APIS Volume 10, Number 12, December 1992
In this issue
- Taking Stock in 1992
- Pheromonal Control and Swarming
TAKING STOCK
It's December again. Every year at this time, I try to summarize the last eleven issues of this newsletter. This is the 119th consecutive monthly issue of APIS to come off the press, continuing the tradition the newsletter has enjoyed for many years as one of most frequent and long running publications of its kind in the country.
Like so much in modern life, change in beekeeping is accelerating. This year was marked by a new apiary law, and the passing of Ralph Wadlow, one of the last of Florida's old-time beekeeping pioneers. With the realization that the Varroa bee mite is here to stay, its more and more apparent that the era of the let-alone beekeeper (beehaver) has come to an end. It's time to stand back, reflect a little, and take a deep breath before the tide of events determinedly washes us into 1993.
This year began with a report in APIS on deliberations of the Honey Bee Technical Council, advisory body to the Florida Commissioner of Agriculture. At that time, the Council ratified the concept of a registration/inspection fee. This set the stage for the new Apiary statute which became law in July.
Also in January, the Model Honey Bee Certification Plan drafted in St. Louis, MO, was published in this newsletter. It has two basic elements: (1) bee diseases/mites and (2) African bees. Beyond certification (disease treatment, mite quarantine, queens, cells, etc.) issues, the recognition that various kinds of beekeepers (non-migratory, interstate, queen and package producers) require different regulations was also addressed. It is expected that in the future, some form of this plan will be adopted by most states. The Honey Bee Technical Council has requested that the Division of Plant industry draft a similar document for Florida.
The February issue of APIS outlined the Lyme Disease situation in Florida and provided recipes for supplementing honey bee protein needs. Egyptian beekeeping, its history and current status, was featured in March. Possible problems discovered in Israel while relying on fluvalinate for mite control highlighted the April edition.
Two extensive articles concerning informing the public about the African bees were published this year (May and August). The latter contained a sample letter which could be sent to fire chiefs informing them about their possible role, as perceived by the public, in dealing with wild or feral honey bees. In May and November, the consequences of air pollution on citrus (and by extension, nectar production in those trees) were described. The June issue was a potpourri: it discussed honey freshness, formation of the Caribbean Apicultural Development Association (CADA), why honey bees are poor pollinators in some situations, and the Florida Forest Stewardship Program.
The July APIS provided feedback from bee inspectors concerning extender patty technology (also mentioned in the August issue) and formic acid dangers. The entire September issue focused on bee breeding and the one for October concentrated on the antibiotic properties of honey, New Zealand Manuka Honey and evidence of resistance to Apistan in Italy.
Finally, last month (November), this newsletter listed the rules of the new Florida apiary law and analyzed the changing patterns in bee inspection this might portend. In addition, it reported the disquieting news that a compatibility problem might exist when using mite control products [Miticur (R) and Apistan (R)] in concert
ESTABLISHING ORDER--SWARM CONTROL
We've been hearing a lot about the New World Order lately. The term has many meanings, depending on what part of the earth is discussed: Somalia, India, Serbia. Whether countries themselves, the United Nations or the United States consider taking action when things get out of control, the goal is always the same, to establish order. The perennial questions are what kind is needed and how is it to be preserved. After all, even chaos (most dictionaries define this as "disorder") mathematicians now tell us, has order.
How many have looked at the random movement of honey bees in a colony and seen only chaos? It is amazing that out of what at first glance appears to be random movement by thousands of individual insects, wonderful organizational patterns emerge. This confounded the ancients, who no doubt gave the credit to a panoply of gods. Researchers, using the tools of modern science, however, are constantly finding new clues about how order is established in a honey bee colony. That the source of much of it is from the queen is no surprise, but the details are often beyond our experience.
It is now definite that certain chemicals, called pheromones, regulate many of the activities of social insect societies. In "The Essence of Royalty: Honey Bee Queen Pheromone," (American Scientist: Vol. 80, No. 4, pp. 374-385, July-August 1992, M. Winston and K. Slessor state that some 36 pheromones have been identified in honey bees. Those of the queen, called primer pheromones, have long been thought to control the colony. Studies suggest they suppress queen cell construction by the colony and also block ovarial development in worker bees. There is also evidence queen pheromones attract workers (and drones) and stimulate foraging.
