(Beyond Pesticides, September 17, 2019) The poisonous farm fields migratory birds forage on during their journey reduce their weight, delay their travel, and ultimately jeopardize their survival, according to new research published in the journal Science.  Like their effects on pollinator populations, neonicotinoid insecticides generally are not killing migratory songbirds outright, but instead precipitating a cascade of sublethal impacts that reduces their fitness in the wild. As the authors told Environmental Health News, the study is a call not simply to ban neonics or one class of chemical, but to change the entire farming system toward more sustainable bird and bee-friendly practices. Using new technology, this study was not only able to dose wild-caught songbirds (white-crowned sparrows), but also track their migration route using automated telemetry. Apart from the control group that received no pesticide exposure, sparrows were treated at levels well below the median lethal dose (3% of the lethal dose in the ‘low’ exposure group and 10% within the ‘high’ exposure group), and permitted to continue on their migratory path. These are exposure amounts similar to a songbird accidentally ingesting a few treated seeds, according to the study. Within six hours, both the ‘low’ and ‘high’ exposure group […]

(Beyond Pesticides, July 17, 2019) A March 2017 bird kill incident in Modesto, CA can be traced directly back to an insecticide “soil drench” applied to the base of several elm trees by pesticide applicators hired by the city, as detailed in a study published last month in the Journal of Environmental Toxicology and Chemistry. The chemical in question, the neonicotinoid imidacloprid, is implicated in the ongoing pollinator crisis and insect apocalypse, but can also affect bird populations. Prior research estimated that a single seed coated with the insecticide is enough to kill a songbird; this study confirms that such a scenario can and does play out in the real world. Progress and improvement will only occur when pest management practices stop focusing on pesticide use to solve routine pest problems and emphasize prevention. As part of city-wide pest management activities, Modesto officials said that imidacloprid was applied to elm trees in several front yards in a local neighborhood. The application took the form of a “soil drench,” which is when pesticide products are applied to the soil around the base of a tree or shrub. The systemic property of imidacloprid and other systemic insecticides means that the chemical will […]

(Beyond Pesticides, June 8, 2019) Scientists studying the precipitous decline in populations of monarch butterflies are searching for causes, and pesticide use is one of the factors under their (figurative) microscopes. Purdue University entomology professor Ian Kaplan, PhD and doctoral student Paola Olaya-Arenas recently turned their attention to a poorly studied potential factor — exposure during monarchs’ larval stage to non-target pesticides on their primary host plant and food source, common milkweed (Asclepias syriaca). In Frontiers in Ecology and Evolution, the researchers report finding evidence of 14 different agricultural pesticides on milkweed near Indiana farm fields, including neonicotinoids clothianidin and thiamethoxam, the pyrethroid deltamethrin, and imidacloprid in a few samples. The research team’s primary aim was to identify and measure the range of pesticides to which monarch caterpillars might be exposed, or which they might consume, on milkweed plants in agricultural landscapes. Secondarily, they hoped to learn how pesticide presence varies with distance between milkweed plants and nearby agricultural sites. In the subject Indiana environs, where corn and soybeans are dominant crops, the study found neonicotinoid residues on milkweed, particularly those of the active ingredients in clothianidin and thiamethoxam. They note, “Although seed treatment data are no longer reported for U.S. […]

(Beyond Pesticides, May 6, 2019) Beleaguered pollinators deal with a multitude of human-engineered threats: habitat fragmentation and loss via development and agricultural intensification, ecosystems and food sources tainted with toxic synthetic pesticides, and shrinking food sources via habitat and biodiversity loss. Research out of the Imperial College of London shows that such challenges are exacerbated, for bumblebees, by another impact of pesticide exposure — impaired flight endurance and dynamics. Published in the journal Ecology and Evolution in late April, ”Pesticide exposure affects flight dynamics and reduced flight endurance in bumblebees” examines how acute exposure to the neonicotinoid imidacloprid affects the nature of bumblebee foraging flight. The study’s researchers find that worker bumblebees so exposed exhibit significant diminishment of flight endurance — measured as both distance and duration — to approximately one-third of what control workers demonstrate. This new information, aggregated with the many other factors that threaten pollinators, points to the importance of ending the use of chemical controls, such as the neonicotinoid imidacloprid, and transitioning to organic systems of agricultural pest management that do not rely on toxic compounds that harm wildlife, ecosystems, water resources, and humans. Previous research has shown numerous impacts of pesticide exposure on bumblebees, and of neonicotinoid exposure, in […]

