The threat of death against thousands of hedgehogs off the west coast of Scotland has moved a step closer.

A mass extermination was proposed two months ago by Scottish Natural Heritage (SNH) in an attempt to preserve rare bird populations in the Western Isles.

After a public outcry the conservation agency ordered a stay of execution while it looked into the feasibility of moving them off the islands.

But SNH has now concluded that the proposal is impractical and the best way forward is to kill the hedgehogs.

They were introduced on the islands in 1974 and now number about 5,000.

'Devastating impact'

SNH said the animals were responsible for a significant decline in the breeding of waders because they eat the birds' eggs.

Last year, a study published in the scientific Journal of Applied Ecology suggested that hedgehogs were having a devastating impact on seabirds in the Outer Hebrides.

It had long been suspected that hedgehogs ate large quantities of seabirds' eggs on the grassland where they nest.

An experiment carried out on South Uist found that wading birds like the dunlin, lapwing, redshank and snipe had a better chance of breeding successfully if hedgehogs were excluded from certain areas.

Management methods

Various methods of managing the hedgehog population have been considered by SNH.

These included sterilisation and contraception, or capturing the animals and moving them to the mainland.

SNH said that if these proposals were to work, welfare workers would only have 10 days in the early season to capture the hedgehogs.

The agency said these were all impractical and has concluded that humanely killing them is the best way forward.