Reproduction of Varroa destructor in worker brood of Africanized honey bees (Apis mellifera)

Reproduction and population growth of Varroa destructor was studied in ten naturally infested, Africanized honeybee (AHB) (Apis mellifera) colonies in Yucatan, Mexico. Between February 1997 and January 1998 monthly records of the amount of pollen, honey, sealed worker and drone brood were recorded. In addition, mite infestation levels of adult bees and worker brood and the fecundity of the mites reproducing in worker cells were determined. The mean number of sealed worker brood cells (10,070 ± 1,790) remained fairly constant over the experimental period in each colony. However, the presence and amount of sealed drone brood was very variable. One colony had drone brood for 10 months and another for only 1 month. Both the mean infestation level of worker brood (18.1 ± 8.4%) and adult bees (3.5 ± 1.3%) remained fairly constant over the study period and did not increase rapidly as is normally observed in European honey bees. In fact, the estimated mean number of mites fell from 3,500 in February 1997 to 2,380 in January 1998. In May 2000 the mean mite population in the study colonies was still only 1,821 mites. The fertility level of mites in this study was much higher (83–96%) than in AHB in Brazil(25–57%), and similar to that found in EHB (76–94%). Mite fertility remained high throughout the entire study and was not influenced by the amount of pollen, honey or worker brood in the colonies. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Impact of Recent Queenloss and Colony Pheno-type on the Removal of Small Hive Beetle (Aethina tumida Murray) Eggs and Larvae by African Honeybee Colonies (Apis mellifera capensis Esch.)

The removal of small hive beetle [=SHB] eggs and larvae was studied in queenright and recently queenless Cape honeybee, Apis mellifera capensis, colonies over a range of phenotypes. The overall removal efficiency was not influenced by phenotypes or queenstate, because all introduced eggs and larvae were removed within 24 hours. Queenless colonies removed them merely slower than queenright ones. The latter ones rejected up to 300 larvae within one hour. However, colonies undergoing preparation for absconding did not completely remove SHB offspring, suggesting that removal efficiency was reduced. Since even small and recently queenless colonies effectively removed immature SHB, and no differences in the overall efficiency was found compared to A. m. scutellata we conclude that this defense behavior is well developed in African honeybees.     

The provision of supplementary food to hive bees

Sucrose syrup is less satisfactory than honey as a winter and spring food for bees: a mixture of approximately equal parts of honey and syrup is of almost the same value as honey alone.
Feeding confined to early autumn induced the strongest spring development of colonies; syrup feeding in the spring may retard colony development, and food supplied at this time is apparently wasted. Feeding with syrup and pollen is advantageous only when a colony is lacking in stores of carbohydrate and protein.
A total of four British Standard brood combs full of pollen provides sufficient protein for a colony on B.S. equipment from autumn until April: the best results were obtained by providing colonies on eleven B.S. combs, in early autumn, with 35-40 lb. of honey, or honey and concentrated sucrose syrup, and four brood combs full of pollen.     

Net reproductive rate of unmanaged honeybee colonies, (Apis mellifera L.)

Summary The net reproductive rate of unmanaged honeybee colonies has never been fully determined for honey bees in temperate climates. In this study, five overwintered colonies in Kansas, USA, were allowed to swarm naturally (Winston. 1980). These colonies and their swarms were studied over the winter (i.e. one generation). The net reproductive rateR ₀ was estimated to be 2.18. Afterswarms were found to contribute substantially (41.2%) to this net reproductive rate. The autumn and spring food reserves and brood areas of established colonies and colonies established from prime swarms and afterswarms are compared. Winter survival of afterswarms was related to autumn honey stores, and the brood areas of surviving afterswarms were smaller than those of prime swarms or established colonies.     

Social parasitism by Cape honeybee workers in colonies of their own subspecies (Apis mellifera capensis Esch.)

