نتایج جستجو برای: bombus
تعداد نتایج: 1281 فیلتر نتایج به سال:
The ecology of all bumblebees (Bombus spp.) is similar, yet some species have declined greatly while others remain abundant. We examine whether abundance is related to diet breadth. The floral visits of bumblebees were examined on Salisbury Plain, UK. All of the species examined gathered pollen mostly from Fabaceae. All species gathered nectar from a broader range of flowers than they did polle...
The hypnorum-complex of bumblebees (in the genus Bombus Latreille, 1802) has been interpreted as consisting a single widespread Old-World species, hypnorum (Linnaeus, 1758) s. lat., and its closely similar sister species in New World, B. perplexus Cresson, 1863. We examined barcodes for evidence species’ gene coalescents within this complex, using related vagans-group to help calibrate Poisson-...
The aim of this study was to analyze the 12 species which belong to the subgenus Bombus (Thoracobombus) by identifying, collating and testing the applicability of geometrics morphometrics for distinguishing the species. This was carried out on 133 females and 42 males which were collected from various localities in Turkey. After digitizing landmarks on the right fore wings, 2-dimensional Cartes...
BACKGROUND AND AIMS Although urban gardens provide opportunities for pollinators in an otherwise inhospitable environment, most garden plants are not native to the recipient biogeographical region and their value to local pollinators is disputed. This study tested the hypothesis that bumblebees foraging in English urban gardens preferentially visited sympatric Palaearctic-range plants over spec...
Identifying specialist and generalist species is of great interest to conservation biologists, population ecologists, and population geneticists. Specialization can be quantified with or without abundant data; we contend and prove that using floral abundance data leads to better identification of specialists. This can be of importance when analyzing non-native species, such as the Hypericum per...
We conducted laboratory experiments to investigate the lethal and sublethal effects of clothianidin on bumble bee, Bombus impatiens Cresson, colony health and foraging ability. Bumble bee colonies were exposed to 6 ppb clothianidin, representing the highest residue levels found in field studies on pollen, and a higher dose of 36 ppb clothianidin in pollen. Clothianidin did not effect pollen con...
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