Harnessing the power of the Bee Ball!
The Japanese honeybees, Apis cerana japonica is a honeybee species that habituates in Japan. One of their most common arch-enemy is the Japanese Giant Hornet, Vespa mandarinia japonica. The Japanese Giant Hornet would usually destroy their hives, killing the bees for their thoraxes to feed to their larvae, and pillage their honey. A single hornet could kill up to 40 bees in a minute, rendering the Japanese honeybees extremely vulnerable to the species. However, the Japanese honeybees, which is much smaller than its counterpart, uses an interesting strategy to counter the hornets.
They would swarm around the hornet and formed a ‘bee ball’ around it. By vibrating their wings together at once, they create heat of up to 47 °C (117 °F). This proves its effectiveness for 2 reasons:
The hornet can stand up to 44–46 °C (111–115 °F) only, and will die due to the heat. The bees could take heat up to 48–50 °C (118–122 °F) and thus survives. Secondly, the Carbon Dioxide level inside the ball gets to an approximate of 3.6% high thus suffocating the hornet inside too. The bee ball last from 10 minutes all the way to 3 hours till the hornet inside the bee ball dies.
The honeybees usually kills the hornet as the hornet emits pheromonal hunting signals that may cause their allies to come forth to attack the hive. When the honeybees detect the hornet’s pheromones they usually set the trap to begin the counter-attack. The rest is history to the Japanese Giant Hornet.
Here is a short video to show how amazing this strategy is : http://www.youtube.com/watch?v=K6m40W1s0Wc
Sugahara, M., & Sakamoto, F. (n.d.). Heat and carbon dioxide generated by honeybees jointly act to kill hornets. (2009). Retrieved from http://link.springer.com.libproxy1.nus.edu.sg/content/pdf/10.1007/s00114-009-0575-0
Das, A. (2012, March 21). Japanese honeybees slow-cook hornet predator in giant bee ball, study. Retrieved from http://www.asianscientist.com/in-the-lab/japanese-honeybees-kill-asian-giant-hornet-with-hot-defensive-bee-ball-2012/