Social parasitism is widespread in the eusocial insects. Although social parasites often show a reduced worker caste, unmated workers can also parasitize colonies. Cape honeybee workers, Apis mellifera capensis, can establish themselves as social parasites in host colonies of other honeybee subspecies. However, it is unknown whether social parasitism by laying workers also occurs among Cape honeybee colonies. In order to address this question we genotyped worker offspring of six queenless A. m. capensis colonies and determined the maternity of the reproducing workers. We found that three non-nestmate workers dominated reproduction in a host colony and produced 62.5% of the progeny. Our results show that social parasitism by laying workers is a naturally occurring part of the biology of Cape honeybees. However, such social parasitism is not frequently found (6.41% of the total worker offspring) probably due to co-evolutionary processes among A. m. capensis resulting in an equilibrium between selection for reproductive dominance in workers, colony maintenance and queen adaptation. Received 28 July 2005; revised 19 September and 11 November 2005; accepted 16 November 2005.     

Confinement Behavior of Cape Honey Bees (Apis mellifera capensis Esch.) in Relation to Population Densities of Small Hive Beetles (Aethina tumida Murray)

We quantified the effects of increasing small hive beetle (Aethina tumida Murray) populations on guarding behavior of Cape honey bees (Apis mellifera capensis, an African subspecies). We found more confinement sites (prisons) at the higher (50 beetles per colony) rather than lower (25 beetles per colony) beetle density. The number of beetles per prison did not change with beetle density. There were more guard bees per beetle during evening than morning. Neither guard bee nor beetle behavior varied with beetle density or over time. Forty-six percent of all beetles were found among the combs at the low beetle density and this increased to 58% at the higher one. In neither instance were beetles causing depredation to host colonies. Within the limits of the experiment, guarding behavior of Cape honey bees is relatively unaffected by increasing beetle density (even if significant proportions of beetles reach the combs).     

The effects of land use on honey bee (Apis mellifera) population density and colony strength parameters in the Eastern Cape, South Africa

Livestock farming in the Eastern Cape, South Africa is a common land use practice that has affected the biodiversity of plants and animals in the region negatively. Indigenous populations of wild honey bee (Apis mellifera) colonies also may suffer. Recently, farmers in the Eastern Cape have been converting their farms to game reserves as ecotourism attractions and nature conservation lands. Consequently, the goal of this research was to determine if land use habits (livestock farming and conversion to game reserves) in the Eastern Cape affect honey bee colony population density and colony strength parameters. A series of indices were developed to compare the relative population densities of colonies in two or more areas by counting the number of foraging bees and number of bee lines established at feeding stations. Wild colonies on farms and reserves were located and sampled to determine land use effects on colony strength parameters including total area of comb in the colony, the area of comb containing stored honey, pollen, and brood, adult bee population, weight per bee, and the colony nest cavity volume ratio. When viewed collectively, the data indicated that land use practices have affected honey bee nesting dynamics in the Eastern Cape. Trends in the data suggested that colonies nesting on the reserves may occur in greater densities than those nesting on livestock farms, though they do not appear to be healthier. Hopefully, this work will be continued since honey bee conservation in areas where they are native is crucial to the health of agriculture and whole ecosystems globally.     

The relationship between comb age and performance of honey bee (Apis mellifera) colonies

A study on the relationship between the age of comb and the activity of the hybrid Carniolan honey bee colonies in collecting pollen activity, worker brood production, colony strength, and honey yield was conducted. In comparison to colonies with combs aged 4-years, colonies with combs aged 1, 2 and 3-years significantly exceeded in the number returning workers, number returning workers with pollen loads, rate of storing pollen, rate of worker brood production, and size of colony population. Colonies with combs aged 1, 2 and 3-years produced significantly more honey than colonies with combs aged 4-years (5.25, 4.90 and 4.65 kg/colony vs. 4.45 kg/colony, respectively). It can be concluded that the foraging rate, gathering and storing pollen, brood production, colony population size, and honey yield significantly depended on the age of combs. Beekeepers can replace old combs with new ones to increase brood and honey production.     

