In Italy, Colonies of Red Imported Fire Ants Discovered, Potentially Spreading Across Europe

Invasive non-native ant species have established colonies in Italy and may rapidly spread across Europe to the United Kingdom due to global warming, warns research from the Institute of Evolutionary Biology's Laboratory of Diversity and Evolution. This is reported by The Guardian.

The red imported fire ant, Solenopsis invicta, possesses a potent sting, causing harm to crops and potential damage to electrical equipment, including vehicles and computers.

These ants, considered one of the most destructive invasive species, can rapidly form "supercolonies" with multiple queens. These colonies prey on invertebrates, larger vertebrates, and plants, destroying local flora and displacing indigenous ants, insects, and herbivores in their quest for food.

The red imported fire ant ranks as the fifth most costly invasive species worldwide, spreading through human trade from its native South America to Mexico, the Caribbean, Australia, and the United States, causing annual losses of $6 billion.

Researchers discovered 88 nests of red imported fire ants on 5 hectares (12 acres) near the city of Syracuse in Sicily, Italy. Genetic analysis in the study, published in Current Biology, suggested that invasive colonies might have originated from China or the United States.

Roger Vila, the lead researcher at the Institute of Evolutionary Biology's Laboratory of Diversity and Evolution, who conducted the study, said, "Coordinated efforts for early detection and rapid response in the region are crucial for successfully managing this new threat before it spreads uncontrollably."

The charity Buglife has called for the UK government to ban soil imports, as invasive ant species easily spread when soil is imported into Britain. While the EU has prohibited soil exports from the UK, the UK has not reciprocated, largely due to horticultural trade.

David Smith from Buglife said, "This is an open door for non-native soil-dwelling species. There is widespread concern about these non-native invasive ant species, and this is one on the cusp of arriving in Europe."

Previously, in Europe, this ant species was found in imported goods in Spain, Finland, and the Netherlands, but its presence in the wild on the continent had never been confirmed.

While the EU updated its list of "invasive alien species of Union concern" to include the red imported fire ant, the British government has not updated its list since Brexit, despite experts' calls to address new invasive species.

Smith added, "We are increasingly frustrated by the delays in government biosecurity measures."

Australia spends AUD 400 million (GBP 205 million) on eradicating ants, but it has faced criticism for not acting decisively enough to remove this species. New Zealand is the only country that has successfully eradicated the red imported fire ant since its arrival in 2001.

The red imported fire ant is a heat-loving species, but researchers have concluded that it could settle in approximately 7% of Europe. In today's climate, half of Europe's urban areas would be climatically suitable for this species, including major cities like London, Paris, Rome, and Barcelona. With global warming, the continent will become even more suitable for the species, facilitating its spread across Europe.

Coastal Mediterranean cities are particularly conducive to ants, and their seaports could contribute to their spread.

Matteo Menchetti, the lead author of the study, said, "The public can play a key role in detecting S. invicta, as it is often found in urban and suburban areas. This ant can be identified by its painful stings and characteristic mounds, although expert confirmation is needed."

The Sicilian colonies are located in a lagoon and a natural park in the suburbs of Syracuse. Researchers believe that flying ant queens arrived there from the port of Syracuse to the northwest. The team recommended continuing monitoring at the port.