As humanely as possible, environmentalists, nature lovers and Squirrel Nutkin fans say. The debate over how to stem rampant grey squirrels (2.5 million in the British Isles) in a bid to save the reds (160,000 and dwindling) is whether humanely means trained marksmen and trappers or biological poisons and birth control.
Campaigners in the Lake District this week appealed to the National Park Authority to send local tenants on a grey culling spree to prevent the extinction of the red squirrels in Beatrix Potter's home village. But Jason Reynolds, red squirrel conservation officer for the Cumbria Wildlife Trust, says: "We'd like to see them captured in a live capture trap then humanely killed by a gun or a blow to the head - RSPCA-approved methods."
Doctor Peter Lurz, a squirrel expert at Newcastle University says death may not be the only option. "In terms of red-squirrel conservation, killing greys is only a temporary thing. Reds survive best in conifer blocks. What we've been trying to do is cultivate sustainable red populations where greys don't flourish. You don't have a conservation conflict; you diversify the species mix to give the reds the upper hand. It's a balancing act."
However, greys do spread lurgies to the reds, and where there's an epidemic, culling is the right option, he adds. Parapox virus kills squirrels in two weeks, causing lesions on their face, eyes, anus and gland areas. The virus is so powerful that treatments have so far proved fruitless with the animals usually dying from a secondary infection.
Another option is a contraceptive. However, trials of an immuno-contraceptive where the grey squirrel's immune system is compromised prompting infertility failed, says Lurz. But Reynolds still hopes this may be the way forward: "In Australia they are developing contraceptives for rabbits and foxes and we're keeping a close eye on that.
"But doing nothing isn't an option. If we were to do nothing in Cumbria you wouldn't see reds 10 years from now - in many areas you wouldn't see them five years from now. These are the woodlands where Beatrix Potter wrote Squirrel Nutkin."