Jerzy Wilde

Miscellaneous standard methods for Apis mellifera research

Summary A variety of methods are used in honey bee research and differ depending on the level at which the research is conducted. On an individual level, the handling of individual honey bees, including the queen, larvae and pupae are required. There are different methods for the immobilising, killing and storing as well as determining individual weight of bees. The precise timing of developmental stages is also an important aspect of sampling individuals for experiments. In order to investigate and manipulate functional processes in honey bees, e.g. memory formation and retrieval and gene expression, microinjection is often used. A method that is used by both researchers and beekeepers is the marking of queens that serves not only to help to locate her during her life, but also enables the dating of queens. Creating multiple queen colonies allows the beekeeper to maintain spare queens, increase brood production or ask questions related to reproduction. On colony level, very useful techniques are the measurement of intra hive mortality using dead bee traps, weighing of full hives, collecting pollen and nectar, and digital monitoring of brood development via location recognition. At the population level, estimation of population density is essential to evaluate the health status and using beelines help to locate wild colonies. These methods, described in this paper, are especially valuable when investigating the effects of pesticide applications, environmental pollution and diseases on colony survival.

Standard methods for rearing and selection of Apis mellifera queens

Summary Here we cover a wide range of methods currently in use and recommended in modern queen rearing, selection and breeding. The recommendations are meant to equally serve as standards for both scientific and practical beekeeping purposes. The basic conditions and different management techniques for queen rearing are described, including recommendations for suitable technical equipment. As the success of breeding programmes strongly depends on the selective mating of queens, a subchapter is dedicated to the management and quality control of mating stations. Recommendations for the handling and quality control of queens complete the queen rearing section. The improvement of colony traits usually depends on a comparative testing of colonies. Standardized recommendations for the organization of performance tests and the measurement of the most common selection characters are presented. Statistical methods and data preconditions for the estimation of breeding values which integrate pedigree and performance data from as many colonies as possible are described as the most efficient selection method for large populations. Alternative breeding programmes for small populations or certain scientific questions are briefly mentioned, including also an overview of the young and fast developing field of molecular selection tools. Because the subject of queen rearing and selection is too large to be covered within this paper, plenty of references are given to facilitate comprehensive studies.

A review of methods for discrimination of honey bee populations as applied to European beekeeping

Summary Here, scientists from 19 European countries, most of them collaborating in Working Group 4: “Diversity and Vitality” of COST Action FA 0803 “Prevention of honey bee COlony LOSSes” (COLOSS), review the methodology applied in each country for discriminating between honey bee populations. Morphometric analyses (classical and geometric) and different molecular markers have been applied. Even if the approach has been similar, however, different methodologies regarding measurements, landmarks or molecular markers may have been used, as well as different statistical procedures. There is therefore the necessity to establish common methods in all countries in order to have results that can be directly compared. This is one of the goals of WG4 of the COLOSS project.

The influence of genetic origin and its interaction with environmental effects on the survival of Apis mellifera L. colonies in Europe

Summary The survival and performance of 597 honey bee colonies, representing five subspecies and 16 different genotypes, were comparatively studied in 20 apiaries across Europe. Started in October 2009, 15.7% of the colonies survived without any therapeutic treatment against diseases until spring 2012. The survival duration was strongly affected by environmental factors (apiary effects) and, to a lesser degree, by the genotypes and origin of queens. Varroa was identified as a main cause of losses (38.4%), followed by queen problems (16.9%) and Nosema infection (7.3%). On average, colonies with queens from local origin survived 83 days longer compared to non-local origins (p < 0.001). This result demonstrates strong genotype by environment interactions. Consequently, the conservation of bee diversity and the support of local breeding activities must be prioritised in order to prevent colony losses, to optimize a sustainable productivity and to enable a continuous adaptation to environmental changes.

Occurrence of parasites and pathogens in honey bee colonies used in a European genotype-environment interactions experiment

Summary Diseases are known to be one of the major contributors to colony losses. Within a Europe-wide experiment on genotype—environment interactions, an initial 621 colonies were set up and maintained from 2009 to 2012. The colonies were monitored to investigate the occurrence and levels of key pathogens. These included the mite Varroa destructor (mites per 10 g bees), Nosema spp. (spore loads and species determination), and viruses (presence/absence of acute bee paralysis virus (ABPV) and deformed wing virus (DWV)). Data from 2010 to the spring of 2011 are analysed in relation to the parameters: genotype, environment, and origin (local vs. non-local) of the colonies in the experiment. The relative importance of different pathogens as indicators of colony death within the experiment is compared. In addition, pathogen occurrence rates across the geographic locations are described.

