The first Asian hornets discovered in Japan have been found on Tsushima Island, between Kyushu and the Korean Peninsula, prompting the local and central governments to launch an extermination program against the insects, whose stings could be fatal, researchers said Monday.
The Asian hornets, which originate in China, have had a serious effect on the ecosystem and human health in South Korea and across Europe. They are now spreading throughout the island, according to studies by Kyushu University associate professor Takatoshi Ueno, local nature enthusiasts and the city of Tsushima.
Ueno warned about the danger posed by these aggressive insects, known scientifically as Vespa velutina, if they are not exterminated.
"They have strong reproductive powers and could suddenly spread if they enter mainland Japan," he said.
Asian hornets, which can be up to 3 cm long, prey on bugs and can be persistent in attacking people who disturb their nests. They are smaller than Asian giant hornets, which are widespread here, but much more aggressive than the black-tailed hornets on Tsushima.
Ueno said that, based on his study last year, the Asian hornets on Tsushima belong to the same species that entered South Korea and Europe.
They have black bodies and red heads and abdomens, and prey on Asiatic honeybees. Many of their nests were found in the northern part of the island. They are believed to have most likely arrived by ships from South Korea, which regularly visit Tsushima, the researchers said.
The city of Tsushima has sent experts to remove any nests they find, but Ueno said current measures are insufficient because the nests are often built in treetops or on cliff faces.