(Beyond Pesticides, May 2, 2019) Researchers have documented an increase in food and drinking water residues of neonicotinoids, insecticides linked to breast cancer. Using the Pesticide Data Program (PDP), 1999-2015, of the U.S. Department of Agriculture, the researchers identified near-peak detection frequencies in 2015, after a decline from 2008-2013. Imidacloprid remains the most common neonicotinoid detected across imported commodities, while the neonicotinoids clothianidin, thiamethoxam, acetamiprid, and flonicamid are replacing imidacloprid in domestic production. Authors note that these newer neonicotinoids are potentially more toxic than imidacloprid, raising concerns for understudied human health and environmental impacts. The study, Trends in neonicotinoid pesticide residues in food and water in the United States, 1999–2015, published in the journal Environmental Health, finds the highest detection frequencies for neonicotinoids in drinking water, with 30% of treated drinking water turning out positive for imidacloprid in 2011. Certain fruits and vegetables are also frequently contaminated by neonicotinoids, with detection frequencies ranging from 20% to as high as 57% in the case of imidacloprid on cauliflower. While the study points to specific fruits and vegetables as posing higher risk, the main message reaches beyond individual commodity or individual neonicotinoid results. Authors uncover a systematic increase in detection of neonicotinoid […]

(Beyond Pesticides, March 22, 2019) A two-year study, published March 14,  finds that field-relevant contamination with the neonicotinoid insecticide imidacloprid causes reduced body weight and metabolism in white-tailed deer, and – in fawns – mortality. Remarkably, researchers uncovered imidacloprid levels in free-ranging deer a full 3.5 times higher, on average, than the levels in the animals treated in their experiment. These new findings add to the mounting evidence of the hazards posed by current patterns of neonicotinoid use, while evidence of benefits remains sparse. The study, published in Nature Scientific Reports, includes two years of data on the physiological and behavioral outcomes of imidacloprid contamination in 80 white-tailed deer housed in a South Dakota State University captive research facility. Notably, researchers were unable to entirely control imidacloprid levels in untreated deer, most likely due to background contamination from corn- and soy-based feed, and surrounding vegetation infiltrated by runoff from nearby agricultural fields. This background contamination altered, but did not compromise, the analysis. Researchers found that imidacloprid levels detected in the spleens of treated and control animals were significantly predictive of reduced thyroid hormone levels, shorter jawbones, lower activity levels, and higher fawn mortality. Lead authors Elise Berheim, Jonathan Jenks, PhD, […]

(Beyond Pesticides, March 13, 2019) A study on the impact of two neonicotinoid pesticides shows differential gene expression in bumblebees (Bombus terrestris) after exposure. Considering the current worldwide plight of insects, the authors of point to the cutting edge research as both a reason and a methodology to more carefully examine the effects of pesticides. “Caste- and pesticide-specific effects of neonicotinoid pesticide exposure on gene expression in bumblebees” was published in the journal Molecular Ecology in early March. Researchers fed variable colonies with clothianidin or imidacloprid-laced sucrose. They analyzed gene expression in the heads of worker bumblebees and colony queens using RNA sequencing (RNA-seq), inspired by biomedical techniques. This approach allowed for new insight on what genes and pathways are affected by neonicotinoid exposure. Study author Yannick Wurm, PhD, stated in a press release, “Our work demonstrates that the type of high-resolution molecular approach that has changed the way human diseases are researched and diagnosed, can also be applied to beneficial pollinators. This approach provides an unprecedented view of how bees are being affected by pesticides and works at large scale. It can fundamentally improve how we evaluate the toxicity of chemicals we put into nature.” Clothianidin had a stronger […]

(Beyond Pesticides, March 7, 2019) A publication in the journal Environmental Health Perspectives highlights findings from a recent study showing that environmental concentrations of the neonicotinoid insecticides thiacloprid and imidacloprid increase expression of a gene linked to hormone-dependent breast cancer. Authors of the featured study uncovered a pathway through which neonicotinoids stimulate excess estrogen production, known to occur during the development of progressive hormone-dependent breast cancer. In the words of the authors, “Our findings highlight the need for further research to assess the potential impacts of low-dose and chronic exposure to neonicotinoids on endocrine processes affecting women’s health.” The study, published in Environmental Health Perspectives in April 2018 by researchers at the University of Quebec, is not the first to point to a potential link between neonicotinoid exposure and breast cancer. A 2015 study by the same research group revealed that the neonicotinoids thiacloprid and thiamethoxam, along with the herbicide atrazine, induce similar effects in breast cancer cells. In both studies, exposure to neonicotinoids alter promoter activity to induce heightened production of the enzyme aromatase, which is known to stimulate estrogen production and thereby cancer cell proliferation. The recently published study, authored by Silke Schmidt, PhD, brings greater urgency to […]

