IUSSI Meets in St

“IUSSI Meets in St. Petersburg, Russia: A Feast of Firsts, Parts I-III”
American Bee Journal (November 2005-January 2006), Vols. 913-914

Dr. Malcolm T. Sanford

http://apis.shorturl.com

St. Petersburg is the Russian Federation’s second largest and most European-like city with a population exceeding 4.5 million, fourth in size in Europe after Moscow, London and Paris. Constructed on the low-lying delta of the Neva River, this “Venice of the North” is characterized by several islands, many canals and over 600 bridges. It was constructed after a monk told the future Peter the Great to build a new capital in the north in honor of St. Peter. He also said that such a city and its people would be protected by the Kazan Icon, and could not be conquered. His prediction came true when the city (then called Leningrad) withstood 900 days of siege and bombing by the Nazis in World War II, while incurring horrific casualties and suffering, but did not fall.

The site of the new capital was determined when the Swedish city of Nienchschants surrendered in 1703 to Russian forces and a fortress was constructed near the mouth of the Neva to administer the newly-conquered territory. After Peter the Great’s historic tours of Europe, St. Petersburg became the symbol of Russia’s opening to Western Europe’s peoples and culture. Thus, it is the site of the first Russian museum, conservatory, public library, academy of arts and sciences and university.

It seems appropriate, therefore, that the first meeting of the European Section of the International Union for the Study of Social Insects (IUSSI) in Russia (the 3^rd European Congress) should meet at the University of St. Petersburg (22-27 August 2005), which was established in 1724. To give the meeting further significance it met in the university’s historic Twelve Collegiums (Ministries) on Vasilyevski Island, characterized by a series of twelve identical buildings, connected by a common corridor over 300 yards long. At one end is a library and at the other a painting showing Peter the Great signing the university into existence. The building’s long hallway is adorned with paintings and sculptures of notable Russian scientists like Mikhail Lomonosov (first Russian student of the natural sciences), Andrei Sakharov (father of the soviet H-bomb), and perhaps most celebrated, Ivan Pavlov, who developed the theory of learning through conditioned response.

Pavlovian learning in insects was in fact an unstated theme of the Congress. It was keynoted by Adrian Wenner, Professor Emeritus, University California at Santa Barbara and focused mostly on honey bees, although the other social insects, ants, wasps and termites also got their due. The meeting was also considered a collective attempt by social insect scientists in the rest of Europe to communicate with their colleagues in Russia, who are now beginning to emerge and flourish as the Soviet Union’s political domination and persecution of many scientists is on the wane. How powerful these influences were has been commemorated by a sculpture in the University’s courtyard dedicated to repression of the faculty during the Soviet era.

In a metaphoric way, Dr. Wenner too was ending his self-imposed isolation from bee research as part of this congress. He was clearly surprised that so much of his work has been recognized in Russia, when elsewhere it was at best ignored, at worst denigrated. The story of Dr. Wenner’s journey from high school principal and teacher to Professor Emeritus is long and complicated, and can be found in detail at the World Wide Web site: http://www.beesource.com/pov/wenner/ . He summarized some of it in his discussion, including rearing queens while working his uncles’ apiary that led him to suspect that sound would be better ways for bees to communicate the existence of food sources to their sisters rather than dancing in a dark hive. From this emerged the hypothesis that bees communicate their own experience via a dance, but do not pass it on to others through “language.” Thus began a three-decade struggle first within himself as he saw one of his cherished ideas (the honey bee’s dance language) shattered, and later with a majority of the scientific community who were unwilling to reconsider Dr. Karl Von Frisch’s experiments and conclusions when confronted with conflicting data.

Dr. Wenner provided three hypotheses at the Congress based on his work:

“Bees rely on a suite of odors, as well as on visual and other cues, but do not necessarily rely on a single chemical at any one time.” This is often the result of learning (conditioned response). Bees receiving a specific odor or suite of odors injected into the colony, for example, will return to empty dishes to which they were previously trained through use of these odors.
“Recruitment of experienced bees each day can be explained by conditioned response, a recruitment to wherever the odor of similar food sources exist in the region.” Experienced forager bees, for example, when receiving a familiar odor, immediately go to previously yielding sources (learning), while recruits arrive much later (a learning curve is required).
“Without odor, recruited bees cannot find a food source.” Switching to unscented food halfway through an experiment results in no further recruits. Odorless dishes and paraphernalia are difficult to make because odor is literally everywhere, and it only takes a few molecules to train bees. Wind also complicates foraging experiments as does distance from the hive of a scent. Finally, bees are easily distracted by a suite of odors in nature (nectar flow) stronger than those provided by investigators.

