The behaviour of queen honeybees and their attendants

Abstract. The behaviour of queen and worker honeybees (Apis mellifera L.) was observed using small colonies in observation hives. Workers paid more attention to queens which had been mated for 2 months or more than to those which were newly mated; virgin queens received least attention. Queens received most attention when they were stationary and least when they were walking over the comb; virgin queens were most active. Queen cells had as many attendants as virgin queens and queen larvae were inspected almost continuously. The queen pheromone component 9–oxo-trans-2–decenoic acid stimulated 'court' behaviour when presented on small polyethylene blocks, but workers responded aggressively to complete extracts of queens' heads. Both the heads and abdomens of mated queens received much attention from court workers but the abdomens were palpated by more workers for longer and were licked much more. The queens' thoraces were least attended. Abdominal tergites posterior to tergite glands were licked for longer than those anterior to the glands. Only worker bees very near to the queen reacted to her and joined her 'court'.
No evidence was found of a diel periodicity in the behaviour of a queen or her 'court'. During the winter the queen's court was smaller than in summer and she walked less and laid fewer eggs. When colonies were fed with sucrose syrup in winter, their queens laid more eggs and workers reared more brood but there was no change in the attention received by the queens.
The implications of these findings for the secretion and distribution of queen pheromones are discussed.     

Dioecy in the endemic genusDendrocacalia (Compositae) on the Bonin (Ogasawara) Islands

Dendrocacalia crepidifolia Nakai (Compositae, Senecioneae), the only species of this arboreal genus endemic to Haha Island in the Bonin Islands, was found to be dioecious. Male flowers differ from female ones in having a stunted style (style in female exserted from corolla and deeply bifurcating) and anthers filled with fertile pollen (anthers in the female lacking pollen). The size of the corolla and number of florets per head were similar between male and female flowers. The crown area of this arboreal species was also similar in male and female plants. The sex ratio was 0.55 male, not significantly different from 0.5. Both sexes produced nectar of similar sugar concentration (ca. 50%). The flowers are pollinated by feral honeybees (Apis mellifera), but they are thought to have been pollinated by small, lesshairy, endemic solitary bees before honeybees were introduced and subsequently became the dominant bee species on the island. The evolution of dioecy ofDendrocacalia on the island is thought to stem from the deleterious effects of inbreeding that are inherent in plants with geitonogamy. The increased geitonogamy on the island has resulted from increased woodiness (i.e., increased number of flowers per plant) and the original dependence on endemic bee pollinators, which are now endangered.     

Assessing the effectiveness of foraging radius models for seabird distributions using biotelemetry and survey data

Relatively simple foraging radius models have the potential to generate predictive distributions for a large number of species rapidly, thus providing a cost-effective alternative to large-scale surveys or complex modelling approaches. Their effectiveness, however, remains largely untested. Here we compare foraging radius distribution models for all breeding seabirds in Ireland, to distributions of empirical data collected from tracking studies and aerial surveys. At the local/colony level, we compared foraging radius distributions to GPS tracking data from seabirds with short (Atlantic puffin Fratercula arctica, and razorbill Alca torda) and long (Manx shearwater Puffinus puffinus, and European storm-petrel Hydrobates pelagicus) foraging ranges. At the regional/national level, we compared foraging radius distributions to extensive aerial surveys conducted over a two-year period. Foraging radius distributions were significantly positively correlated with tracking data for all species except Manx shearwater. Correlations between foraging radius distributions and aerial survey data were also significant, but generally weaker than those for tracking data. Correlations between foraging radius distributions and aerial survey data were benchmarked against generalised additive models (GAMs) of the aerial survey data that included a range of environmental covariates. While GAM distributions had slightly higher correlations with aerial survey data, the results highlight that the foraging radius approach can be a useful and pragmatic approach for assessing breeding distributions for many seabird species. The approach is likely to have acceptable utility in complex, temporally variable ecosystems and when logistic and financial resources are limited.     

Occurrence of vitellogenin in drone honeybees (Apis mellifica)

Summary

The occurrence of vitellogenin in adult haploid drones of the honeybee, Apis mellifica, was determined by sensitive immunotechniques, i.e. two-dimensional Immunoelectrophoresis and SDS-PAGE immunoblotting using a monospecific anti-vitellogenin-serum. In drones vitellogenin is one of the minor fractions of the hemolymph proteins. Genetic and regulatory aspects of vitellogenin synthesis in male bees are discussed.     

The influence of hybridization between African and European honeybees, Apis mellifera, on asymmetries in wing size and shape

Abstract We examined the possible role of hybridization in the invasion process of the African honeybee by testing two hypotheses regarding fluctuating asymmetry (FA), a measure of developmental stability, in wing characteristics: (1) FA should be higher in hybrid versus parental genotypes of African and European races; (2) FA should be lower in African bees compared to hybrid and European workers. Parental and reciprocal hybrid worker genotypes were cross fostered in common-hive rearing environments. We did not find greater FA for wing size and shape in the hybrids compared to both parental types. However, we did find significantly lower FA of shape in the African workers compared to the European and hybrid workers, suggesting that European bees and their hybrids may have compromised fitness relative to African bees. We also found that the two hybrid genotypes significantly differed in overall wing size and shape. If these differences affect wing aerodynamics, then the paternity of hybrids may influence worker performance and could potentially contribute to the loss of European matrilines. Hybridization had few consistent effects on directional asymmetry for wing size and shape. Genotypic factors played a far greater role in determining the effect of hybridization on wing morphology than did differences in rearing environment. Thus, African bees may have lower FA for wing shape (and by inference greater developmental stability) relative to European and hybrid workers, which may contribute to the ability of African bees to displace European honeybee races in invaded regions.     

Mitochondrial DNA variability in the Canary Islands honeybees (Apis mellifera L.)

The mitochondrial DNA (mtDNA) of individuals from 79 colonies of Apis mellifera from five Canary Islands was studied using the Dra I test based on the restriction of PCR products of the tRNAleu–COII intergenic region. Five haplotypes of the African (A) lineage and one of the west European (C) lineage were found. The haplotypes A14 and A15 are described for the first time. These haplotypes have a new P sequence named P₁. The wide distribution and high frequency of haplotype A15 suggest that it is characteristic of the Canarian Archipelago. Sources of haplotype variability of honeybee mtDNA in the Canary Islands (waves of colonization from Africa, queen importations, habitat diversification) are discussed.     

Dopamine influences locomotor activity in honeybee queens: implications for a behavioural change after mating

Abstract Dopamine has been suggested to be involved in physiological and/or behavioural changes triggered by mating in European honeybee (Apis mellifera) queens but its specific role remains unclear. In the present study, the amounts of dopamine (DA) and its metabolite, N‐acetyldopamine (NADA) are measured, in queens of various ages to clarify the association with locomotor activity. The effects of DA receptor agonist/antagonist drugs on locomotor activity are further investigated. Brain levels of DA and NADA are relatively constant during the period before mating when locomotor activity reportedly increases with age but decreases in 1‐year‐old laying queens with low locomotor activity. Reduced DA and NADA levels are also found in haemolymph of 1–3‐month‐old laying queens. When a DA receptor agonist or antagonist is injected into 6‐day‐old virgin queens, locomotor activity levels increase significantly with 2‐amino‐6,7‐dihydroxy‐1,2,3,4‐tetrahydronaphthalene (agonist), and decreased with cis(Z)‐flupenthixol (antagonist). These results suggest that DA systems are involved in the motor control of honeybee queens, and that the decline in DA levels reduces locomotor activity after mating but increased locomotor activity before mating may be independent of DA levels.