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Insect-mediated pollination is critical for lowbush blueberry (Ericaceae: Vaccinium angustifolium Aiton) fruit development. Past research shows a persistent presence of wild bees (Hymenoptera: Apoidea) providing pollination services even when commercial pollinators are present. We undertook the study to 1) provide a description of bee communities found in lowbush blueberry-growing regions, 2) identify field characteristics or farm management practices that influence those communities, 3) identify key wild bee pollinators that provide pollination services for the blueberry crop, and 4) identify non-crop plants found within the cropping system that provide forage for wild bees. During a 4-year period, we collected solitary and eusocial bees in over 40 fields during and after blueberry bloom, determining a management description for each field. We collected 4,474 solitary bees representing 124 species and 1,315 summer bumble bees representing nine species. No bumble bee species were previously unknown in Maine, yet we document seven solitary bee species new for the state. These include species of the genera Nomada, Lasioglossum, Calliopsis, and Augochloropsis. No field characteristic or farm management practice related to bee community structure, except bumble bee species richness was higher in certified organic fields. Pollen analysis determined scopal loads of 67-99% ericaceous pollen carried by five species of Andrena. Our data suggest two native ericaceous plants, Kalmia angustifolia L. and Gaylussacia baccata (Wangenheim), provide important alternative floral resources. We conclude that Maine blueberry croplands are populated with a species-rich bee community that fluctuates in time and space. We suggest growers develop and maintain wild bee forage and nest sites., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

This study deals with the species diversity of leaf-cutter and resin bees from three tribes, four genera, and seven subgenera of the family Megachilidae from Central India. Before this study, only a few species were known from Central India. During the surveys undertaken in 2019-2022, 10 species, including two cleptoparasitic bee species of the family Megachilidae, were collected and examined. Megachile lanata Fab. was the predominant species in all the survey locations. Seven species were discovered for the first time in Central India. This paper provides details of the Megachilidae species with an updated distribution and brief diagnosis. [ABSTRACT FROM AUTHOR]

Urbanization poses a major threat to biodiversity and food security, as expanding cities, especially in the Global South, increasingly compete with natural and agricultural lands. However, the impact of urban expansion on agricultural biodiversity in tropical regions is overlooked. Here we assess how urbanization affects the functional response of farmland bees, the most important pollinators for crop production. We sampled bees across three seasons in 36 conventional vegetable‐producing farms spread along an urbanization gradient in Bengaluru, an Indian megacity. We investigated how landscape and local environmental drivers affected different functional traits (sociality, nesting behavior, body size, and specialization) and functional diversity (functional dispersion) of bee communities. We found that the functional responses to urbanization were trait specific with more positive than negative effects of gray area (sealed surfaces and buildings) on species richness, functional diversity, and abundance of most functional groups. As expected, larger, solitary, cavity‐nesting, and, surprisingly, specialist bees benefited from urbanization. In contrast to temperate cities, the abundance of ground nesters increased in urban areas, presumably because larger patches of bare soil were still available beside roads and buildings. However, overall bee abundance and the abundance of social bees (85% of all bees) decreased with urbanization, threatening crop pollination. Crop diversity promotes taxonomic and functional diversity of bee communities. Locally, flower resources promote the abundance of all functional groups, and natural vegetation can maintain diverse pollinator communities throughout the year, especially during the noncropping season. However, exotic plants decrease functional diversity and bee specialization. To safeguard bees and their pollination services in urban farms, we recommend (1) preserving seminatural vegetation (hedges) around cropping fields to provide nesting opportunities for aboveground nesters, (2) promoting farm‐level crop diversification of beneficial crops (e.g., pulses, vegetables, and spices), (3) maintaining native natural vegetation along field margins, and (4) controlling and removing invasive exotic plants that disrupt native plant–pollinator interactions. Overall, our results suggest that urban agriculture can maintain functionally diverse bee communities and, if managed in a sustainable manner, be used to develop win–win solutions for biodiversity conservation of pollinators and food security in and around cities. [ABSTRACT FROM AUTHOR]

The reproduction process of Apis mellifera L. (Hymenoptera: Apidae) occurs in defined congregation areas where natural mating occurs and males and unfertilized queen bees from different colonies converge. This work focused on the identification and characterization of a congregation drone zone in a biogeographic region of the low montane dry forest corridor, in the upper Andean valley of Sugamuxi-Tundama, for the density of bee colonies established there, considering the climatic factors of the environment and the description of biometric characters of bees and drones collected, and which constitutes the first report of a congregation zone for Colombia. In the study area, dry summer periods predominate alternating with short winter, cloudy days, and intense cold, with thermal sensations between 8 to 19°C. The drone movement route was established with an unmanned flight vehicle, through the interaction between the vehicle and bee specimens. The path of movement of drones was established operated between 10 and 60 m in North-South direction. Specimens of worker bees were collected identifying African, European, or Eastern European lines and drones of two types, yellow and black, evaluating biometric parameters and estimating the discriminant factor. The activity of the drones, occurs in two periods of 10:00 to 12:00 hours and 15:00 to 17:00 hours, flying regularly between round trips up to a 1 km radius. This work describes a methodology for monitoring congregation areas and consolidates itself as a tool for beekeepers for the conservation of regional ecotypes through bee reproductive planning. [ABSTRACT FROM AUTHOR]