The above, Dr. Wenner concluded, could be used in practical applications that would encourage bees to forage on particular crops, something that many have worked on for decades with little success. This will, however, not be easy, because it must take into account the “full application of current knowledge about odor,” including influence of conditioned response (learning), wind and competing scents found in nature.

Mandyam Srinivasan and colleagues at the Australian National University provided a great deal of information on honey bee learning through some ingenious experiments that examined honey bees as they flew through tunnels. These revealed that bees don’t need a stereo vision mechanism because they estimate distance based on motion of images. “Flight speed is regulated by holding constant the average image velocity as seen by both eyes.” The insects also hold a constant image velocity with respect to the ground (horizontal surface), enabling them to gently “touch down” like airliners as they land.

The authors concluded that research “is beginning to reveal that these insects may not be the simple, reflexive creatures that they once were assumed to be.” Bees can learn general features of flowers and landmarks (color, orientation, symmetry), and apply them to distinguish between objects not previously encountered. They also exhibit “top-down” processing, learning to detect poorly visible and camouflaged objects, can navigate through labyrinths using symbolic signposts, and make associations such as “sameness” and “difference.”

Finally, in a statement that might have been written by Dr. Wenner himself, the investigators said bees have “associative recall,” that a familiar scent can trigger recall of an associated odor, or even of a navigational route to a food location. They concluded, “there is no hard dichotomy between invertebrates and vertebrates in the context of perception, learning and ‘cognition,’ and that brain size is not necessarily a reliable predictor of perceptual capacity.” A poster by Christoph Grüter and colleagues, University of Bern, also provides evidence of this. They concluded that “rapid distribution of food amongst hive members via trophallaxis leads to a fast propagation of olfactory information by means of associated learning, i.e. a large number of bees has been conditioned to a floral scent during food processing within the hive.”

Andrew Barron and colleagues, Australian National University and University of Illinois, explored the use of neurohormones, the bioamines serotonin and octopamine, on dance behavior. Their results when looking at five different dance components showed a dose-dependent effect using octopamine, but none for serotonin. The conclusion was that this kind of work will “open a new line of study on this communication system.” Perhaps this will provide additional valuable information on the various hypotheses surrounding dance language.

Ronald Thenius and colleagues, Karl-Franzens-University, Austria, reported that foragers returning with nectar loads hand it off to several receiving bees. An increase in multiple uploads does not only affect foragers on a single source, but also the whole cohort of forager and nectar-receiving bees. This provides evidence that there are unknown possible mechanisms via these multiple uploads that give the colony “global information” about its environment.

The symposium in the Congress on “Learning and Memory in Social Systems” was also overwhelmingly focused on honey bee research. A paper by Uli Müller, Saarland University, revealed that molecular machinery (cascades) and learning are interrelated. Another by Dorothea Eisenhardt and colleagues, Free University of Berlin, showed the basis behind memory formation was protein synthesis. Bern Grünewald of the same institution reported on cellular physiology changes in both the antennae and mushroom bodies of the brain due to conditioning stimulus (learning), and R. Menzel and P. Szyszka used “optophysiological recordings” to look at honey bee neurons themselves. Finally Dr. L.V. Rhzhova and colleagues from the famous Russian Pavlov Institute of Physiology presented information on glutamate receptors’ role in bee associative learning. Some receptors had a pharmacological profile similar to that found in mammals.

A related symposium, “The Molecular Bases of Social Behavior and Sociality,” also prominently featured honey bees. Charles Whitfield and colleagues, University of Illinois and France’s INRA, used an “integrated genomic approach to dissect natural behavioral maturation in the adult worker…” Three components of gene expression were identified:

Development of behavioral competency, complete by eight days.
Current behavior state (nurse or forager)
Experience

They concluded that gene expression was associated with behavior and not related to age or genotype. It was also regulated by modulators such as juvenile hormone and not “behavior-consequence experience or environmental differences.”

Christina Grozinger, North Carolina State University, studied queen mandibular pheromone’s (QMP) effect on the brain cells themselves. QMP inhibits worker ovarial development and slows transition for nursing to foraging. But it [QMP] stimulates foraging in a bee already determined to be in the forager state. Expression of two genes modulated by QMP (Fz2 and Kr-h1) was monitored over fours days in young bees, providing further proof that reactions to pheromones are not “hardwired,” and can be changed (modulated) by the state of the organism.

