Herbicides, Not Insecticides, Biggest Threat to Bees

AGFAX   By Bonnie Coblentz    December 17, 2015 

People who care about honeybees know that insecticides and pollinators are usually a bad mix, but it turns out that herbicides used to control weeds can spell even bigger trouble for bees.

Jeff Harris, bee specialist with the MSU Extension Service and Mississippi Agricultural and Forestry Experiment Station researcher, said herbicides destroy bee food sources.

“When farmers burn down weeds before spring planting, or people spray for goldenrod, asters and spring flowers, or when power companies spray their rights-of-way, they’re killing a lot of potential food sources for bees and wild pollinators,” he said.

Harris said the direct effect of these chemicals on bees is so much less of an issue than their loss of food supply.

“Disappearing food is on the mind of beekeepers in the state,” he said. “That is even more important to them than losses of bees to insecticides.”

Johnny Thompson, vice president of the Mississippi Beekeeping Association, is a cattle and poultry farmer in Neshoba County who has been in the bee business for the last 10 years.

“Before we got back into bees, I sprayed pastures by the barrel to kill weeds. As a cattle farmer, weeds are a nuisance,” Thompson said. “I’m trying to grow grass for the cows to eat and not weeds, but as a beekeeper, those weeds are not weeds. That’s forage for the bees.”

Today, Thompson said he uses the bush hog more than he sprays herbicides to keep the food supply for bees intact on his land.

“If you kill everything the bee has for food, you may as well go in and spray the hive directly. The bees are going to die,” he said. “All the emphasis is being put on insecticide, but the greater risk to bees are the herbicides.”

He has made management changes for the sake of his bees’ food supply, but he recognizes the tension between current agricultural management practices and pollinators’ best interests.

“When you travel through the Delta or the prairie part of the state in February, the row crop land is purple with henbit blooming. By the end of March, it’s all gone because farmers burned it down with chemicals to try to kill everything in the field before they plant,” he said.

“They burn it down early because weeds in March or early April are a reservoir for insect pests to the crops that will soon be planted,” Thompson said.

Crops in the field, especially soybeans, are great sources of bee forage, and farmers and beekeepers can coordinate to protect both of their interests. 

“We moved bees to the Delta this summer to make soybean honey,” Thompson said. “We’re working with the growers to try to put the bees in areas that are fairly protected and won’t get directly sprayed.”

But farmland is not the only place bees find food. Yards, roadsides, golf courses and power line rights-of-way are other places bees forage when plants are allowed to bloom naturally.

“We need to stop looking at them as weeds and instead look at these plants as forage,” Thompson said. “I can manage around the insecticides, but if herbicide use means there’s nothing for a bee to eat, there’s no reason to put a hive in an area.”

http://agfax.com/2015/12/17/pollinators-herbicides-not-insecticides-biggest-threat-to-bees/

Insecticide Could Be Culprit in Honey Bee Die Offs

New York Post     Reuters   August 18, 2015

A type of insecticide under scrutiny by the White House because of fears about its impact on honeybees has been found in more than half of streams sampled across the United States, according to a study by government researchers published Tuesday.

The study, published in Environmental Chemistry and conducted by US Geological Survey researchers, found that five types of insecticides that are known as neonicotinoids were present in varying degrees in 149 samples taken from 48 streams.

At least one type was detected in 63 percent of the samples collected, USGS researcher Michael Focazio said. The samples included many waterways through the Midwest and Southeast. Concentration levels varied.

Over the last few years, evidence has mounted that links the use of neonics, as they are known, to widespread die-offs of honeybees needed to pollinate crops. There are also fears the insecticides are harming other pollinators.

Neonicotinoids, chemically similar to nicotine, are one of the fastest-growing classes of insecticides worldwide and are used both in agricultural and urban settings. They are popular with farmers and are often used to coat seeds before they are planted.

The study represents the first national-scale investigation of the environmental occurrence of neonicotinoid insecticides in agricultural and urban settings, the USGS said. The research spanned 24 states as well as Puerto Rico.

“In the study, neonicotinoids occurred throughout the year in urban streams while pulses of neonicotinoids were typical in agricultural streams during crop planting season,” USGS research chemist Michelle Hladik, the report’s lead author, said in a statement.

Neonics and their impact on the environment have been a topic of debate in Washington lately.

The US Environmental Protection Agency in May proposed a rule that would create temporary pesticide-free zones to protect commercial honeybees.

The restrictions are aimed at protecting honeybees, which pollinate plants that produce roughly a quarter of the food consumed by Americans. Losses of managed honeybee colonies hit 42.1 percent from April 2014 through April 2015, up from 34.2 percent for 2013-2014, and the second-highest annual loss to date, according to the US Department of Agriculture.

Beekeepers, environmental groups and some scientists say it is the neonics that are harming the bees.

Agrichemical companies including Bayer and Syngenta disagree, and instead blame mite infestations and other factors.

