A marked decline in the number of the UK's hedgehogs has led to wildlife experts to add them to the Biodiversity Action Plan for threatened species. In this week's Green Room, Hugh Warwick argues that we have become bad hosts to the once frequent garden visitor.
Hedgehogs are pretty robust critters. In some form or other they have been around since the beginning of mammals; early versions were nipping at the heels of the departing dinosaurs.
They have survived ice ages, outlasted mammoths and sabre-toothed tigers and even managed to form a symbiotic relationship with their arch-predator, humans.
So why do we suddenly have to worry about the plummeting number of hedgehogs in the UK?
Each year there is a slightly ironic research project to determine the population of animals, called Mammals on Roads. It uses volunteers to drive stretches of highways, counting the number of corpses along the roadsides.
Co-ordinated by the People's Trust for Endangered Species (PTES), it has obvious benefits as far as gathering data on hedgehogs is concerned.
By comparing year-on-year figures, this technique has revealed a staggering drop in hedgehog numbers. Over the UK as a whole there was a 20% decline, and in some regions, it was as big as 50%.
In response to this, the PTES and the British Hedgehog Preservation Society launched HogWatch.
Using some of the best brains in the business - namely Dr Paul Bright and his colleague Anouschka Hof from Royal Holloway, University of London - we set about trying to find answers to the problems presented by the road kill data; primarily, what was causing this dramatic decline?
The first part of the project was to build a map, employing a host of amateur naturalists.
Nearly 20,000 people answered our call for sightings, and more importantly absence of sightings, because in order to build a useful map we needed to know not just where the hedgehogs were, but also where they were not.
The great response confirmed the place of hedgehogs in the nation's affection. It also showed that there was an unexpected split down the country with more hedgehogs being seen in the east.
City limits
So what are the reasons for the decline? Although the project is only half way through, we are already beginning to get an idea as to some of the main causes. Principal among these is habitat fragmentation.
A happy hedgehog habitat is one in which there is just the right combination of shelter and food. Despite the defensive prickles, hogs do like to keep to the edges.
In fact their natural home is woodland edge - something that we have recreated in abundance - hedges. Or at least there used to be plenty of hedges until the lunatic fashion of ecological destruction took hold.
But here is an interesting thought. There used to be no hedges. When the UK was largely forest, hedgehogs would have had to make do with clearings for their favoured climes.
They must have loved it as agriculture set in and hedges became the norm. But nothing stays the same; when the hedge-killers did their worst, the hogs sought refuge in suburbia as their homes were grubbed up and the farmers were paid for the havoc they wreaked.
In suburbia, humanity had created hedgehog heaven, a network of green spaces, complete with cover and food.
This is one of the reasons why hedgehogs are so popular; they are like the perfect house guest. We know they are there, but they make no fuss; they also help out around the place, cleaning up the lettuce, chomping mini-beasts that infest our beds and borders.
So what is making our guests feel so unwelcome? The refuge of suburbia, sanctuary from the ecological desert that so much of our industrialised countryside has become, is also turning hostile. And this is one of the reasons why hedgehogs are in decline.
As the roads become busier, so they also become impassable. As developments get denser, the wildlife corridors vanish.
As the gardens get turned into extensions, either literally or through decking and patio heaters, more habitat is lost.
As we manicure our green space, nuking bugs and napalming weeds, we drive hedgehogs and their food out into a wilderness with little sign of comfort.
But it does not need to be like this; hedgehogs are important - we have proved this time and again.
The Environment Agency wants a new icon and the vote goes to the hedgehog. Whether it is greetings cards, tea-towels or cuddly toys, hedgehogs are everywhere.
So the hedgehogs can now help us to help them - if we realise the impact that our lifestyles are having on such a charismatic and well-loved beast, perhaps we can halt the out and out destruction of all that is green.
If you want hedgehogs in your garden or park, see that they have what they need: shelter and food. Learn about hedgehogs so that you can begin to think like them.
The essence of empathy is in that level of understanding. Start to try and appreciate your local area with the eyes, nose and ears of a hedgehog.
What are going to be the obstacles to a hedgehog haven? Then see if you can start to remove them.
Hugh Warwick is a freelance writer and ecologist. His book, The Hedgehog's Dilemma, will be published in October 2008
As part of the book, Hugh is collecting anecdotes about hedgehogs from all over the world. If you have had an interesting hedgehog story you would like to share, please email him at:
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Mon Apr 02, 2012 10:11 am