Erinaceus europaeuswestern European hedgehog

Geographic Range

Erinaceus europaeus (European hedgehog) is commonly found across Europe and into central Asia. Native to this region, it can be found from the Archipelago of the Azores and as far east as Khazakstan. It is commonly seen in northern Europe, as far as Scandinavia. While it is generally not found south of the Mediterranean Sea, it has been seen in Lebanon. Erinaceus europaeus is also found in New Zealand, where they were introduced in the late 1800s. (Bogdanov, et al., 2009; Brockie, 1959; Mathias, et al., 1998; "Division of Mammals Collections: Search "Erinaceus europaeus"", 2011)

Habitat

The European hedgehog is found in temperate fields, especially field edges and hedgerows. They prefer drier areas that are not thickly wooded and are occasionally found in scrub and sand dunes. European hedgehogs are commensal and are often found in home gardens, cemeteries, parks, agroecosystems, and other areas that provide appropriate places for hibernation. It commonly occupies elevations from sea level to 2400 m throughout its geographic range. (Beilby, 1791; Burton, 1969; Gaglio, et al., 2009; Hof and Bright, 2010; Johnston, 1903; Lawrence and Brown, 1973; Southern, 1964)

  • Range elevation
    0 to 2400 m
    0.00 to 7874.02 ft

Physical Description

The European hedgehog is a small, round animal with short legs that raise it about 1 inch above the ground. It is plantigrade and has 5 well developed pads and claws on each foot. The first and fifth toes are smaller and weaker than the second, third, and fourth toes. Its coat is white and brown and consists of 3/4 to 1 inch spines, arranged in a radiating pattern, that cover all but its cheeks, throat, stomach, and limbs. Areas not covered in spines are covered in a coarse hair that is yellow-brown in color, though white hedgehogs have been seen. It has an elongated, conical head and snout, a small braincase, a short neck and tail, and well developed eyes and ears. The length of its body ranges from 135 to 265 mm, and males are usually slightly larger than females. The tail is about 20 mm long. (Burton, 1969; Forrest, 1899; Gordon, 1904; Johnston, 1903; Kindahl, 1959; Lawrence and Brown, 1973; Rondinini, 2007; Southern, 1964; Step, 1921; Walker, 1968)

The spines covering the European hedgehog's body have white tips and bases and are covered with alternating brown and black bands. They are hollow and have longitudinal grooves, which decrease their weight. Spines are made of keratin and are attached to the skin in a similar way to hair. Each spine grows from a follicle in the skin that is attached to a small muscle (arrector pili) that is used for piloerection. When a hedgehog rolls into a ball, all of the spines can be erected simultaneously, which is made possible by the panniculus carnosis, a sheet of muscle that covers its back. An adult hedgehog usually has around 5,000 spines covering its body. (Burton, 1969; Forrest, 1899; Gordon, 1904; Johnston, 1903; Kindahl, 1959; Lawrence and Brown, 1973; Rondinini, 2007; Southern, 1964; Step, 1921; Walker, 1968)

Erinaceus europaeus has lacteal and permanent teeth. The permanent dentition features widely space upper incisors such that the lower incisors fit between them. The dental formula for E. europaeus is 3/2, 1/1, 2/3, 3/3. (Burton, 1969; Forrest, 1899; Gordon, 1904; Johnston, 1903; Kindahl, 1959; Lawrence and Brown, 1973; Rondinini, 2007; Southern, 1964; Step, 1921; Walker, 1968)

  • Sexual Dimorphism
  • male larger
  • Range mass
    800 to 1200 g
    28.19 to 42.29 oz
  • Range length
    135 to 165 mm
    5.31 to 6.50 in
  • Average basal metabolic rate
    2.434 W
    AnAge

Reproduction

European hedgehogs are solitary and non-territorial. They begin the mating process when a male encounters a female, at which time the male encircles the female while she lowers her head and makes a variety snorts, grunts, and hisses. If the male is successful in courting the female, he attempts to mount her several times. After numerous copulations, the male leaves the female, and does not provide any parental care to his offspring. He continues to roam alone and attempts to mate with other females until he begins preparing for hibernation. Males and females have multiple mates each season. (Burton, 1969; Hof and Bright, 2010; Rondinini, 2007; Southern, 1964; Walker, 1968)

Erinaceus europaeus begins mating in late spring (April or May) when the the animal emerges from hibernation. Males, which emerge 3 to 4 weeks before females, expand their home range during mating season to increase chances of finding a mate. When a male finds a mate, he circles her while she lowers her nose and becomes audibly defensive. The male may circle for several hours, making several attempts to mount. If the female continually rejects the male, he eventually leaves to find a receptive female. If she accepts him, she flattens her spines and lowers herself to the ground, which gives the male better access. To copulate, a male climbs onto a female's back and uses his teeth to hold onto her shoulder. Gestation last for about 35 days. Females give birth to four to six offspring per litter, and often have two litters per year. The second litter, which is born later in the year, has a reduced chance of surviving winter. New borns are about 3 inches long and weigh 0.3 to 0.9 oz. At birth, E. europaeus does not appear to have spines, which are concealed beneath their fluid filled skin. 24 hours after birth, the fluid is absorbed and the spines are revealed, and, 2 to 3 days later, the young’s musculature is developed enough to allow it to hold the spines erect. These white adolescent spines are replaced by darker spines after about 1.5 days. Pigmented adult spines replace the first two coats after about 2 to 3 weeks, at which time young begin to open their eyes and learn how to roll into a ball. Young are weaned by 4 to 6 weeks old, after which they become independent of parental care, and are able to mate by about 1 year. (Bunnell, 2009; Burton, 1969; Johnston, 1903; Rondinini, 2007; Southern, 1964; de Magalhaes and Costa, 2009)

