Tag Archives: Hibernation

Horay for hedgehogs

I’m not the only one emerging from hibernation at the moment. A couple of days ago we finally saw our first hedgehog of the year. It’s been a long time coming, as we’ve been finding plenty of ‘signs’ of hedgehogs for a few weeks. 

We’ve been leaving out food for them, but whereas in previous years we could leave the bowl in the open, I think we need to build a hedgehog feeding station to keep out the neighbours’ kittens this year. 

It’s so nice to see the hedgehogs again. I hope the dormice will follow suit for our April box check. 


Fascinating wildlife fact #12: dormice spend three quarters of their life asleep

Not only do dormice hibernate for around half the year, they also spend a large part of early summer in a state called ‘torpor’. Torpor is somewhere between sleep and hibernation, and helps them save energy on cooler days. They also sleep through most of the day, even at the height of summer.

torpid dormouse
Torpid dormouse


NB. for pedants - hibernation is different from sleep, as is torpor. But it's not such as punchy fact if I try to explain that in the headline.

How to build a hedgehog box

You’ve probably heard that hedgehogs are having a tough time these days. Numbers in Britain have fallen by around a third in the last 10 years. So they need all the help they can get.

If you have a garden, there’s lots you can do to make it hedgehog friendly. Leaving gaps in your fence, having a variety of lengths of grass and good dense undergrowth, and avoiding slug pellets all help. They also need places to sleep in summer, and hibernate in winter.

Open compost heaps and piles of dead wood are good, easy ways to provide hedgehog hotels. When we had to get our fence repaired after the winter storms the fencers found a hedgehog hibernating in our compost heap.

When we found out that we had regular spikey visitors to our garden, we decided to offer them some luxury accommodation, in the form of a hedgehog box, to encourage them to spend even more time eating our garden bugs.

If you’ve spotted hedgehog boxes for sale, you’ll probably have noticed that they are very expensive. A good wooden one could cost you £50. We had some spare wood, so decided to save some cash and build one ourselves.

The British Hedgehog Preservation Society have an excellent leaflet on how to build hedgehog boxes. It includes several designs, ranging from a quick and easy ‘council tax band A’ one made from a sturdy cardboard box, to a luxury ‘band H’ one suitable for the David Beckham of hedgehogs.  Living in Surrey, home of most of the Chelsea squad, we had to go for that one.

Besides the wood and screws, it also required a small length of hose for ventilation, and some plastic sheeting to keep the water out (both of which were easily obtained from our local hardware shop – the type of place you could buy four candles from). We also bought some hay from the pet shop for the hogs to use as bedding.

Neither Dr C nor I are DIY experts, but the instructions were clear and it was straightforward to build. We made it in a (not too long) day.

Hedgehog box in situ, before burying
Hedgehog box in situ, before burying

We sited in the shade next to the fence and a small hedge. We then built a little entrance tunnel from leftover bricks, and covered the whole thing in some earth and greenery.

Finished hedgehog box in situ
Finished hedgehog box in situ

We’ve evidence that hedgehogs have used it, although I don’t know how regularly. I plan to install a camera in it to find out what goes on in there.


I’m writing this sat cosily in front of a fire, but feeling sorry for myself as I have a cold. It’s been a hectic few weeks, out every evening for one thing or another, and lots happening at work. Right now, I can’t help envying the hedgehog who is hibernating in our hogitat. I wish I could hibernate.

Hibernation is a very clever strategy for getting through the winter, when there’s not much food around for some animals. Comparing it to a long, deep sleep fails to do justice to it. The body temperature of hibernating animals drops to match its surroundings (but always kept above 1 degree C so it does not freeze). Their heart rate slows, and they can go almost an hour between short bursts of breathing. This reduces their energy consumption by around 90%.

Hibernating animals rely of fat supplies built up during summer and autumn. By now nearly all hedgehogs and dormice will be hibernating. Those who aren’t are likely to be underweight individuals looking for more food before they hibernate. While hibernation uses much less energy than being active, they still need enough fat to keep their bodies ticking over, and also to help them wake up.

On warmer winter days hibernating animals might wake from hibernation, and may even stir to find food or drink. But each time the animal wakes it uses up some of its precious fat reserves, so mild or variable winters are not good for hibernating creatures.

Hibernation is not without its risks. It can take hibernating animals several hours to wake, so they cannot respond quickly to threats like predators or floods. A considerable proportion of hibernating animals do not make it through the winter, not having enough fat reserves. But then winter does kill off a lot of more active animals as well.

Of UK mammals, only bats, dormice and hedgehogs properly hibernate. Other mammals, such as badgers, will reduce their activity, and stay snuggled down sleeping in their setts, but not shut down so much. Given the risks of hibernation, maybe I’d be better off imitating the badger instead… If you don’t see me for a while, you’ll know what I’m up to!

Hedgehogs and bonfires


Piles of logs make an excellent home for many animals, including hedgehogs. They are a great way of attracting wildlife to your garden. Unfortunately, if you’re a hedgehog it’s rather difficult to distinguish between a nice safe log-pile to hibernate in, and one that is about to become a bonfire. If you’re having a bonfire this year, build it at the last minute or check it thoroughly before lighting to make sure no hedgehogs get a nasty surprise.

And do consider creating a permanent log pile in a quiet corner.

Enjoy the fireworks!