How bees can be affected by pesticides
1 August 2013 Last updated at 12:24 BST
Exposure to Neonicotinoid pesticides has been shown to affect a bee's ability to navigate.
In a demonstration done by Professor Randolf Mendel in Germany, two bees were captured and fitted with tiny radio transmitters. At a feeding station, one bee was exposed to neonics.
When the bees were released, some distance from the capture site, the exposed bee was unable to find its way back to the hive.