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Bee-eaters (Meropidae) are considered agricultural pests and their presence provokes conflicts with beekeepers and farmers who rely on the pollination services of honey bees. This problem is often deal with through the mass killing of the birds, even though the quantitative evidence on the impact of bee-eaters on honey bee colonies is scarce. The current paper reports the performance of honey bee colonies protected with mist nets from migrating flocks of European bee-eaters Merops apiaster in Israel. In the study the weight gains of bee hives surrounded by mist nets were 6.44 times higher than that of unprotected hives (26.4 kg vs. 4.1 kg). The results confirmed that bee-eaters locally pose a problem to apiaries and potentially to the crops that require pollination. Mist- netting appeared to be an effective mitigation method for alleviating conflicts between beekeepers and bee-eaters. However, the study also showed that bees were able to differentiate between their main predator and other avian species trapped in mist nets and stung only bee-eaters. Moreover, the bees were targeting the most vulnerable body parts of birds which resulted in some bird fatalities. Therefore, due to accidental mortal- ity of birds, mist-netting is recommended only on the migratory routes in cases when bee hives cannot be moved to other areas.

The aim of the current study was to determine the floral phenology, nectar secretion dynamics, and honey production potentials of two naturally growing lavender species (L. dentata and L. pubescens), in southwestern Saudi Arabia. In both species, flowering is continuous. This means that, when open flowers on a spike are shaded, new flowers emerge. Such a flowering pattern might be advantageous to the plant to minimise competition for pollinators and promote efficient resource allocation. The flowering periods of the two species overlap. Both species secreted increasing amounts of nectar from early morning to late afternoon. The mean maximum volumes of accumulated nectar from bagged flowers occurred at 15:00 for L. pubescens (0.50 ± 0.24 μL/flower) and at 18:00 for L. dentata (0.68 ± 0.19 μL/flower). The volume of the nectar that became available between two successive measurements (three-h intervals) varied from 0.04 μL/flower to 0.28 μL/flower for L. pubescens and from 0.04 μL/flower to 0.35 μL/ flower for L. dentata, This variation reflects the differences in the dynamics of nectar secretion by these species, and indicates the size of the nectar that may be available for flower visitors at given time intervals. The distribution of nectar secretions appears to be an adaptation of the species to reward pollinators for longer duration. Based on the mean amount of nectar sugar secreted by the plants, the honey production potentials of the species are estimated to be 4973.34 mg and 3463.41 mg honey/plant for L. dentata and L. pubescens, respectively.

The aim of the study was to determine the effect of honey bee worker diversity within the colony on: development, honey productivity, and wintering. Two different levels of diversity within the colony were tested. The appropriate levels of diversity within the colony were obtained by selecting drones for inseminating the queens. Lower genetic diversity was obtained in the colonies headed by a queen inseminated with semen collected from drones originating from a single colony. Higher genetic diversity was obtained in the colonies with queens inseminated with semen from drones of 30 different colonies. Colonies with a higher genetic variation of workers in the colonies had greater levels of functional characteristics. However, apart from the number of dead bees in winter, the genetic diversity level of the workers on the colony development and honey production, did not have a significant influence. There was an averaging effect observed concerning that male component in the colonies with a higher genetic variation of workers - on honey yield, when compared to the non-additive effect of the best drones.

The performance of bee colonies greatly depends on the quality of the queens. The current research was conducted at the apiary of the Faculty of Agriculture, Zanjan University, in Zanjan, Iran. Together, 24 rearing colonies were assigned to 4 grafting larvae age groups: 1-day-old, 2-day-old, 3-day-old, and emergency queens. Two feeding groups, fed and not fed, were created. The effects of reared queens on biological characteristics and performance of honeybee colonies (Apis mellifera meda) headed by those queens were measured. Age of grafted larvae significantly influenced the results. The performance ratios of the most efficient colonies headed by queens reared from 1-day-old larvae compared with the least-efficient queens reared from 3-day-old larvae were 118% in brood production, 140% in bee population, and 154% in honey production. However, the age of grafted larvae did not affect colony defense behavior. Supplemental feeding of rearing colonies increased brood production to 111%, bee population to 116%, and honey production to 115%. A combination of the effect of age of larvae and supplemental feeding resulted in twice as much honey (12 kg) produced by colonies with queens reared from 1-day-old larvae in fed rearing colonies compared to those with queens raised from 3-day-old larvae in unfed rearing colonies.

