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Die-off

By Dick Marron (Dickm)

The first time I heard the word, I was studying population control within groups of mammals. The relationships between some predators and their prey are a self- adjusting rhythm. I’m thinking here of rabbits and deer and their predators. When the rabbit population expands so does that of the (let’s say) foxes. At some point there are too many foxes for the area and the rabbit population diminishes. As you would expect, the fox population follows with a dip of its’ own. When the foxes get low enough, the rabbits start to increase. They are good at that! The cycle repeats.

What do you suppose happens if all the foxes are killed off in one stroke? Rabies, for instance, could do that. A rabbit clan in this situation will go only just so far (in reproducing) before they start to damage the food source. About that time a die-off occurs. For a time the fields will be littered with rabbits that died for no apparent reason. They will be a little under normal weight and with adrenals over developed. That is all investigators can say about them.

The same thing happens with deer. A population of deer overcrowded an island where they were being studied. A sudden die-off occurred and the population was reduced. Low body weight and abnormal adrenal function was found there. It appeared as if the creatures were under stress. (Long term stress affects the adrenal glands.)

In rat studies an enclosed population was allowed to increase. At a certain population level they lost their basic instincts. Mothers abandoned their young and mating rituals were absent; there were other abnormalities, and the population crashed.

There are cycles within cycles and these occur within cycles too big to notice except in a bigger picture–the alternating ice-ages for instance. Humans tend to think in terms of the seasons. Not everything is yearly, however.

There are 13 year and 17 year cicada. When it’s their year and the soil temperature is between 64F and 68F they emerge from the ground, flourish for a few weeks and go back underground. Oh yes, they mate while they are out in the air flourishing. The mated adults lay eggs which become nymphs. The adults then die. The nymphs drop from the trees to the earth, burrow down and settle in for a nap (of 17 years) and a bit of suckling on a root. And you thought your life was dull! It is believed that the mass emergence of the cicada is part of a survival strategy. With so many of them, they collectively overfeed their predators within a few days. Then the billions left uneaten are free to mate. Also, there is no time for predator build up.

For more see:
http://news.nationalgeographic.com/news/2004/03/0329_040329_cicadas_2.html
For excellent pictures see:
http://biology.clc.uc.edu/steincarter/cicadas.htm

Look for cicada brood XIII in ’07. This emergence will be in Eastern IA, Northern Illinois, Southern Wisconsin, and along the southern edge of Lake Michigan. Dense populations will emerge in woods, forest preserves and along rivers as well as in suburban Chicago backyards.

This was a lot of two-finger typing to impress you with some of the lesser known strategies of nature and the cycles in which they occur. There are many more. You are already glad I’m keeping this short. I’m hoping this has something to do with bees.

OK here it is. They do have a mechanism we call “absconding.” (When my ex-wife did it I had another word). Whatever is bothering the bees, they leave it behind. That includes of course, their old (possibly polluted) comb; it also includes Varroa in the brood and a dozen or so viruses and fungi.

Since die-offs seem to happen every once in a while, at least since 1915, perhaps there is a rhythm at work–and we are too close to the woods to see the trees. Maybe the bees are dying in a sort of a mass absconding. Certainly a lot of varroa died too; perhaps everything but American Foul Brood (AFB), which, like the cicada, will wait for years.

Could this be evidence of a master plan? I didn’t think so either. Is it something to think about perhaps? Is it an artifact of the ease of communication in the bee world? (Someone will say this; it may as well be me.)

This was the sort of speculation I was writing when I left CT for FL. in Jan 07.

I went there to look at “Fall Dwindling.” It changed to “Colony Collapse Disorder” (CCD) while I was there. They could have called it “Death.”

First I learned what it was.
In a very short time a colony or a bee-yard will go from healthy and active to dead. There are plenty of stores. There may be capped brood. There may be a few bees left in the hive and a laying queen. These will always be young bees. There are no dead bees in the hive. No bees go into it to rob even where other hives exist in the area. Small hive beetles avoid the deadout hive. Wax moths also avoid it. It seems to be contagious, yet 100 yards away another yard may be untouched.

