The 3,500 mile-long fence, which stretches up into Queensland from the Great Southern Bight in Western Australia, was built to keep dingoes and wild dogs out of sheep-grazing areas in the east. Kangaroos and emus regularly damage it, the camels . . .

descendants of animals brought to Australia in the 19th century to help open up the arid interior . . . have become the biggest problem.

The wild camel population, already the largest in the world, doubles every eight years, and the mating season is now in progress.

Michael Balharry, the manager of the South Australian segment of the fence, said that randy males were ramming themselves through the fence to reach females.

The dingo barrier . . . completed in the 1950s, and twice the length of the Great Wall of China . . . might have to be re-designed in certain areas, Balharry told ABC radio.

The problem was that camels could get their heads over it, he said. "If you add a bit to it, and electrify the top of it, maybe this will stop them."

Feral camels, which were released into the desert once they were replaced by cars, are regarded as a major pest.

A pack of the beasts, searching for water during Australia's prolonged drought, recently rampaged through a remote Outback community, trampling toilets, taps and air conditioners.