Honey bee (<Emphasis Type="Italic">Apis mellifera capensis/A. m. scutellata</Emphasis> hybrid) nesting behavior in the Eastern Cape,South Africa

Little is known about the natural history of wild honey bee (Apis mellifera) colonies in the Eastern Cape Province of South Africa. The goal of this research was to examine nest site characteristics of honey bee (A. m. capensis/A. m. scutellata hybrid) colonies sampled from a variety of habitats (nature reserves, livestock farms, and an urban setting) in the Eastern Cape. We also determined how nest site location related to various colony strength parameters. In general, colonies not nesting in ground cavities tended to nest in locations >6 m high when nesting in cliffs and buildings and >2 m high when nesting in trees. Colonies typically nested in cavities whose entrances faced a southeasterly direction and were ~40 L in volume. We sampled a subset of colonies to determine the relationship between nest type and the following colony strength parameters: total area of comb in the colony, the volume of stored honey, pollen, and brood, adult bee population, the weight per adult bee, and the bee/nest cavity volume ratio. In general, colonies nesting in cliffs tended to be stronger than those nesting in the ground or trees. Our findings provide new insights into the nesting biology of honey bees in the Eastern Cape, South Africa, perhaps leading to the formation of conservation recommendations for honey bees in this region.     

Factors influencing seasonal absconding in colonies of the African honey bee,Apis mellifera scutellata

Summary This study investigated the effects of colony growth and development, food storage, foraging activity and weather on the migration behavior of African honey bees in the Okavango River Delta, Botswana. Four observation colonies were studied during the honey bee migration season (November–May), at which time the availability of blooming species was reduced. Two of the colonies (colonies 1 & 2) migrated during the study period, while the remaining two (colonies 3 & 4) did not. During the 4–6 weeks preceding the onset of migration preparations, colonies 1 & 2 exhibited increasing population sizes, high levels of brood production with low brood mortality, relatively large stores of food, and increasing mass. In contrast, the populations of colonies 3 & 4 did not increase, brood-rearing activity was erratic and lower, brood mortality was higher, food stores became depleted and colony mass declined. Both colonies 3 & 4 ceased rearing brood, and colony 3 died of starvation. Colony foraging activity was examined by monitoring waggle-dance activity 2–3 days each week. For 4–6 weeks before the onset of migration in colonies 1 & 2, daily foraging areas and mean daily foraging distances became increasingly large and variable. Colonies 3 & 4 exhibited foraging patterns similar to those observed for colonies 1 & 2 preceding migration. There was no clear association between 7 weather parameters examined and migration behavior. These data suggest that migration is influenced by an interaction of intra-colony demographics, food reserves and foraging patterns. Migration may be feasible only for those colonies that possess (1) a population of appropriate size and age structure to compensate for the natural attrition of older workers during the emigration process, and (2) sufficient food reserves for long-distance travel and the establishment of a new nest. Changing foraging patterns may reflect a deteriorating foraging environment, which may trigger the onset of migration preparations, provided that colony demographics and food reserves are conducive. Colonies that show decreased brood production, higher brood mortality and reduced food stores may be incapable of migrating, even when experiencing deteriorating foraging conditions. Rather, such colonies may have a greater chance of survival if they attempt to persist in a given area.     

Comparison of the activity and productivity of Carniolan (Apis mellifera carnica Pollmann) and Yemeni (Apis mellifera jemenitica Ruttner) subspecies under environmental conditions of the Al-Ahsa oasis of eastern Saudi Arabia

