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Ecological disturbance can promote or reduce community biodiversity depending on its severity. Beekeeping activities represent a type of ecological disturbance when large numbers of honey bees are introduced to a landscape and interact with the local plant and pollinator community. In this study, we characterized the effect of immediate and long-term low-density migratory beekeeping on the diversity and abundance of native bees in the Qinghai-Tibet Plateau (China). We found that the presence of apiaries and the number of honey bees reduced native bee abundances in the local bee community, likely through displacement from floral resources. However, in locations where apiaries were previously kept for decades but are not currently present, native bee abundances recovered, and phylogenetic diversity increased; yet community relative abundances and dominant species were distinct from those that had never been stocked. Our results suggest that the presence of a transient, intermediate number of migratory honey bee colonies (60–100 colonies spaced ≥15 km from each other) may represent an intermediate ecological disturbance and not permanently reduce native bee abundances past a critical threshold that may lead to local extirpation. Yet, our study demonstrates the potential for even intermediate-scale low-density beekeeping to alter native bee communities in the long-term. [ABSTRACT FROM AUTHOR]

Background Damage from insect herbivores can elicit a wide range of plant responses, including reduced or compensatory growth, altered volatile profiles, or increased production of defence compounds. Specifically, herbivory can alter floral development as plants reallocate resources towards defence and regrowth functions. For pollinator-dependent species, floral quantity and quality are critical for attracting floral visitors; thus, herbivore-induced developmental effects that alter either floral abundance or attractiveness may have critical implications for plant reproductive success. Based on past work on resource trade-offs, we hypothesize that herbivore damage-induced effects are stronger in structural floral traits that require significant resource investment (e.g. flower quantity), as plants reallocate resources towards defence and regrowth, and weaker in secondary floral traits that require less structural investment (e.g. nectar rewards). Methods In this study, we simulated early-season herbivore mechanical damage in the domesticated jack-o-lantern pumpkin Cucurbita pepo ssp. pepo and measured a diverse suite of floral traits over a 60-d greenhouse experiment. Key Results We found that mechanical damage delayed the onset of male anthesis and reduced the total quantity of flowers produced. Additionally, permutational multivariate analysis of variance (PERMANOVA) indicated that mechanical damage significantly impacts overall floral volatile profile, though not output of sesquiterpenoids, a class of compounds known to recruit specialized cucumber beetle herbivores and squash bee pollinators. Conclusions We show that C. pepo spp. pepo reduces investment in male flower production following mechanical damage, and that floral volatiles do exhibit shifts in production, indicative of damage-induced trait plasticity. Such reductions in male flower production could reduce the relative attractiveness of damaged plants to foraging pollinators in this globally relevant cultivated species. [ABSTRACT FROM AUTHOR]

The genus Bombus (bumble bees) includes approximately 265 species, many of which are in decline in North America and Europe. To estimate colony abundance of bumble bees in natural and agricultural habitats, sibship relationships are often reconstructed from genetic data with the assumption that colonies have 1 monandrous queen. However, some species such as the North American common eastern bumble bee (Bombus impatiens Cresson) can display low levels of polyandry, which may bias estimates of colony abundance based on monandrous sibship reconstructions. To accurately quantify rates of polyandry in wild and commercially mated queens of this species, we empirically estimated mating frequencies using a novel statistical model and genotypes from 730 bees. To genotype individuals, we used a highly polymorphic set of microsatellites on colonies established from 20 wild-caught gynes and 10 commercial colonies. We found multiple fathers in 3 of the wild colonies and 3 of the commercial colonies. This resulted in average effective mating frequencies of 1.075 ± 0.18 and 1.154 ± 0.25 for wild and commercial colonies, respectively. These findings agree with previous reports of low rates of polyandry for B. impatiens. Using a large empirical dataset, we demonstrate that assuming monandry for colony abundance estimation in species that violate this assumption results in an overestimation of the number of colonies. Our results emphasize the importance of studying mating frequencies in social species of conservation concern and economic importance for the accuracy of colony abundance estimation and for understanding their ecology and sociobiology. [ABSTRACT FROM AUTHOR]

