Super-ant arrives in UK
23 September 2009
An ant species from Asia which forms super-colonies and is fatally drawn to electricity has been found at Hidcote Manor Gardens in Gloucestershire.
The ant, Lasius neglectus, has been spreading across Europe for the last 20 years, but this is the first recorded colony in the UK. Electricians at the National Trust property discovered about 35,000 dead ants in a junction box: samples sent to a university in Barcelona were confirmed as Lasius neglectus.
The ants are almost impossible to distinguish from the common black garden ant, although they behave very differently: queens live underground, mating within the existing colony rather than flying to a new one, so Lasius colonies can grow extremely large. They are also known for their attraction to sources of electricity, which stimulates them to produce a pheromone. This then brings in other ants in large numbers, occasionally causing blackouts and fires. They are otherwise not harmful to humans.
The RHS Advisory Service says gardeners should not be alarmed, as the new ants are unlikely to be any more damaging to garden plants than native ants. However, it is possible that if the new species starts appearing more widely, their habit of forming super-colonies across wide areas could mean they out-compete native ant species for food resources and reduce garden biodiversity.
“The Hidcote colony may be an isolated introduction, possibly brought in amongst the roots of an imported plant,” says principal entomologist Andrew Halstead. “But the ant is now established in several countries on the mainland of Europe, so it is likely that there could be further introductions into Britain with nursery stock.”