Intruder alert!

When an intruder or disturbance is detected, the guard bees point their stingers in the direction of the intruder and open the plates that overlap to cover the abdomen, all the time furiously fanning their wings. Under the last segment of the abdomen lies the scent gland which produces the alarm phermone, a chemical scent that communicates danger to the hive. As the alarm scent is spread throughout the hive, more bees release alarm scent and begin to fan until the characteristic "buzzing" sound of an upset hive become audible.