“EAS Goes Global in Georgia”

Bee Culture (October 2006) Vol. 134 (10): 17-19

Dr. Malcolm T. Sanford

Young Harris College in the town of the same name, and nestled in the Northeast Georgia mountains, hosted the 51^st meeting of the Eastern Apicultural Society (EAS), the first ever in the Peach State. The organizers were surprised that it was oversubscribed (361 people showed up), but it was no shocker that President Jennifer Berry and the busy worker bees of the Georgia Beekeepers Association put on a great show. Although somewhat focused on a rather small part of the region’s colorful history, making illegal spirits (participants at the hog roast received a shot glass engraved with “Let the Georgia Moon Shine on You”), there was plenty of evidence that the global economy has reached this part of the world. One only has to look at the number of Tex-Mex restaurants in the region, and listen to the strains of Mariachi norteños on the local radio stations to realize that “times they are a changing.”

Several themes provided a more worldly emphasis as well. The presence of the infamous Africanized honey bee in Florida (AHB) was one focus of the meeting, and so was current situation with reference to queen breeding (the Russians have arrived), Varroa mite taxonomy and resistance possibilities via news from Australia. Finally, there as emphasis on international standards for the honey show with two certified judges in attendance, one each from Ireland and Wales. The bottom line is that the depth and quality of information provided at this conference gets better each year.

Jerry Hayes, Florida’s chief apiarist, told those in attendance that it’s no longer if, but when the more “defensive” AHB will show up on the eastern beekeepers’ doorstep. His message: Beekeepers and regulators had better be ready, for the situation is rapidly heating up in the Sunshine State, and this could provide a nucleus of bees that could rapidly infest the rest of the eastern seaboard. He sees the biggest problems from this insect as not management by the beekeeper, but public relations with the 99.99 percent of people in the state who are not into working with stinging insects. As such Florida’s Department of Agriculture has pulled out all the stops and embarked on an ambitious plan to educate everyone in this urban state about the benefits of honey bees and most importantly, the potential ally that the beekeeper managing white boxes is in limiting invasion opportunities for AHB. To see an example of activities in this area, one can look at those of the AHB Interagency Coordination Group.¹

Under normal circumstances, bringing somebody from as far away as Australia to educate beekeepers would seem counterproductive, given that beekeeping is really a local phenomenon. But this is clearly not so when the organism in question is the Varroa bee mite, a globally-distributed organism that has radically transformed beekeeping over the last three and a half decades. Because Australia is the last land mass of any significant size to be affected by this mite, one might also assume that little research on the critter itself would be required apart from efforts to exclude it. However, Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO), approximately equivalent to USDA’s Agricultural Research Service, has employed Dr. Anderson,² who specialized in bee pathology for much of his education, to get a handle on this pest’s biology before it shows up “Down Under.”

Using good old-fashion detective work, and incorporating newfangled technology (DNA analysis), Dr. Anderson has been able to piece together an engaging story that he regaled the audience with peppered by Aussie accent and euphemism. Several clues led to the fact that the mite originally described in 1904 as Varroa jacobsoni is in fact not the one that is causing havoc across the beekeeping world. Two observations led to further investigation. Some Varroa did not reproduce on the western honey bee, Apis mellifera, including Varroa jacobsoni itself as first described from Java, and the mite causing the biggest problems was a lot larger than its jacobsoni cousin. From this beginning, it is now known that the genus Varroa is a large complex of mites distributed across Asia containing many genetically similar races (genotypes), rather like honey bees themselves. However, the Varroa mite complex does not have the same cosmopolitan characteristics as the Apis mellifera one, the latter being far more able to reproduce among its genetic variants (ecotypes). Over twenty different Varroa called “haplotypes” have been identified. Amazingly, all are associated with specific Apis cerana hosts in their native range, but only two have actually made the jump from their original host to the western honey bee, Apis mellifera. These are the virulent Korean and more benign Japanese haplotypes, now renamed Varroa destructor by Dr. Anderson and colleagues.

