Wednesday 1 March 2017 15.30 GMT
Hit by a car. Savaged by a dog. Slashed by a strimmer. Burnt in a bonfire. Tangled in garden netting. Poisoned by slug pellets. Caught in a postman’s discarded rubber bands. Head stuck in a tin can. Tricked out of hibernation by increasingly unpredictable winter weather. Modern life, governed by humans, designs a multitude of ingenious ways for a hedgehog to die. It is no wonder that this treasured animal, a suburban garden fixture, which consistently tops favourite-species polls and is the source of many people’s first close encounter with a wild creature, is vanishing from Britain.
This disappearance is rapid, and recent. A survey of more than 2,600 people by BBC Gardeners’ World Magazine in February found that 51% of gardeners didn’t see a hedgehog at all last year, up from 48% in 2015. Barely one in 10 saw a hedgehog regularly. Scientific studies are unequivocal. Britain’s hedgehog population was calculated to be 1.55 million in 1995. Since the turn of the century it has declined by a third in urban areas and up to 75% in the countryside. A survey based on roadkill calculates that hedgehogs are declining by 3% each year. This exceeds the International Union for Conservation of Nature red list criteria, which identifies species at greatest conservation risk. Why are we obliterating hedgehogs? Will they become extinct? Or can we save them?
Ecologist and nature writer Hugh Warwick has a spiky beard, a hedgehog tattoo and a familiar tale of a broken relationship with these beasts. He had hedgehogs in his garden in east Oxford until suddenly, four years ago, they disappeared. “What happened four years ago to make the hedgehogs vanish? It’s actually what happened 40 years ago,” he says. “We ended up with an area that was too small for them to survive.”
For all the small accidents that can befall a hedgehog, its decline is driven by one big trend, according to Warwick: habitat fragmentation. Female hedgehogs roam an average of 1km every night in search of insects and earthworms; males an average of 2km. To maintain a minimum viable population of 32 individuals in ideal hedgehog habitat (something rather like suburban gardens) there must be 90 hectares of contiguous land – that’s nearly 1km/sq of good quality, connected land. “That’s bloody terrifying,” says Warwick. He lives on a 20-hectare housing estate adjoining a seven-hectare park, surrounded by three busy roads and a canalised ditch. Of course, a few hedgehog populations will defy scientific modelling, but once Warwick’s roads became busier and the hedgehogs became trapped within 27 hectares, they were doomed.