(Beyond Pesticides, November 28, 2018) Recent research out of Harvard University and published in the journal Science has demonstrated some of the mechanisms through which exposures to neonicotinoid pesticides harm bumblebee populations. The study found that exposure to imidacloprid, a neonicotinoid — the most widely used category of pesticides worldwide — directly impacts social behaviors in bumblebees. These behaviors have serious effects on the functioning and viability of bee colonies. In the research experiment, worker bees exposed to imidacloprid exhibited reduced general and nurturant activity, and a tendency to locate themselves at the periphery of the nest. The study noted decreased caretaking and nursing behaviors, which in turn harms productivity and thermal regulation in the colony. These tasks are important to colony development; impaired thermoregulation negatively affected the bees’ typical construction of an insulating wax canopy for the nest, and poor caretaking can affect brood growth. Investigators noted that, “Neonicotinoids induce widespread disruption of within-nest worker behavior that may conribute to impaired growth. . . . These changes in behavior acted together to decrease colony viability, even when exposure was nonlethal.” The authors also observed that many of these dysregulated behaviors were more pronounced at night than during sunlight hours, and […]

(Beyond Pesticides, July 12, 2018) Neonicotinoid insecticides have become notorious for their impacts to insect pollinators like bees and butterflies, but research finding the presence of these chemicals in wild turkeys is raising new concerns about the ubiquitous nature of these chemicals once released into the environment. Published in Environmental Science and Pollution Research by a team from the University of Guelph (UG), this new study highlights the broader effects of neonicotinoids on wildlife, and underlines calls to restrict the use of these products in favor of a more sustainable pest management approach. Looking at roughly 40 wild turkeys in southern Ontario, researchers found 10 that contained pesticide residue in their livers. Claire Jardine, PhD, pathobiology professor and study co-author notes that wild turkeys in agricultural regions are more likely to be contaminated. “Wild turkeys supplement their diet with seeds from farm fields,” she indicated in a press release. The agrichemical industry coats a majority of corn and soybean seeds with neonicotinoids prior to planting. Because of their systemic nature, neonicotinoids are incorporated the seedlings as they grow, with the promise by the industry that this will alleviate pest pressure. However, a significant body of research, including EPA studies, have […]

(Beyond Pesticides, June 6, 2018) By the close of 2018, three top neonicotinoid (neonic) pesticides, linked to the worldwide decline in bee populations, will be banned for outdoor use in the European Union (EU), based on the General Court of the European Union’s (GCEU) ruling last month. The GCEU, the equivalent of the U.S. Supreme Court, ruled in favor of taking precautionary action to protect pollinators from clothianidin, imidacloprid, and thiamethoxam. This ruling allows for the limited use of neonic-treated seeds grown in permanent greenhouses where contact with bees is not expected. In its lawsuit, multinational seed and chemical companies, Syngenta and Bayer –manufacturers of the neonics in question– argued unsuccessfully that the pesticides do not necessarily harm bees if farmers use them according to label instructions. Syngenta also sought compensation of approximately $435 million to offset market losses resulting from the ban, but that, too, was denied. In rejecting the arguments of Syngenta and Bayer, the high court aligned itself with the European Food Safety Authority (EFSA) and its assessment of the harm caused by the widely used pesticides. EFSA’s updated assessment, released in February of this year, provided convincing evidence that neonics represent a risk to wild bees and […]

(Beyond Pesticides, May 6, 2018) The Washington State Department of Ecology (Ecology) temporarily denied a permit to spray Willapa Bay and Grays Harbor with the toxic neonicotinoid insecticide imidacloprid. Your comments helped achieve the temporary decision and comments are now needed again to make the denial permanent. The public comment period closes on May 14, 2018. Willapa Bay and Grays Harbor, with a number of unique ecosystems, and among the most pristine estuaries in the U.S., have been targeted with a plan to spray the toxic neonicotinoid insecticide imidacloprid to kill the native burrowing shrimp in beds of commercial Japanese oysters. This insecticide use will have deadly effects on keystone aquatic organisms. Based on a Supplemental Environmental Impact Statement (SEIS) and public input, Ecology temporarily denied the permit. Tell Ecology to restore the bays instead of spraying them! Ecology bases its decision on these factors: Too great an impact on the marine organisms that live in the sediments where the pesticide application is proposed. Too much uncertainty about the long-term impacts associated with this pesticide. Negative impacts on fish and birds caused by killing sources of food and disrupting the food web. Even at low concentrations, imidacloprid has significant impacts […]

