses.

“As such, Roundup products are dangerous to human health and unfit to be marketed and sold in commerce, particularly without proper warnings and directions.”

Ogalirolo’s case follows three successful legal actions against Bayer in the US. School groundskeeper Dewayne Johnson sued Bayer after contracting an extremely aggressive and lethal form of NHL and was awarded $US289 million in August 2018.

In a statement to jurors, a lawyer for Johnson, Brent Wisner, condemned Monsanto for putting profits first. He said that he had seen internal Monsanto company documents “proving that Monsanto has known for decades that glyphosate and specifically Roundup could cause cancer.”

In a second case in March, the US District Court in California found that Roundup caused Edwin Hardeman to develop NHL after using Roundup for 30 years on his property. Farmers Alberta and Alva Pilliod were awarded $2 billion in May, the biggest settlement so far, after developing NHL.

Alva Pilliod told the media after her court hearing: “We wish that Monsanto had warned us ahead of time about the dangers of using Monsanto [weedkiller]… And that there was something on the front of their label that said ‘danger may cause cancer.’”

Currently, there are 13,400 claims pending in US courts and a number of other Australian cancer victims considering taking action against Bayer.

As a result of the lawsuits and significant scientific studies, action is being discussed in a number of countries. Vietnam and France banned glyphosate products in April and July respectively, and other European administrations are considering bans.

In Australia, municipal councils are reconsidering the use of Roundup.

On July 4, 500 outdoor workers from Blacktown council in suburban Sydney walked out over safety concerns over the use of Roundup. The strike took place after six workers were told that they would be placed on other duties if they refused to use the herbicide.

The workers returned to work after an Industrial Relations Commission hearing ruled that the council should trial an alternative weed control process. One crew would trial the alternative but the majority of workers would still have to use Roundup.

In June, residents reacted angrily to the Illawarra council’s annual aerial spraying of Roundup to control weeds on the local escarpment, south of Sydney. Petitions opposing the spraying were signed by thousands of residents.

One petition signed by 2,500 people stated: “Roundup is extremely dangerous as proven in court now multiple times… The health implications for residents, their pets, and small children is simply unacceptable.”

The Illawarra District Weeds Authority officer David Pomery rebuffed residents’ concerns, stating Roundup was the “only practical and feasible method to control.”

The chemical giant Monsanto introduced Roundup in 1974. According to figures published in 2016, Roundup is the most heavily applied weed killer in the history of chemical agriculture internationally. There are 500 glyphosate products available to farmers and gardeners in Australia.

The huge expansion in the use of glyphosate products occurred after 1996 when Monsanto developed genetically modified seeds, including corn, wheat, soy, canola and cotton that are immune to the effects of the herbicide. This enables farmers to spray plants throughout their lifecycle, suppressing weeds but leaving the crop unharmed. Roundup-resistant seeds are marketed as Roundup Ready. This effectively ties the farmer to the continued use of Monsanto products, including having to rebuy seed every year.

According to a scientific paper, Trends in glyphosate herbicide use in the United States and globally, published in 2016, the introduction of Roundup Ready seeds enabled a 15-fold increase in the agricultural use of Roundup and allowed Monsanto to dominate the world herbicide market.

Glyphosate is also used for pre-harvest crop desiccation: That is the application of a herbicide near the end of the growing season to cause crops to dry and die uniformly, making them easier to harvest, and increasing the risk of chemical contamination of food products.

Bayer and Monsanto have conducted relentless campaigns against critics of the herbicide and Bayer continues to aggressively promote Roundup as a safe product.

Bayer has not responded to the Australian writ, but in the US it has indicated it will challenge the court victories of the successful litigants.

“We continue to believe firmly that the science confirms that glyphosate-based herbicides do not cause cancer,” Bayer stated in March in response to the Hardeman case.

A number of scientific reports have questioned Roundup’s safety record. In 2015, the World Health Organisation’s International Agency for Research on Cancer classified the herbicide as “probably carcinogenic to humans”, based on a review of existing research.

A study published in February concluded that exposure to Roundup increased the probability of developing NHL by 41 percent. One of the co-authors, Lianne Sheppard, professor in the Environmental and Occupational Health Sciences at the University of Washington, told the Guardian that “from a population health point of view there are some real concerns.”

An Australian Broadcasting Corporation program, “The Monsanto Papers,” broadcast in October 2018, published an internal email from Monsanto’s chief toxicologist that contradicted the company’s promotion of the herbicide’s safety record. “[Y]ou cannot say that Roundup is not a carcinogen… we have not done the necessary testing on the formulation to make that statement,” the scientist stated.

Thus, there is mounting evidence that the continued promotion and sale of Roundup is another glaring example of the pursuit of corporate profit with scant concern for the potential consequences for health and the environment.

Bayer/Monsanto Roundup poison in children’s food

This 22 July 2019 video from the USA says about itself:

[Bayer/]Monsanto Monopoly Results In Our Favorite Foods Tainted With Roundup Poison

Some of your favorite foods, including the ones that you give your children every day, are full of Monsanto‘s Roundup, and yes, it is poison. Ring of Fire’s Mike Papantonio and Farron Cousins discuss this.