Population dynamics of European honey bee genotypes under different environmental conditions

Summary Adaptation of honey bees to their environment is expressed by the annual development pattern of the colony, the balance with food sources and the host—parasite balance, all of which interact among each other with changes in the environment. In the present study, we analyse the development patterns over a period of two years in colonies belonging to 16 different genotypes and placed in areas grouped within six environmental clusters across Europe. The colonies were maintained with no chemical treatment against varroa mites. The aim of the study was to investigate the presence of genotype—environment interactions and their effects on colony development, which we use in this study as a measure of their vitality. We found that colonies placed in Southern Europe tend to have lower adult bee populations compared to colonies placed in colder conditions, while the brood population tends to be smaller in the North, thus reflecting the shorter longevity of bees in warmer climates and the shorter brood rearing period in the North. We found that both genotype and environment significantly affect colony development, and that specific adaptations exist, especially in terms of adult bee population and overwintering ability.

Apis mellifera mellifera in eastern Europe – morphometric variation and determination of its range limits

The variability of Apis mellifera mellifera in Eastern Europe was investigated with a morphometric analysis of 136 samples from Poland, Belarus and the Ukraine. Samples from the northern part of this area were unambiguously classified as A. m. mellifera, but the proportion of uncertain allocations increased towards the south, where some samples were classified as hybrids between A. m. mellifera and subspecies of the lineages C and O. In the Ukraine, one third of the samples were classified as A. m. mellifera, one third as A. m. macedonica, and one third as hybrids. Our results confirm earlier reports of a large hybrid zone in Poland and the Ukraine, but they unexpectedly also show a strong influence of the morphological O lineage. However, the true extension of this hybrid zone currently remains unknown. The bees of northeastern Belarus showed an extreme position on the border of the A. m. mellifera cluster, potentially indicating ecotypic variation within A. m. mellifera in the northeast of its range.ZusammenfassungDas Verbreitungsgebiet von Apis mellifera mellifera umfasst ganz Nordeuropa, von Frankreich im Westen, nach Skandinavien im Norden und Russland im Osten. Es reicht vermutlich bis zum Uralgebirge, wo seine Ostgrenze mit der Ostgrenze von Apis mellifera als Art zusammenfällt. Von früheren Publikationen über die morphometrische Variation von einzelnen Merkmalen in Russland abgesehen, ist sehr wenig über die Variabilität dieser Unterart in Osteuropa und ihre Beziehungen zu umgebenden Bienenpopulationen bekannt. In dieser Arbeit stellen wir die erste umfassende morphometrische Analyse von Populationen der Honigbiene in Osteuropa vor.Wir untersuchten die Variabilität von A. m. mellifera im Osten ihres Verbreitungsgebiets mit einer morphometrischen Analyse von 136 Proben, die in Nordost- und Südostpolen, sowie in Nordost- und Südost-Weißrussland und der Ukraine gesammelt wurden. In die Analyse wurden Referenzproben von umgebenden Unterarten einbezogen. In einer Diskriminanzanalyse (Abb. 2) wurden die Proben in drei Hauptgruppen angeordnet, die den geographischen Regionen Nord- und Westeuropa (Referenzproben von A. m. mellifera), Südosteuropa (A. m. carnica, A. m. ligustica and A. m. macedonica) und dem westlichen Asien (A. m. caucasica and A. m. anatoliaca) entsprachen. Bienen aus dem nördlichen Weißrussland nahmen eine extreme Position am Rand des A. m. mellifera Clusters ein, während Proben aus der Ukraine die drei Äste im Zentrum der Abbildung verbanden. Zu den anderen Gruppen (Nordost- und Südostpolen, Südost-Weißrussland) gehörende Proben erschienen zerstreut zwischen diesen Extremen. Proben aus Nordostpolen und Nordost-Weißrussland wurden eindeutig als A. m. mellifera klassifiziert, aber die Anzahl der unsicheren Zuordnungen nahm in Südostpolen und Südost-Weißrussland zu, wo einige Proben als Hybriden zwischen A. m. mellifera und A. m. carnica, A. m. macedonica, A. m. caucasica oder A. m. anatoliaca eingeordnet wurden. Die Zuordnung der Proben aus der Ukraine war noch mehr gemischt; hier wurde je ein Drittel der Proben als A. m. mellifera, A. m. macedonica und als Hybriden klassifiziert.Unsere Ergebnisse bestätigen damit ältere Berichte über eine ausgedehnte Hybridzone in Südpolen und der Ukraine, aber sie demonstrieren auch einen unerwarteten und starken Einfluss der morphologischen O-Linie im südlichen Teil des Sammelgebiets. Der Charakter und die tatsächliche Ausdehnung dieser Hybridzone ist jedoch unbekannt, da keine Daten aus Regionen östlich und südlich unseres Sammelgebiets vorhanden sind. In allen Analysen nahmen die Bienen aus Nordost-Weißrussland extreme Positionen am Rand des A. m. mellifera Clusters ein. Möglicherweise ist dies ein Hinweise auf ökotypische Variation von A. m. mellifera im nordöstlichen Teil ihres Verbreitungsgebiets.

