The largest hornets in the world have been reported in the U.S., causing many to wonder how dangerous these black and orange insects could be to our ecosystem.

The Asian giant hornet is also known as the Japanese giant hornet and murder hornet. They are native to Asia and range from Japan and Russia to Thailand and Myanmar (formerly Burma). However, they were first discovered in the United States in Washington in the fall of 2019. Only two hornets were discovered at that time, but since then, two new, unconfirmed sightings have been reported in April 2020. These hornets most likely came to the United States as invisible blind passengers in packing boxes.

Top facts about giant Asian hornets

  • Asian giant hornets can grow to be 2 inches long
  • Your wing span reaches more than 3 inches long
  • Only women have spines that can reach 0.2 inches in length
  • Her stings provide a powerful neurotoxin that contains almost seven times as much poison as a honey bee
  • Asian giant hornets can sting again and again
  • Almost 50 people die of murder hornet stings in Japan every year, mainly due to allergic reactions
  • However, multiple stings can kill people even if they're not allergic

Murder hornets attack honeybees

Murder hornets are an important predator of the European honey bee. The biggest fear of these hornets is the harm they do to honeybees, which are responsible for most of the pollination of plants in the U.S. Honeybees contribute an estimated $ 15 billion to the US economy each year through their pollination services, far more than any other managed bee, according to the Scientific American.

Honeybees

Hornets are most destructive in late summer and early fall when they're looking for protein sources to raise next year's queens. This is the time when the Asian giant hornets attack honey beehives. Attacks on beehives occur in three phases …

  1. First, the hornets chase individual bees out of a beehive that has been chemically marked by another hornet. Once caught, the hornets tear the bees to pieces and carry the dismembered parts back to their beehive and feed them to their own larvae.
  2. Next comes the slaughter phase, in which dozens of hornets attack the beehive and massacre tens of thousands of bees. "Within a few hours, a strong, healthy, and populous honeybee colony of 30,000 to 50,000 workers will be slaughtered by a group of 15 to 30 hornets," said a Washington State University report.
  3. In the last phase, the hornets move into the defeated beehive and feed on the abandoned larvae and pupae, make a "bee paste" and bring them back to their beehive and feed them their own young. The hornets are very aggressive in this phase and can attack animals or people who migrate too close to the occupied beehive.

The Murder Hornet was originally sighted near Blaine, WA and on Victoria Island in Vancouver, BC. No hornet sticks were found, but spring is the mating season, so there are numerous warnings in Washington.

Further information on Murder Hornet can be found in the WSU Fact Sheet.