NZ firm's scheme to wipe out rats on Scottish island derided

A New Zealand company's plans to wipe out thousands of rats ravaging wildlife on a Scottish island - while other experts rescue native woodmice - "sounds like Disney on acid", the Scotsman newspaper says.

But the 250,000 ($651,000) eradication planned by Wildlife Management International is deadly serious.

Next month, it will send abseilers to the tiny island of Canna to lay 3500 bait stations along the island's sheer cliffs.

Brown rats have overrun the west coast island since they were accidentally introduced by ship about a century ago. The rodents are wiping out seabird colonies and pose a threat to Canna's mice.

Surveys have shown that between 1974 and 1998, the Manx shearwater bird population declined by 90 per cent. Now only a handful of pairs remain.

The Scotsman reported yesterday that while the problem was undoubtedly serious, the publicly funded solution - called Operation Canna Recovery - "borders on the bizarre".

Wildlife Management International was hired after it removed rabbits from the Atlantic island of Deserta Grande, near Madeira, goats from the Galapagos Islands and feral cats from Pitcairn in the Pacific.

Wildlife Management staff will lower themselves down cliffs 100m high to position warfarin-laced bait stations.

So that the island's native woodmice are not also wiped out, a breeding population of around 120 rodents will be captured and transported to the mainland, to be returned when the rat menace has been dealt with.

The rat cull is being funded by the European Union at a cost equivalent to almost $46,800 a head for each of Canna's 14 human residents.

Canna is the most remote of Scotland's "Small Isles" and lies to the south of Skye.

- NZPA