Swarming and Migration of Apis dorsata and Apis laboriosa Honey Bees in India, Nepal and Bhutan

Swarming and Migration of Apis dorsata and Apis laboriosa Honey Bees in India, Nepal and Bhutan The migratory open air nesting Apis dorsata and Apis laboriosa honeybees migrate at least twice a year. DNA genotyping showed that the same swarms return to their natal nesting sites. We examined 23 nesting sites in Nepal, India and Bhutan, on which 587 colonies of A. dorsata and A. laboriosa nested. The results showed that the frequency of the periodic mass flights (PMF) performed by the colonies is a good indicator of the status of current colony performance. During the swarming period, both, A. dorsata and A. laboriosa issue several swarms. In some colonies, so many bees swarmed out, that those remaining in the maternal colonies did not cover the combs. After the rest of the brood emerged, all the bees of such colonies abscond during the swarming period. Thus, absconding appeared in results of total out swarming. The swarms do not migrate directly to the seasonal alternative nesting sites, but establish new colonies in the areas around. After environmental conditions deteriorate, all the bees with their queens abscond and migrate to alternate seasonal nesting sites. The next season, the swarms do not return to their original reproductive natal sites, but to those sites they occupied the previous season lately, where from they absconded. Rójka i Wędrówka Pszczół Apis Dorsata i Apis Laboriosa w Indiach, Nepalu i Bhutanie Wolno gniazdujące azjatyckie pszczoły Apis dorsata i Apis laboriosa wędrują co najmniej dwa razy w roku. Genotypowe badania DNA wykazały, że roje wracają do swych macierzystych miejsc gniazdowania. Zbadaliśmy 23 miejsc gniazdowania w Nepalu, Indiach i Bhutanie, na których gniazdowało 587 rodzin A. dorsata i A. laboriosa. Stwierdziliśmy, że okresowe masowe loty (ang. skrót PMF) wykonywane przez te pszczoły, są dobrym wskaźnikiem stanu rodzin pszczelich. Zaobserwowaliśmy, że w okresie rójki, kilka rojów wyrajało się z macierzaków A. dorsata i A. laboriosa. Z niektórych macierzaków wyrajało się tak wiele pszczół, że pozostałe nie pokrywały plastrów. Po wygryzieniu się robotnic z resztek czerwiu, wszystkie pszczoły z takich rodzin opuszczały plastry w okresie rójki. Tak więc u badanych pszczół, zdarza się, że wszystkie pszczoły opuszczają plastry, na skutek rójki. Zjawisko takie nie zachodzi u gniazdujących w pomieszczeniach pszczół A. mellifera. Roje Apis dorsata i Apis laboriosa nie wędrują bezpośrednio do sezonowych alternatywny miejsc gniazdowania, lecz osiedlają się w innych miejscach w okolicy, budują tam plastry i tworzą nowe rodziny. Rójka i tworzenie nowych gniazd zrywa poczucie jedności z macierzakami. Po pogorszeniu się warunków środowiskowych i braku źródeł pokarmu wszystkie pszczoły porzucają plastry i wędrują (migrują) do alternatywnych sezonowych miejsc gniazdowania. Gdy tam warunki środowiskowe i żywnościowe pogorszą się, pszczoły porzucają tam plastry i wędrujące roje wracają. Jednak ubiegłoroczne nowe roje nie powracają do miejsc gniazdowania macierzaków, lecz do swoich miejsc gniazdowania, z których wyemigrowały w ubiegłym sezonie.

