Hedgehogs are the only spiny mammal in Britain, they were introduced to Jersey in the middle of the 19th century, around the same time as red squirrels. They are a very ancient animal and have been around in their present form for about 15 million years.
When are they active?
They are nocturnal, which means they are normally only out of their nests when it is dusk or dark, but in summer when the nights are short, you may see one in the evening or early morning when it is light, because there are not enough hours of darkness for it to find enough food. Females who are about to or have just given birth are often out foraging when it is still light in mid-summer - as long as the hedgehog is active and looks well and uninjured please leave her alone to go back to her family. You can offer her a dish of water and some cat or dog food which will be very welcome, especially in dry weather.
What do they eat?
Hedgehogs are insectivores and will eat a wide variety of insects and invertebrates in your garden, which is why they have been called “the gardener’s friend”. They do no harm in the garden.
Please garden organically
They are at risk from slug pellets, insecticides and other garden chemicals and so we ask people not to use any harmful pesticides in their gardens.
They have no natural predators in Jersey, as there are no badgers or foxes on the Island, but there are still many hazards for them to face, most of them caused by humans.
Rats, feral ferrets and dogs may attack them and even kill them.
Cats will only pose a threat to very young hedgehogs before they are independent of mother.
The breeding season in Jersey runs from May to October, males take no part in family life, once they have mated they disappear into the night to find the next female. Gestation is about 35 days, mother hedgehogs suckle their babies or hoglets for 4-6 weeks after they are born, feeding them on their very rich milk, which makes them double their birth weight in the first week of life. There can be as many as 8 in a litter but 4 or 5 is a more usual number. At birth hoglets weigh anything from 7-25g and when they leave mother at about two months old, they weigh about 250g.
By about 9 or 10 days old they start to roll up - or try to!
At two weeks old the eyes start to open, the teeth do not erupt until the third week. By the time they are four weeks old they look like miniature adults. This is the age when they follow Mum from the nest and learn to forage for food.
Rescuing lost hoglets:
Young hedgehogs sometimes get lost or trapped and are found by kind people in the morning who contact us and we take care of them until they are old enough to be completely independent. If you should find a baby hedgehog on its own out in the open in the day time, please do take action, because if left, flies will come along and lay their eyes on it and then maggots will hatch. If you live in Jersey, phone us on 01534 734340, if you are out of the island, please contact your local vet or nearest hedgehog carer. The British Hedgehog Preservation Society has a list of UK carers please phone 01584 890 801 they have a 24 hour answerphone service.
Nest building: A hibernating nest or hibernaculum is made of dry leaves and grass, it takes several nights to build, it has to be water- and weatherproof, so that the inside temperature remains constant, whatever the weather does outside. The hedgehog carries leaves and grass in its mouth until it has made a big pile, then it goes round and round inside, weaving a sturdy nest with its spines. The nest is built under brambles or some other sort of support to keep it in shape. Hedgehogs will make several of these nests during the autumn in preparation for winter.
During the winter when insects and other invertebrates are hard to find, hedgehogs go into hibernation to save energy, which means they slow their whole body right down to an absolute minimum, their breathing, heart rate and metabolic rate just tick over.
What does a hibernating hedgehog look like?
If you accidentally disturbed a hibernating hedgehog, you might think it was dead, it would feel stone cold and would be in a tight ball, and you would have to wait some time before you could see it breathe. If you gently touched its spines, they might flinch, so you would know it was alive. But if it was in really deep hibernation, you might get no clue at all whether it was alive or dead.
What should you do if you accidentally disturb a hibernating hedgehog?
As long as it is a nice round shape and weighs more than 450g you should gently put it back where you found it, covering it over with all the nest material you have disturbed and it will wake up in its own time and find another nest. If it is lighter than 450g or looks thin with a pointy bum, please put it in a box and contact us or your local hedgehog hospital so that it can be slowly woken up and cared for until it reaches a safe weight to survive the rest of the winter. An adult hedgehog weighing 450g is going to be very thin whereas a juvenile might be OK - it is difficult to give a specific weight.
The hog on the left is thin and in need of help the one on the right is nice and round
Should you be worried if you see a hedgehog out at night in the winter?
It is quite usual to see hedgehogs about at night during the winter months, especially in mild weather, they don’t hibernate for the whole time, they wake up in their nests every 7-10 days, and may or may not come out for something to eat and drink. It is only if you see one out and about during the daytime or a small one weighing less than 450g after dark that you should be concerned and seek advice and help.
How do they survive the winter?
They have two types of fat, white fat to live off and special lobes of brown fat, which act like booster fuel to restart their metabolism when they wake up. So during the autumn they need to put on enough body fat to keep them going through the winter, they lose about a quarter of their body weight during hibernation. This is why youngsters in their first year are especially vulnerable, and many do not survive their first winter in the wild.
What is the minimum weight they should be to survive? ````
Juveniles need to weigh 450g by the end of November or when the cold weather comes, if they are to stand a good chance of surviving the winter in the wild. If people find underweight autumn juveniles, we try to help them, fattening them up and then releasing them in a mild spell or perhaps waiting until Spring.
If you would like to learn more about hedgehogs and other local environmental issues please visit the other sites please see our links page.