Read at: http://nypost.com/2015/08/18/insecticide-could-be-culprit-in-honeybee-die-offs/

USGS Summary: Insecticides Similar to Nicotine Found in About Haqlf of Sampled Streams Across the United States

Insecticides Similar to Nicotine Widespread in Midwest

USGS  July 24, 2014

Summary: Insecticides similar to nicotine, known as neonicotinoids, were found commonly in streams throughout the Midwest, according to a new USGS study

Insecticides similar to nicotine, known as neonicotinoids, were found commonly in streams throughout the Midwest, according to a new USGS study. This is the first broad-scale investigation of neonicotinoid insecticides in the Midwestern United States and one of the first conducted within the United States.

Effective in killing a broad range of insect pests, use of neonicotinoid insecticides has dramatically increased over the last decade across the United States, particularly in the Midwest.  The use of clothianidin, one of the chemicals studied, on corn in Iowa alone has almost doubled between 2011 and 2013.

 “Neonicotinoid insecticides are receiving increased attention by scientists as we explore the possible links between pesticides, nutrition, infectious disease, and other stress factors in the environment possibly associated with honeybee dieoffs.” said USGS scientist Kathryn Kuivila, the research team leader.

Neonicotinoid insecticides dissolve easily in water, but do not break down quickly in the environment. This means they are likely to be transported away in runoff from the fields where they were first applied to nearby surface water and groundwater bodies.

In all, nine rivers and streams, including the Mississippi and Missouri Rivers, were included in the study. The rivers studied drain most of Iowa, and parts of Minnesota, Montana, Nebraska, North Dakota, South Dakota, and Wisconsin. These states have the highest use of neonicotinoid insecticides in the Nation, and the chemicals were found in all nine rivers and streams.

Of the three most often found chemicals, clothianidin was the most commonly detected, showing up in 75 percent of the sites and at the highest concentration. Thiamethoxam was found at 47 percent of the sites, and imidacloprid was found at 23 percent. Two, acetamiprid and dinotefuran, were only found once, and the sixth, thiacloprid, was never detected.

Instead of being sprayed on growing or full-grown crops, neonicotinoids can be applied to the seed before planting. The use of treated seeds in the United States has increased to the point where most corn and soybeans planted in the United States have a seed treatment (i.e., coating), many of which include neonicotinoid insecticides.

“We noticed higher levels of these insecticides after rain storms during crop planting, which is similar to the spring flushing of herbicides that has been documented in Midwestern U.S. rivers and streams,” said USGS scientist Michelle Hladik, the report’s lead author. “In fact, the insecticides also were detected prior to their first use during the growing season, which indicates that they can persist from applications in prior years.”

One of the chemicals, imidacloprid, is known to be toxic to aquatic organisms at 10-100 nanograms per liter if the aquatic organisms are exposed to it for an extended period of time. Clothianidin and thiamethoxam behave similarly to imidacloprid, and are therefore anticipated to have similar effect levels. Maximum concentrations of clothianidin, thiamethoxam and imidacloprid measured in this study were 257, 185, and 42.7 nanograms per liter, respectively.

The U.S. Environmental Protection Agency has classified all detected neonicotinoids as not likely to be carcinogenic to humans.

The paper, “Widespread occurrence of neonicotinoid insecticides in streams in a high corn and soybean producing region, USA” and has been published in Environmental Pollution. Learn more about the study and the long-term USGS effort to gather information on the environmental occurrence of new pesticides in different geographic, climatic, and use settings here. To learn more about USGS environmental health science, please visit the USGS Environmental Health website and sign up for our GeoHealth Newsletter.

U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192

Alex Demas
Kathy Kuivila 

Insecticides Similar to Nicotine Widespread in Midwest

Insecticide Causes Changes In Honeybee Genes, Research Finds

(The following is brought to us by the American Bee Journal.) 7/1/13

New research by academics at The University of Nottingham (UK) has shown that exposure to a neonicotinoid insecticide causes changes to the genes of the honeybee.
 
The study, published in the scientific journal PLOS ONE, supports the recent decision taken by the European Commission to temporarily ban three neonicotinoids amid concerns that they could be linked to bee deaths.
 
There is growing evidence connecting the decline in the honeybee population that pollinates one-third of the food that we eat, and insecticides, but this is the first comprehensive study to look at changes in the activity of honeybee genes linked to one of the recently banned neonicotinoids, imidacloprid.
 
The study, led by Dr Reinhard Stöger, associate professor in Epigenetics in the University’s School of Biosciences, was conducted under field realistic conditions and showed that a very low exposure of just two parts per billion has an impact on the activity of some of the honeybee genes.
 
The researchers identified that cells of honeybee larvae had to work harder and increase the activity of genes involved in breaking down toxins, most likely to cope with the insecticide. Genes involved in regulating energy to run cells were also affected. Such changes are known to reduce the lifespan of the most widely studied insect, the common fruit fly, and lower a larva’s probability of surviving to adulthood.
 