(Beyond Pesticides, April 11, 2018) The request by shellfish growers in Washington State to apply the neonicotinoid insecticide, imidacloprid, on oyster and clams beds to control native burrowing shrimp was denied by the Department of Ecology (Ecology) after it determined “environmental harm from this neonicotinoid pesticide would be too great.” Concerned resident and environmental advocates have been opposed to the proposed use citing harms to aquatic life including fish habitat, and long-term ecological damage. Shellfish growers from Willapa-Grays Harbor Oyster Growers Association requested a permit from the state to use the imidacloprid on burrowing shrimp that the growers said impede traditional shellfish cultivation. They sought a state National Pollution Discharge Elimination System (NPDES) permit to apply imidacloprid to 500 acres of shellfish beds within Willapa Bay and Grays Harbor, over a period of five years. The growers first applied for a permit in 2015 to treat 2,000 acres of tidelands, but after a strong public outcry, they withdrew the request. In 2016, they applied for a new permit to treat less acreage and Ecology published a draft Supplemental Environmental Impact Statement (SEIS) in 2017 on the potential impacts imidacloprid application would have to the bay. Now, Ecology, after thoroughly evaluating […]

(Beyond Pesticides, March 15, 2018) On Tuesday, a group of 56 scientists studying the effects of neonicotinoids sent a letter to California’s Department of Pesticide Regulation (CDPR) highlighting the threat neonicotinoids pose to the health of California’s waterways. The scientists urge CDPR to take steps to reduce neonicotinoid contamination of the state’s streams and rivers. This comes as neonicotinoids were recently reported to be pervasive throughout the Great Lakes, and federal assessments confirm high risks to aquatic species. According to the letter, neonicotinoids are already found in California waterways at levels that exceed the freshwater invertebrate aquatic life benchmarks and could harm or kill many sensitive aquatic invertebrate species. Citing a 2016 study by the Xerces Society that found imidacloprid frequently in California’s rivers and streams at levels harmful to species such as mayflies and caddisflies. Imidacloprid samples in California from 2010-2015 showed that 42% (197 of 468) of detections exceeded the acute invertebrate benchmark and all of the detections exceeded the chronic invertebrate benchmark. In certain regions of the state, particularly agricultural areas, the imidacloprid benchmark for acute effects was more frequently exceeded. The scientists note these chemicals can “have consequences for broader ecosystems. Declines in aquatic invertebrates put other species […]

(Beyond Pesticides, March 12, 2018) European Regulators Confirm Neonicotinoids Harm Bees, Increasing Likelihood of Continent-Wide Ban A comprehensive assessment released last week by the European Food Safety Authority (EFSA) confirmed that neonicotinoids, the most widely used class of insecticides in the world, pose risks to honey bees and wild pollinators. EFSA analyzed over 1,500 studies from academia, beekeeper associations, chemical companies, farmer groups, non-governmental organizations, and national regulators. EFSA’s risk assessment provides a definitive, independent conclusion that overall, continued use of these chemicals risks the long-term health of pollinator populations. Tell Your Governor to Ban Neonicotinoid Insecticides “The availability of such a substantial amount of data as well as the guidance has enabled us to produce very detailed conclusions,” said Jose Tarazona, PhD, head of EFSA’s Pesticides Unit in a press release. This is EFSA’s second comprehensive evaluation of the three most commonly used neonicotinoids: imidacloprid, clothianidin, and thiamethoxam. Earlier research finalized in 2013 led the European Union (EU) to ban use of the three neonicotinoids on agricultural flowering crops. The new assessment applies EFSA guidance to assessing risks to bees and on the initial review. It includes literature not only on honey bees, but also on wild pollinators, including bumblebees […]