Charles Claudianos, Australian National University, and colleagues reported that honey bees have an unexpected 25-30% deficit in genes with a total of only 10,000. This is compared to both the vinegar fly (Drosophila) that has about 13,000 genes and mosquito, which has close to14,000. They suggested that the bee has reduced its dependence on genetic diversity by evolving more specialized nutritional and reproductive strategies as well as complex cognitive and social behaviors. They also found a small increase in the number and regulation of key neurological genes that may account for this shift. The downside is that “significantly reduced molecular diversity may place the honey bee at greater risk to environmental change including toxic chemicals.” This does not appear to be good news for beekeepers who are applying pesticides in colonies for Varroa control.

In a related paper, Michel Solignac, CNRS and colleagues from INRA, Saint-Gély-du-fesc , France provided information that the “linkage map” of the honey bee had been constructed in three steps with 1694 markers, and is now “saturated” (16 linkage groups). Once a candidate region is defined, the authors concluded: “…the density of markers increased in the region, and it is easy to get very close to genes of interest thanks to the relatively small physical size of the genome (230 megabases).”

Dr. Jozef Šimúth, Slovak Academy of Sciences and colleagues from Germany (Berlin and Halle/Salle) presented their evidence for using the honey bee as a model for functional genomics. The insect has several features that make it an ideal organism for the study of both applied and fundamental functional genomics. These include: haplo-diploidy, a caste system, slow ontogeny, rich behavioral potential, and high economic value. Specifically the authors suggested that several tools could now be developed such as those involved in characterizing disease resistance genes and stocks, and marker assisted selection for productivity of royal jelly proteins in vitro as well as other products used by the pharmaceutical industry. As an example of the above, K.A. Aronstein, Beneficial Insects Laboratory, Weslaco, Texas and colleagues have described a novel gene from honey bees (Am18w). They reported that this could be valuable in understanding how control is regulated in immune related molecules (anti-microbial peptides) among cells.

Dr. Šimúth presented a plenary lecture on the potential of using molecular techniques to better understand royal jelly constituents, which he listed as: enzymes, nutritional proteins secreted in the larval diet, protective proteins and peptides put into bee products like royal jelly that protect the colony against pathogens, and are physiologically active in stimulating the immune system. All these possibilities will become more easily explored, he concluded, with release of the honey bee genomic sequence. The results of the project so far can bee seen at (http://hgsc.bcm.tmc.edu).

IUSSI Meets in St. Petersburg, Russia: A Feast of Firsts, Part II

Dr. Malcolm T. Sanford

http://apis.shorturl.com

The history of St. Petersburg is a mixture of cultures, ideas and events greatly influenced by European ideas after Peter the Great returned from his legendary travels outside his country. The list of Russians who contributed to the city’s growth and prosperity featured in guidebooks for sale in this city is legion. These folks come from all walks of life, and encompass literature (Dostoevski and Pushkin), dance (G. Ulanova), music (Tchaikovsky), science (I. Pavlov), and others.

It seemed most suitable that the first meeting of the European Section of the International Union for the Study of Social Insects (IUSSI) in Russia (the 3^rd European Congress) would focus some energy on its own historical roots. This is especially true since it took place at the University of St. Petersburg, the first Russian university established in 1724, and the home of many ideas that have permeated western science, such as Pavlov’s conditioned learning response.

The IUSSI was established in 1952. It consists of a number of groups, including the Russian-speaking section that hosted the St. Petersburg Congress, and German-speaking and Spanish-speaking (Sección Bolivariana) sections among others. It also publishes the prestigious journal Insectes Sociaux. There is an international congress every four years, and the North American section will host the XV such congress in Washington, DC, July 30 to August 5, 2006. A series of symposia is already in the works, including: genes, genomics, social biology and biology; management of social insects; and a symposium on phylogeny and evolution of bees, dedicated to the noted biologist Charles Michener, who helped establish the concept of “euosociality,” characterized by reproductive specialization.¹

The study of sociality has only comparatively recently been a focus of insect biologists. Broadly speaking, there are four groups of “truly social” (eusocial) insects: ants, bees, wasps and termites. Study of these has also become more prominent in conjunction with the rise of “sociobiology,” a term coined by the famous ant biologist, E.O. Wilson, who will keynote the XV Congress in Washington, DC. Sociobiology remains a controversial topic, especially true when the principles found in insects and other organisms are applied to the human situation.²

