Index – Foreign – Killing of horse wasps decimates North America’s bee population



[ad_1]

Local authorities on the US Pacific coast and the Canadian province of British Columbia are already considering how to get rid of the dangerous insects. Only seven nests have been identified in the Canadian region. The insects that spread here, originating from Korea, Japan and mainland Asia, have killed several bee hives.

Several similar cases have been recorded in neighboring Washington state. There, the wasps also pinched people. Stinging a bite is much more painful than any other insect.

This is understandable, as the wasp grows much larger than its somewhat more peaceful relatives.

The largest specimen found in North America to date was 4.5 inches long, and its body length was increased by another 6 millimeters by the sizable sting.

However, a new subspecies discovered in China is even larger. A specimen with a wingspan of 9.35 centimeters was discovered in Yunnan province, China, along the border with Myanmar. The body length of the robotic wasp is 6 centimeters and the inside diameter of its hive reaches two meters. Experts have collected hundreds of specimens of the hideously large Asian giant wasp (Vespa mandarinia). Scientists believe that the queen of the breed is even bigger than the workers.

Horse wasps generally settle in wooded mountainous areas and occupy the nests of rotting trees first. They feed on other insects, especially caterpillars, but neither do they despise tree sap or honey.

Destroy bee colonies

“An attack with a Vespa mandarina by a few dozen workers could kill between 25 and 30,000 bees in just a few hours,” warns Conrad Bérubé. According to a Canadian beekeeper and entomologist, equine wasps pose a great threat to beekeeping and the entire industry associated with it.

Japan spends 7.5 billion guilders a year in yen to destroy horsehair nests, South Korea 60 percent. In the United States, eradication of equine wasps consumes $ 30 million (HUF 9 billion) a year.

Bérubé herself participated in an equine wasp eradication operation on Vancouver Island in November 2019. She was more careful than usual.

He reinforced his protective suit with Kevlar straps on his wrists and ankles, but suffered at least seven stab wounds. Pain is like “hitting my body with hot pins,” he recalls his excruciating experiences.

The slaughter of wasps can be blamed for the death of approximately 50 people a year in Asia. An attempt was made to protect the hives in Canada by trapping them and narrowing the entrance, but “none of the procedures were sufficient or effective,” said the beekeeper.

Like other invasive or artificially introduced species in other parts of the world, horse wasps have no natural opponents. The local flora and fauna have not developed effective defense mechanisms since they have not previously been exposed to such a threat.

American bees, for example, unlike Japanese bees, have not learned to defend themselves against them at all, so even a single Asian hornet can exterminate an entire hive in a matter of hours.

In Blaine, Washington, the first Asian horse wasps were captured in July 2020. They flossed a miniature radio transmitter over them, and one of them eventually led entomologists to the tree hiding the ball-sized nest. of basketball. The nest could hide from 100 to 200 wasps. Researchers in protective gear sniffed the insects out of their nest through a pipe. They also cut down the entire tree to make sure they had destroyed all the pests and to see if the queens had left the nest earlier so that they could establish more and more nests.

Cruel predators

“Although wasps are cruel predators, there are also many misconceptions about them,” says Kevin Short, a professor at the University of Tokyo who has been studying insects for 35 years.

In the Japanese media, they are called “killer” wasps.

However, this is misleading and misleading, as its function is particularly useful. After being fed by the caterpillars, they are destroyed, thus protecting the crop, which in turn would be destroyed by the caterpillars, says the professor. Kevin Short says Japanese growers “welcome” the presence of equine wasps.

During his decades of research, Short was not stung by a single wasp. He says:

They only attack if they feel that their home, their nest is in danger, and only in late fall when they prepare for the queen’s nest next year.

Bees, according to the professor, have developed an effective defense mechanism against wasps. Formed into a “ball”, they move and move around the wasps that attack their hives, generating heat. The intruder’s body temperature suddenly reaches the point where the insect gives up, boils, and dies.

Bees planted in Europe and North America have yet to master this trick. Instead of an organized attack in a swarm, they fly one by one over the wasp, which simply decapitates the bees with its strong jaw.

The entry route

In Canada and the United States, it has not yet been possible to map how insects native to Asia have reached North America.

Probably similar to France, says Bérubé. Wasps that hid among pots from China settled there.

Presumably, the wasps arrived in the same way to North America, where Chinese pots are sold in horticulture. The pots are, moreover, a great winter hideout among insects.

According to Berubé, detailed examination of shipments from Asia and immediate destruction of discovered colonies could prevent the massive spread of wasps.

(Top image: A Washington State Department of Agriculture employee walks behind a tank of giant Asian horns taken from a wooden nest. October 24, 2020 in Blaine, Washington. Photo: Elaine Thompson / POOL / AFP)



[ad_2]