Should we cull one species to save another?

Large mice are devastating rare birds on a tiny island, now moves are afoot to exterminate the rodents. But should conservation ever be about killing?Gough Island is about as remote a fragment of land as it is possible to find on a map. Its 91 square kilometres of uninhabited volcanic rock rise from the South Atlantic, 3,200km east of South America and 1,700 miles west of Cape Town. But even this apparently pristine home to 8 million seabirds has been reshaped by humanity. Nineteenth-century seal-hunters visiting the island inadvertently introduced a stowaway: the house mouse. In the years since, this innocuous-looking species, the island's only mammal, has become its top predator, rapidly evolving to twice its original size.This monster mouse now eats seabirds alive. Ornithologists first discovered chicks of the endangered Tristan albatross with gaping wounds in 2001. Nocturnal nest cameras revealed the reason: mice clambering in and gnawing and devouring the chicks. Worse, they could even eat adult birds. They also predated thecritically endangered Gough bunting, which is only found on the isolated island. An estimated 2 million fewer seabirds fledge each year because of the mouse. Continue reading...