For a quick look at where things were in Dec. 06 go to: http://maarec.cas.psu.edu/pressReleases/
PrelimReportFallDwindle.pdf
for a preliminary report fielded by Maarec. People on the east coast and elsewhere were reporting losses of from 20 to 80%. Imagine losing 80% of 13,000 hives. It happened. Let me establish now that this is not limited to the east coast although Fl and PA are hard hit and are pushing the ball to get it rolling.

So there I was, in Florida. Jerry hooked me up with Todd. Todd sent me to Dave. Dave said come on up! Dennis will be here. Want to come along? OK so I’m name-dropping. Suffice it to say I wound up in the belly of the beast on the “Dwindle” phenomenon. Of course it wasn’t that any more. As I said, it’s Colony Collapse Disorder or CCD now because it started long before fall. What were the other names I dropped? Todd Jameson is a bee inspector for the Tampa area. Dennis van Engelsdorp is acting Chief Apiarist for the Dept of Agriculture in PA. He is also researching with the University of PA.

Jerry Hayes told Dave Hackenberg that he was either famous or infamous-they had named a disease after him. He (Dave) was the first one to report it. What Dave says, is that he was just the first one to open his mouth. He’d heard a story, months earlier, from someone in another state with high losses that didn’t cry “Dwindle!” That person didn’t want the “gubmint” to get involved because “they never help anyway.” I wonder how many held back information in the beginning because losing bees is not something beekeepers usually brag about. I suspect there may have been others that didn’t want to be put under a microscope.

Dave and his son Dave are running something less than 5,000 colonies. They pollinate and make honey as far north as the Canadian border and end up in PA. From there they move back to FL in the fall. They had one load of 2900 colonies dwindle to 1400 and they are still going down. They used cobalt radiation on 960 boxes of empty comb in hopes of reducing pathogens; they are feeding High Fructose Corn Syrup (HFCS) and pollen supplements. Young Dave had just one question. “Can someone tell me what to do?”

On Oct 11 they made up 400 splits (divides) of good strong bees in the Pa. yard. Mite counts were very low. These were good “four-framers.” He brought them down to Florida and dropped them. On Nov. 12 there wasn’t a bee to be found in that bee-yard. He’s been at this for forty years and this was a shocker. In the words of Dave senior: “I’ve never seen anything like it.”

In two days (Jan. 28 & 29) we looked at half a dozen yards owned by as many people. Some had mites but most didn’t. We looked at strong yards, mixed yards and mostly-dead yards. Anyone that thinks this is due to sloppy beekeeping or not keeping on top of the mites, leave the room now. You won’t learn anything.

I should explain the “we.” On both days there were up to six people working with Dennis van Englesdorp. He flew in to do some investigation. We were local beek’s with losses (or without losses) that chipped in, as well as some Florida bee inspectors–and this lone free lance writer. It still amazes me that two men could diagnose the strength of a four colony pallet of bees faster than I could write it down. These boys work hard.

First we would go through a yard and assess the stage the individual hives were at. We mapped the “strong” ones, the “dwindling and dying” ones and the “dwindling and recovering” ones. The fourth category was “dead.” In one yard of 248, 100 were dead and maybe 20 were strong. Of interest were the dwindled but recovering colonies. A few seemed to be making it back. This distinction between “on the way up” and “on the way down” seemed to be a fine one. I asked Dennis about that and he said that he’d learned to trust the beekeepers on things like that. The point is that some of the bees may be throwing this “disease” off.

I’m usually the guy with a joke in the group like I’ve described. I won’t say we didn’t have a laugh or two but I just couldn’t make light of what we were doing. It reminded me a little of being in a hospital hallway when someone you care about is in ICU. The best way I can describe the pace is grimly determined. It was a pace that kicked my butt and I wasn’t doing anything very physical. They are taking it as “It is what it is,” but everyone knows it isn’t over and no-one knows where it is going. I heard Dave take more than a dozen calls from other beekeepers presumably looking for information.

Knowing what is normal is of paramount importance in any investigation. A lot of stuff goes on in a bee colony that one could squint at and get on with ones work. Now, each slightly unusual thing gets scrutinized. I looked at a lot of bee guts laid out on Dennis’s wrist. There was normal, infection of the sting gland, wrong color and distended with pollen chunks. How much abnormality is “normal” in a bee colony? Good question.