(Beyond Pesticides, February 16, 2018) U.S. Representatives Blumenauer (D-OR) and Jim McGovern (D-MA) this week announced plans to reintroduce the Saving America’s Pollinators Act, (previously H.R. 3040) which suspends the registration of certain neonicotinoid insecticides until the U.S. Environmental Protection Agency conducts a full scientific review that ensures these chemicals do not harm pollinators. Beyond Pesticides joined Rep. Blumenauer and other experts from environmental, conservation, whistleblower and farmworker health groups on Capitol Hill to urge Congress to take action to protect pollinators in the face of ongoing obstruction by an increasingly industry-influenced EPA. “Pollinators are the backbone of America’s agriculture system. Acting now to protect them and stop their decline is essential to the sustainability of our nation’s food supply,” Rep. McGovern said. “Simply taking the word of the manufacturers that their products are safe is not an option. Consumers need strong oversight. That is why I am proud to join Congressman Blumenauer in demanding the EPA fully investigate the effect that certain harmful pesticides may have on the vitality of our pollinators.” Numerous scientific studies implicate neonicotinoid pesticides as key contributors to the global decline of pollinator populations. EPA’s own scientists have found that neonicotinoids pose far-reaching risks to […]

(Beyond Pesticides, October 11, 2017) Last week, the Natural Resources Defense Council (NRDC) filed a lawsuit challenging the U.S. Environmental Protection Agency’s (EPA) registration of neonicotinoid pesticides – acetamiprid, dinotefuran, and imidacloprid, and the agency’s failure to first consult with the U.S. Fish and Wildlife Service on the pesticides’ impact on threatened or endangered species. The lawsuit, filed in the U.S. District Court for the District of Columbia, challenges the failure of the federal government to evaluate the impacts of neonicotinoid pesticides (“neonics”) on threatened and endangered species, like the rusty patched bumble bee, the black-capped vireo, and the San Bruno elfin butterfly. The suit cites widespread presence of neonics in the environment which presents serious risks to wildlife across large portions of the country. It contends that they pose significant adverse consequences to threatened and endangered species. According to the lawsuit, because of toxicity and pervasive environmental contamination, NRDC is now challenging EPA’s registrations of pesticide products containing one of three main neonic active ingredients—acetamiprid, dinotefuran, and imidacloprid—and seeks vacatur of those registrations until EPA complies with the law. “The EPA ignored endangered bees, butterflies, and birds when it approved the widespread use of neonics,” said Rebecca Riley, a senior […]

(Beyond Pesticides, July 6, 2017) The Washington State Department of Ecology (Ecology) is evaluating a new permit application for the use of imidacloprid, a toxic neonicotinoid, to combat a growing native population of burrowing shrimp that threatens oyster beds in Willapa Bay and Grays Harbor in Washington state. The application was recently submitted to Ecology by a group of oyster farmers from the Willapa Grays Harbor Oyster Growers Association (WGHOGA), who “propose to use the pesticide to treat tide lands to support their aquaculture practices.” Imidacloprid is known to be toxic to bees and aquatic organisms, raising questions on the impacts of its use on the long-term ecological health of the bays. In April 2015, much to the dismay of activists and concerned local residents, Ecology approved a permit submitted by oyster farmers for the use of imidacloprid to combat burrowing shrimp in these aquatic ecosystems. But with a nationwide public outcry, the permit was withdrawn in May 2015. The recent request that was submitted differs in several ways from this 2015 permit, including: The new permit proposes treating 485 acres in Willapa Bay and 15 acres in Grays Harbor, compared to 2,000 acres combined from both water bodies in the 2015 permit. The oyster farmers […]

(Beyond Pesticides, April 5, 2017) A new study, Occurrence of Neonicotinoid Insecticides in Finished Drinking Water and Fate during Drinking Water Treatment, has detected neonicotinoids, a class of insecticides known for their detrimental effects on bees, in treated drinking water. This marks the first time that these insecticides have been found in water sourced straight from the tap. Federal regulators have not yet addressed safe levels of neonicotinoids in drinking water, so at this point, any detection of these chemicals is cause for concern. The study authors “report for the first time the presence of three neonicotinoids in finished drinking water and demonstrate their general persistence during conventional water treatment.” Drinking water samples “collected along the University of Iowa treatment train” over a seven week period, May through July, 2016 directly after corn and soy planting, find three neonicotinoids, clothianidin, imidacloprid, and thiamethoxam at levels ranging from 0.24 to 57.3 ng/L (nanogams per liter). The University of Iowa tap water is run through a water treatment plant that uses conventional treatment methods.  In contrast, the Iowa City water treatment methods (granular activated carbon filtration) result in substantially lower levels of the neonicotinoids. Additionally, the researchers found that extensive transformation of clothianidin […]