In St. Petersburg, Christopher Starr, University of the West Indes, and IUSSI’s “archivist,” provided a list of eight open questions about persons and episodes in sociobiology, which he concluded “is an immensely rich field that has just begun to be written.” Punctuated with the participants’ popping caps from Russian beer cans, he explored the following in some detail:

Relationship between study in one species, the honey bee, and growth of sociobiology before 1800.
Réamur’s book on ants, though complete, remained unpublished and not mentioned by the author himself. Why not?
Public indifference to studies by König and Smeathman on “enormous nests of Macrotermes”(termites) in Africa.
The 19^th century Dzierzon-led movement to propagate his scientific approach to honey bee biology.
The Marais/Maeterlinck plagiarism dispute concerning articles on Macrotermes.
Pierre Paul Grassé’s leadership in the period after World War II.
The emergence of the concept of eusociality by Charles Michener.
Concepts of “kin-group” and “superorganism” are at odds, but peacefully coexist.

The majority of the above feature honey bees in some way or another. Both Maeterlinck and Michener studied bees as well other social insects. Certainly the accumulated knowledge about honey bees over the centuries has led to many of the current issues that swirl about insect sociobiology today. And that field is also expanding as more and more insects are now being observed through a “social lens.”

As an example, one of the main presentations at the Russian Congress was by Sumio Tojo and colleagues, Saga University, Japan concerning the shield bug, Parastrachia japonenses. This Japanese “stink bug” (Hemiptera) only feeds on one plant. Thus, there is little room for error in its life cycle, and so it has adapted a behavior close to full sociality, including synchronizing its reproduction with the plant’s, provisioning food for its young, aggregating during reproductive diapause (cold-weather inactivity), and possessing symbiotic bacteria that supply uric acid in the gut, which they cannot make themselves.

Sociality in honey bees has been studied a number of ways, including using sophisticated models. T. Schmicki and Carlo Crailsheim, Karl-Franzens-University, Graz reported on their simulation of task selection in honey bees. In an effort to add further evidence of sociality reported the literature, which is mostly subjective (abstract) and based on ant behavior, they created a honey bee colony simulation that “incorporated stimuli-threshold reinforcement mechanisms.” This refers to social insects regulating their division of labor in a decentralized way based on individual perceptions. Thus, if a stimulus in the colony exceeds a certain task-specific level or threshold for an individual, then it moves on to another job.

They used various stimuli including light gradients, brood pheromone, crop fillings, direct assessment of comb content (brood, pollen, nectar), dances (waggle and trembling) and temporal (queuing) delays to look at the dynamic between nurse and foraging bees. Their “simulated” honey bee colony was able to regulate brood nursing, and recruit nurses, nectar receivers and foragers just like in the real world.

The biogeography of honey bees has never been much of a focus for investigators in the United States, perhaps because funding for this kind of research is extremely scarce. In addition, the honey bee population in this country is a mixture of introduced races, impossible to separate into distinct groups or ecotypes. However, bee biodiversity remains of great interest to Europeans, who can examine native or indigenous honey bee populations.

Ibrahim Çakmak, Uludag University, Turkey revealed information on the various races of Apis mellifera found in Anatolia. These include A. m. anatoliaca (populations of this race also differ from east to west inTurkey), A. m. carnica (Thrace), A. m. armeriaca (convergence of the Black Sea, Ilgaz and Taurus mountain ranges), A. m. caucasica (eastern Black Sea), and A. m. syriaca in eastern Turkey, bordering Syria and Iraq. He concluded that honey bees in Turkey differ not only in morphometrics, but also in foraging behavior, and this diversity can be exploited in finding bees tolerant to diseases and pests. There is evidence, however, that hybridization between races is occurring at a rapid rate due to migratory beekeeping in the country. Fortunately, pockets of endemic bees can still be found managed by stationary beekeepers.

A.G. Nikolenko, Urfa Scientific Center, Russia, reported on the critical condition of the black European honey bee (Apis mellifera mellifera). Much of the decline in this subspecies has to do with habitat destruction; however, hybridization through migratory beekeeping is also taking a toll. Four intact local populations, nevertheless, have been identified based on immune response, measured by levels of antioxidants such as glyukozo-6-phosphatedehydrogenase. Immune responses, the author concluded, can be used to separate races and also be employed in breeding programs. Specific population buildup data for bees in Northwestern Caucasia, Krasnodar region were also reported by Larisa Moreva, Kuban State University, Russia.

