 Bumblebees use a combination of colour and spatial relationships to learn from which flowers to forage . They can also detect both the presence and the pattern of electric fields on flowers , which occur due to atmospheric electricity , and take a while to leak away into the ground . They use this information to find out if a flower has been recently visited by another bee . After arriving at a flower , they extract nectar using their long tongues ( " <unk> " ) and store it in their crops . Many species of bumblebees also exhibit " nectar robbing " : instead of inserting the mouthparts into the flower in the normal way , these bees bite directly through the base of the corolla to extract nectar , avoiding pollen transfer . 