Dr Stöger said: “Although larvae can still grow and develop in the presence of imidacloprid, the stability of the developmental process appears to be compromised. Should the bees be exposed to additional stresses such as pests, disease and bad weather then it is likely to increase the rate of development failure.”
 
The study was funded by The Co-operative Group, as part of its Plan Bee campaign.
 
Chris Shearlock, Sustainable Development Manager at The Co-operative, said: “This is a very significant piece of research, which clearly shows clear changes in honeybee gene activity as a result of exposure to a pesticide, which is currently in common use across the UK.
 
“As part of our Plan Bee campaign launched in 2009 we have adopted a precautionary approach and prohibited the use of six neonicotinoid pesticides, including imidacloprid, on our own-brand fresh and frozen produce and have welcomed the recent approach by the European Commission to temporarily ban three neonicotinoid pesticides as this will allow for research into the impact on both pollinators and agricultural productivity.”
 
The research paper Transient Exposure to Low Levels of Insecticide Affects Metabolic Networks of Honeybee Larvae is published in PLOS ONE.

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What Happened to the Bees This Spring?

(The following is brought to us by the American Bee Journal.) 

Subscribe to the American Bee Journal and sign up for ABJ Extra
 

Randy Oliver, commercial beekeeper and scientist, has investigated and summarized the factors involved in colony losses this winter, including the contribution of pesticides. In this lengthy two-part analysis he has obtained many opinions from both commercial beekeepers and scientists.

By now, most everyone has heard that honey bee colonies died in massive numbers this winter. Reporter Dan Rather, in his newscast Buzzkill, showed unfortunate beekeepers, some of whom had lost half or more of their colonies, predicting gloom and doom for the bee industry. What were the causes of this year’s bee shortage? As Rather says, “Everyone has an opinion.” The question is whether those opinions are based upon fact! So let’s go over the events leading up to the bee supply debacle.

Setting the Stage
Nearly 800,000 acres of almond trees in California came into bloom this winter—the trees typically start flowering about Valentine’s Day, and the bloom lasts for only about two weeks. Almonds require cross fertilization between adjacent rows of varieties, and honey bees are trucked in from all over the country to do the job (roughly a million and a half colonies). Many large commercial beekeepers move their hives into California in November to overwinter in holding yards; others build them up on winter pollen flows in Florida or Texas, or hold them in temperature-controlled potato cellars until shortly before bloom. The hives are generally placed into the orchards about a week before the first flowers appear. There is virtually no forage in the orchards prior to, or after bloom in many areas.

The Lead Up
Two seasons ago there was also a shortage of bees in almonds, following the coldest January (2011) in 17 years (cold being a major stressor of wintering bee colonies). Beekeepers then replaced their deadouts with package bees and splits, thus starting a new generation of colonies, which tend to have lower varroa mite levels than established colonies. These colonies entered autumn 2011 in pretty good shape, and then enjoyed the fourth warmest January (2012) on record! As a result, there was the lowest rate of winter mortality in years, and plenty of bees for almonds in 2012.

I was curious as to whether the colony loss rate was linked to the use of neonicotinoid insecticides. There is no recent USDA data, so I went through the California Pesticide Use Reports (data available through 2010). I plotted the amount of imidacloprid applied to crops in California in the preceding year in red (the seed treatment clothianidin didn’t even make the top 100 list of pesticides applied). Although there appears to be a possible correlation from 2006 through 2009, the trends were reversed for 2010. I will be curious to add the 2011 data when it becomes available.

In March of 2012 I received a phone call from a California queen producer who had a prescient insight as to a potential brewing disaster. He was receiving calls for queen bees from Northern beekeepers whose bees had already grown to swarming condition due to the unseasonably warm spring weather.

The queen producer noted that such early brood rearing also meant early mite buildup, and predicted that since most Midwestern beekeepers treat for mites by the calendar, that they would unknowingly allow mites to build to excessive levels before treatment. This was strike one against the bees.

To continue reading, click here: What Happened to the Bees This Spring?

Scientificbeekeeping.com  

EU Proposes to Ban Insecticides Linked to Bee Decline

The Guardian    By Damien Carrington  1/31/13

Three neonicotinoids, the world's most widely used insecticides would be forbidden across the continent for two years

Insecticides linked to serious harm in bees could be banned from use on flowering crops in Europe as early as July, under proposals set out by the European commission on Thursday, branded "hugely significant" by environmentalists. The move marks remarkably rapid action after evidence has mounted in recent months that the pesticides are contributing to the decline in insects that pollinate a third of all food.

Three neonicotinoids, the world's most widely used insecticides, which earn billions of pounds a year for their manufacturers, would be forbidden from use on corn, oil seed rape, sunflowers and other crops across the continent for two years.

It was time for "swift and decisive action"...

Read more...