This study was conducted at the apiary of the Agricultural and Veterinary Training and Research Station of King Faisal University in the Al-Ahsa oasis of eastern Saudi Arabia. We performed a comparison between Carniolan (Apis mellifera carnica Pollmann) and Yemeni (Apis mellifera jemenitica Ruttner) honeybee races to determine the monthly fluctuations in foraging activity, pollen collection, colony growth and honey yield production under the environmental conditions of the Al-Ahsa oasis of eastern Saudi Arabia. We found three peaks in the flight activity of the two races, and the largest peaks occurred during September and October. Compared to Carniolan bee colonies, the performance of Yemeni bee colonies was superior in terms of stored pollen, worker and drone brood rearing, and the adult population size. The Carniolan bee colonies produced 27.77% and 27.50% more honey than the Yemeni bee colonies during the flow seasons of alfalfa and sidir, respectively, with an average increase of 27.64%. It could be concluded that the race of bees is an important factor affecting the activity and productivity of honeybee colonies. The Yemeni bee race produced more pollen, a larger brood and more bees, which exhibited a longer survival. The imported Carniolan bees can be reared in eastern Saudi Arabia, but the Yemeni bee race is still better.     

The relationship between population size,amount of brood,and individual foraging behaviour in the honey bee,Apis mellifera L.

This study experimentally examines the relationship between colony state and the behaviour of individual pollen and nectar foragers in the honey bee, Apis mellifera L. In the first experiment we test the prediction that individual pollen foragers from colonies with higher brood quantities should exhibit a greater work effort for pollen resources than individual pollen foragers from colonies with low brood quantities. Eight colonies were assigned into two treatment groups; HIGH brood colonies were manipulated to contain 9600±480 cm² brood area; LOW brood colonies were manipulated to contain 1600±80 cm² brood area. We measured colony brood levels over the course of the experiment and collected individual pollen loads from returning pollen foragers. We found that, while colonies remained significantly different in brood levels, individual pollen foragers from HIGH brood colonies collected larger loads than individuals from LOW brood colonies. In the second experiment we investigated the influence of colony size on the behaviour of individual nectar foragers. We assigned eight colonies to two treatment groups; LARGE colonies were manipulated to contain 35000±1700 adult workers with 3500±175 cm² brood area, and SMALL colonies were manipulated to contain 10000±500 adult workers with 1000±50 cm² brood area. We observed foraging trips of individually marked workers and found that individuals from LARGE colonies made longer foraging trips than those from SMALL colonies (LARGE: 1666.7±126.4 seconds, SMALL: 1210.8±157.6 seconds), and collected larter nectar loads (LARGE: 19.2±1.0 l, SMALL: 14.6±0.8 l). These results indicate that individual nectar foragers from LARGE colonies tend to work harder than individuals from SMALL colonies. Both experiments indicate that the values of nectar and pollen resources to a colony change depend on colony state, and that individual foragers modify their behaviour accordingly.     

Nest characteristics and recruitment behavior of absconding colonies of the African honey bee,Apis mellifera scutellata,in Africa

Absconding behavior was investigated in a naturally occurring population of honey bees in the Okavango River Delta, Botswana. Fifty percent of all colonies excavated in the field between October and December had abandoned the nest or were preparing for absconding, suggesting that an absconding season began in the Delta in October or November. However, the factors influencing absconding during this period were unclear, and there were no distinct differences in nest characteristics of the absconding and nonabsconding colonies. Waggle dance activity in observation colonies preparing for absconding was not used to preselect a specific nest site prior to departure. However, in two of the three colonies examined recruitment activity indicated the general direction of colony travel. The distances indicated by these dancers ranged between 6 and 16 km. Since these distances were three to four times greater than those communicated by dancers in nonabsconding colonies, workers from absconding colonies may sample potential forage or nest sites well outside their regular foraging range.     