In a creative departure from collecting experimental data, Alexander Komissar, National Agricultural University Ukraine, presented a paper based on anecdotal evidence entitled “Races of Honey Bees, Human Nations and Religions.” He concluded that the “distribution of the different aboriginal honey bee races in Europe coincides with the distribution of main religions.” Thus the Italian (A. m. ligustica) and carniolan (A. m. carnica) races are found in Catholic countries, while Macedonian bees (A. m. macedonica) are associated with countries of the Eastern Orthodox religion. He also said that dark bees (A. m. mellifera) are not compatible with Catholicism, and protestant countries use exclusively hybrid bees. Finally, no subspecies is “naturally distributed” simultaneously in Christian and Moslem countries with the exception of Albania. From this information, he postulated that the “introduction of foreign bee races to regions with inappropriate human religion can’t be successful,” and concluded that “maybe the use of appropriate races can harmonize human life.” In a disclaimer sentence, he stated that such a hypothesis is “outside of scientific understanding,” but so is much of religion, and thus it should not be discounted.

A symposium on swarming in honey bees somewhat paralleled that concerning biodiversity. Again Ibrahim Çakmak took the lead by reporting information on swarming by the various races of honey bees found in Turkey. A. m. caucasica swarms at most once a year in its native range, producing only ten to twenty queen cells, whereas A. m. carnica may cast as many as three swarms per season and builds more swarm cells. Both races, however, swarm far less than A. m. anatoliaca, even though they all appear to be adapted to cold winters in their native range.

Correlated with higher swarming rates in A. m. anatoliaca is a dry hot summer season. The same is true for A. m. syriaca, which swarms far more frequently and may build hundreds of queen cells. This is due to a combination of several things, including unpredictable weather (hot, dry desert conditions) and the fact that it does not have to store as much honey as bees in the north because the winter season is typically wet enough to promote vegetative flowering. In addition, this race is often challenged by an enlarged group of predators, including two wasps, known to kill entire colonies on occasion. Although not mentioned in the paper, this author would add the bee eating bird (Merops. sp.) to this list. Swarming to avoid predation, therefore, is not out of the question.

The above observations seem relevant to recent beekeeper discussions about Russian bees recently introduced into the United States. Users indicate these insects do not produce as much honey as hybrid bees currently in use, are much more difficult to requeen, and supersede quickly because they continuously build and tear down many queen cells. Beekeepers faced with this bee’s behavior, therefore, must adapt their management to its peculiarities to be successful.

The situation surrounding A. m. syriaca is instructive, given this author’s recent visit to Iraq where this bee in endemic. The traditional basket-like beekeeping in the country employs small colonies of honey bees and encourages them to swarm. This kind of management may be much more attuned to the bee’s biological adaptation than larger Langstroth-type colony management that is being introduced as a “superior technology.” .

The swarming situation is muddled, Dr. Çakmak said, “Swarming of bee colonies is known to be affected by a number of factors in the hive, which include the environment and genetics of honey bee race. However, the collective decision process of workers to swarm is not well understood.”

Enter the next presentation by Zbiginew Lipiński, “Emotional Nature of Adaptive Nest Abandonment by Honeybee Swarms.” Drawing on observations in other fields of neuroscience, the author explained that stress rather than reproduction is at the root of all swarming. His “nest abandonment” hypothesis indeed fits the many scenarios that appear to link swarming (often referred to as ‘reproductive’), migrating and absconding behavior. These may reflect a process, similar to the nurse-forager model described elsewhere in this article, which finally leads to release of migratory instinct by highly emotionally excited workers in shape of a swarm, especially due to insufficiency or lack of control of worker bee emotions by queen pheromones.

The use of the term “emotional” in the swarming context raises some eyebrows. A closer examination of his abstract in the proceedings and presentation at the Congress suggests that what Dr. Lipiński calls emotional might be simply “stimulation” or excitation of the central nervous system (CNS). He concluded that the most common behavior for all three types of nest abandonment by swarms (adaptive swarming, migrating and absconding) is stress-related engorgement with honey or nectar. Expression of other stress behaviors such as queen cell building, queen rearing, etc. depends, apart from genetic background of the bee, on type and intensity of a given stress swarm reaction. Thus, the emotional arousal of the bee brain and subsequent changes in its cognitive perception not only affect swarming, migrating and absconding, but other behaviors as well.

