Southern giant hornets, a species native to Asia, have been sighted in Europe for the first time, raising concerns about their potential impact on native insects.
Between 2022 and 2023, at the University of Oviedo, Spain, and his colleagues accidentally caught four giant hornets in wasp traps in Asturias, northern Spain.
A genetic analysis revealed that the four female workers they captured were southern giant hornets (Vespa soror).
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“Although beekeepers in the area had told us that they had seen strange hornets, it was a surprise to discover this species,” says Sánchez.
Southern giant hornets are usually found in warmer parts of Asia, in countries such as China, India and Thailand. The workers are up to 35 millimetres long and the queens can reach 46 millimetres. They hunt invertebrates such as butterflies, grasshoppers, honeybees and other wasp species, but also small vertebrates like geckos.
The species is closely related to the northern giant hornet (Vespa mandarinia), which reached North America in 2019, but appears to have been eradicated there.
Another Asian species, the yellow-legged hornet (Vespa velutina), is now widespread across most of Europe, having first arrived two decades ago. Their impact as predators of honeybees and native bees is a major concern, with the economic cost in France alone
If southern giant hornets spread across Europe too, they could bring “a great deal of predation pressure on highly important species”, says Sánchez, including the European hornet (Vespa crabro).
European honeybees (Apis mellifera) could also be affected, as they haven’t evolved defences against giant hornets from Asia, says at Purdue University, Indiana.
While the sting of southern giant hornets certainly isn’t pleasant, and is probably a bit worse than Europe’s native species, they aren’t really more dangerous to humans, says Taylor. “They’re not super aggressive unless they’re approached,” he says.
Sánchez and his colleagues suspect the hornet reached Spain as a stowaway in a shipment and they don’t think it is widespread in the region. “It is probable that there are only a few colonies in the vicinity of the locality where we have found it,” says Sánchez.
But it is important to act quickly, he says. “If they are not eradicated in time, we believe that they could spread throughout the north of Spain and the European Atlantic coast, as has already happened with Vespa velutina,” says Sánchez.
The best way to control the species at this early stage is by removing nests, but these hornets build these underground, which makes them difficult to find, says Sánchez. “We are currently carrying out nest searches and monitoring of nearby areas to try to control and locate the colonies.”
Ecology and Evolution