Understanding the drivers of biodiversity in cities is a central goal of urban ecology. There is currently intense scientific and public interest in the factors that influence pollinator diversity in cities and their surroundings. Existing studies point to a variety of landscape and local factors as potentially important, including urbanization (often defined as impervious surface cover in the surrounding lands), tree canopy cover and the diversity and abundance of locally flowering plants. However, few studies have sought to weigh the relative importance of these predictors of bee community metrics. Using a set of 27 residential yards chosen to represent a gradient of both urbanization and tree canopy cover at a landscape scale, we used pan trapping and netting to assess the abundance and diversity of local bee communities across the City of Ottawa, Ontario, Canada. Surprisingly, the landscape factors (urbanization and tree cover) described only a tiny fraction (< 1%) of the total variance in bee abundance and diversity across sites. This was true regardless of the scale of analysis at which the landscape factors were measured. Instead, a yard's floral richness, and, to a somewhat lesser extent, its floral abundance, emerged as the most important predictors of a yard's bee community abundance and diversity. Our study offers an important counterpoint to a growing body of work emphasizing the impacts of landscape factors on bee communities. Instead, our research suggests that improving bee floral resources by increasing the plant species richness and abundance locally is a powerful tool to support bee conservation, regardless of the level of urbanization or tree cover in the surrounding landscape. Our work highlights that the practice of promoting 'bee-friendly' plantings in private yards, currently being undertaken by a number of non-profits around the world, can play an important role in restoring and maintaining urban pollinator communities. [ABSTRACT FROM AUTHOR]

The present three-year study traces the diversity of four bee communities in fragmented pedemontane areas of Volcano Etna (Catania province, Sicily) near the Metropolitan City of Catania, under different land management regimes. The selected areas comprise two different urban parks within Catania (Parco Gioeni and Parco degli Ulivi), a Nature Reserve (Complesso Immacolatelle e Micio Conti, San Gregorio di Catania), and an agroecosystem (a citrus orchard, Aci Catena). Previous data obtained from a well-investigated area (Leucatia, north of Catania) have been used as a control for bee diversity for this study. The results include an outline of bee species richness, data on the composition of bee communities, and seasonal patterns, using several diversity indexes. The study of bee diversity shows a total of 163 species, arranged in five families. The four investigated locations include 104 species arranged in four families: Andrenidae (20 species), Halictidae (15 species), Megachilidae (31 species), and Apidae (38 species); with a similar number of species (102) recorded in the control site (Leucatia). The study highlights strong seasonal variations of bee communities in all investigated sites, with differentiated seasonal patterns, whose compositions are affected mainly by forage sources, suitable nesting sites, as well as human activities. The data obtained provide a rough but basilar framework to assess management strategies to maintain adequate levels of bee diversity, especially for those areas with moderate to high environmental fragmentation. Our findings highlight the importance of season-long sampling of bee population factors if used as indicators in ecological studies. [ABSTRACT FROM AUTHOR]

Bee communities were studied with three different conditions of land-use: 1) urban area; 2) crops and livestock; and, 3) preserved vegetation. All three conditions have elements of tropical dry forest and are in the "Sierra de Quila" Flora and Fauna Protection Area and its influence zone. Sampling was carried out throughout the year (three days per month) for each land-use condition. Bee species and their abundance were registered with the intention of knowing how changes in the vegetation are related to bee community structure (richness, abundance, and a and ß diversity). A total of 14,054 individuals from 160 species were registered. A rarefaction analysis, showed that the preserved areas had significantly greater richness and diversity. Beta diversity analysis revealed a species turnover of nearly 32% among each pair of conditions. It is concluded that the changes in land-use negatively affect richness and diversity and causes major changes in species composition of the bee community. For this reason, it is recommended that the protection of the tropical dry forest, both for this study area but also in general for Mexico, is essential to guarantee the conservation of this group of insects, which are required for the reproduction of a great number wild and cultivated plant specie. [ABSTRACT FROM AUTHOR]