When the biological basis for separating these mites is better understood, Dr. Anderson said, the next step will be to find out what allows some mites to reproduce on Apis mellifera, but not others. Once discovered, this should lead to developing truly Varroa-resistant as opposed to simply Varroa- tolerant western honey bees. Dr. Anderson believes the mechanism is a specific chemical signal or signals that literally switch on mite reproduction. If the mites do not receive the signal, they do not reproduce, ending their life cycle. Thus, two possibilities come to mind, selecting for bees that do not produce the proper reproductive signal or using genetic engineering to develop bee strains whose signals mites cannot recognize.

Finally, Dr. Anderson spoke eloquently about how Varroa destructor affects honey bees. There is a recognized pathology associated with the mite that consists of several possibilities. The first, of course, is collectively the effects of the mites themselves as they feed on developing bees. Clearly pupae that are heavily fed on (parasitized) by mites cannot develop normally. This “mechanical damage” leads to all kinds of conditions, including: weight loss, wing deformity, low protein content, shrunken brood food glands, less sperm in drones and runty queens.

However, the question remains, according to Dr. Anderson, whether the above situations themselves lead inevitably to colony death. Another host of problems comes from pathogens that Varroa is affiliated with, especially viruses. Some may be transmitted by mites, but others may simply be present in bees and “activated.” Dr. Anderson called the latter kind “inapparent viruses.” Some 18 viruses have been found in honey bees. Several are clearly associated with Varroa, including Kashmir bee virus (KBV), acute bee paralysis, deformed-wing virus, and cloudy wing virus. The problem is that these are little studied and their symptoms more often than not mimic those of mechanical damage as described above. Other pathological affects correlated with mites are suppressed immune systems, mite-produced foreign enzymes injected into bees, and stress, leading to other conditions (American foulbrood, chalkbrood), the newest organism affecting colonies, and small hive beetle (SHB) population buildup.

In conclusion, Dr. Anderson said that no one strategy can be to control all Varroa’s pathological effects, but in general, there is one with the most chance of accomplishing this on a broader scale. That is the time-honored one of controlling the mite population in bee colonies. This will have to be the goal of beekeepers until research reveals the reproductive “off” switch that he and others are feverishly searching for.

Part of the strategy suggested by Dr. Anderson is already being applied, but in a different manner by researchers at the USDA-ARS Baton Rouge, LA honey bee laboratory. This was relayed by Dr. John Harbo, recently retired from that facility, who assured the audience that he will now become a beekeeper in his own right so will be able to understand better the common problems of the general apiculturalist. Dr. Harbo is credited with finding specific populations of bees in the U.S. on which Varroa indeed does not reproduce. Originally, he attributed this trait to the ability of honey bees to influence mite reproduction, calling them SMR (suppressed mite reproduction) or “Smart”, terms still in use. However, more recently he discovered that mite reproduction itself was not reduced in bees showing the SMR trait. Instead some bees are much better at detecting and removing reproductive mites (and their associated bee pupae), while leaving non-reproductive individuals alone.

Thus, the SMR trait has now been renamed Varroa-sensitive hygiene (VSH). Two observations led to more insight about this trait. One is that reproductive mites deposit a fecal patch on the side of the cell; non-reproductive mites do it on the developing bee itself, providing a good signal to any human observer about a mite’s reproductive status. Another is that it appears to be a common attribute that 11% of female mites in general are not reproductive. Thus, the VSH trait can be fairly easily monitored and calculated, and it is both heritable and additive. Once the frequency of mites that lay no eggs is calculated, for example, one automatically knows the level of the VSH trait present in bees. Dr. Harbo concluded that just a few genes of the VSH trait placed by selection into a honey bee population could make a huge difference in how a colony copes with mites.

Reducing Varroa mite populations is best done using integrated pest management (IPM) , according to Dr. Keith Delaplane of the University of Georgia. This could be accomplished through other mechanisms beyond pesticide application, such as drone trapping and monitoring hygienic behavior, and reducing mite numbers using screened bottom boards. Employing only hygienic behavior and screened bottoms, Dr. Delaplane and colleagues have shown it is possible to get keep the mite population below the economic threshold (level at which they cause economic damage). The biggest problem with both these measurements is the time involved in sampling. Now that it is known that mite numbers can be radically effected by IPM, Dr. Delaplane says perhaps the best use of researchers’ and beekeepers’ time is to develop more efficient population-sampling procedures.

