Asian Giant Hornet Classification and Evolution
The Asian giant hornet is the largest species of hornet in the world with some queens reaching more than 5cm in length. They are found throughout Eastern Asia, particularly in Japan where they are commonly known as the giant sparrow bee. It is not to be confused with the more placid Asian hornet which arrived in France in 2005 and, although similar in appearance to the Asian giant hornet, the Asian hornet is thought to be no more dangerous than the European hornet. The Asian giant hornet was first classified in 1852 by a British entomologist called Frederick Smith, who worked in the zoology department of the British Museum. He later became the president of the Entomological Society of London from 1862 - 1863.
Asian Giant Hornet Anatomy and Appearance
This wasp species is larger than any other with average Asian giant hornets growing to between 2.7cm and 4.5cm in length, with a wingspan of around 7cm. The queens can grow to 5.5cm but are similar in appearance to the worker hornets with an orange head, black mandibles and a black and golden body. The Asian giant hornet has two sets of eyes, one compound and one ocelli, both of which are brown in colour along with their legs. Unlike other species of wasp, and indeed bees, the stinger of the Asian giant hornet is not barbed and therefore remains attached to it's body once used. This means that Asian giant hornets are able to sting their victims repeatedly, injecting a complex venom that is known to contain eight different chemicals.
Asian Giant Hornet Distribution and Habitat
The Asian giant hornet is found throughout Eastern Asia in Korea, Taiwan, China, Indochina, Nepal, India and Sri Lanka, but they are most commonly found in the mountains of Japan. They are found inhabiting higher altitude forests in both temperate and tropical areas, where there is plenty of food and suitable places to build a nest. The nest is founded by a fertilised female (known as the queen) who selects a suitably sheltered site such as the hollow trunk of a tree, where she begins to build herself a nest out of chewed up bark. Wasp nests contain a series of single cells which together create the well-known honeycomb affect.
Asian Giant Hornet Behaviour and Lifestyle
Asian giant hornets are known for their fearless and extremely aggressive attitudes, and they seem to favour one animal in particular, the honeybee. Asian giant hornets like to feed the honeybee larvae to their own young and are known to completely destroy whole bee hives in the process. Rather than using their stinger, Asian giant hornets, kill the guarding bees using their strong mandibles with extreme force and agility. One hornet is said to be able to tear up to 40 honeybees in half every minute just to get at what it wants. Asian giant hornets are sociable insects, working together within the colony to forage for food, growing the size of the nest and caring for the young. They are known as workers but they do not reproduce, as that is the job of the queen.
Asian Giant Hornet Reproduction and Life Cycles
Once having built her nest in the spring, the fertilised queen lays a single egg in each cell which hatch within a week. Asian giant hornet larvae undergo a five-stage changing process known as metamorphosis, in order to get to their adult form. This takes around 14 days by which point the hive has it's first generation of workers that ensure that the colony as a whole is well-maintained. By the late summer, the population of the colony is at it's peak with around 700 workers, most of which are female. The queen then begins to produce fertilised (female) and non-fertilised (male) eggs. The males leave the hive once they have reached their adult form and usually die once mated. The workers and current queens tend to die out in the autumn leaving the young fertilised queens to survive the winter and begin the process again the next spring.
Asian Giant Hornet Diet and Prey
The Asian giant hornet is a dominant predator within it's environment, mainly hunting other insects, particularly bees. Asian giant hornets are also commonly known to kill larger insects such as preying mantises and even other wasps and hornets. Adult Asian giant hornets are unable to digest solid proteins and instead only eat the fluids from their victims. They are also known to feed their catch to their larvae (particularly the honeybee larvae) in the form of a regurgitated paste. The larvae then secrete a clear liquid which the adults consume, and is thought to give them a bit of an energy boost. Asian giant hornets predominantly use their mandibles rather than their powerful stingers in order to secure their prey.
Asian Giant Hornet Predators and Threats
Due to the fact that the Asian giant hornet is an apex predator within it's environment, it has no real natural predators within it's native habitats. Humans pose the biggest threat to the world's largest wasp, mainly as they are consumed as part of normal diets in the areas where they are found. This is particularly common in the mountains of Japan where the Asian giant hornet populations are in the highest abundance. Despite it's size and bad temper, numbers of the Asian giant hornet are declining in certain areas. This is mainly due to habitat loss in the form of deforestation. Honeybees in Eastern Asia are also starting to develop their own defence again the hornets, trapping them in their nest until it becomes too hot for this giant wasp and it dies.
Asian Giant Hornet Interesting Facts and Features
The stinger of the Asian giant hornet is 1/4 inch long and because it has no barb, the Asian giant hornet is able to sting it's victims multiple times. The venom injected by the stinger is incredibly potent and contains eight different chemicals, each with a specific purpose. These range from tissue degeneration and breathing difficulties, to making the sting more painful and even attracting other hornets to the victim. The Asian giant hornet is a relentless hunter and only a few are said to be able to completely wipe out a 30,000+ honeybee colony in a couple of hours. The saliva produced by the larvae of the Asian giant hornet is said to give them their renowned energy and stamina when consumed on a regular basis. When chasing their prey, they have been reported travelling distances of up to 60 miles, at a top speed of 25 mph.
Asian Giant Hornet Relationship with Humans
Oddly enough, these incredibly large and indeed dangerous insects, are actually eaten by people who share the habitat of the Asian giant hornet. The Asian giant hornet is consumed by some as a regular source of food and is most commonly deep fried or served as a hornet sashimi. Despite the fact that the venom of the Asian giant hornet is incredibly potent, it is only in rare cases when the person is more vulnerable, that it is actually the poison that has caused them to die. In Japan alone, 40 people are killed every year by stings from Asian giant hornets but fatalities are mainly caused by allergic reactions, often from multiple stings.
Asian Giant Hornet Conservation Status and Life Today
The Asian giant hornet is today listed as a species that is Threatened from extinction in the near future, should the circumstances surrounding it's survival not change. Despite their dominance in their natural environments, the Asian giant hornet populations are being severely affected by habitat loss is certain areas, predominantly in the form of deforestation.