Currently, only two Asian giant hornets, fondly known as “murder hornets,” have been spotted in the United States. However, the immense pressure elicited from governmental bodies, private citizens, and local beekeepers nationally to eradicate the hornets is appropriate considering the severe threat they pose to honeybees.
The Asian giant hornet, or Vespa mandarinia, is the largest hornet in the world, with its female workers growing to approximately an inch and a half in length; in comparison, the average length of a female worker honeybee is only 12-15 mm. In addition to its monstrous body size, the Asian giant hornet has sizable mandibles that allow it to decapitate and dismember approximately 40 honeybees in a single minute. After slaughtering the colony, the hornets then proceed to fly the thoraxes of the deceased honeybees and the defenseless, developing larvae to their own colonies to feed their young.
Native to Asia, V. mandarinia ranges longitudinally from Russia to Japan and latitudinally from Russia to Thailand and Myanmar. Asian honeybees, or Apis cerana, whose native range overlap with that of the Asian giant hornet, are equipped with defenses that protects them from being massacred by these predatory hornets. After finding a honeybee colony, a “messenger” Asian giant hornet will release a pheromone to signal to other female workers the location of the hive. However, the Asian honeybees too respond to the pheromone. The honeybees will form a “bee ball” around their predator and begin to vibrate their flight muscles. This collective movement orchestrated by the entire colony, which may contain up to 400 honeybees, raises the temperature of the hive to 114.8℉ and elevates the carbon dioxide concentrations to harmful levels. At this extreme temperature, which is only 1℉ less than the maximum temperature honeybees can withstand, effectively kills the hornet and saves the colony.
Our apiary maintains numerous colonies of European honeybees or Apis mellifera. These honeybees are essential for our nation’s economy since they contribute approximately $15 billion to the agriculture industry through their pollination of over 90 different crops. Similar to trends nationally, we have noted the decline of our campus’ honeybee population as a result of varroa mites, viral diseases, and neonicotinoid pesticides. The Asian giant hornet poses another grave threat to European honeybees since they, unlike their Asian relatives, lack defenses against these predatory insects. The European honeybee’s prey naivety ensures its inevitable decline if the Asian giant hornet is able to spread throughout the country.