 The Asian, or Japanese hornet is the largest and most fearsome hornet in the world. It can be as big as 45 mm long (that's almost 2 inches), and its stinger is over 6 mm in length (a quarter of an inch!).The venom from this hornet contains an enzyme which will dissolve bone and tissue, and can be fatal if the person stung is small, or has an allergic reaction. More than 40 people are killed each year by stings from this hornet. Those who have been stung and lived have described its sting as excrutiatingly painful. The Asian giant hornet can be found in Eastern Asia, including the mountains of Japan. This hornet is not only large, but looks unusual; its head is orange, and wider in proportion to its body than other hornets. Its wingspan is up to three inches, and it makes a dull low (but loud) sound when flying. 
The queen hornet lays thousands of eggs, which develop into larvae in about a week. Very soon after that, large numbers of hornets leave the nest in search of food ... usually other insects. Bees, other types of hornets, and large insects such as praying mantises are all easy prey for the giant hornets, which often hunt in swarms.Just one of these hornets can kill 40 honey bees in a minute; a few of them can slaughter 30,000 bees within an hour or two, leaving a pile of severed heads and limbs behind. When the hornets attack a bee nest, they are looking for bee larvae, which they carry away to feed to their own young. 
The giant hornets feed their young by chewing their victims into a paste that they feed to their offspring. This paste includes special amino acids; ingested by the larvae (photo at left), this mixture helps them grow into adults with plenty of stamina ... Japanese hornets, when hunting, can travel 100 kilometres at speeds of up to 40 km/h. When it stings its victim (and like all hornets, it can sting again and again; its stinger is barbless), the Japanese hornet injects a venom which contains a mixture of about eight different chemicals. These chemicals do several things; they dissolve tissue, they cause pain, and they release an odor that attracts more hornets. The large concentration of some of these chemicals in the venom makes the hornet's sting much more painful than that from most other hornets, and the toxic lethal effects from an entire nest of these hornets is larger than most other insects. When killing other insects, the hornet often uses its large mandibles, rather than its stinger, to crush its prey. Often it will decapitate them with a quick bite. Here is what happens to many European honey bee hives when discovered by these hornets. The first hornet to find the bee nest will leave a scent (a pheromone) to attract more hornets. Then a cloud of the giant hornets arrives, and begins killing the bees, one by one. Just a few hornets can kill all the bees in a hive within a few hours. Then the hornets enter the hive and carry off all the bee larvae, which they chew up and feed to their own larvae. 
The native Japanese honey bee, unlike its European cousin, has developed an effective defense against these giant hornet invaders.When the bees detect the pheromone left by the first hornet, they attack that hornet in a special way. They form a huge ball of bees that completely engulfs the much larger hornet. [See the photo at the left] By vibrating their muscles, the bees raise the temperature inside this ball to close to 47°C, a temperature which the bees can survive, but the hornet can't. The high temperature inside the bee ball kills the hornet. While a few of the bees may be killed by the hornet during this process, most survive, ensuring that the hive will not be attacked and destroyed. 
 In the mountain villages of Japan, the huge hornets are part of the villagers' diet, being eaten deep fried or as a sashimi. The newest sports drink in Japan contains a synthetic chemical that imitates the chemicals in the giant hornet's larval saliva; the thought is that the energy boosting capabilities it gives to the hornet might also work for humans.
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We have a short video for you to watch. It contains scenes of Japanese hornets attacking a European bee hive and killing the bees. It then shows an attack on Japaneses bees where the bees swarm the hornet and kill it by heat.