There were dead bees collected that were chalky, slimy, incomplete, and decomposed. There was a little European Foul Brood (EFB). At one point a wet looking dead bee removed from a cell was placed in the middle of a frame of bees and the bees retreated from it as if it were poison. This happened two other times. Does it mean anything? What do you think? It was certainly not normal. Those bees will be analyzed. There were dead bees with fungus growing on them, all too quickly. All of these samples are headed for serious study. There are bees in alcohol and bees frozen in foil. There are samples of comb with brood, honey and pollen in evidence. We started cutting comb with a hot (therefore sterile) knife. We ended up bringing whole frames back to the shop so they could be sawn up. Ever try to cut plastic with a hot knife? In all, we examined about 1,000 colonies. They ranged from unaffected to every degree of distress.

Dennis has an interest in Aspergillus as the fungal pathogen. http://www.apimondia.org/apiacta/articles/2003/glinski_1.pdf
One variant is known to cause Stonebrood.
http://maarec.cas.psu.edu/bkCD/Bee_Diseases/Stonebrood.html
The assumption is that it may have mutated enough to act on the bees in a different and more deadly way. In addition it can create toxins in hive products that would explain why robbing is at a minimum as is predation by wax moths. (We did however see robbing going on, after comb had been aired out) Since this is a pathogen that attacks when colonies are weakened by other stressors, careful questions were being asked regarding moves, splits and mite levels. It does seem that hives that do not move in pollination do better but are not exempt. “What if it turns out to be many things,” Dennis wonders?

A major player on this stage is Jerry Bromenshenk, PHD. If you don’t know him, he’s a well known scientist from the University of Montana and his private company “Bee Alert.” He’s been using the sniffing talents of the honeybee in unique and creative ways. You’ve probably heard of the bees he encouraged to find land mines and other explosives. Next he wanted to imitate them. He is presently using a technology that will allow us to determine the health and other parameters (like queenlessness) of a hive by simply inserting a probe and sampling the airborne clues that reside there. A second probe analyzes the acoustic environment of that hive. He (and his “Bee Alert” company) has jumped into this with both feet and a crew of four. He and his equipment have been to CA, GA, FL, and PA–and back to CA. A major database has been developed from samples taken in these states. Surveys from 21 states are in it as well.

In his words: “. . . we’re looking to see if there’s a chemical inside the hives that appears with/after the collapse. One that may be the reason we see older bees, hive beetles, wax moths all leave — and that keeps everything away for 2-3 weeks (even robber bees) until it dissipates. I think we may have something that we’ve had all along, just never really got a handle on it. (It) flares up periodically . . . maybe something that all of the additional stressors that we now toss at the bees — foreign chemicals in the hive, movement from coast to coast, bad honey year, etc –pushes (them) over the edge.”

“Disappearing Disease” not only makes the bees disappear–like a cartoon cat eating its tail—it then disappears itself. It has been called: Spring Dwindling, Fall Dwindling, May Disease, and Autumn Collapse. The Isle of Wight Disease, first seen on that isle in 1904, had all the symptoms and is the only time a cause was supposedly found. (It was 17 years later). Maybe not. Read on. (From: http://apis.ifas.ufl.edu/apis91/apjun91.htm)

“Dr. Leslie Bailey, a renowned authority on bee diseases, called the “Isle of Wight Disease,” presumably caused by the tracheal mite, a myth (L. Bailey, “The ‘Isle of Wight Disease’: The Origin and Significance of the Myth,” Bee World, Vol. 45, pp. 32-37, 1964). Dr. Bailey said a primary reason for the notoriety of “Isle of Wight Disease” was sensationalized press releases which caught beekeepers’ attention.”

E. Oertel (1965) noted that the (disappearing) “disease” occurred in Louisiana from late September to early January when colony populations literally disappeared within a short time; only a “handful” of bees were left; honey stores were present; small amounts of pollen were sometimes present although pollen was generally absent; and brood rearing was almost nonexistent.

