Environmental Blogs, Habitat, Ecology, Endangered Species


Frog Blog - Nature Science Research Ecology

Green Mutual Fund Investing Info

Chitika

Twitter / elephantfamily

Twitter / savethefrogs

These Come From Trees Blog

Monday, July 30, 2012

Give BEES a Chance



From the New York Times:


2 Studies Point to Common Pesticide as a Culprit in Declining Bee Colonies


Scientists have been alarmed and puzzled by declines in bee populations in the United States and other parts of the world. They have suspected that pesticides are playing a part, but to date their experiments have yielded conflicting, ambiguous results.
In Thursday’s issue of the journal Science, two teams of researchers published studies suggesting that low levels of a common pesticide can have significant effects on bee colonies. One experiment, conducted by French researchers, indicates that the chemicals fog honeybee brains, making it harder for them to find their way home. The other study, by scientists in Britain, suggests that they keep bumblebees from supplying their hives with enough food to produce new queens.
The authors of both studies contend that their results raise serious questions about the use of the pesticides, known as neonicotinoids.
“I personally would like to see them not being used until more research has been done,” said David Goulson, an author of the bumblebee paper who teaches at the University of Stirling, in Scotland. “If it confirms what we’ve found, then they certainly shouldn’t be used when they’re going to be fed on by bees.”
But pesticides are only one of several likely factors that scientists have linked to declining bee populations. There are simply fewer flowers, for example, thanks to land development. Bees are increasingly succumbing to mites, viruses, fungi and other pathogens.
Outside experts were divided about the importance of the two new studies. Some favored the honeybee study over the bumblebee study, while others felt the opposite was true. Environmentalists say that both studies support their view that the insecticides should be banned. And a scientist for Bayer CropScience, the leading maker of neonicotinoids, cast doubt on both studies, for what other scientists said were legitimate reasons.
David Fischer, an ecotoxicologist at Bayer CropScience, said the new experiments had design flaws and conflicting results. In the French study, he said, the honeybees got far too much neonicotinoid. “I think they selected an improper dose level,” Dr. Fischer said.
Dr. Goulson’s study on bumblebees might warrant a “closer look,” Dr. Fischer said, but he argued that the weight of evidence still points to mites and viruses as the most likely candidates for bee declines.
The research does not solve the mystery of the vanishing bees. Although bumblebees have been on the decline in the United States and elsewhere, they have not succumbed to a specific phenomenon known as colony collapse disorder, which affects only honeybees.
Yet the research is coming out at a time when opposition to neonicotinoids is gaining momentum. The insecticides, introduced in the early 1990s, have exploded in popularity; virtually all corn grown in the United States is treated with them. Neonicotinoids are taken up by plants and moved to all their tissues — including the nectar on which bees feed. The concentration of neonicotinoids in nectar is not lethal, but some scientists have wondered if it might still affect bees.
In the honeybee experiment, researchers at the National Institute for Agricultural Research in France fed the bees a dose of neonicotinoid-laced sugar water and then moved them more than half a mile from their hive. The bees carried miniature radio tags that allowed the scientists to keep track of how many returned to the hive.
In familiar territory, the scientists found, the bees exposed to the pesticide were 10 percent less likely than healthy bees to make it home. In unfamiliar places, that figure rose to 31 percent.
The French scientists used a computer model to estimate how the hive would be affected by the loss of these bees. Under different conditions, they concluded that the hive’s population might drop by two-thirds or more, depending on how many worker bees were exposed.
“I thought it was very well designed,” said May Berenbaum, an entomologist at the University of Illinois at Urbana-Champaign.
But James Cresswell, an ecotoxicologist at the University of Exeter in England, was less impressed, because the scientists had to rely on a computer model to determine changes in the hive. “I don’t think the paper is a trump card,” he said.
In the British study, Dr. Goulson and his colleagues fed sugar water laced with a neonicotinoid pesticide to 50 bumblebee colonies. The researchers then moved the bee colonies to a farm, alongside 25 colonies that had been fed ordinary sugar water.
At the end of each year, all the bumblebees in a hive die except for a few new queens, which will go on to found new hives. Dr. Goulson and his colleagues found that colonies exposed to neonicotinoids produced 85 percent fewer queens. This reduction would translate into 85 percent fewer hives.
Jeffery Pettis, a bee expert at the United States Department of Agriculture, called Dr. Goulson’s study “alarming.” He said he suspected that other types of wild bees would be shown to suffer similar effects.
Dr. Pettis is also convinced that neonicotinoids in low doses make bees more vulnerable to disease. He and other researchers have recently published experiments showing that neonicotinoids make honeybees more vulnerable to infections from parasitic fungi.
“Three or four years ago, I was much more cautious about how much pesticides were contributing to the problem,” Dr. Pettis said. “Now more and more evidence points to pesticides being a consistent part of the problem.”

