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Abstract The brown honeyeater (Lichmera indistincta) is a common bird species in Australia and is a pollinator of many native plant species but there are no records demonstrating evidence of effective pollination by honeyeaters in commercial cropping systems. We observed L. indistincta visiting rabbiteye blueberry flowers at a commercial berry orchard on the Mid North Coast of New South Wales and evaluated their capacity to transfer pollen. We did this by bagging flowers to prevent visitation prior to anthesis; after anthesis, we unbagged the flowers and waited for L. indistincta visits. After a single visit, we collected the stigma and mounted it on a slide to evaluate stigmatic pollen load. We observed the birds visiting blueberry flowers and foraging on nectar. We also found that L. indistincta deposited similar amounts of pollen to other common insect pollinator species, such as honeybees and stingless bees. As the commercial berry orchard blocks are surrounded by diverse remnant vegetation, we hypothesize that the vegetation is likely providing habitat for these birds. Our results indicate that berry growers with management practices that protect and support remnant vegetation surrounding blueberry orchard blocks may benefit from higher blueberry pollination services by supporting diverse pollinators within fields.

Recent studies showed that diverse wild bee assemblages are more efficient pollinators than honeybees. In urban ecosystems pollination services are also important, for example for the reproduction of many plant species in parks, for the production of vegetables and fruits in home gardens, as well as other animals depending on bee-pollinated plants., This study investigates the effect of 'urbanity' on the abundance, species richness and community structure of wild bees foraging at city trees and quantifies the contribution of wild bees and honeybees to successful pollination. Four common city tree species in Berlin, Germany, were sampled in three parks defined as 'green spaces' and compared with trees in more 'urban areas'., In total, 57 wild bee species foraged at the observed trees representing 19 % of all known species in Berlin. Wild bee species richness showed only small differences between green spaces and urban areas even though social species were found more frequently in green areas. Wild bees visited flowers more frequently in green areas, whereas the numbers of honeybee flower visits were higher in urban areas. Wild bee but not honeybee flower visits showed a positive relationship with the reproductive success of trees., The results suggest that wild bees are important pollinators of city trees that dominate the pollinator community in green spaces. To support wild bee communities green spaces should be preserved and tree species with floral reward should be planted and preserved in urban areas. [ABSTRACT FROM AUTHOR]

This paper comprises Part II of a review of flower visitation and pollination by Diptera (myiophily or myophily). While Part I examined taxonomic diversity of anthophilous flies, here we consider the rewards and attractants used by flowers to procure visits by flies, and their importance in the lives of flies. Food rewards such as pollen and nectar are the primary reasons for flower visits, but there is also a diversity of non-nutritive rewards such as brood sites, shelter, and places of congregation. Floral attractants are the visual and chemical cues used by Diptera to locate flowers and the rewards that they offer, and we show how they act to increase the probability of floral visitation. Lastly, we discuss the various ways in which flowers manipulate the behaviour of flies, deceiving them to visit flowers that do not provide the advertised reward, and how some flies illegitimately remove floral rewards without causing pollination. Our review demonstrates that myiophily is a syndrome corresponding to elements of anatomical, behavioural and physiological adaptations of flower-visiting Diptera. The bewildering diversity of anthophilous Diptera and of the floral attractants and rewards to which they respond allows for only broad generalizations on myiophily and points to the need for more investigation. Ecological relationships between flies and flowers are critical to the survival of each group in many habitats. We require greater understanding of the significance of flies in pollination, especially in the face of recent pollinator declines. [ABSTRACT FROM AUTHOR]

Nectar-feeding bats are the heaviest pollinators exploiting flowers in a hovering foraging mode. As hovering flight is considered to be energetically costly, clinging to flowers would be beneficial from an energetic perspective. I examined the rate of oxygen consumption and carbon dioxide release during clinging flower visitation in two 10-gGlossophaga soricina(Glossophinae: Phyllostomidae) to evaluate the potential energetic benefit of clinging versus hovering. In addition, I measured the duration of flower visits of free-ranging glossophagine bats toMarkea neurantha(Solanaceae), a bat-pollinated plant that allows both hovering and clinging flower visitation. After 20 s of clinging to an artificial respiratory mask, the bats’ respiratory exchange ratio did not significantly deviate from 1, indicating the combustion of sugar. The average oxygen uptake rate equaled 1.39 ml min-1 (±0.38 SD, STPD) and the carbon dioxide release rate equaled 1.33 ml min-1 (±0.20 SD, STPD) for feeder visits longer than 20 s (n=79). Converting the oxygen uptake rate into power input yielded 0.49 W, less than a third of the power requirements for hovering for a 10-g bat. Free-ranging 10-g glossophagine bats exploited flowers ofM. neuranthafor, on average, 0.32 s ( ±0.14 SD,n=273) during hovering and for 0.39 s (±0.18 SD,n=152) during clinging visitations. A comparison between the power requirements of flower exploitation in differently sized bats indicates that clinging would benefit larger nectar-feeding bats to a greater extent than smaller species. [ABSTRACT FROM AUTHOR]

We studied the effect of floral color change on long- and short-distance attraction of insect pollinators to the herb lungwort, Pulmonaria collina. Lungwort flowers change color with age from red to blue. Young red flowers had a significantly greater pollen and nectar reward and were significantly more often unpollinated than old blue ones. Red and blue flowers both influenced long-distance attractiveness of plants, defined as the number of insect approaches towards an individual plant. After reaching a plant, flower visitors preferred to visit young red flowers. Therefore, short-distance attractiveness, defined as the number of flowers visited successively on an individual plant, was influenced mainly by the number of young red flowers. The co-occurrence of the change in reproductive ability, in amount of reward, and in flower color enabled lungwort plants to direct pollinators to reproductive, highly rewarding red flowers. The data suggest that by maintaining changed flowers lungwort plants can increase their long-distance attraction and simultaneously enhance the probability of flower visits to pre-changed flowers. Thus, we propose floral color change as a mechanism that can increase the efficiency of pollen transfer to enhance plant fitness. [ABSTRACT FROM AUTHOR]

Floral resource partitioning among stingless bees (Trigona, Meliponini, Apidae) in a lowland rain forest in Sarawak, Malaysia, was investigated using tree towers and walkways in a 4-year study that includeda general flowering period. We obtained 100 collections of insect visitors to flowers of varying floral location and shape representing 81 plant species. The tendency of 11 species of stingless bees to visit specific flowers with a particular floral location and shape was analyzed by logistic regression analysis. This analysis showed that theproportion of flower visitor collections containing Trigona fuscobalteata and T. melanocephala differed according to floral location. Theformer was frequently collected at canopy and gap flowers, whereas the latter was most often collected at understory flowers. The analysis also suggested that T. erythrogastra was more rarely collected at shallow flowers than at deep flowers. Analysis of the pollen diets of T. collina, T. fuscobalteata, T. melanocephala, and T. melina revealed that similarity of pollen sources differed among the six permutatedpairs of the four species. The lowest mean rank of similarity found was between T. fuscobalteata and T. melanocephala. This result supports the hypothesis that preference in visiting flowers in different locations leads to pollen resource partitioning. [ABSTRACT FROM AUTHOR]