Performance of honeybee colonies located in neonicotinoid‐treated and untreated cornfields in Quebec

Twenty‐two honeybee (Apis mellifera) colonies were placed in four different cornfield areas in order to study the potential in situ effects of seed‐coated systemic neonicotinoid pesticides used in cornfields (Zea mays spp) on honeybee health. Two apiaries were located in two independent neonicotinoid‐treated cornfield areas and two others in two independent untreated cornfield areas used as controls. These experimental hives were extensively monitored for their performance and health traits over a period of one year. Trapped pollen was collected and microscopically identified to define the visited flowers and the amount of corn pollen collected by bees. Liquid chromatography–mass spectrometry was performed to detect pesticide residues in honeybee foragers and trapped pollen. Honeybee colonies located in neonicotinoid‐treated cornfields expressed significantly higher varroa mite loads than those in untreated cornfields. However, brood production and colony weight were less disturbed by the treatment factor. Sublethal doses of neonicotinoids were detected in the trapped corn pollen and none in bee foragers. Overall, our results show that forager bees collected 20% of corn pollen containing variable concentrations of neonicotinoids. Colonies located in treated cornfields expressed higher varroa loads and long‐term mortality than those in untreated cornfields. On the other hand, no significant differences were observed regarding the brood production and colony weight.     

Regulation of nectar collection in relation to honey storage levels by honey bees, Apis mellifera

Honey bees collect distinct nutrient sources in the form ofnectar (energy) and pollen (nitrogen). We investigated the effectof varying energy stores on nectar and pollen foraging. We foundno significant changes in nectar foraging in response to changesin honey storage levels within colonies. Individual foragersdid not vary activity rates or nectar load sizes in responseto changes in honey stores, and colonies did not increase nectarintake rates when honey stores within the hive were decreased.This result contrasts with pollen foraging behavior, which isextremely sensitive to colony state. Our data show that individualforaging decisions during nectar collection and colony regulationof nectar intake are distincdy different from pollen foraging.The behavior of honey bees illustrates that foraging strategy(and therefore foraging models) can incorporate multiple currencies,including both energy and protein intake.[Behav Ecol 7: 286–291(1996)]     

Spatial foraging patterns and colony energy status in the African honey bee,Apis mellifera scutellata

The relationship between changes in foraging patterns (inferred from waggle dance activity) and colony energy status (inferred from brood rearing activity, food storage, and colony weight) was examined for the African honey bee during a period of relative resource abundance and resource dearth. When resources were more abundant mean foraging distances (about 400 m) and foraging areas (4–5 km²) were small, and colonies recruited to 12–19 different sites per day. Colony foraging ranges and sites visited increased slightly during the dearth period, yet foraging continued to be concentrated within less than 10 km². The degree to which fluctuations in foraging patterns were correlated with colony energy status varied with the availability of floral resources. During periods of relative forage abundance, increases in foraging range and number of sites visited were significantly correlated with increases in brood rearing and colony weight. In contrast, colonies examined during periods of resource dearth exhibited no correlations between foraging areas, foraging distances, and fluctuations in brood rearing, food storage, or colony weight. Thus, during dearth periods colonies may not be able to coordinate foraging patterns with changes in colony energy status.     

THE INFLUENCE OF STORED POLLEN AND OF COLONY SIZE ON THE BROOD REARING OF HONEYBEES

Four hundred and thirty records of the numbers of bees in honeybee colonies and of the amounts of brood and pollen present have been kept during various months of the years 1945-53, and the data have been used to calculate total and partial regression coefficients showing the influence of stored pollen and of colony size on brood rearing throughout the year.
It was found that pollen storage and colony size were correlated but that, even allowing for this, colony size and pollen both independently influenced brood rearing.
The annual distribution of the total regression coefficients of brood on pollen was somewhat similar to the brood curve itself, rising from a minimum in October and November to a maximum in midsummer, while the partial regression coefficients showed less clearly marked but similar features.
Both total and partial regression coefficients showing the influence of colony size on the amount of brood reared were also at a minimum in October and November, but reached their peaks in May.
The quantities of brood present in these colonies at Aberdeen, Scotland, followed a pattern similar to that given by Nolan for colonies near Washington, D.C.     