Bayer corporation killing American goldfinches

This 2017 video from the USA says about itself:

The 9th episode to my “Did You Know Birding?” Youtube Series

American Goldfinches are a familiar backyard bird. They one of the most welcome birds to feeders due to their peaceful way and beautiful bright color. Learn more about these lovely little finches in this episode!

From the Society of Environmental Toxicology and Chemistry in the USA:

The case of the poisoned songbirds

June 26, 2019

Researchers from the California Department of Fish and Wildlife’s Wildlife Investigations Laboratory present their results from a toxicological investigation into a mortality event involving songbirds in a new publication in Environmental Toxicology and Chemistry.

On 17 March 2017, residents in Modesto, California, reported dead birds along the street and in front yards in a section of the town. The day prior to the incident, the city had made a drench application of imidacloprid, a pesticide synthetically derived from nicotine, to the base of trees that lined the street.

Imidacloprid is a product of the Bayer corporation.

The pesticide was reportedly mixed and applied according to package directions. Researchers at the Wildlife Investigation Laboratory were notified of the incident and conducted a postmortem investigation on the dead songbirds, which were identified as American goldfinches. The cause of death was determined to be imidacloprid poisoning likely due to the ingestion of fallen elm tree seeds contaminated during the drench application.

Lead author, Krysta Rogers, and her colleagues noted that “The mortality event investigated in the present study highlights a previously unidentified risk of drench application for imidacloprid. The pesticide label states that the product be applied to the base of the tree and directly to the root zone. [However] Seeds, insects, or other invertebrates consumed by birds and other animals may be present within that zone. If these food items were contaminated during the drench application, they would be highly toxic to animals when ingested.”

The authors recommend that “drench applications not occur during seed drop to minimize the risk of exposure to animals that consume fallen seeds and that mitigation measures could be taken to prevent small animals from accessing areas treated with the pesticide, at a minimum”. Finally the authors encourage integrated pest management over the prophylactic use of pesticides as the ideal.

EPA BACKS OFF CYANIDE BOMBS TO KILL WILDLIFE The Environmental Protection Agency has suddenly backed off its reauthorization of the controversial use of “cyanide bomb” toxic traps that the Department of Agriculture employs to kill wildlife for ranchers and farmers. [HuffPost]

Bayer/Monsanto in Puerto Rico

This 18 June 2019 video says about itself:

What is Monsanto [now: Bayer] doing in Puerto Rico?

Dena Takruri gets rare access inside Monsanto‘s Puerto Rico operation, where they get huge tax breaks to test and grow GMO seeds. Meanwhile, thousands of plaintiffs across the U.S. are suing the corporation, claiming that its weedkiller Roundup has caused cancer. In Puerto Rico, locals are blaming Monsanto for getting them sick.

Bayer loses Roundup cancer court case again

This 17 May 2019 video from the USA says about itself:

Bayer Must Pay $2 Billion To Couple In Roundup Cancer Trial

May 13 (Reuters) – A California jury on Monday awarded more than $2 billion to a couple who claimed Bayer AG’s glyphosate-based Roundup weed killer caused their cancer, in the largest U.S. jury verdict to date against the company in litigation over the chemical. It was the third consecutive U.S. jury verdict against the company in litigation over the chemical, which Bayer acquired as part of its $63 billion purchase of Monsanto last year. Both other jury verdicts also came in California, one in state court and one in federal court. The jury in San Francisco Superior Court in Oakland on Monday said the company was liable for plaintiffs Alva and Alberta Pilliod’s contracting non-Hodgkin’s lymphoma, a spokeswoman for the couple said.

Translated from Dutch NOS TV today:

Jury wants billion-dollar compensation for cancer caused by Roundup

The German chemical company Bayer has to pay much compensation for the third time because of the Roundup pesticide. A jury in the United States state of California believes it has been proven that a couple has gotten a rare form of lymph node cancer through the chemical.

If it is up to the jury, then Bayer must pay 2 billion dollars (1.8 billion euros) in damages. Due to federal laws, the final compensation will be much lower. In the two previous cases, the amount was around $ 80 million.


Bayer will appeal the ruling. The corporation maintains that glyphosate is not carcinogenic and says all studies confirm that.

Bayer ‘forgets’ to say: ‘all studies paid by us‘.

The product is sold in more than 160 countries. The three lawsuits that have now been conducted are the first ones of probably thousands that will be conducted about the pesticide.

Roundup was made by the Monsanto corporation. That was purchased by Bayer last year. Since the scandal, Bayer‘s shares have declined steadily. After today’s ruling, the share fell again on the stock exchange. Nevertheless, the chief executive recently said that purchasing Monsanto “was the right decision”.

Bayer’s pesticides help mites to kill honeybees

This 14 March 2019 video says about itself:

France: Activists swarm Bayer HQ in Paris to protest bee deaths

Activists dressed as bees vandalised Bayer’s Paris headquarters on Thursday, during a protest against the corporation’s environmental impact and use of pesticides.