Early research in this field first identified two chemical compounds, 9-keto-2- decenoic acid (9ODA) and 9-hydroxy-2-decenoic acid (9HDA), found in the mandibular glands of queens as possible candidates for queen pheromone. These, particularly the latter, were often referred to as "queen substance." Although these compounds were active, the authors state that when synthesized, they did not fully duplicate the effects of mandibular gland extract.
It remained for the authors to discover that adding three more chemicals (two of completely different structure) made a pheromonal complex that was equivalent to mandibular gland extract. They emphasize that all the components are necessary for this royal essence to work; removing any one reduces activity by up to 50 percent. The component blend will vary with age. Virgin queens have practically none of these pheromones, only secreting the full array after being mated and laying eggs. Finally, the authors state that several other glands secrete chemicals that play a role in queen pheromonal communication.
Once the components of queen pheromone had been established, the authors proceeded to test for function. They found the pheromone complex suppressed queen rearing, attracted workers to the cluster and caused them to congregate together, and stimulated brood rearing and foraging. The latter might be the best commercial application of queen pheromones, as worker attractants in crop pollination. In a surprising development, the authors were unable to show that the pheromone supressed worker bee ovarial development.
A final part of the pheromonal puzzle concerned how the chemicals reached all workers in the colony. The authors were able to confirm what many have long thought. That bees in the royal retinue surrounding the queen transfer the pheromones from her to themselves and thence to their sisters. Two types of bees were identified by the authors: lickers and antennators. The former disperse most of the pheromone; why there are two kinds of workers in the retinue is a mystery. The comb wax also picks up some pheromone which is later transferred to other workers. The question of how the bees detect the pheromones remains unresolved.
The authors were surprised to find that almost all the queen pheromone produced ends up internalized both in the queen's and workers' bodies. The route can be through either the mouth or the skin (cuticle). This internalization may be one reason the queen produces so much pheromone. The authors suggest there might be a push-pull in worker-queen conflict. In order to escape the queen's chemical control, workers quickly try to absorb and break down (catabolize) the regulating chemicals. At the same time, the queen attempts to manufacture more pheromones to increase her dominance. This is analogous, the authors contend, with many families and societies that show a blend of cooperation and conflict, with some objectives in common, but individuals having their own goals as well.
Much of the dynamics in queen-worker conflict happens in swarming. Only when insufficient amount of pheromones are present will workers begin to rear queens. Given a queen that is constantly producing these controlling chemicals, the possibility exists for a reduction in pheromone only as colonies expand their population. A time is reached where there simply is not enough pheromone to go around, particularly if more and more is being internalized by greater numbers of workers. The authors were able to delay swarming by adding pheromones to the nest either impregnated in stationary blocks or as a spray. Reducing swarming, therefore, is thought to be another possible commercial use of royal essence.
The application of queen pheromones to control swarming is described further by Y. Lensky and P. Cassier in "Control of Swarming by Queen Bee Pheromones," BeeScience, Vol. 2, No. 1, pp. 7-11, March, 1992. The authors contrast emergency or supersedure cells being constructed in the nest's center (source of queen pheromones lost or very reduced) with swarm cells being built on the edges (queen pheromones not reaching the periphery). They determined a two-stage process in the latter process: (1) queen cups are constructed where a queen can lay an egg and (2) the cup with its egg is then transformed into a queen cell.
The authors confirm that as the worker population grows and nest congestion develops, the tendency to swarm increases. This is especially true when the queen's movement is restricted. They go one step further, however, by concluding that another pheromone is acting together with chemicals from the mandibular gland to suppress queen rearing. This is an oily substance emitted from the queen's feet that she leaves on the comb. The paper describes the structure of the gland that produces the queen's footprint substance.
Although unable as yet to prevent swarming using pheromone application, the authors have developed a procedure calculated to decrease it. They have minimized the production of new queens and thus reduced swarming by (1) annual requeening, (2) increasing the volume of hives by adding supers in excess, 3) raising 7 to 8 brood frames from the brood nest into the supers above the queen excluders, (4) preventing overheating by providing additional openings to help ventilation and (5) providing a constant water supply in the bee yard. This technique takes into consideration most of what is known about the pheromonal order established by queen honey bees, but one always ready to be undermined by the workers they control.
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (904) 392-1801, Ext. 143 FAX: 904-392-0190
http://www.ifas.ufl.edu/~entweb/apis/apis.htm
INTERNET Address: MTS@GNV.IFAS.UFL.EDU
©1992 M.T. Sanford "All Rights Reserved