The nectar secretion of Ziziphus flowers was studied by removing and measuring the nectar every four hours, for two consecutive days, from 88 flowers of four trees (‘repeated sampling’). In another 120 flowers from the same trees, the accumulated sugar was measured at the end of the flowering stage. The mass of the nectar sugar was determined following the washing technique. The total amount of sugar per tree was calculated by multiplying the number of flowers per tree by the average mass of nectar sugar secreted per flower. The average mass of sugar produced per flower in repeated sampling was 0.79±0.54 mg/flower (range 0.09 - 2.48 mg). The average mass of sugar per flower for each of the four investigated trees was 1.43±0.53 mg, 0.72±0.27 mg, 0.94±0.39 mg and 0.37±0.26 mg, respectively. The differences among trees was statistically significant. For accumulated nectar, the overall average mass of sugar per flower was 0.55±0.23 mg (range 0.06 - 1.29 mg) and the average values for flowers on the investigated trees of Z. spina-christi were 0.69±0.26 mg, 0.41±0.16 mg, 0.51±0.16 mg and 0.53±0.21 mg; these variations were statistically significant. The average mass of nectar sugar calculated for the flowers with accumulated nectar sampling was significantly lower than the average mass of sugar recorded for repeated nectar sugar samplings (0.79±0.54 mg). According to this study, one Ziziphus tree is estimated to produce 3.6 kg of honey (range 2.2 - 5.2 kg), equivalent to about 900 kg of honey/ha (range 550 - 1300 kg). These figures indicate the high potential value of the plant for honey production. Nectar secretion was positively correlated with temperature, indicating the adaptation of the tree to hot climates.

Oryginalną pszczołą utrzymywaną w Nepalu w ulach jest pszczoła wschodnia Apis cerana. Niedawno wprowadzono do Nepalu, egzotyczną dla tego kraju pszczołę Apis mellifera. Pszczoła ta produkuje więcej miodu niż pszczoła wschodnia. Jednakowoż właściwą gospodarkę pasieczną dla tej pszczoły w Nepalu trzeba dopiero opracować. Dlatego przeprowadzono badania mające wskazać, jaka metoda gospodarki zapewnia maksymalne korzyści dla pszczelarzy. W ciągu trzech lat badano jak początkowa siła rodziny oraz sposób dodawania nadstawek wpływa na cechy biologiczne i produkcję miodu. Badano również korzyści finansowe. Rodziny okrywające początkowo 5, 10 lub 20 plastrów (Pl) albo nie otrzymywały nadstawki albo dodawano im pół nadstawkę lub całą nadstawkę z plastrami. Stwierdziliśmy, że rodziny o początkowej sile 5, 10 lub 20 Pl posiadały w ciągu sezonu średnio odpowiednio 10,9, 14,9 i 19,4 tysięcy komórek czerwiu (Tab. 1). Średnia liczba zbieraczek wylatujących w ciągu 5 min z ula rodzin o początkowej sile 5, 10 i 20 Pl wynosiła odpowiednio 207, 349, 591 (Tab. 2). Najsłabsze rodziny o początk owej sile 5 Pl bez nadstawki wyprodukowały średnio 30,1 kg miodu. Rodziny średniej siły okrywające początkowo 10 Pl bez nadstawki, z półnadstawką i pełną nadstawką wyprodukowały średnio odpowiednio 34,1, 47,5 i 62,2 kg miodu. Natomiast najsilniejsze rodziny o początkowej sile 20 Pl z półnadstawką i pełną nadstawką wyprodukowały odpowiednio 68,2 i 74,5 kg miodu (Tab. 3). Tak więc najsilniejsze rodziny okrywające początkowo 20 Pl z pełną nadstawką wyprodukowały 2,5 raza więcej miodu niż rodziny o początkowej sile 5 Pl bez nadstawki. Jednak, gdy obliczono stosunek dochodu do kosztów produkcji, to okazało się, że był on najkorzystniejszy (1,52: 1) dla miodu wyprodukowanego przez rodziny o początkowej sile 10 Pl z pełną nadstawką (Tab. 4). Tak więc gospodarka pasieczna z pszczołą miodną A. mellifera, z rodzinami o początkowej sile 10 Pl z pełną nadstawką jest zalecana dla pszczelarzy w południowym Nepalu. Ekonomiczny aspekt oceny powyższych metod gospodarki pasiecznej ma również globalne znaczenie.