Seasonal cycles of growth,development and movement of the African honey bee,Apis mellifera scutettata,in Africa

Summary The relationship between the annual colony cycle and seasonal patterns of forage availability was investigated for the African honey bee,Apis mellifera scutellata, in the Okavango River Delta, Botswana. The annual cycle occurred in three distinct periods. The swarming season occurred from October-November, following two to three months of intense brood production, and coincided with the end of peak forage abundance. The migration season occurred from November-May and coincided with reduced and variable floral resources. During the migration season, brood production and food storage were generally low but quite variable from month to month, and swarms passing over the study area at this time traveled in an easterly direction. The migration season was followed by the establishment period (June-September), in which large numbers of new colonies traveling from the west moved into the study area. The establishment period coincided with, and slightly preceded, the period of peak forage abundance, and colonies devoted resources collected at this time almost entirely to brood rearing, which culminated in swarm production. The data suggest that honey bee colonies in the Okavango are mobile and gear their reproduction and movement to seasonally shifting resource pattern.     

澜沧江流域北部中华蜜蜂有毒蜂蜜孢粉学和营养生态位分析

为分析澜沧江流域北部人食用蜂蜜中毒的原因,于2013年6—9月份,对该区域蜜蜂和蜜源植物的分布情况进行了调查,观察蜜蜂采集有毒蜜源植物的行为,并进一步调查了蜜蜂巢内蜂蜜、蜂花粉的储存情况,采集了中华蜜蜂蜂蜜样品,进行蜂蜜孢粉学与营养生态位分析。该区域有大量采用传统方式进行人工饲养的中华蜜蜂(Apis cerana cerana),及少量野生中华蜜蜂、黑色小蜜蜂(Apis audreniformis)、黑色大蜜蜂(Apis laboriosa smith)群体分布;人工饲养的中华蜜蜂蜂巢内部结构与野生中华蜜蜂蜂巢相似,为自然蜂巢,内有充足的蜜粉储存,部分蜂群蜂巢内虫害严重。该区域内主要蜜源植物为荞麦(Fagopyrum esculentum Moench),其他零星辅助蜜源较多,部分地点南烛(Vaccinium bracteatum Thunb)、昆明山海棠(Tripterygium hypoglaucum(Levl.)Hutch)连片集中分布。对中华蜜蜂蜂蜜进行孢粉学和营养生态位分析,结果表明:中华蜜蜂蜂蜜标本中含有有毒蜜源植物南烛、昆明山海棠花粉,部分样品中南烛、昆明山海棠的花粉含所占比例较高;中华蜜蜂的营养生态位宽度为0.22,比其他地区中华蜜蜂生态位指数小,推测澜沧江水电枢纽的修建等人为原因已对蜜蜂种类、蜜源植物的物种组成、群落结构造成了较大影响。     

Effects of brood pheromone (SuperBoost) on consumption of protein supplement and growth of honey bee (Hymenoptera: Apidae) colonies during fall in a northern temperate climate

Honey bee, Apis mellifera L. (Hymenoptera: Apidae), nutrition is vital for colony growth and maintenance of a robust immune system. Brood rearing in honey bee colonies is highly dependent on protein availability. Beekeepers in general provide protein supplement to colonies during periods of pollen dearth. Honey bee brood pheromone is a blend of methyl and ethyl fatty acid esters extractable from cuticle of honey bee larvae that communicates the presence of larvae in a colony. Honey bee brood pheromone has been shown to increase protein supplement consumption and growth of honey bee colonies in a subtropical winter climate. Here, we tested the hypothesis that synthetic brood pheromone (SuperBoost) has the potential to increase protein supplement consumption during fall in a temperate climate and thus increase colony growth. The experiments were conducted in two locations in Oregon during September and October 2009. In both the experiments, colonies receiving brood pheromone treatment consumed significantly higher protein supplement and had greater brood area and adult bees than controls. Results from this study suggest that synthetic brood pheromone may be used to stimulate honey bee colony growth by stimulating protein supplement consumption during fall in a northern temperate climate, when majority of the beekeepers feed protein supplement to their colonies.