References:

Program of the XV International Congress on Social Insects, July 30 to August 6, 2006, Washington, DC <http://www.iussi.org/program.html>, accessed September 25, 2005.
Wikipedia, Free Internet Encyclopedia <http://en.wikipedia.org/wiki/Sociobiology>, accessed September 25, 2005.

IUSSI Meets in St. Petersburg, Russia: A Feast of Firsts, Part III

Dr. Malcolm T. Sanford

http://apis.shorturl.com

Every city has a rhythm and St. Petersburg, Russia is no exception. It is situated at a higher latitude (above the 60^th parallel) than any other great metropolis on the globe. Summers have very long days; the famous “white nights” in June and early July are considered a tourist attraction themselves. In addition, the many draw bridges spanning the Neva River are raised and lowered at specific times (between 1:30 and 5:00 a.m.) when vehicular traffic is at a minimum. The unaware tourist can easily be stranded. The population of the city is devoted to its night life, and the casual visitor’s daily routine also needs to be adjusted to this reality.

St. Petersburg is two times zones east of many other great European cities, like Paris, putting it 8 to 11 hours later than the U.S.’s Atlantic and Pacific coasts respectively. This means serious jet lag, a great shift in one’s own daily or circadian rhythm, for many arriving tourists and participants alike attending the 3^rd European Congress on Social Insects.

Insects also have circadian rhythm. Dr. Guy Bloch and colleagues, Alexander Silberman Institute of Life Sciences, Israel, investigated the molecular basis for this in honey bees. They reported at the IUSSI Russian congress that “some important features of the honey bee clock are more similar to mammals than to Drosophila (fruit flies),” and that “behavioral plasticity (variability) in circadian rhythms is mediated by molecular alternations…” The idea that organisms are regulated in their natural rhythm at the molecular level may come as a surprise to some, however, there is more and more evidence from various fields of study that much more happens at that level than previously recognized. Note the discussions concerning gene expression, sociality and swarming in previous articles on the IUSSI congress in this journal.

Regulating temperature can also be a function of the seasonal rhythm. Thermoregulation was the theme of one symposium at the St. Petersburg meeting. Honey bee colonies were studied by M. Kleinhenz, Beegroup Würzburg, and colleagues using heat sensitive thermography along with video and endoscopic recordings in observation hives. They found that many bees previously thought to be resting by observers were in fact “brood-heating specialists.” These workers placed their bodies in contact with the comb and had specific antennal and abdominal actions different than those found in resting bees. A definite “hot spot” could be seen when a brood-heating specialist bee that had previously been in contact with comb was removed from a specific location. In addition, the authors reported that heating specialists ensconced themselves in empty cells and could in this manner heat up to six adjacent cells containing brood. Similar behavior has been observed in paper wasps.

Julia Jones, University of Sydney, and colleagues described how learning and memory are affected by rearing temperatures. They reported that individuals with different patrilines (drone fathers) vary in thermoregulation, leading to the conclusion that “genetically diverse colonies are better able to maintain a stable brood temperature than genetically uniform colonies.” In addition, it appears that short-term memory is affected by temperature variation during pupal development, whereas long-term is not.

Alexander Komissar, National Agricultural University Ukraine, provided a description of his experiments wintering baby nuclei that had top-mounted electric heaters. These provided a small amount of heat that then developed into a "vertical temperature gradient" in the hives. Bees distributed themselves throughout the gradient from 15-36 degrees C. (59 – 96.8 F), in specific ways with most active movement above 25 degrees C (77 F). Queens preferred the zone above 26 degrees C (78.8 F). The heater-equipped nuclei over wintered successfully and two professional Ukrainian beekeepers use this method for mass storage of two-frame nucs in a temperate climate similar to northern USA or Canada (five months without a cleansing flight) with the aim of selling them in the spring. .

The tropics presents other challenges in terms of temperature extremes. Through an elaborate series of experiments, Yaacov Lensky, Emeritus Professor Triwaks Bee Laboratory, Rehovot, Israel reported on behavior of individual workers and colonies at high summer and low winter temperatures. Individual workers were resistant to as much as 50 degrees C (122 F), and continued foraging up to 48 degrees C (118.4 F). Evaporative cooling can reduce hive temperature, but it was concluded that keeping bees in white colonies was perhaps the best practical strategy. In addition, protecting colonies from winter cold either through use of black paint or Infrared-Polyethylene (PE)-covered enclosures was found to be effective. From these experiments, Dr. Lensky concluded: “Protection of bee colonies from extreme temperatures enhanced worker population size and production of spring and late summer honey yield, even in a mild Mediterranean-type subtropical climate.”

