نتایج جستجو برای: bombus
تعداد نتایج: 1281 فیلتر نتایج به سال:
No previous work describes natural history of coffee pollination in semi-natural habitats, but without intrusion of hived bee colonies. In Panama highlands having feral honeybees since 1985, the fruit and seed set of Coffea arabica was monitored during 1997 in bagged and open flowers on 558 shrubs in 11 transects within a range of 13 km, at elevations of 13001600 m. Caturra varieties were studi...
The regulation of protein collection through pollen foraging plays an important role in pollination and in the life of bee colonies that adjust their foraging to natural variation in pollen protein quality and temporal availability. Bumble bees occupy a wide range of habitats from the Nearctic to the Tropics in which they play an important role as pollinators. However, little is known about how...
Foraging behaviors of bumble bee workers have been examined in natural habitats, whereas agricultural landscapes, which can provide insights on ßight distances to fragmented patches of bloom,have received limited attention. Inparticular, informationonworkerßightdistances to crops blooming several months after nests have been established is invaluable. Here, we examined foraging patterns of Bomb...
Declines in bee populations have been documented in several parts of the world. Bees are dependent upon flowering plants for resources, and flowering plants often depend upon bees for pollination services. Bees can therefore serve as indicator species of habitat degradation due to these relationships with flowering plants. This study investigates how the bumble bee community in San Francisco ha...
Bumblebees were trained in biologically realistic sensorimotor tasks to test how learnt information from more than a single task is organised in memory. Bees (Bombus impatiens and Bombus occidentalis) learned to collect sucrose solution from the arms of small T-mazes. The reward was offered in the right arm of a maze when the entrance was marked blue, and in the left arm when the entrance was y...
Despite considerable interest in bumblebees and their conservation, few data are available on basic life-history parameters such as rates of nest predation and the proportion of wild nests that survive to reproduction. Here, we use a combination of data collected by volunteers and our own direct observations which together describe the fate of 908 bumblebee nests in the UK between 2008 and 2013...
The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina share the neogreg...
The conservation of insect pollinators is drawing attention because of reported declines in bee species and the 'ecosystem services' they provide. This issue has been brought to a head by recent devastating losses of honey bees throughout North America (so called, 'Colony Collapse Disorder'); yet, we still have little understanding of the cause(s) of bee declines. Wild bumble bees (Bombus spp.)...
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