Colin Varndell tells us how our prickly friends are in massive decline in Somerset and further afield

Great British Life: It is estimated that numbers have fallen by more than 90 per cent since the 1950sIt is estimated that numbers have fallen by more than 90 per cent since the 1950s (Image: Archant)

In spite of the hedgehog being voted Britain's favourite wild mammal, this much loved, bug-munching animal is struggling to survive in Somerset and in Britain as a whole.

The hedgehog is the only spiny mammal native to Britain and Western Europe. It is strictly nocturnal, becoming active at dusk, and may wander up to two kilometres a night in search of food or a mate. Hedgehogs have poor eyesight, good hearing and sensitive noses, and are constantly sniffing and snuffling as they find their way about. These prickly, curious mammals feed mainly on invertebrates, especially earthworms, leatherjackets, ground beetles, caterpillars and some (but not all) slugs.

The hedgehog's body is covered with 6,000 to 7,000 stiff, sharply pointed spines, which have evolved for protection. When a hedgehog senses danger, it will roll up into a tight ball with its sharp spines pointing in different directions.

Although mating can occur at any time throughout the summer the peak time for 'the rut' is during the months of May and June. Hedgehogs usually produce one litter of hoglets per year, with an average litter size of four to five young. Hoglets are weaned after three and a half weeks and become independent at around seven weeks of age. It is possible for an adult female to produce a second litter, in late summer, but the prospects for these babies are grim. It is very unlikely that an autumn juvenile, becoming independent in October, will be able to lay down sufficient fat reserves to survive hibernation.

The decline in the hedgehog population in UK has been known for some time. Numbers have fallen from an estimated 30 million animals in the 1950s to less than one million today, representing a catastrophic loss of more than 90 per cent of the population.

Reasons for this downward trend in hedgehog numbers are many and complex, and no single reason is entirely to blame.

Fragmented habitats on a large scale caused by busy roads, increased traffic volume, railways and industrial development are partly to blame. But arable farming, where the landscape is drenched with molluscicides, insecticides and other poisonous pesticides is also one of the main reasons for the decline.

Hedgehogs have a liking for birds eggs which made them most unpopular with gamekeepers. Badgers have been blamed for the decline of the hedgehog, but this suggestion is not supported with scientific evidence.

Great British Life: During hibernation hedgehogs reduce their body temperatureDuring hibernation hedgehogs reduce their body temperature (Image: Archant)

Although there have been reports of hedgehogs occurring in rural Somerset, these accounts are rare, as hedgehogs have retreated from the countryside to take refuge in urban areas. But here they face new dangers: garden machinery especially strimmers, slug pellets, rodenticides, drowning in swimming pools or ponds and dogs.

Dog bites are some of the most frequently reported injuries to hedgehogs coming into rescue centres. It is in urban habitats where most dogs live, and many dog breeds will instinctively attack small wild animals.

It is in our gardens where hedgehogs are drinking in the last chance saloon. This is their last chance for survival and we can all help to make a difference to the plight of hedgehogs by making our gardens more hedgehog friendly.

Access to your garden is most important, give hedgehogs a way in by making a CD size hole in a solid fence or wall and they will forage for slugs, earwigs, snails and other bugs.

It is not essential to feed hedgehogs but offering water at all times is. Make a log pile in a shady corner, which will harbour invertebrates on which hedgehogs feed. In autumn, leaf litter is important to hedgehogs either as nesting material or for foraging in.

So, don't dispose of leaf litter. Either compost it or leave it in a pile somewhere for hedgehogs to find. Leave an area of garden unmown to allow invertebrates to thrive.

Avoid bonfires by making a dead hedge out of shrub prunings as this will create a mini habitat for insects, as well as for birds and hedgehogs. Make a hedgehog house and position it in a shady place.

The hedgehog problem has been caused by human activities. With hedgehogs living amongst us, facing dangers even more acute than those that drove them from the countryside, it is up to us as individuals to act now.

Hibernation

As temperatures drop in late autumn, food for hedgehogs becomes scarce, as invertebrates are inactive and hide away in egg or larvae form. Hedgehogs overcome this shortage of food by hibernating from November until the spring.

Hibernation should not be confused with sleep. Sleep is an every day essential condition, hibernation is not. Indeed, many hedgehogs in southern England with access to food throughout winter do not hibernate.

During hibernation hedgehogs reduce their body temperature from 30°C to as low as 5°C or less and at the same time their pulse drops from 200 beats per minute to less than 20 beats per minute and breathing becomes very spasmodic. Hedgehogs face new dangers during hibernation from drowning, attacks by predators, running out of fat reserves or being burned alive in bonfires.

If a bonfire is necessary, either build it and burn it on the same day, or move it entirely before igniting.