Neonicotinoid insecticides used both in sprays and seed dressing may be responsible for the collapse of honeybee colonies.
Confused and disoriented bees
A team of scientist led by the National Institute of Beekeeping in Bologna, Italy, found that pollen obtained from seeds dressed with imidacloprid contains significant levels of the insesticide, and suggested that the polluted pollen was one of the main causes of honeybee colony collapse [4]. Analysis of maize and sunflower crops originating from seeds dressed with imidacloprid indicated that large amounts of the insecticide will be carried back to honey bee colonies [5]. Sub-lethal doses of imidacloprid in sucrose solution affected homing and foraging activity of honeybees. Bees fed with 500 or 1 000 ppb (parts per billion) of the insecticide in sucrose solutions failed to return to the hive and disappeared altogether, while bees that had imbibed 100 ppb solutions were delayed for 24 h compared with controls [6]. Imidacloprid in sucrose solution fed to the bees in the laboratory impaired their communication for a few hours [7]. Sub-lethal doses of imidacloprid in laboratory and field experiment decreased flight activity and olfactory discrimination, and olfactory learning performance was impaired [8].
http://www.i-sis.org.uk/requiemForTheHoneybee.php
Confused and disoriented bees
A team of scientist led by the National Institute of Beekeeping in Bologna, Italy, found that pollen obtained from seeds dressed with imidacloprid contains significant levels of the insesticide, and suggested that the polluted pollen was one of the main causes of honeybee colony collapse [4]. Analysis of maize and sunflower crops originating from seeds dressed with imidacloprid indicated that large amounts of the insecticide will be carried back to honey bee colonies [5]. Sub-lethal doses of imidacloprid in sucrose solution affected homing and foraging activity of honeybees. Bees fed with 500 or 1 000 ppb (parts per billion) of the insecticide in sucrose solutions failed to return to the hive and disappeared altogether, while bees that had imbibed 100 ppb solutions were delayed for 24 h compared with controls [6]. Imidacloprid in sucrose solution fed to the bees in the laboratory impaired their communication for a few hours [7]. Sub-lethal doses of imidacloprid in laboratory and field experiment decreased flight activity and olfactory discrimination, and olfactory learning performance was impaired [8].
http://www.i-sis.org.uk/requiemForTheHoneybee.php