• Flower size is a trait determining pollinators' attraction. • Larger flowered species have three times more species of flower visitors. • There is a morphological fit between poricidal flowers and bee size. • Regardless of the flower size, the most frequent bees make vibrations. Flower size is a crucial trait for pollinator attraction. In flowers with poricidal anthers, the plant constraints the pollinator's access to the flower's rewards by enclosing pollen grains in poricidal anthers. The pollen is only released by mechanical vibrations applied mainly by bee species during buzz pollination. Although buzz-pollinated flowers exhibit a large size variation across species, their influence over patterns of flower visitation by different pollinator species remains to be elucidated. To fill such gap, we asked how flower size influences flower visitor assemblage, especially bees, across plant species and how flower size is related to body size and vibrating behavior of the most frequent bee species. We hypothesized that the assemblage of animals, especially bees, visiting larger flowers have higher taxonomic and functional diversity than smaller flowers, and the most frequent bee species visiting larger flowers have larger body size and a mandatory vibrating behavior. To test this hypothesis, we conducted a systematic review of pollination studies that reported patterns of flower visitation in plant species with poricidal anthers, describing the relationship between flower size and flower visitor metrics. We found that large-flowered species were visited by three times more species than small-flowered species, including vibrating and non-vibrating bee species. Unlike our expectations, non-vibrating bees were largely absent from small-flowered species. The most frequent bee species visiting flowers, irrespective of flower size, exhibited vibrating behavior. The most frequent bee species visiting large flowers were twice the body size of those visiting small flowers, highlighting a morphological match between flowers and pollinators. Although larger flowers are more susceptible to interactions with exploiters, reproductive success should be favored owing to the higher probability of their interaction with vibrating, large-bodied bee species. Still, a reduction in flower size probably prevents interactions with non-vibrating bees, while favoring vibrating small-bodied bee species. [ABSTRACT FROM AUTHOR]

Many varieties of sweet cherry are self-incompatible. Therefore, sweet cherry orchards require a huge population of pollinator bees to carry out an adequate amount of pollen transfer between the different varieties. Our study was conducted to evaluate the differences in the richness and diversity of these pollinators within very closely located sweet cherry orchards, and to understand the underlying effects causing these differences. The study was conducted in the Sultandağı Reservoir (Turkey) which covers the towns of Sultandağı (Afyonkarahisar) and Akşehir (Konya). In order to avoid a sampling bias, Malaise traps were used to collect bee samples. Sampling collections were repeated for three years; from 2007 to 2009, between April and May. The traps were set in the bud-swell period and lifted in the green-fruit period. Climatic data were taken from meteorology stations near the orchards. Vegetation in the surrounding areas was also inspected. The composition of pollinator bee species was determined and compared between orchards. In total, 83 bee species and 38 plant species were recorded. It was found that Halictidae is the most abundant and richest group among the pollinator bees. The effects of the quantity of the Malaise traps on bee sampling success were also tested. It was found that one trap per 325 trees is enough for an adequate sampling. Apart from the annual fluctuations of bee richness in the orchards, general differences in the bee diversity among orchards might be affected by the surrounding vegetation and especially from different agricultural practices such as tilling the ground. [ABSTRACT FROM AUTHOR]

We assessed bee diversity and abundance in a botanical garden in the city of Buenos Aires during two consecutive spring–summer periods. Every 15 days, we collected by hand-netting bee specimens seen foraging on flowers during five-minute censuses at every entomophilous herbaceous plant. A total of 66 bee species (Hymenoptera: Apoidea) were recorded. Richness and abundance of native, generalist, and above-ground nesting (cavities) species were higher than that of exotic, specialist, and below-ground (soil) nesting ones, respectively. Social bees were more abundant, while the richness of solitary species was higher than that of social bees. Cleptoparasitic species were represented by a high number of species, even though only a few individuals were captured. Our results suggest that the studied area is an important bee reservoir within the city. [ABSTRACT FROM AUTHOR]

The article discusses research into pollen loads and bee diversity at the Bridger Plant Materials Center (BPMC) wildflower seed production facility in Montana. The facility features various flowering angiosperms which include Dalea candida, Ratibida columnifera and Pacific aster. It describes the bee sampling procedures and pollen load size and composition analysis performed. It is noted that majority of the bee species collected were honey bees and bumble bees. The relative rarity of honey bees on Ratibida columnifera is also explored.

