From The Times
October 25, 2005

Killer hornets get a taste for humans

THEIR sting is as painful as a red-hot spike piercing the flesh. They crush their helpless victims with powerful jaws. Now, after millennia spent terrorising the mountains and woodlands of Japan, flying cross-country at 25mph, they are living off sushi and kebabs – and turning on human beings.

A plague of hornets is bedevilling Japan, home to some of the most aggressive flying insects. Dry weather has allowed them to breed in record numbers, and entomologists fear a surge in deaths caused by the hornets’ agonising stings. In the past, excess hornet populations would die off because of a lack of food, but recently the hornets have moved into the cities, where they have found new forms of nutrition.

The insects have been seen sipping from discarded soft-drink cans and carrying off lumps of fish and meat from bins and rubbish bags. Local authorities are receiving double the usual number of calls from people asking them to remove hornets’ nests.

Between 20 and 40 Japanese die from hornet stings every year, more than the number killed by poisonous snakes. Evidence suggests a higher than usual death toll this year. Since August five people have died in northeast Japan alone, one of the less-populated parts of the country. Death by hornet sting is caused by anaphylactic shock, an allergic reaction leading to unconsciousness and breathing failure. “It is a pain that you can never imagine until you have experienced it”, Masato Ono, an entomologist at Tamagawa University, in Tokyo, said. He should know – he has been stung 200 times. “It is profoundly shocking, like a red-hot 15cm nail rammed into your body. I have never grown accustomed to the pain.”

The king of the hornets isĀ Vespa mandarinia japonica, a fearsome black-and-orange creature whose queen grows to be more than 5cm long. It lives in woodlands and preys mainly on other insects, such as honeybees, which it can kill at the rate of 40 a minute. With the steady destruction of its forest habitat, the numbers of giant hornets have shrunk, leading to a population surge in one of the species on which they prey – the yellow hornet, or Vespa simillima Smith.

It is the yellow hornets that have adapted to the fast-food life of the towns and cities, where the human population has grown unaccustomed to dealing with them.

Tadashige Otaka, the director of the Urgent Action Section of the city of Matsudo, said: “In the old days parents taught their children to be careful in dealing with the nests. But children these days are ignorant and sometimes try to smash the nests violently.”

Bees defend against the hornets by flocking around them to form a tight, vibrating scrum of 500 insects. The temperature in the scrum rises so high that the hornet dies, but the bees can withstand it.