Hedgehog (Erinaceus europaeus)
The European hedgehog (Erinaceus europaeus: Linnaeus, 1758), or common hedgehog is a hedgehog species found in western Europe.
It is a generally common and widely distributed species that can survive across a wide range of habitat types.
It is a well-known species, and a favourite in European gardens, both for its endearing appearance and its preference for eating a range of garden pests.
While populations are currently stable across much of its range, it is thought to be declining severely in the UK.
The animal appears brownish with most of its body covered by up to 6,000 brown and white spines.
Leucistic, or ‘blonde’ hedgehogs occasionally occur. Such specimens are believed to have a pair of rare recessive genes, giving rise to their black eyes and creamy-coloured spines; however, they are not strictly speaking albino. They are extremely rare, except on North Ronaldsay and the Channel Island
of Alderney where around 25% of the population is thought to be blonde. True albino forms of the hedgehog do also occur infrequently.
This species is largely nocturnal. It has a hesitant gait, frequently stopping to smell the air. Unlike the smaller, warmer-climate species, the European hedgehog may hibernate in the winter. However, most wake at least once to move their nests. They are solitary in nature with mature males behaving aggressively towards each other. Occasionally a male and female may share a hibernating spot.
The European hedgehog is omnivorous, feeding mainly on invertebrates. Its diet includes slugs, earthworms, beetles, caterpillars and other insects.
The preferred arthropods are the millipedes Glomeris marginata and Tachypodoiulus niger as well as the ground beetle Carabus nemoralis.
It also eats grass snakes, vipers, frogs, fish, small rodents, young birds and birds’ eggs. Some fruits and mushrooms may supplement the diet.
The breeding season commences after hibernation. Pregnancies peak between May and July, though they have been recorded as late as September. Gestation is 31 to 35 days. The female alone raises the litter which typically numbers between four and six, though can range from two to ten. Studies have indicated that litter size may increase in more northern climes.
The young are born blind with a covering of small spines. By the time they are 36 hours old, the second, outer coat of spines begins to sprout.
By 11 days they can roll into a ball. Weaning occurs at four to six weeks of age.
Longevity and mortality
European hedgehogs may live to ten years of age, although the average life expectancy is three years. Starvation is the most common cause of death, usually occurring during hibernation. If alarmed, the animal will roll into a ball to protect itself.
Many potential predators are repelled by its spines, but predation does occur. Remains of hedgehogs have been found in the stomachs of European badgers (Meles meles), red foxes (Vulpes vulpes) and pine martens (Martes martes).
A large portion of these may be from hedgehog carcasses, especially road-kill.