The protesters used fire extinguishers to spray yellow paint on the windows at the entrance of the building, and then poured a sticky liquid outside the front door, in what Association for the Taxation of Financial Transactions and for Citizens’ Action (ATTAC) spokesperson Annick Coupe called a symbolic gesture.

“You see bees, symbolically, came to tell Bayer that it’s killing them. And so they poured honey, always symbolically, and also poured a sticky product on the ground and brought it back to Bayer,” she said.

The international pharmaceutical corporation came under fire in 2016 after a study they conducted jointly with agricultural company Syngenta revealed their pesticide products caused severe harm to honeybees. The results of the survey were first left unpublished, until environmental group Greenpeace gained access to the study through freedom of information laws.

Coupe said the aim of the protest was “to show that it is possible to act against the multinational companies who contribute to harming our planet with impunity.”

When scientists blamed neonicotinoid pesticides produced by corporations like Bayer/Monsanto for massive dying of bees, sometimes the reaction was: Neonics do not kill bees. Varroa mites do.

However, in 2015 there already was this study: Interaction between Varroa destructor and [Bayer‘s] imidacloprid [pesticide] reduces flight capacity of honeybees.

Now, a new study …

From the University of Guelph in Canada:

Neonics hinder bees’ ability to fend off deadly mites

April 22, 2019

A University of Guelph study is the first to uncover the impact of neonicotinoid pesticides on honey bees‘ ability to groom and rid themselves of deadly mites.

The research comes as Health Canada places new limits on the use of three key neonicotinoids while it decides whether to impose a full phase-out of the chemicals.

Published in the Nature journal Scientific Reports, the study revealed that when honey bees are infected with varroa mites and then regularly exposed to low doses of a commonly used neonicotinoid called clothianidin, their self-grooming behaviour drops off.

Without that self-grooming, bees are susceptible to mites that can also carry viruses that can quickly kill, said lead author Nuria Morfin Ramirez, who completed the research along with Prof. Ernesto Guzman, School of Environmental Sciences, as part of her PhD.

“When bee colonies began to collapse years ago, it became clear there wasn’t just one factor involved, so we were interested in whether there was an interaction between two of the main stressors that affect bees: varroa mites and a neurotoxic insecticide, clothianidin,” said Morfin.

“This is the first study to evaluate the impact on the grooming behaviour of bees.”

Neonicotinoids, or “neonics,” are the most commonly used insecticides in Canada. They are coated on canola and corn seeds or sprayed on fruit and vegetable plants and trees. But they have also been linked to honey bee colony collapses.

Varroa mites are also contributing to colony collapses and have been associated with more than 85 per cent of colony losses.

The mites kill bees by slowly feeding off their body fat and hemolymph (blood), and can also transmit a virus called deformed wing virus (DWV). One of the only ways bees can protect themselves is to groom aggressively and brush the mites off.

The researchers wanted to know whether the two stressors of pesticide exposure varroa mites were working together to contribute to bee deaths. The research team used bees from U of G’s Honey Bee Research Centre and exposed them to a widely used neonic clothianidin, either on its own or along with varroa mites.

They experimented with three doses of clothianidin, all similar to what the bees would experience while feeding on flower nectar of neonic-treated crop fields, but all low enough to be considered sublethal.

“What we found was a complicated interaction between the mite and the pesticide that decreased the proportion of bees that groomed intensively, and affected genes associated with neurodegenerative processes,” Morfin said.

Bees exposed to medium level doses of the neonic showed no changes in grooming behaviour, but when they were also introduced to varroa mites, the proportion of bees that groomed intensively was 1.4 times lower compared to the bees exposed to clothianidin alone.

When exposed to the lowest dose of the pesticide, the proportion of bees that groomed significantly dropped. The lowest dose was also linked to an increased level of deformed wing virus — an effect not seen at the higher doses.

“These results showed a complex and non-additive interaction between these two stressors,” said Guzman. “This study highlights the importance of reducing stressors that bees are exposed to, to reduce the risk of disease and consequently colony mortality.”

Today, scientists of the Institute of Bee Health of the University of Bern and the honeybee research association COLOSS have published an article in the peer-reviewed journal Scientific Reports that shows a synergistic time-lag interaction between the parasitic mite Varroa destructor and neonicotinoid insecticides reducing survival of winter honeybees, Apis mellifera. This article emphasizes the need to develop sustainable agricultural and apicultural schemes: here.

Many pesticides that have been banned or are being phased out in the EU, Brazil and China, are still widely used in the USA, according to a new study: here.

Prenatal exposure to the organophosphate pesticides has been linked to poorer cognition and behavior problems in children. A new study is one of the first to use advanced brain imaging to reveal how exposure can actually change brain activity. Teenagers estimated to have higher levels of prenatal exposure to organophosphates showed altered brain activity compared to their peers while performing tasks that require executive control, the study found: here.