(Beyond Pesticides, March 6, 2017) A study published last month by Canadian researchers finds that exposure to the neonicotinoid insecticide imidacloprid at environmentally relevant levels results in slight delays in metamorphosis in the tadpoles of the wood frog. While the authors find that this slight delay is not necessarily a cause for concern from an ecological perspective, sublethal effects of pesticide mixtures and a variety of stressors in the environment play a role in extending juvenile periods in frogs, which can increase mortality and population decline. Because neonicotinoids are so widely use, the authors recommend further research on their impact on declining frog populations. The study, published in Environmental Toxicology and entitled, “Sublethal effects on wood frogs chronically exposed to environmentally relevant concentrations of two neonicotinoid insecticides,” looks at the chronic exposure effects of the neonicotinoids imidacloprid and thiamethoxam on the wood frog (Lithobates sylvaticus). The wood frog was chosen because it is native to North America and has a wide distribution across the continent. The researchers exposed tadpoles to environmentally relevant concentrations (1ug/L, 10ug/L and 100ug/L) of the commercial formulation of the neonicotinoids (Admire and Actara). The study finds a significant difference in time for tadpoles to metamorphose. Tadpoles exposed […]

(Beyond Pesticides, January 13, 2016) Just prior to the U.S. Environmental Protection Agency (EPA) announcement on January 12 that several neonicotinoid insecticides “do not pose significant risks to bee colonies,” the preprint version of a new review of neonics identified the range of lethal and sublethal effects of the chemicals on non-target organisms.  The review, The Environmental Risks of Neonicotinoid Pesticides: a review of the evidence post-2013, authored by Dave Goulson, PhD, and Thomas James Wood, a PhD candidate, concludes that studies published since the 2013 European Food Safety (EFSA) published risk assessments show even greater risks. The EFSA assessment, which led to a moratorium on neonicotinoid uses, found that certain neonics on specific flowering crops pose a high risk to bees. With reference to the 2013 EFSA risk assessment conclusions as their baseline, the researchers summarize the difference in risk for certain categories, including: “Risk of exposure from and uptake of neonicotinoids in non-crop plants. Uptake of neonicotinoids by non-target plants was considered likely to be negligible, though a data gap was identified. Many studies have since been published demonstrating extensive uptake of neonicotinoids and their presence in the pollen, nectar and foliage of wild plants. Exposure from non-target plants clearly represents a Greater […]

(Beyond Pesticides, January 12, 2017) Yesterday marked a monumental event in the fight against pollinator declines, as the rusty patched bumblebee became the first bee species to officially be declared endangered by the U.S. Fish and Wildlife Service (FWS). According to FWS, endangered species designations are made when a species is “in danger of becoming extinct throughout all or a portion of their range.” Tom Melius, Service Midwest Regional Director for FWS, stated in a press release that, when it comes to this determination, “[FWS’s] top priority is to act quickly to prevent extinction of the rusty patched bumble bee. Listing the bee as endangered will help [the agency] mobilize partners and focus resources on finding ways right now to stop the decline.” Listed yesterday in the Federal Register, the ruling will go into effect February 10, 2017. This is a victory for environmental groups who have fought to protect the rusty patched bumble bee from widespread threats, such as habitat loss and pesticide use. According to FWS, the rusty patched bumble bee was once widespread across the United States and parts of Canada, but declined dramatically in the 1990s.  Since then, their populations have dwindled and their overall decline is estimated at 91 […]

(Beyond Pesticides, January 10, 2017) Exposure to neonicotinoid (neonic) insecticides leads to a decrease in pollination frequency and fewer social interactions in bumblebees, according to research published by scientists from Harvard University and University of California, Davis. The study, released last year but presented this week at the Society for Integrative and Comparative Biology’s annual meeting, underscores the need for regulators and policy makers to eliminate use of these chemicals, not only to protect honey bees, but also wild pollinators like the bumblebee. While worker bumblebees (Bombus impatiens) divide their tasks within the colony in a similar manner to honey bees, their nests appear quite different than their more structured cousins. “Bumblebee nests are not the organized, beautiful geometry of the honeybee,” said James Crall, PhD candidate in Harvard’s Department of Organismic and Evolutionary Biology. Instead, “They’re more a hodge-podge of food and larvae in a pile in the middle of the nest space.” For their study, researchers placed four bumblebee colonies in a mesh enclosed area, tagged each bee, and observed them foraging on tomato flowers grown in a pollinator-excluding greenhouse (to ensure bees had freshly-opened flowers for pollination each day). After observing normal behavior, bees within each colony […]