As was the case at last year’s EAS meeting in Kent, OH there continues to be great concern in the beekeeping community about the queen bee supply. One of Georgia’s traditional producers, Fred Rossman, discussed the status from his perspective. He “guesstimates” some 265,000 queens are produced each year in Georgia, making it second to California, with 75,000 going into package bees during April and May. The number of shippers is declining in the state with only about 20 being able to hang on at the present time. Huge challenges are affecting the industry, especially those surrounding shipping the insects. Only UPS will ship and the U.S. Postal Service continues to make it extremely difficult to continue this practice. Note letter in the August 2006 Bee Culture asking for support for SB 2395 by Gus Rouse of Kona Queen in Hawaii.

Dr. Steve Sheppard of Washington State University also discussed his latest findings concerning queen sources. Several historic “genetic bottle necks” have been identified that have served to produce a huge number of queens in the U.S., but with a narrow genetic diversity, which has been further reduced through loss of most of the feral population by Varroa predation. Only 9 out of 26 species of bees have much representation in the U.S. gene pool, and there is a large difference between those produced in the east versus the west. To increase diversity, Dr. Sheppard suggested more genetic material should be shared between geographic regions. Finally, if any genetic material is brought into the U.S. in an effort to maximize diversity, he concluded, that the best and least risky source would be from the bees’ Old World native ranges.

It is becoming clear that drones are also part of the queen supply equation. We now know that they are adversely affected by low levels of pesticide use in. In addition paternity makes a big difference when it comes to the process of Africanization. Dr. Greg Hunt of Purdue University in his discussion of managing this phenomenon indicated that although theoretically genetic crosses between European (EHB) and Africanized (AHB ) lines should not be affected by paternity, that is not the case from a practical standpoint. In general, EHB queens mated with AHB drones in everyway produce workers that exhibit more rampant African behavior than would be theoretically predicted.

A discussion of drone rearing by Dr. Larry Connor, owner of Wicwas Press, who says they are more important than you think, revealed the importance of feeding syrup and pollen for maximum production. He also provided information on sustaining drone holding colonies: four frames of target drones with four frames of brood and a caged virgin. These ideally could be set out 2.5 to .5 miles from the mating apiary. He detailed a two-year plan using 40 colonies incorporating five lines (survivor, Russian, SMR-now VSH, Minnesota hygienics and New World Carniolans).

Dr. Marion Ellis and students spent a summer looking for drone congregation areas (DCAs) on the University of Nebraska campus, and collected data suggesting that these are not randomly placed, but appear to coincide with linear objects that drones use as navigational aids rather than direction of the sun as employed by foragers. He concludes the best chance of finding a drone congregation area using a fishing rod and weather balloon with lure is at the end of long rows of evergreen trees at the University of Nebraska. As part of this study, he and his students found that drones were usually located further from colonies (3-5 kilometers) than queens (1-4 kilometers).

It is impossible to describe in one column the total the week’s activities in Georgia that encompassed both an EAS short course and conference program. Suffice to say it was full of both beekeeping and social activities. The latter included the southern hog roast featuring a welcome from a certain Confederate Colonel Forrest who regaled the “Yankees” in the crowd with a good dose of Southern humor, a low-country shrimp and sausage boil, and the final costume ball and banquet. The honey exchange, auctions, award ceremonies (Hambleton, Morse and Divelbiss) and master beekeeper examinations, and first-ever Jeopar-Bee Contest rounded out the event.

Next year EAS meets again in Delaware after a 10-year hiatus at the University in Newark, just off I-95. The theme is “Beekeeping – Inside & Out.” We already have a taste of the event provided in the Summer 2006 EAS Journal. If you join The Eastern Apicultural Society today (send a $25 check made out to EAS to the Treasurer, John Tulloch, P.O. Box 473, 211 High St. Odessa, DE 19730), you will receive a couple of other newsletters about the event before it occurs, August 6-10, 2007. I hope to see you there.

References:

<http://www.doacs.state.fl.us/pi/plantinsp/apiary/ahbgroup/>, accessed August 20, 2006.
<http://www.ento.csiro.au/staffhome/danderson.html>, accessed August 20, 2006.