Hedgehogs are being shot in the latest stage of the cull

It is the latest development in the agency's controversial cull to protect Uist's population of wading birds, but opponents have voiced outrage.

The cull of hedgehogs in Uist and Benbecula is entering its fourth year.

Previous culls have employed the method of trapping the hedgehogs and killing them by lethal injection.

'Unethical' slaughter

Experts at SNH said it was the only humane way to rid the islands of the mammals, which were introduced to the area in the 1970's.

However, from next month the agency said it would bring in dogs with handlers to locate the hedgehogs.

Marksmen would then use shotguns to kill the creatures because lethal injection is not permitted under the new law on hunting with dogs.

This extermination policy is turning from the bizarre to the ridiculous Uist Hedgehog Rescue

But critics of the cull have expressed revulsion.

Uist Hedgehog Rescue, a coalition of organisations consisting of Advocates for Animals, the British Hedgehog Preservation Society, Hessilhead Wildlife Rescue Trust and International Animal Rescue, say the creatures should be relocated to the mainland instead, as killing them is inhumane.

A spokesman said: "UHR is appalled at the thought of healthy hedgehogs being blasted away with shotguns.

"Is this really how the public expects their taxes to be spent by SNH, a government-funded so-called 'conservation' organisation?

"This extermination policy is turning from the bizarre to the ridiculous.

"This unethical scenario would not be necessary if SNH and the other members of the Uist Wader Project would work with UHR to catch and relocate the hedgehogs live to the mainland."

He added: "SNH exists to protect Scotland's natural heritage, not to kill it. Killing these hedgehogs is flying in the face of expert advice, decades of practical experience and public opinion."

Protect birds

Sarah Roe, of Scottish Natural Heritage, said: "There are only a few hedgehogs left on North Uist and using dogs is the best way of finding them.

"It is very important because we do not want them to breed and important to protect the birds in the area. Some of the bird's populations have declined by half.

"It is against the law to use any other method of killing the hedgehogs - it is quite clear you need to use a shotgun if you are going to use dogs."

There are around 4,000 hedgehogs across North and South Uist and Benbecula.

Previous culls were carried out on the islands in spring 2003 and 2004.

Animal activists from Uist Hedgehog Rescue have been offering �20 for every live animal they are given.

SNH wants to cull the animals because of the threat they say they pose to important species of ground nesting birds - whose eggs they eat.