A review of methods used in some European countries for assessing the quality of honey bee queens through their physical characters and the performance of their colonies

Summary The term “quality” in relation to queens and drones refers to certain quantitative physical and/or behavioural characters. It is generally believed that a high quality queen should have the following physical characteristics: high live weight; high number of ovarioles; large size of spermatheca; high number of spermatozoa in spermatheca; and be free from diseases and pests. It is, however, also known that the performance of a honey bee colony is the result of its queens function as well as of that of the drones that mated with her. These two approaches are often considered together and give a general picture of the queen production technique and selection. Here we describe the most common and well known anatomical, physiological, behavioural and performance characters related to the queens, as measured in different European countries: the live weight of the virgin queen (Bulgaria); the live weight of the laying queen (Bulgaria, Italy); the diameter and volume of spermatheca (Bulgaria, Greece, Slovenia); the number of ovarioles (Greece, Italy, Slovenia); the weight of ovaries (Slovenia); the number of spermatozoa in spermatheca (Italy, Poland, Slovenia); the brood pattern (Bulgaria, Greece); the egg laying ability/fecundity (Bulgaria); the brood production (Croatia, Serbia); the colony population development (Croatia, Serbia, Slovakia); the honey production (Croatia, Denmark, Serbia, Slovakia); the hygienic behaviour (Croatia, Denmark, Serbia, Slovakia); the defence behaviour (Croatia); the calmness/sitting on the comb (Croatia, Denmark); and swarming (Croatia, Denmark). The data presented fit well with the findings of the same characters in the literature, and in general they support the argument for the term “quality characters”. Especially for the weight of the queen, the number of ovarioles, the volume of the spermatheca and the number of spermatozoa, data per country proved its own accuracy by repetition through the years. We also report that when instrumentally inseminated queens are kept under mass production conditions (in small cages in queen banks and with low number of attendants) they can transfer the semen to their spermatheca and clear their oviducts more efficiently when they have been inseminated with small amounts of semen in two or three sequences (but not four), compared to those inseminated with the same amount of semen at once (Poland). Furthermore, we had an inside view of the sanitary conditions of the colony: a. through the health status of the queen (nosema plus virus analysis) (Slovenia); and b. evaluating the nosema load of worker bees (Denmark) and of the queens (Greece). This is the first step to summarize this type of diverse data for such an important issue. The knowledge acquired can be used to fill in the existing gaps in the breeding or queen evaluation systems of each country in order to facilitate standardization of methodology for comparable results.

Swarming, defensive and hygienic behaviour in honey bee colonies of different genetic origin in a pan-European experiment

Summary Honey bee colonies exhibit a wide range of variation in their behaviour, depending on their genetic origin and environmental factors. The COLOSS Genotype-Environment Interactions Experiment gave us the opportunity to investigate the phenotypic expression of the swarming, defensive and hygienic behaviour of 16 genotypes from five different honey bee subspecies in various environmental conditions. In 2010 and 2011, a total of 621 colonies were monitored and tested according to a standard protocol for estimation of expression of these three behavioural traits. The factors: year, genotype, location, origin (local vs. non-local) and season (only for hygienic behaviour) were considered in statistical analyses to estimate their effect on expression of these behaviours. The general outcome of our study is that genotype and location have a significant effect on the analysed traits. For all characters, the variability among locations was higher than the variability among genotypes. We also detected significant variability between the genotypes from different subspecies, generally confirming their known characteristics, although great variability within subspecies was noticed. Defensive and swarming behaviour were each positively correlated across the two years, confirming genetic control of these characters. Defensive behaviour was lower in colonies of local origin, and was negatively correlated with hygienic behaviour. Hygienic behaviour was strongly influenced by the season in which the test was performed. The results from our study demonstrate that there is great behavioural variation among different subspecies and strains. Sustainable protection of local genotypes can be promoted by combining conservation efforts with selection and breeding to improve the appreciation by beekeepers of native stock.