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Patterns of widespread decline in North American bumble bees
It is shown that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23–87%, some within the last 20 y, although cause and effect remain uncertain. Expand
Effect of human disturbance on bee communities in a forested ecosystem.
The results suggest that at least in this system, moderate anthropogenic land use may be compatible with the conservation of many, but not all, bee species. Expand
Sampling Bee Communities (Hymenoptera: Apiformes) in a Desert Landscape: Are Pan Traps Sufficient?
Though pan trapping constitutes a standardized method that avoids collector bias, it may not be unbiased; capture rates were lowest when flowering plant richness was greatest, and net collecting should be used in addition to pan traps if comprehensive inventories are desired. Expand
Interspecific geographic distribution and variation of the pathogens Nosema bombi and Crithidia species in United States bumble bee populations.
In a nationwide survey of the US, nearly 10,000 specimens of 36 bumble bee species collected at 284 sites were evaluated for the presence and prevalence of two known Bombus pathogens, the microsporidium Nosema bombi and trypanosomes in the genus Crithidia. Expand
Biodiversity Regulation of Ecosystem Services
Coordinating Lead Authors: Sandra Dı́az, David Tilman, Joseph Fargione Lead Authors: F. Stuart Chapin III, Rodolfo Dirzo, Thomas Kitzberger, Barbara Gemmill, Martin Zobel, Montserrat Vilà, CharlesExpand
Substrates and Materials Used for Nesting by North American Osmia Bees (Hymenoptera: Apiformes: Megachilidae)
Nesting substrates and construction materials are compared for 65 of North America’s 139 described native species of Osmia bees to indicate the range of nesting habits and materials of European species are largely comparable, although records indicate that far more European species may nest in empty snail shells. Expand
Might Flowers of Invasive Plants Increase Native Bee Carrying Capacity? Intimations From Capitol Reef National Park, Utah
It is argued that invasives with entomophilous flowers are unlikely to either facilitate the reproduction of uncommon native plants or consistently compete with them for pollinators, and are likely, over time, to selectively increase the carrying capacity and population size of native bees. Expand
Global invasion by Anthidium manicatum (Linnaeus) (Hymenoptera: Megachilidae): assessing potential distribution in North America and beyond
The wool carder bee, Anthidium manicatum, is the most widely distributed unmanaged bee in the world and its naturalization in North America, possibly through punctuated dispersal, the probability of suitable habitats across the globe and the synanthropy exhibited by this invasive species are discussed. Expand
Pyrodiversity begets plant-pollinator community diversity.
It is found that pyrodiversity is positively related to the richness of the pollinators, flowering plants, and plant-pollinator interactions, and a diversity of fire characteristics contributes to the spatial heterogeneity (β-diversity) of plant and pollinator communities. Expand
Phylogeny and biogeography of bees of the tribe Osmiini (Hymenoptera: Megachilidae).
Evidence is provided that the Osmiini originated in thePalearctic, and that extensive exchanges occurred between the Palearctic and the Nearctic, providing evidence that many osmiine species nest in wood or in stems, facilitating dispersal by overseas transport of the nests. Expand