End of the road for ants that caused motoring headache

An ant has helped cause six years of delays to a Welsh road scheme. But now agreement has been reached on a way of conserving the social insect and saving the crumbling A470 north-south trunk route from further collapse.

On the roadside at Comins Coch, near Machynlleth, lives Wales' second largest colony of the red wood ant, Formica rufa. It is rare in the principality, but not in England.

The hillside road needed work to counter subsidence. For six years it has had temporary traffic lights, reducing a half-mile stretch to single carriageway.

Powys County Council had the job of restoring the road, on behalf of the Welsh Office. The fate of the ants has been a major consideration, and the county has taken advice from an invertebrate ecologist at the Countryside Council for Wales (CCW) on the least destructive way of carrying out the work.

Agreement has been reached on a road alignment which will destroy 12 of the 29 ant nests in the area. But the CCW is confident the ant will continue to flourish locally.

Last autumn, a few of the nests in the path of the roadworks were deliberately disturbed using shovels, in the hope that this would encourage the ants to move to abandoned nests near by. But the CCW will not know whether this has worked until the spring. The main roadworks should begin this summer.

Work on the road will be a relief, not only to local people, but to thousands of motorists from the Midlands who use the A470 to reach popular mid-Wales coastal resorts such as Aberdovey, Borth and Barmouth each summer.

Tom Breese, a farmer who owns land beside the stretch of road, said he had been annoyed by the lengthy delay in carrying out the remedial work.

"I have known there were ants there since I was a kid but I didn't realise they were rare,'' he said. ''These days it seems animals get more attention than humans.''

tAnts appear to be able to place themselves on a war footing by breeding extra soldiers when threatened by an enemy, scientists have found.

Researchers studied a type of ant, Pheidole pallidula, whose colonies contain ''minor" workers, which forage for food and look after young, and large-headed soldiers for defence.

When a potential enemy in the shape of a foreign colony was detected, the relative number of soldiers increased.

The experiment, led by Laurent Keller of the Institut de Zoologie et d'Ecologie Animale, at the University of Lausanne, Switzerland, is the first to show social insects altering their caste ratios in response to the environment.

The findings are published in the science journal, Nature