The Neonicotinoids: An Objective Assessment

Scientific Beekeeping     By Randy Oliver     April 2018

(I wrote this article in response to a request following a presentation that I gave to the San Diego Master Gardeners. A revised version was later published by the University of California at http://ucnfa.ucanr.edu/files/280172.pdf)

Everyone’s heard about the claim that honey bees are going extinct due to the neonicotinoid insecticides. Although I’m glad that folk are concerned about the bees, the fact is that that claim is not accurate.

People have every reason to be concerned about our human impact upon the environment, and many species face extinction due to habitat conversion, pollution, overharvesting, and climate change. But the honey bee is not one of them. In actuality, the number of managed hives of bees has been increasing in recent years in nearly every country in the world. Colony numbers reflect the profitability of beekeeping as a business, as reflected in the graph below.

The largest number of hives in the U.S. occurred during World War II, due to the Army’s demand for beeswax, and the public’s demand for honey. After the War, beekeeping was less profitable, and the number of hives decreased. We then got hit by the introduction of two parasitic mites in the late 1980’s, and hive numbers declined further as it became tougher to keep our colonies alive. In recent years, the offered price for hive rental for almond pollination tripled, so colony numbers are on the rise.

In the early 2000’s, our bees got hit by yet another invasive pathogen (Nosema ceranae), and the term “CCD” was used to describe the sudden collapse of colonies. But at the time we didn’t know what was happening, which allowed the claim that a new class of insecticides—the neonicotinoids—were responsible. It was a compelling narrative—was this a repeat of DDT causing the near extinction of the pelicans and raptors? I immediately started researching the subject, but found to my surprise, that the narrative didn’t fit the evidence. But that didn’t stop the anti-neonic bandwagon, and researchers switched from working on our main problem—the varroa mite—to trying to pin the blame on the neonics.

Although varroa was a hot topic upon its arrival in Europe and North America, scientific interest in the parasite was eclipsed during the CCD epidemic in the mid 2000’s by the sexier claim that the neonics were to blame.

Why The Neonics?

Growers have long used insecticides, many of which we now know are not at all environmentally friendly.

Since the founding of the EPA in the post Silent Spring era, we are taking a better look at the impacts of pesticides upon off-target organisms, the environmental fates of the products, and their long-term sublethal effects—especially upon humans. EPA has thus phased out the “Dirty Dozen” Persistent Organic Pollutants. And in recent years has revoked or restricted the use of a number of others. For example, the previously commonly-used organophosphate chlorpyrifos is no longer registered for use as a household bug spray.

The problem is, that as we limit the number of insecticides available to growers, pests develop resistance to regularly-applied products. That, and the fact that the vast majority of a sprayed insecticide never actually hits the intended pest—thus ending up in the air, water, and rest of the environment. Growers thus put pressure on the chemical companies to continually develop new types of pesticides, while the consumer demands safer products.

Enter The Neonicotinoids

The neonicotinoids (meaning new, nicotine-like) are synthetic derivatives of the natural plant alkaloid nicotine. The neonics affect specific receptors in the nervous system of insects that are less prevalent in vertebrate animals, so they are thus much safer for humans, other mammals, birds, and fish. In fact, the most commonly-used neonic, imidicloprid, is less toxic to humans than is caffeine.

The second advantage of the neonics is that they are systemic—they can be absorbed through a plant’s roots, and get carried via the xylem to the rest of the plant. Thus, if they are applied as a seed treatment, the only organisms exposed to the chemical are the pests that take a bite out of the plant, or consume the pollen or nectar (this is where bees enter the picture).

Because of these advantages, neonics quickly became the most widely-used insecticides in the world.

Effects Of Neonics On Bees

Neonics are ideally applied as seed treatments, where the amount per seed can be carefully controlled, so that by the time that a plant produces nectar and pollen, the residues are too diluted to harm pollinators.

Unfortunately, during the introduction of the neonics, there were some serious incidents of inadvertent bee kills when the seed coating rubbed off in pneumatic seed planters, and the dust killed bees. In most countries, this issue has now been resolved.

This leaves the question of neonic residues in nectar and pollen. In general, the residues in the nectar and pollen of properly-treated agricultural crops (typically less than 3 ppb) do not appear to cause significant adverse effects on honey bee colonies. I’ve personally visited beekeepers in corn, soy, and canola growing areas, and they report that since the Bt genetically-engineered crops and the neonic seed treatments, that the pesticide issues that they suffered from in the 1960’s and ‘70’s have largely gone away. That said…

The Neonics Are Not Without Problems

Insecticides by definition are designed to kill insects. No insecticide is environmentally harmless, and as we learn more about unintended effects, our regulators must revise the approved allowable applications.