From Malcolm Sanford, 1984 http://apis.ifas.ufl.edu/apis84/apjun84.htm
“Another possible reason for slow population buildup in citrus groves may be just coming into focus. According to Dr. Randolph McCoy, University of Florida Agricultural Research and Education Center, Ft. Lauderdale, Florida, certain worm-like organisms called spiroplasmas have been found in flowers which are related to those implicated in a condition called “May disease,” in France. Again according to Dr. Shimanuki, “May disease” previously has implicated pollen of buttercups (Ranunculus species), and has had many names, including running about illness, running-in-the-sand sickness, frenzy sickness, wing paralysis, trembling sickness, flight incapacity, paralysis, and reeling sickness.”

Same Guy, 1994 http://apis.ifas.ufl.edu/apis94/apdec94.htm
“This fall many beekeepers have seen their colonies crash–the “disappearing disease.” Some have been wiped out, and the colonies went from very strong to dead in a very short time. The experts reported finding the same [those reported by Mr. Bach] viruses (chronic paralysis virus and Kashmir virus) in some of these dead colonies. So they associate these viral infections not with tracheal mites, but with Varroa mites. Are the viruses carried by one or both? Or are these viruses always present and their effect associated with stress from any source? It’s a frustrating yet fascinating time!”

Jim Tew: http://www.orsba.org/htdocs/download/Dtew.htm
“In 1915, after a particularly wet Spring, significant colony losses were reported. One beekeeper lost 400 hives. The problem was noted in multiple states from Florida to California. Hives came out the Winter in good shape, but adult bees began to vanish at the beginning of the Spring nectar flow.”

“From 1915 until this time, no single pathogen has even been isolated.”

“During the Spring of 2002, numerous Alabama beekeepers experienced an inexplicable bee colony die-off. There was no obvious cause – even after USDA analysis.”

Australia had a more or less yearly disappearing disease that wasn’t pinned to a pathogen. See “Denis Anderson,” below.

What could it be?
“Preliminary work has identified several likely factors that could be causing or contributing to CCD,” said Dennis van Engelsdorp, acting state apiarist with the Pennsylvania Department of Agriculture. “Among them are mites and associated diseases, some unknown pathogenic disease and pesticide contamination or poisoning.”

There are lots of possible candidates for CCD, ranging from the “new Nosema,” to Neonicotinoid insecticides, to Hydroxy-methyl-furfural (HMF) from bad corn syrup, even honeydew. Maybe we’ve got a new disease – it appears to be communicable. That said, the symptoms are exactly the same as seen in Louisiana and Texas and other states in the mid-60s. We have the same problem with identifying the cause; same guesses by beekeepers, etc.

When and where was/is it?
As of 2/2/07: It has been playing out all through 2006, and many beekeepers want us to go back at least two years. It seems to have started in the spring in MI, Iowa, WI (maybe other states), moved through the mid-west to the Dakotas early to mid-summer. It was on the east coast and SE in the fall. It hit places like Oklahoma hard last few weeks. Now seems to be in scattered locations throughout California. Oregon and Washington were just added to the list.

Nutrition:
Denis Anderson 1997, Australia (AU) http://www.rirdc.gov.au/reports/HBE/04-152.pdf “These results suggest that disappearing disorder may result from unusually high levels of trace elements in pollen and nectar collected by colonies in the affected areas. Further studies are needed to determine which trace elements might be responsible.” In 2001 there was a study in AU that concluded that poor acid soil either harbored a pathogen or didn’t put nourishment in the pollen. Bees were helped by trapping OUT the pollen and feeding supplements. Improvements were seen when Pollen was trapped OUT of the hive and supplements were fed. (As far as I know Denis doesn’t know of our troubles. I just thought these citations were tantalizing.)

Feed?
Beekeepers feed High Fructose corn syrup as a normal thing. It allows them to sell the honey and it makes a better winter feed because it has few residues. This is bought in tanker loads sometimes by groups of beekeepers and transferred to “Totes” to haul to the bees and is dispensed through a hose that looks a lot like a gas pump. Sometimes it needs to be stirred and every clever thing from outboard motors to air pumps has been employed to do this. Sometimes water needs to be added. When all is right with the world, it’s a reliable adjunct to beekeeping.