Bee monitoring, or widespread efforts to document bee community biodiversity, can involve data collection using lethal (specimen collections) or non-lethal methods (observations, photographs). Additionally, data can be collected by professional scientists or by volunteer participants from the general public. Collection-based methods presumably produce more reliable data with fewer biases against certain taxa, while photography-based approaches, such as data collected from public natural history platforms like iNaturalist, can involve more people and cover a broader geographic area. Few efforts have been made to quantify the pros and cons of these different approaches. We established a community science monitoring program to assess bee biodiversity across the state of Pennsylvania (USA) using specimen collections with nets, blue vane traps, and bowl traps. We recruited 26 participants, mostly Master Gardeners, from across the state to sample bees after receiving extensive training on bee monitoring topics and methods. The specimens they collected were identified to species, stored in museum collections, and the data added to public databases. Then, we compared the results from our collections to research-grade observations from iNaturalist during the same time period (2021 and 2022). At state and county levels, we found collections data documented over twice as much biodiversity and novel baseline natural history data (state and county records) than data from iNaturalist. iNaturalist data showed strong biases toward large-bodied and non-native species. This study demonstrates the value of highly trained community scientists for collections-based research that aims to document patterns of bee biodiversity over space and time. [ABSTRACT FROM AUTHOR]

We describe and characterize eight polymorphic microsatellite loci for the orchid bee species Eulaema meriana, an abundant species and important pollinator in wet lowland forests in tropical America. We also tested the cross-species amplification of these microsatellite loci in seven other species of the genus Eulaema. For E. meriana, number of alleles per locus ranged from four to nine and expected heterozygosity ranged from 0.377 to 0.854. Seven out of the eight loci described amplified in all seven other Eulaema species. These microsatellite loci will be of practical use for population structure, mating system and inbreeding studies in euglossine bees.

Colonies of the western honey bee, Apis mellifera L., are comprised of tens of thousands of genetically related individuals that can easily share and spread pathogens. Honey bee colonies exhibit variations in disease susceptibility that can translate into highly variable pathogen replication among individuals within a colony, between colonies, and between stocks. Here, we investigate the degree of variation in viral titers of common honey bee viruses (DWV-A, DWV-B, IAPV, LSV2, BQCV) within colonies and between colonies of five honey bee stocks in the United States. Our results showed high intra-colony variation in DWV-A, DWV-B, IAPV, and LSV2, but not in BQCV titers. However, the level of variation was not consistent across stocks. Here, we empirically demonstrate that there is significant intra-colony variation in viral titers and that some stocks are more prone to this variability. Our results highlight the need for further studies comparing virus susceptibility among stocks. [ABSTRACT FROM AUTHOR]

Long-horned bees (Apidae, Eucerini) are found in different biomes worldwide and include some important crop pollinators. In the Western Hemisphere, Eucerini received extensive taxonomic study during the twentieth century, resulting in several revisions of its genera. In contrast, progress on eucerine phylogenetic research and the genus-level classification has been slow, primarily due to the relatively homogeneous external morphology within the tribe and the rarity of many of its species in collections. Here, we present a comprehensive phylogenetic study of Eucerini based on ultraconserved elements, including 153 species from nearly all genera and subgenera and from all biogeographic regions where they occur. Many of these specimens are from museums and were collected as far back as 1909. We discuss the challenges of working with specimens with highly degraded DNA, present insights into improving phylogenetic results for both species-tree and concatenation approaches, and present a new pipeline for UCE curation (Curation of UltraconseRved Elements—CURE). Our results show the existence of seven main lineages in Eucerini and most of the genera and subgenera to be reciprocally monophyletic. Using a comprehensive and up-to-date phylogenetic framework, we: (1) propose taxonomic changes, including a new subtribal classification and reorganized generic and subgeneric limits; (2) estimate divergence times; and (3) conduct a detailed exploration of historical biogeography of long-horned bees. We find that eucerine lineages expanded their range onto most continents only after their initial diversification in southern South America during the Eocene. [ABSTRACT FROM AUTHOR]