We have now found that the honey bee colony is a special case, and is able to “buffer” the sublethal effects of the neonics on the colony. So although properly-applied neonics appear to generally cause minimal measureable adverse effects on honey bee colonies, they may have more deleterious effects upon bumblebees and solitary native bees. This is a serious concern, of which the EPA is well aware.


Another concern is that with the widespread prophylactic use of neonic seed treatment, more and more residues are ending up at the field margins and in aquatic ecosystems. We’re recently finding out that certain uncultivated plants in the field margins concentrate neonic residues in their nectar and/or pollen. A recent study in Saskatchewan found residues up to 20 ppb in some flowers—enough to start causing problems in bee hives (serious problems occur at 50 ppb), and strong adverse effects upon some native pollinators. These unintended effects upon native pollinators and aquatic invertebrates need to be addressed, and the universal use of treated seed should be restricted.

 

I’m heartened by a recent Court ruling regarding a challenge to EPA, which apparently did not consult with the FWS or the NMFS regarding its approval of some registrations of clothianidin–see https://www.courthousenews.com/wp-content/uploads/2017/05/epa-pesticides-ruling.pdf

Uses Other Than As Seed Treatments

Neonics can also be applied as sprays, drenches, or other foliar applications, or by chemigation. There is far more room for misapplication by these methods. And perhaps worst of all would be misapplication by homeowners, who think that “if a little is good, more might be better.” Luckily, in the studies I’ve seen, urban and suburban bee-collected pollen and nectar normally does not contain toxic levels of neonics.

And this brings us to neonic applications in nursery stock. Nurserymen, in order to ship stock across state lines, must produce pest-free plants. This requires insecticides. But nurserymen do not want to expose their employees and customers to residues of organophosphates such as chlorpyrifos. They can avoid this by placing a measured amount of a neonic in the potting soil, which then, due to its systemic action, results in “clean” plants, and no human-harmful residues. Ideally, by the time a pollinator-attractive plant produces flowers, the residues would be diluted enough so as not to cause harm. The problem is, that no one has individually tested the thousands of cultivars of nursery plants. Plus there is no list of which cultivars attract pollinators.

There have been consumer protests at the big box nurseries, and nurserymen are scrambling to figure out answers.

Jim Bethke and I are currently involved in an IR-4 Project at Rutgers University to address this issue. Currently, we can’t really say which nursery plants might be problematic for pollinators. However, you can generally check a garden book to see if a cultivar is attractive to bees or butterflies; if so, at this time you may wish to avoid pollinator-attractive neonic-treated potted plants, and plant from seed instead.

Wrap Up

No insecticide is harmless. All of agriculture should shift towards Integrated Pest Management to reduce its reliance upon pesticides. California is the most proactive state in the Nation as far as safe pesticide use. The ag community and chemical companies have gotten the message loud and clear that the consumer wants them to reduce pesticide use and develop more eco-friendly pesticides—both of which they are doing.

Write to your representatives to support the EPA, which our current administration is attempting to shut down. Support local eco-friendly growers. Buying “organic” may help, but the best future will be the adoption of agro-ecology, which goes beyond “certified organic.” The field of agroecology is based upon biology, soil improvement, and sustainability, rather than upon “certified organic’s” arbitrary rules that exclude precision breeding and environmentally-friendly synthetic pesticides, fertilizers, and practices. Keep in mind that it is the housewife who spends her dollars at the grocery store who can effect the most rapid change—even the largest agribusinesses respond immediately to consumer demand.

http://scientificbeekeeping.com/the-neonicotinoids-an-objective-assessment/

More Reading

http://scientificbeekeeping.com/the-extinction-of-the-honey-bee/

http://scientificbeekeeping.com/neonicotinoids-trying-to-make-sense-of-the-science/

http://scientificbeekeeping.com/neonicotinoids-trying-to-make-sense-of-the-science-part-2/

 

Scientific Beekeeping: Research on Oxalic Acid

Scientific Beekeeping     By Randy Oliver     February 22, 2018

 Hi All,

Thanks so much for your feedback on the mite model--I received over 700 responses, many with constructive comments that I forwarded to the class.  Voting went overwhelmingly to the original graph--596 for it; 26 for the individual graphs; 11 for both.  I suggested to the class a way to present all options--taking first-time users step-by-step, with options.

I'm heartened by the number of you worldwide who have already used the mite model.  Your feedback and notes of appreciation make my day!

I'm currently deep into cage trials to attempt to determine the optimal formula for the extended-release oxalic acid treatment.  I'm trying different ratios of OA to glycerin, as well as using the very similar food-grade solvent propylene glycol.  I'm finding that both humidity and degree of saturation of the towels can make huge differences in whether the treatment hurts the bees.