There are standards that the beekeepers require and the sugar people strive to meet. Otherwise bees will die. If a load doesn’t meet those specifications (is “Off Spec.”) some risk-takers may get a better price and feed it anyway. I’ve seen totes full of chocolate syrup. This has been its own lesson for a number of beekeepers—an expensive lesson. What if the load is off spec and no one knows it, even the producers? This has been problematic for decades. The fructose degrades and forms HMF. Heat accelerates this.

I spoke with Midwest beekeeper and author/researcher Bob Harrison. (His article on this subject may precede the one you’re reading.) He learned at the American Beekeeping Federation (ABF), and from others–that part of the problem with off-spec HFCS occurred because of temperature problems in transit. The material was being transported at too high a temperature. Beekeepers have been advised to check temperature of loads when accepting. In his words, “HFCS contains two sugars which shorten bees lives. In fact, kills bees when spiked into syrup in certain doses (Roy Barker USDA-ARS 1974). The sugars: Stachyose & Raffinose. These sugars are not found in sucrose.” Researchers vary in opinion but at least some feel that these sugars may occur in higher amounts in off spec loads. “Recent research done at the Weslaco Research facility (Dr. Pamela Gregory 2005/2006) found similar results when tests were set up using the research of Roy Barker as a guideline. In the bees fed the fructose, lifespan was much shorter than the bees fed the sucrose syrup.”

Rumor has it that this happened in Northern CA in 06. I couldn’t pin it down as a fact. Eric Mussen, Cooperative Extension Apiarist at UC Davis said: ”There are only observations that shortly after some colonies were fed HFCS they collapsed. However, given this winter, the bees could very well have collapsed if they had been fed sucrose syrup. Sometimes, stimulating a very unhealthy population of bees to begin brood rearing before adequate pollens are available leads to their collapse. We have no data.”

Pesticides:
Neonicitiniods are a class of pesticides that came out in 1985, produced by the German company, Bayer. They are related to nicotine and like that drug, they operate on the nervous system. In insects they disrupt the nerve channel which results in death. Gaucho contains Imidacloprid which is one of the more popular forms. It is used on seeds but is taken up by the plant. See http://www.bulletinofinsectology.org/pdfarticles/
vol56-2003-051-057maus.pdf for some Bayer sponsored research. This drug was thought to be the cause of massive die-offs in France (May disease) years ago. It was supposed that affected bees could not navigate home from the fields.
http://www.beekeeping.com/articles/us/imidacloprid_bayer.htm Other Neonicotinoids are: acetamiprid (Assail), imidacloprid (Gaucho,Admire,Provado), thiacloprid (Calypso), and thiamethoxam (Actara).

The report on bee-deaths, published by the French Comité Scientifique et Technique (CST) 2003, shows that the use of the pesticide GAUCHO is jointly responsible for the death of hundreds of thousands of bee colonies. Environmental activists and beekeeper unions are calling for a ban on the agricultural toxin. The summary of the report states: “The results of the examination on the risks of the seeds-treatment GAUCHO are alarming. The treatment of seeds by GAUCHO is a significant risk to bees in several stages of life.” The 108-page report was made by order of the agricultural ministry of France by the universities of Caen and Metz as well as by the Pasteur Institute. http://www.newmediaexplorer.org/sepp/2003/11/26/
millions_of_bees_dead_bayers_gaucho_blamed.htm The writer read a lot of old newsblogs on the subject. Here’s a chilling line from one of them: “The researchers also found traces of Imidaproclid in neighboring plants that were not treated by the pesticide.” Gaucho was banned in France until a reassessment could be done in 2006. The ban was upheld in Apr of 06

Fungus/Virus
Since it seems to be communicable any number of pathogens could vote themselves a place at the table. Aspergillus, the fungus that causes Stonebrood is a bad actor. (There are many strains) In humans it can kill, especially those that have compromised immune systems. There is, for instance, a form of Meningitis attributed to this fungus. As mentioned elsewhere, Dennis is working this angle if only to eliminate it. It’s not news to the researchers but may be news to the casual reader that the bees normally carry a number of viruses that do not seem to affect them. Some of them were found but not in enough places to point a finger. If the problem were a compromised immune system, one supposes it could be all of them. Scarring on the innards and black residue in the sting gland point to the possibility of infection, as does crystalline structures found in wing muscles and “kidneys”.