Thursday, May 17, 2012

Neonicotinoids cause massive honeybee deaths


by Heather Pilatic
In the last few weeks beekeepers have reported staggering losses in Minnesota, Nebraska and Ohio after their hives foraged on pesticide-treated corn fields. Indiana too, two years ago. What's going on in the Corn Belt?
No farmer in their right mind wants to poison pollinators. When I spoke with one Iowa corn farmer in January and told him about the upcoming release of a Purdue study confirming corn as a major pesticide exposure route for bees, his face dropped with worn exasperation. He looked down for a moment, sighed and said, "You know, I held out for years on buying them GE seeds, but now I can't get conventional seeds anymore. They just don't carry 'em."
This leaves us with two questions: 1) What do GE seeds have to do with neonicotinoids and bees? and 2) How can an Iowa corn farmer find himself feeling unable to farm without poisoning pollinators? In other words, where did U.S. corn cultivation go wrong?
The short answer to both questions starts with a slow motion train wreck that began in the mid-1990s: Corn integrated pest management (IPM) fell apart at the seams. Rather, it was intentionally unraveled by Bayer and Monsanto.
Honey bees caught in the cross-fire
Corn is far from the only crop treated by neonicotinoids, but it is the largest use of arable land in North America, and honey bees rely on corn as a major protein source. At least 94 percent of the92 million acres of corn planted across the U.S. this year will have been treated with either clothianidin or thiamethoxam (another neonicotinoid).
As we head into peak corn planting season throughout the U.S. Midwest, bees will once again "get it from all sides" as they:
  • fly through clothianidin-contaminated planter dust;
  • gather clothianidin-laced corn pollen, which will then be fed to emerging larva;
  • gather water from acutely toxic, pesticide-laced guttation droplets; and/or
  • gather pollen and nectar from nearby fields where forage sources such as dandelions have taken up these persistent chemicals from soil that's been contaminated year on year since clothianidin's widespread introduction into corn cultivation in 2003.