I've also figured out how to quantify the precise amount of oxalic acid on the bees' bodies using titration:


I'm able to accurately quantify the amount of OA to less than 1/10,000th of a gram!  I now know how much OA is harmful to the bees, and will soon resume testing to see how little is necessary to kill the mites.

I've recently posted three new articles:

Not surprisingly, the first is Progress Report #3 on the above topic of the extended-release oxalic treatment.

The next two are numbers 14 and 15 in my "The Varroa Problem" series.
One discusses in-hive virus dynamics and the need for early mite treatment.
The other models the expected effect of various mite treatment options, especially repeated oxalic acid vaporizations (would also apply to sugar dusting).

Here at home, our beekeeping season is well underway.  Almond bloom in California is nearing an end, just as frosty air moved in to threaten the nutlets with freezing.  We've suddenly gone from a balmy early spring, to winter conditions.  Indeed, we started grafting queen cells as it was snowing.  My sons Eric and Ian are doing a great job at taking over the operation--we went to almonds with our highest colony count yet, and graded at over 15 frames average in those orchards that got graded per contract--giving them a nice bonus!

Happy Beekeeping to All!

Randy

(Please note: Randy Oliver's research on oxalic acid is supported entirely by donations from beekeepers.)

http://scientificbeekeeping.com/

Randy Oliver (Scientific Beekeeping) to Speak at BASC & Orange County Beekeepers Association

Thursday, Friday, and Saturday, September 28, 29 & 30, 2017, come learn about bees and beekeeping with Randy Oliver (Scientific Beekeeping). 

When: Thursday, September 28th, 6:30pm-8:55pm
Where:
La Mirada Civic Center (Resource Room)
Cost: (FREE)
Randy Oliver will be speaking at the September meeting of the Beekeepers Association of Southern California. (See details/flyer below and here.)

Friday, September 29th, 7:00pm (doors open at 6:30pm)
Where: OC Fairgrounds (Silo Building)
Cost: $5.00
Join Randy Olliver and the Orange County Beekeepers Association at the OC Fairgrounds. (See details/flyer below and here.)

When: Saturday, September 30th, 9am-4pm
Where: The Irvine Ranch Education Center,
Cost: $40 / $50. 
Orange County Beekeepers Association Event.

Randy will present a full day disease and pest management workshop, intermediate beekeeping topics, also covering other common problems such as insufficient honey or pollen stores, and a hands on demonstration. You have got to see Randy handle a hive - he's amazing!

$40 registration fee for members of the OC club. $50 registration for non-members so bring a friend. Sack lunch and drinks will be provided. Seats are limited to 35 so don't delay. Sign up here http://events.r20.constantcontact.com/register/event?oeidk=a07eejcjz002b0afc0f&llr=uikx5dkab

Thursday, September 28, 2017
BEEKEEPERS ASSOCIATION OF SOUTHERN CALIFORNIA
La Mirada Civic Center
Resource Room
13710 La Mirada Blvd.
La Mirada, CA 90638

6:30pm-8:55pm
Friday, September 29, 2017
ORANGE COUNTY BEEKEEPERS ASSOCIATION
 OC Fairgrounds
88 Fair Drive (Silo Building)
Costa Mesa, CA 92626 

7:00pm

Saturday, September 30, 2017
ORANGE COUNTY BEEKEEPERS ASSOCIATION
 Irvine Outdoor Education Center
2 Irvine Park Rd.
Irvine, CA 92869
9:00am-4:00pm

Randy Oliver:

Randy is a regular contributor to the American Beekeeping Journal, owner/author of scientificbeekeeping.com, and one of the premier beekeeping speakers in the US. We are very fortunate to have him share his knowledge with us. This is a rare chance to ask questions of one of the most respected researchers in the field ! Join us and enjoy an informal presentation on Randy's latest research projects and hive management.

“I started keeping bees as a hobbyist around 1966, and then went on to get university degrees in biological sciences, specializing in entomology.  In 1980 I began to build a migratory beekeeping operation in California, and currently run around 1000-1500 hives with my two sons, from which we make our livings.

In 1993, the varroa mite arrived in California, and after it wiped out my operation for the second time in 1999, I decided to “hit the books” and use my scientific background to learn to fight back.  I started writing for the American Bee Journal in 2006, and have submitted articles nearly every month since then (see “Articles by Publication Date”–scroll to the bottom for the most recent).

My writing for the Journal brought me requests to speak at beekeeping conventions, which has also allowed me the chance to visit beekeepers from all over North America and several other continents.  I read most every scientific study relating to beekeeping, and regularly correspond with beekeepers and researchers worldwide.

What I try to do in my articles and blogs is to scour scientific papers for practical beekeeping applications, and to sort through the advice, opinion, and conjecture found in the bee magazines and on the Web, taking no positions other than to provide accurate information to Joe Beekeeper.

