Hedgehog Facts
What’s in a name?
The Latin name for the European hedgehog is Erinaceus Europaeus, however they have a variety of regional names and these include: Hedgepig, Urchin, Furze-pig and Grainneog.
Characteristics
Hedgehogs are nocturnal, so it is unusual to see them out during the day, although over the summer months they are forced to come out at dusk and dawn during daylight as the days are that much longer. If you see a hedgehog out during the middle of the day, there’s something wrong and it will need picking up straight away - see our 'Found a hedgehog' page.
An adult hedgehog can weigh anything between 500g to 2kg. Hoglets normally weigh between 120g to 150g when weaned and must reach 600g by autumn to survive hibernation.
Hedgehogs do have quite long legs (which are hidden) so this does enable them to run quite fast (around 6 mph) and the first time you see their legs you may be surprised at just how long they are.
Hedgehogs are good swimmers and have been known to swim across quite wide rivers and are quite good climbers. If you have a pond in your garden and frequent hedgehog visitors, please ensure your pond has a sloped edge or steps/a ramp for hedgehogs and other animals to be able to access the water to drink, but a lifesaver if they do fall in, so they have the ability to climb back out.
A hedgehog's unique self defence mechanism is being able to roll into a complete tight ball to protect themselves from harm. They do not have a 'fight or flight' response to danger, so rather than running away, they curl up in a ball. This can leave them vulnerable to some predators, strimmer injuries and abuse/cruelty.
Spines
Hedgehogs are covered in around 5,000 to 7,000 sharp hollow spines, which are each between 2cm to 3cm long. Spines are modified hairs made of keratin (just like our finger nails) and each one has a brown tip. They are lost throughout the year just as we lose our hair. The spines only cover the top half of a hog; the underneath is covered in course thick hair, which keeps them dry and warm.
Hedgehog spikes are great shock absorbers and can take a certain degree of impact if they get themselves stuck in uncovered drains, steep sided holes and ponds or swimming pools.
Territory
Hedgehogs love a bit of rough and tumble and a it of head butting when competing for food, however they are not territorial and many can share the same garden space, just ensure you keep putting out plenty of food and water for them.
Hedgehogs have a home range and will travel the same gardens and sometimes route each night. An average home range is between 10 to 50 hectares. Males tend to have a larger home range, so they have the chance to meet females and therefore father more offspring. On average a hedgehog can travel between two to three kilometres (one to two miles) per night looking for food. This is where they can end up having to cross busy roads and accidents can happen. If you and your neighbours all put food out in your gardens and open a hedgehog highway between fences, this will help keep hedgehogs safe.
Diet
A natural hedgehog diet is made up of beetles, caterpillars, earthworms and millipedes, they will eat all manner of garden invertebrates, including frogs/toads, small mammals and birds eggs. Contrary to popular belief their diet is NOT mainly slugs and snails – this is a myth, as hedgehogs will only turn to eating these when their natural food source is in short supply. Slugs and snails give hedgehogs parasites and lung worm, which is a killer for hedgehogs if not treated in time.
Breeding
Gestation is around 30 days and babies are born without spines, but they do have around 100 spine buds which emerge within hours of birth. By the time they leave the nest, they have around 300 spines which are just a good a defence as adult spines.
They are born with they’re eyes closed (these open when they are around 10 – 14 days) and are unable to curl up, making themselves very vulnerable for the first few weeks of life. A litter size can be a single hoglet (normally to a first time mum) to up to 5 hoglets! Sometimes a mum will give birth to more but some will die as mum will not be able to feed this number of babies successfully.
If a mum manages to raise her litter before winter sets in she may try to have another litter. This is where autumn born hoglets run into problems because they don't have sufficient time to reach hibernation weight. We see many autumn juveniles brought to the rescue in early winter as they are out during the day trying to feed, they won't survive without intervention.
Hibernation
During hibernation, a hedgehog's heart beat slows to about 20 beats per minute and their breathing is also slowed right down. Hibernation normally starts around October but this does depend on the weather, a temperature of around 4°C is ideal for hibernation. It can take up to half an hour for a hedgehog to wake from this very deep sleep, so they can be very vulnerable during times of flood as they will not be able to wake up quickly enough.
Hogs normally wake up around April time, although, if spring comes early they will emerge when the temperature starts to pick up. The nests they make during the winter months are known as ‘hibernacula’. See our page 'The hedgehog year' for more info.