GE corn & neonicotinoid seed treatments go hand-in-hand
Over the last 15 years, U.S. corn cultivation has gone from a crop requiring little-to-no insecticides and negligible amounts of fungicides, to a crop where the average acre is grown from seeds treated or genetically engineered to express three different insecticides (as well as a fungicide or two) before being sprayed prophylactically with RoundUp (an herbicide) and a new class of fungicides that farmers didn't know they "needed" before the mid-2000s.
A series of marketing ploys by the pesticide industry undergird this story. It's about time to start telling it, if for no other reason than to give lie to the oft-repeated notion that there is no alternative to farming corn in a way that poisons pollinators. We were once -- not so long ago -- on a very different path.
How corn farming went off the rails
In the early 1990s, we were really good at growing corn using bio-intensive integrated pest management (bio-IPM). In practice, that meant crop rotations, supporting natural predators, using biocontrol agents like ladybugs and as a last resort, using chemical controls only after pests had been scouted for and found. During this time of peak bio-IPM adoption, today's common practice of blanketing corn acreage with "insurance" applications of various pesticides without having established the need to do so would have been unthinkable. It's expensive to use inputs you don't need, and was once the mark of bad farming.
Then, in the mid-to-late 1990s, GE corn and neonicotinoid (imidacloprid) seed treatments both entered the market -- the two go hand-in-hand, partly by design and partly by accident. Conditions for the marketing of both products were ripe due to a combination of factors:
  • regulatory pressures and insect resistance had pushed previous insecticide classes off the market, creating an opening for neonicotinoids to rapidly take over global marketshare;
  • patented seeds became legally defensible, and the pesticide industry gobbled up the global seed market; and
  • a variant of the corn rootworm outsmarted soy-corn rotations, driving an uptick in insecticide use around 1995-96.
Then, as if on cue, Monsanto introduced three different strains of patented, GE corn between 1997 and 2003 (RoundUp Ready, and two Bt-expressing variants aimed at controlling the European Corn Borer and corn root worm). Clothianidin entered the U.S. market under conditional registration in 2003, and in 2004 corn seed companies began marketing seeds treated with a 5X level of neonicotinoids (1.25 mg/seed vs. .25).
... and in the space of a decade, U.S. corn acreage undergoes a ten-fold increase in average insecticide use. By 2007, the average acre of corn has more than three systemic insecticides -- both Bt traits and a neonicotinoid. Compare this to the early 1990s, when only an estimated 30-35 percent of all corn acreage were treated with insecticides at all.
Adding fuel to the fire, in 2008 USDA's Federal Crop Insurance Board of Directors approved reductions in crop insurance premiums for producers who plant certain Bt corn hybrids. By 2009,40 percent of corn farmers interviewed said they did not have access to elite (high-yielding) non-Bt corn seed. It is by now common knowledge that conventional corn farmers have a very hard time finding seed that is not genetically engineered and treated with neonicotinoids.
Enter fungicides
In 2007, what's left of corn IPM was further unraveled with the mass marketing of a new class of fungicides (strobilurins) for use on corn as yield "boosters." Before this, fungicide use on corn was so uncommon that it didn't appear in Crop Life's 2002 National Pesticide Use Database. But in the last five years, the pesticide industry has aggressively and successfully marketed prophylactic applications of fungicides on corn as yield and growth enhancers, and use has grown dramatically as a result. This despite the fact that these fungicides work as marketed less than half the time. According to this meta-analysis of efficacy studies, only "48% of treatments resulted in a yield response greater than the economic break-even value of 6 bu/acre."
Back to the bees. Neonicotinoids are known to synergize with certain fungicides to increase the toxicity of the former to honey bees up to 1,000-fold, and fungicides may be key culprits in undermining beneficial bee microbiota that do things like make beebread nutritious and support immune response against gut pathogens like Nosema. Fungicide use in corn is likewise destroying beneficial fungi in many cropping systems, and driving the emergence of resistant strains.
As with insecticides and herbicides, so too with fungicide use on corn: Corn farmers are stuck on a pesticide treadmill on high gear, with a pre-emptively pressed turbo charge button (as "insurance"). Among the many casualties are our honey bees who rely on corn's abundant pollen supply.
Keeping us all tethered to the pesticide treadmill is expected behavior from the likes of Monsanto. But what boggles the mind is that all of this is being aided and abetted by a USDA that ties cheap crop insurance to planting patented Bt corn, and a Congress that refuses to tie subsidized crop insurance in the Farm Bill to common-sense conservation practices like bio-intensive IPM. Try explaining that with a waggle dance.


Heather Pilatic is Co-director, Pesticide Action Network North America

Thursday, February 2, 2012

New Pesticides May Be Killing Off Honeybees

by Molly Cotter, Inhabitat.com





Since 2004, the number of honeybees in the U.S. has been nearly cut in half. While similar massive declines are prevalent around the world, scientists are still trying to figure out what exactly is causing the disappearance of the honeybees. A new study by the U.S. government’s premier bee expert Dr. Jeffrey Pettis suggests that nicotine-based chemicals found in popular pesticides have a dangerous effect on exposed bees and could be a major contributor to the missing bee mystery.

Bees pollinate 70% of the world’s crops, and their diminishing presence is detrimental for farmers all over the world. Dr. Pettis spent months researching bees exposed to neonicotinoid chemicals and found even the tiniest amount made them three times more vulnerable to infection. The pesticide chemical attacks bees’ immune systems, weakening their bodies and often times confusing them, leading bees to wander away and lose their colonies.

The chemicals are very popular, and they were considered an environmental breakthrough because they can be applied to the seeds of a crop rather than the plant. While this and other studies bring pesticide issues to light, others believe the bee population decline to be related to weather, developmental, or evolutionary survival issues.

Natural World Search Engine; Ecology, Environment and Scientific Websites



Search Engine for Nature and Environment Websites

Best homework tool, research scientific papers, find ecology info online, nature and environment websites, environmental blogs, natural world studies, ecology and politics, green energy activism, environmental movement, clean energy, environment and ecology research.

Custom Search


A cool Blog for all Frog Lovers

Nature and Ecology Links, Environmental Books, Nature Groups




Twitter / RBKC_Ecology

21st Century Architecture

Sacred Elephants

Twitter / Vertigal