As would be expected, diseases and parasites got a good deal of play during the congress. There was a general session on these concerning both bumble bees and honey bees, with a special symposium on the latter insects, entitled: “Can European Honeybees Coexist With Varroa Mites?”

Mark Brown, Trinity College, Dublin, Ireland, reviewed current knowledge of host-parasite relations in a plenary or keynote lecture, which he said remains unclear in many areas. He concluded that high levels of redundancy in social insect colonies and patterns of division of labor act to reduce the apparent ecological cost of parasitism. A variety of examples of parasites were reported at the congress, including so-called “social parasites” that take advantage of interactions between members of a social host species. There is a bewildering array of these kinds of organisms and they run the gamut from being extremely to slightly detrimental. In addition, there are “inquilines” found in social insect nests that are considered benign, even beneficial. One hypothesis is that any parasite over time is embarked on a slow road to becoming (evolving) less damaging to its host, finally reaching a kind of equilibrium (mutualism) as an inquiline, where both host and now ex-parasite come to depend on each other for survival.

A symposium on social insects and their macroparasites provided some examples of social parasitism that while appearing to be unique have relevance to other social insect situations. A. Lenoir and colleagues University of Tours, France studied two kinds of ant queens, small (microgynes) and large (macrogynes), found in the same species (Manica rubida). Two hypotheses are put forth to explain why they differ: 1) small queens are social parasites involved in nest takeovers or 2) small queens establish nests in the region of the mother nest, whereas larger individuals fly long distances, providing two dispersal strategies. Carlos Lopez-Vaamonde and colleagues Zoological Society of London looked at bumble bee (Bombus terrestris) workers that invade unrelated colonies and produce male offspring in an effort to control a colony’s genetics. The same is true in slave-making ants studied by E. Brunner and colleagues, University Regensburg, Germany, who reported unrelated worker ants producing up to 100% of males in nests. Related to this is social parasitism found in honey bees when workers of Apis mellifera capensis invade colonies of Apis mellifera scutellata in Africa. Instead of producing males, however, invading workers (false queens) are able to produce workers, which then take over the nest. This has become a series problem in certain areas when scutellata colonies were moved into capensis territory or vice versa.

M. X. Ruiz-Gonzalez and colleagues, Trinity College, Dublin, Ireland tested the haploid susceptibility hypothesis. Males from unfertilized eggs (haploid) are thought to be more susceptible to diseases since they don’t have another set of alleles (genes) found in diploid individuals, which might confer resistance by masking the effects of a single damaging allele (gene). Infecting bumble bee (Bombus terrestris) colonies with a parasite (Crithidia bombi), however, revealed no difference in susceptibility between diploid workers and haploid males. That looks to be good news for those interested in bumble bee welfare in Europe who are concerned about social parasitism through production of males.

Another pathogen, Nosema bombi, is also being studied in Bombus terrestris, which can devastate bumble bee colonies used in greenhouse pollination. I. Fries and colleagues, Swedish University of Agricultural Science, Uppsala reported great variability in this organism in different bumble bee hosts. The rate of infection is also quite variable ranging from 1-3% in Sweden and Switzerland to about 13% elsewhere (Denmark, the Netherlands), according to Julia Klee, Queen’s University, Belfast, Ireland. Infection is horizontal (larva to larva), not vertical (egg to larva), according to J. van der Steen, Wageningen University, the Netherlands. Finally, O. Otti and colleagues ETH-Zurich, Switzerland tested the effects of infestation, finding infected colonies generally smaller and producing few if any sexual forms. They concluded that severe effects from Nosema bombi mean that it’s opportunity to affect the next host generation is minimal. Some of these findings may also apply to the relationship between Nosema apis, and its honey bee host.

Exotic organisms also affect social insects in many ways. Best known are those that have relatively recently been introduced to managed honey bee colonies, such as the small hive beetle (Aethina tumida) and the Asian mite, Varroa destructor. This author presented the most recent information on small hive beetle. Introduced in 1998 from Africa, this insect has greatly changed honey house management in the U.S. Its introduction shows in a very real way how transportation of organisms around the globe can affect great change in local ecosystems.