I regularly update the articles on this site as new information becomes available, and solicit constructive criticism or comments.  Perhaps the best venue for such discussion is at the Informed Discussion of Beekeeping Issues and Bee Biology.  Be sure to subscribe to updates, and I’ll email you monthly when I add content to the sitehttp://scientificbeekeeping.com/scientific-beekeeping-newsletter/

Understanding Colony Buildup and Decline Part 1

Scientific Beekeeping.com   By Randy Oliver   First published in February 2015

During my recent trial of the pollen subs, I was able to watch small colonies recover and rebuild the moment that natural pollen became available. But there are intrinsic limits to how rapidly a colony can grow. An understanding of the factors involved can help us to manage colonies most effectively.

At my last writing, I was freshly returned from an inspection of our five worst yards. We had left those yards thoroughly depressed, and I feared that we’d need to change our name to “Diminished Expectations Apiaries.” Luckily, after I sent the article off for publication, we checked the next 35 yards, which were in far better shape, leaving us in the state of being “guardedly optimistic” (my sons’ new favorite term).

There being no time to waste, we immediately hopped on mite management (a combination treatment of...

Continue reading at http://goo.gl/L6NqiA

Honey Bee Decline A Buzz Kill For Agriculture

NBC Nightly News    July 25, 2014

July 16: Honeybees, which pollinate much of the U.S. food supply, have been vanishing, mystifying scientists and frustrating farmers. NBC's Anne Thonpson reports on the story first looked at by Nightly News last year.

 

 http://www.nbcnews.com/video/nightly-news/25706138#55680798

Bee Bits - Randy Oliver

Nevada County Beekeepers Association Newsletter - June 2014  Bee Bits, Randy Oliver, Contributor

As this odd season progresses, it just keeps getting stranger and stranger. Normally, I observe our Himalayan blackberry to begin flowering at my low-elevation yards on McCourtney Road a full month before my higher elevation yards around GV and NC. But last week the vines were at exactly the same stage of flowering in both areas. What this presages for our honey flow, I have no idea, but the foragers that I observed appeared to be filling their crops with nectar, and I’m able to shake nectar that tastes like blackberry from colonies in some yards. So I’m guardedly optimistic.

Water for bees will likely be an issue this summer. I suggest that you train your bees to water sources now, before they get hooked on the neighbor’s bird water bath. A plastic wading pool with a drip of water, aquatic plants, and floating chunks of pine bark is attractive to bees.

On the pesticide forefront, Dr. Lu of Harvard Medical School released another “study” claiming that neonics caused CCD. Again, his methods and conclusions are an embarrassment to the scientific method of investigation. I posted a critical blog at http://scientificbeekeeping.com/news-and-blogs-page/. Of interest is that after posting my critique, I received appreciative emails from bee researchers from across the country, who thanked me for publicly saying what they felt themselves. Politics are such that many of them feel constrained from saying embarrassing things about a Harvard researcher. Amusingly, one reporter called me and said that he had first interviewed Dr. Lu, and then phoned the USDA lab for their take on Lu’s findings. The reporter told me that the USDA had referred him to me; he was curious why our top researchers would steer him to a beekeeper out in the sticks : )

I’m currently writing a series of articles for ABJ covering the history of honey bee domestication, and how this has led to the problems that we’re having with bees today. My current article will come out in the June and July issues, and includes some very interesting findings about the genetics of our feral survivor stocks. These findings suggest to me that we should be paying far more attention to those “wild” colonies of bees that have been able to survive despite the impact of varroa.

On the bee nutrition front, the large trial that I ran over the winter clearly demonstrated the benefit of feeding pollen sub in the foothills. But there didn’t appear to be any added benefit when natural alder pollen was coming in. I’m starting a new trial this week to confirm that hypothesis. Thanks to those members who helped me set it up.

If you haven’t supered up your hives for the honey flow as of yet, I suggest that you do it now! I have no idea whether the honey flow will be weak or strong, or short or long, but if you don’t provide the bees with a place to store surplus honey, they won’t be able to do so.

I’m always interested in grafting from “survivor stock”—colonies that are productive, gentle, and that have survived for at least two full seasons without mite treatment. Please let me know if you have one (colonies on movable combs only—not bee trees—as I need to be able to graft from a brood comb).

Read Randy Oliver's blog about Dr. Lu's study of neonics and CCD at: 
http://scientificbeekeeping.com/news-and-blogs-page/
Read more from Randy Oliver at: http://scientificbeekeeping.com/

 

Useful Links

Following are some useful links that were shared at last night's LACBA meeting:
How to Reduce Bee Poisoning from Pesticides
Bee Informed Tech Transfer Teams - surveys, sampling, analysis, diagnostics
Randy Oliver's website, Scientific Beekeeping:

 

 

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