The Asian giant hornet (Vespa mandarinia) has arrived in North America, and in recent days photos and videos have emerged showing how viciously the insect has attacked honeybees elsewhere in the world. She has even crawled into beehives and ripped off beehives, earning her super-villain the nickname “murder hornet,” which feels disturbingly appropriate. US government agencies and local beekeepers are stepping up efforts, hoping to eradicate the hornet species before it can gain a foothold on the continent. But success could lie in the natural interaction between predator and prey, according to a new study.
V mandarin is the largest hornet in the world, and can grow to four inches long. The insect has large bite marks that enable it to behead its victims and is also capable of inflicting serious injuries on its prey.
The hornet is usually a loner, but workers from the V Mandarin will team up to kill its prey, usually other hornets. This behaviour was even practised in the name of the “occupation phase.”
US beekeepers supply billions of honeybees to pollinate at least 90% of our crops, and there are concerns that the new bird of prey could already exacerbate the deep loss of important pollinator populations.
Hornets are native to Asia, from Japan and Russia to Thailand and Myanmar (formerly Burma), Japan, China, South Korea, Taiwan, the Philippines, Indonesia and Thailand.
The first confirmed sighting in the US was a dead specimen found in Washington last December, and several of the insects were spotted in New York, California, Washington, Oregon and California in the fall of 2019. No one yet knows whether the hornets will build a “North American beachhead” near the Pacific Northwest and spread from there. But if real progress is made, it could spell trouble for the North American hornets, the rest of North America, and the world.
The iconic honeybee Apis mellifera was brought to North America from Europe by early colonists in the late 19th and early 20th centuries.
Asia is home to a handful of other Apis species, including the “Apis cerana” or “Asian honeybee.” The Asian variant appears to have had a much more positive impact on the US honeybee population than A. mellifera and has made some efforts. In some parts of the continent, A. Cerana, unlike A. mellifersiferas, is used for pollination, but it contributes an estimated $15 billion to the U.S. economy each year, according to the USDA.
When the hornets enter the nest, they surround the nearly 400 working bees, which form a tangle of buzzing insects. If you find a colony of bees, you can put a pheromone sign that says “Come, sisters, come, help your sisters get a treat here. If you put the scent on an Asian honeybee hive, the V. mandarinia workers will boo the females they are.
This vibrates the flight muscles and causes the temperature to rise to 45.9 degrees Celsius, and the carbon dioxide content in the ball also increases.
Bees can cope with the harsh conditions, but if enough hornets respond to pheromone calls, they can overwhelm the bees “defences and cause them to die.
European honeybees are at the mercy of V. mandarinia unless humans intervene. Asian relatives do not react to scent markers or form beehive balls, so they do not risk being killed if humans intervene. When the hornet is mature, it has the ability to care for its own young larvae and also for the survival of its offspring.
One potential US defense that is not currently available is to increase the genetic diversity of controlled honeybees. Beekeepers can help by installing entry traps at the entrance of the hive so that it is too narrow for bees to pass through. They can also lay traps large enough to lure the hornets to their deaths, and labor is often cheap. A large number of small traps, such as those used to drive large hornets away when they approach the hives.
At least 29 subspecies of honeybee live in Eurasia and North Africa, and at least 30 in the United States. Most US bees are descended from the Italian subspecies, known for its gentleness and honey production.
If V. mandarinia were to establish itself in the USA, this would be another stress factor for the vital European honeybee colonies. Dr David G. Miller, of the University of California, Davis, said: “This shows that countries need to preserve the genetic diversity of European honeybees so that each subspecies has the ability to produce hives.
The hornet also reminds us of the Tropilaelaps mite, which lives in hives and kills bee larvae, but weakens and deforms others in adulthood. The latter is more feared in Asia, where Varroa and Tropilaea mites are found, and sucks out the equivalent of a bee liver. In 2012, beekeepers registered more than 1.5 million cases of V. mandarinia in Europe alone. They eat our food and we already have a lot of problems with them, so they are a serious threat to our bees.
These mites are not yeti in North America, but they already pose a serious threat to beekeepers in Europe and Asia.
Tropilaelaps is a much bigger threat than V. mandarinia, partly because of its difficult – to stay in – nests, “said API research director Dr. John G. Hickey.
People stung by hornets describe the experience as being stung with a hot metal needle, and the spines are large enough to pierce the standard beekeeper’s protective gear. Milligram by milligram, the hornet venom may be less toxic than that of honeybees, but they are capable of packing large doses and can sting again and again. Beekeepers and government officials hope to eradicate V. mandarinia before the squirrels settle, though humans don’t want to deal with them either.
A recent New York Times article claimed that 50 people have died from the poison V. mandarinia in the last 20 years, according to the US Centers for Disease Control.
While experts have found ways to protect honeybees and beekeepers, bumblebees that lack these defenses will be at the mercy of their new aggressive enemy if V. mandarinia is not eradicated. It’s getting ugly, “said Dr. Michael D’Agostino, a professor of entomology at Cornell University. The key is to find and destroy the nests that are normally found underground, he says.
Sirisha B