Of course nothing shows the effects of exotic organisms more than introduction of Varroa to Apis mellifera in the 1950s when, this mite transferred from its original host Apis cerana or indica. This has literally transformed apiculture on a worldwide basis and continues doing so to this day. In a symposium on whether Varroa can coexist with European bees, Adrian Wenner, University of California, Santa Barbara answered in the affirmative. His studies on populations isolated on offshore islands and in wilderness preserves show that wild or feral colonies (not treated by beekeepers) have survived Varroa depredations for a number of years, especially those with mixed genetics. The makes for what he calls the “exciting potential” of “survivor” colonies that are being increasingly studied around the world, including Dr. John Kefuss and colleagues who have incorporated Apis mellifera intermissa (the so-called “tell” bee in Tunisia) and the “Elgon” stock, a mixture of Buckfast and Apis mellifera monticola (mountain African), developed in Sweden.

Ingemar Fries, University of Agricultural Sciences, Upsalla reported on Swedish experiments, which amount to little more than isolating infested colonies on an island and monitoring survival and various other mite infestation parameters. Starting with 150 colonies, the results are that five original and five daughter colonies (swarms) are surviving six years later. During this interval there has been large variability across the spectrum of measurements. Thus, winter survival and swarming tendency both have increased and decreased over the period and mite infestation rate of colonies without brood decreased the fifth year of infestation. The experiment continues with the conclusion that “some sort of parasite adaptation has occurred, ensuring the survival of both host and parasite.”

P. Rosenkranz, University of Hohenheim, Stuttgart, Germany also reported on experiments looking at Varroa tolerance. Carniolan bees (Apis mellifera carnica) from Hohenheim (H) were compared with “survivor” colonies on the island of Gotland (G), left untreated since 1999 even after a dramatic mortality in 2002. In the year 2004, average initial infestations of 700 mites (G) and 400 (H) were calculated. The bee populations were 6,000 adult bees and 10,500 (G) and 14,000 (H) brood cells respectively. At the end of the season, G colonies had 16,500 while H decreased to 10,500 bees. Highest absolute infestations in August were 9,000 mites (H) and 6,500 (G). By the end of the year, all the H colonies had perished showing typical symptoms of heavy Varroa infestation. Only one G colony was lost due to queen problems, but the rest subsequently died during winter ending the experiment. Nevertheless, it is concluded that in spite of higher start infestation and higher brood mite counts throughout the season, it was clear that G colonies had significantly lower infestation rates at the end of the season. Thus, “preliminary results indicate that the G colonies have established mechanisms to reduce the increase of the Varroa population.”

This author provided information on the current status of “soft chemicals” in controlling Varroa in the U.S. and Canada. Topping the list are essential oils (tymol) and organic acids (formic, oxalic, lactic), the use of which was pioneered in Europe. There is little question that chemical treatment by beekeepers has kept Varroa in check, but the effective hard chemicals, fluvalinate (Apistan®), coumpahos (CheckMite+®) and amitraz, are now losing effectiveness as the mites continue to become resistant. There is less likelihood of this happening when beekeepers use hard pesticides in conjunction with soft chemicals and what are termed “biotechnical” controls (drone trapping, screened bottom boards). All this together is called integrated control or integrated pest management (IPM).

Specific and effective integrated control has been developed in the Netherlands. J.M. van der steen, Wageningen University, closed out the symposium by describing two regimens published in a standard Varroa control calendar, which do not incorporate hard chemicals. In the “default” situation (light mite infestation), drone trapping is recommended from April through June, followed by formic acid or thymol (Thymovar®) July through September. In the “emergency” scenario (heavy mite infestation), formic or lactic acid is recommended January and February, formic or thymol or drone trapping April and May (no treatment in March), followed by formic or thymol from June to September. Finally, October through December, the beekeeper returns to the January through February regimen.

Although not strictly a honey bee meeting, the 3^rd European Congress on Social Insects incorporated many studies on the biology of Apis mellifera and other social insects, the results of which could be of importance to both scientists and beekeepers. It is in this vein, that I have seen fit to report and the editor to print some of the highlights. This provides a small window into the study of social insects, perhaps encouraging some readers to attend 15^th International Congress of the International Union for the Study of Social Insects in Washington, DC, July 30 through August 5, 2006 <http://www.iussi.org/iussi2006.html>.