Mites
There are always mites. All of the original reports were from migratory beekeepers. They get together and swap strains of mites and disease. Then of course these bees are weakened by moving and splitting making the effects more deadly. Parasitic Mite Syndrome (PMS) mimics a number of diseases. The trouble is that this doesn’t seem to be a brood disease. It’s killing the older adult bees and they are dying far from home. Heavy mite loads in the fall can make the formation of a cluster of good strong “winter” bees unlikely. (I was just learning about PMS when my “Ex” absconded.)

Environment? Weather?
The comb has become suspect. There are two ways this can happen. Either the comb is so laced with the many pesticides and acids that it affects the longevity of the bees, or the aging combs have a heavy load of virus with the same effect. Some beek’s have irradiated comb. I’ve heard a theory about using ozone for this purpose. It is being researched. The 20 states reporting have had a variety of weather. If anything, the northeast, while having a reduced fall flow, did have warm temps late in the fall. It should have helped.

Nosema disease/Amoeba disease
While there is a new Nosema problem on the horizon, Nosema Ceranae, so far it’s not widespread, as far as we know. Sept: 2006:

“Yet another ‘new emerging or invasive pathogen’ threatens our honeybees. It’s Nosema Ceranae, similar to the well known Nosema Apis with which most of us are familiar. Unfortunately it seems that ceranae is likely to be worse than apis although at present the symptoms are not clear. It has been reported that Fumidil-B is apparently works against ceranae” (Mariano Higes, Spain, poster at the Eurbee conference in Prague, Sept 2006).

Jan 07: From the Georgia Bee Letter:

“Dr. Tom Webster at Kentucky State University has recently found Nosema ceranae in one of their KSU hives. This particular hive had migrated from Kentucky to Florida last October. Bees sampled in December tested positive for Nosema ceranae. The N. ceranae spores were also found in a Kentucky beekeeper’s operation whose colonies had migrated to Florida. Dr. Webster stressed that this information is extremely tentative at this point.”

Did that move fast, or what? For sure the “New Nosema” is a killer. Just Google “Nosema, Spain,” to learn about serious devastation there.

In researching this I heard of Nosema Ceranae in FL TN and KY but haven’t confirmed that yet. Dr Robert Paxton: Queen’s University Belfast, and his team developed a test that will discriminate the various Nosema genes. He’s looked for it and found it. His manuscript is unpublished at this point but he shared with me:

“Working at Queen’s University Belfast, Julia Klee, Andrea Besana and Robert Paxton have now demonstrated that N. ceranae is actually far more widespread and is found in western honey bees across the New World, Europe and Asia; their full report has been submitted for peer-review publication in the Journal of Invertebrate Pathology.
“. . . it has spread remarkably rapidly. It is found nowadays in the western honey bee in North and South America, the Caribbean, across Europe (from south to north and west to east) and Asia. Only on the islands of Ireland and New Zealand have we looked but found only Nosema Apis, We lack samples from Africa, Australia and (cannot) say anything about those locations. However: given its rate of spread and occurrence even on isolated islands of the Danish archipelago, it is quite possible that Nosema Ceranae: is, or will soon be, spread worldwide.” (From Bees for Development Journal (81))”

Bottom line: If it ain’t here it will be. We can’t convict it for CCD. Disassembled bees showed some digestive abnormalities but nothing constant. Nosema was not absent in samples but was not present in profusion. Amoeba disease is found in the Malphigian tubules (sometimes referred to as kidneys) and there was an occasional cyst only. On the other hand these tubules were abnormally swollen and discolored in many samples.

In short, for every candidate there is an opposing argument. Some of the best brains and equipment are being called into play, even some from those working in human medicine.
If you think the worry is limited to beekeepers, check out this almond grower site.

http://www.almondgrower.com/

The question that the younger David Hackenberg asked remains unanswered. “What can I do now?”


Dick Marron is a retired psychologist living in a bee-yard in CT. He would like to thank the following folks for their help.

Jerry Bromenshenk; Paul Burt; Bob Craig; Dennis van Engelsdorp; Jerry Hayes; Dave(s) Hackenberg; Bob Harrison; Todd Jameson; Eric Mussen Randy Oliver; Andy Miksa; Robert Paxton; David Westervelt