Species richness and seasonality of a bee community were studied in a restinga area in Palhoca, Santa Catarina, southern Brazil. Twice a month during a year, from September 2004 to September 2005, bees were collected on flowers, in flight and with trap-nests. A total of 784 individuals belonging to 64 species of the families Apidae, Colletidae, Halictidae and Megachilidae were collected. Halictidae was the most rich and abundant family, followed by Apidae. Species richness peaks in summer whereas only a few species of Apidae and mainly Halictidae were active in the coldest months of the year. This clear seasonal pattern of activity appears to be a general characteristic of subtropical bee communities in Brazil. Comparison with others studies in restinga of Santa Catarina was made, as also the total apifauna of restinga in Rio Grande do Sul, Santa Catarina and Parana are presented. [ABSTRACT FROM AUTHOR]

Natural small, xeric hill prairies in forested landscapes throughout the Midwest United States often contain high diversity and unique species of some organisms because of their unusual landscape context and microclimate. We measured the diversity, richness, and abundance of the bee communities of five hill prairies located in northeastern Iowa and we compared these to values for large prairie preserves in northwestern Iowa, using a Monte Carlo resampling approach to standardize sampling effort between habitat types. We also measured the diversity and richness of the flowering forb communities at the hill prairies and we quantified percentage of the landscape at a 1 km radius in different landscape elements. Bee diversity at the five hill prairies spanned the range of diversity values for large prairies preserves, so although the hill prairies are small (<5 ha), their bee communities are not uniformly depauparate compared to larger western prairie preserves. Bee diversity was significantly related to flowering forb diversity, and may have been influenced by landscape features within 1 km—particularly the percentage of agricultural row crops and open water, which may negatively affect bee diversity at the sites. Iowa’s hill prairie bee communities were largely composed of widespread eastern species, although about 10% of the bee species have more northern or western ranges and appear to be taking advantage of the region’s unique habitat features. Given the dependence of the bee communities on the plant diversity of the sites, management of the plant community to maintain its diversity will also likely benefit bee diversity. [ABSTRACT FROM AUTHOR]

Insects provide essential ecological services in both the natural environment and in human-dominated habitats. Because pollinator declines associated with land use change have been reported across the globe, there is great concern that pollinators and the ecosystem services they provide will be negatively affected. This study examines the diversity and abundance of bee pollinators in grasslands in Boulder County, Colorado, USA. Over five years, 5,200 bees were collected in grassland plots with different levels of urbanization. Most of the difference in species composition among three levels of urbanization was due to rare species that may not have been discovered in all plots. Neither the number of species nor their abundance differed significantly among the plot types, although the trend indicated increasing diversity with increasing distance from urbanization. Most notably, measures of urbanization, such as the amount of pavement and development, were not correlated with diversity. The most important factor affecting bee abundance, particularly for ground-nesting bees, was grazing regime. Bee abundance also was positively related to the number of flowering plant species. Other studies of different insects (grasshoppers and butterflies) in these plots showed results similar to ours. In contrast, previous studies on song-birds, raptors, and rodents showed significant differences between urban edge and remote plots in terms of organism abundance and diversity. Together, these results suggest that factors other than the degree of urbanization are important in determining insect abundance and diversity. [ABSTRACT FROM AUTHOR]

• Extensive agricultural habitat supports bee diversity in coffee production forests. • Diverse farmer homesteads support bee diversity in coffee production forests. • Insect pollination contributes to early coffee fruit set. • Diverse pollinator community may increase temporal yield stability. Agricultural expansion and intensification threaten pollinator populations worldwide, potentially jeopardizing crop pollination. Although the highest rates of cropland expansion are currently found within the tropics, quantifying effects of landscape composition on tropical pollinator communities and the provided pollination services to crops has received relatively limited attention. Here, we studied the relationship between land use in the landscape matrix surrounding Ethiopian coffee production forests and their bee communities and coffee pollination services. We used pan traps to collect bees from 20 plots located in small-scale coffee (Coffea arabica) production forests of varying size in a major Arabica coffee production zone in southwestern Ethiopia. To estimate the provided coffee pollination services, we performed pollinator exclusion experiments and calculated yield stability across three years. We collected 595 bees belonging to 27 species, with the honeybee (Apis mellifera) as dominant species. We found a significant convex parabolic relationship between the non- Apis bee diversity within coffee production forests and the proportion of open agricultural land in the surrounding landscape. Pollinator exclusion resulted in a significantly lower initial, but not final, fruit set. Whereas initial fruit set was not affected by the composition of the bee community, our results indicated a positive relation between non- Apis bee diversity and temporal coffee yield stability. High proportions of fruit drop suggested that physiological stress factors may have abrogated the potential benefits of insect pollination in the final fruit set. We conclude that the agricultural land and homesteads surrounding the coffee production forests still support sufficient nesting and feeding resources for non- Apis bees, hence providing a source of potential coffee pollinators. Increasing human population in the region and the increasing demand for food may present future challenges to reconcile the required increased agricultural production with the conservation of pollinator species and pollination services. [ABSTRACT FROM AUTHOR]