  • Breeding interval
    Hedgehogs breed seasonally, and can have up to two litters per season
  • Breeding season
    April to September
  • Range number of offspring
    1 to 9
  • Average number of offspring
    1.5
    AnAge
  • Range gestation period
    30 to 49 days
  • Range weaning age
    4 to 6 weeks
  • Range time to independence
    4 to 6 weeks
  • Average age at sexual or reproductive maturity (female)
    253 days
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    253 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    253 days
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    253 days
    AnAge

Weaning usually occurs 6 weeks after birth, at which time young European hedhogs begin venturing out of the nest with their mother. They begin to forage and create an overwintering nest on their own. Most individuals are sexually mature by the first spring after their born. (Bunnell, 2009; Rondinini, 2007)

  • Parental Investment
  • precocial
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female

Lifespan/Longevity

In the wild, European hedgehogs can live up to six years. In captivity, they can live as many as ten years. (de Magalhaes and Costa, 2009)

  • Range lifespan
    Status: wild
    8 (high) years
  • Range lifespan
    Status: captivity
    11.7 (high) years
  • Typical lifespan
    Status: wild
    6 (high) years
  • Typical lifespan
    Status: captivity
    10 (high) years

Behavior

Erinaceus europaeus is nocturnal, predominantly solitary, and non-territorial. It meets intentionally with others only during the mating season, but a social hierarchy may exist such that mature females have dominance over prime feeding sites. Hedgehogs have relatively large home ranges that are difficult to defend, and as such, they roam freely during the night. They tend to rest during the day in shallow nests made of twigs, leaves, grass, pine needles, and other foliage. Each nest is utilized by more than one individual, but never at the same time, and hedgehogs may also share urine sites. Aggressive interactions have not been observed between individuals. (Burton, 1969; Forrest, 1899; Jones and Digger, 2009; Rondinini, 2007; Southern, 1964; Walker, 1968)

Erinaceus europaeus travels at an average speed of 110 to 220 yards per hour. They are successful swimmers and climbers and are able to squeeze through tight spaces. When threatened, hedgehogs curl into a ball, exposing their sharp spines while protecting their vulnerable underbelly and face. However, hedgehogs prefer to avoid contact with predators by living in areas devoid of predator odors despite an increase in hedgehog population density. (Burton, 1969; Forrest, 1899; Jones and Digger, 2009; Rondinini, 2007; Southern, 1964; Walker, 1968)

As day length decreases, European hedgehog begin looking for sufficiently insulated hibernation nests. In colder areas, hibernation usually begins in October and lasts until April; in warmer areas, hedgehogs may only hibernate during the coldest of winters. Hedgehogs survive the cold temperatures by storing fat to be used as insulation and as an energy reserve to wake up when necessary. These periodic breaks in hibernation occur every 1 to 2 weeks and last for 1 to 2 days, during which hedgehogs forage for food and urinate. Provided sufficient resources, captive hedgehogs do not hibernate.

  • Range territory size
    0.04856 to 0.4046 km^2
  • Average territory size
    0.1214 km^2

Home Range

European hedgehogs require large foraging areas (often no more than 100 acres) due to inconsistent and unreliable distribution of food. When food is more abundant, such as in home gardens or other agroecosystems, European hedgehogs may have a home range as small as 12 to 25 acres. Males generally have home ranges up to twice the size the female’s home range. (Jones and Digger, 2009; Rondinini, 2007)

Communication and Perception

European hedgehogs are not particularly noisy, and make mostly grunting, snorting, and hoarse squeaking sounds. Adults are vocal during mating, while feeding, and occasionally when captured. Young may squeak and whistle while in the nest. Due to its nocturnal behavior, European hedgehogs rely heavily on their senses of smell and hearing. In addition to having a well developed sense of smell, they, like many mammals, have a Jacobson's organ in their palate. The organ may have a role in social behavior as both male and female hedgehogs have a variety of scent glands. While the mechanisms of hearing in E. europaeus have not been well studied, research on a related species, the Long-eared hedgehog, has found it capable of processing high-frequency sounds up to 45kHz. (Burton, 1969; Forrest, 1899; Johnston, 1903; Rondinini, 2007; Southern, 1964; Step, 1921)

Food Habits

European hedgehogs are omnivorous, but predominantly feed on insects. They favor beetles, ants, bees, wasps, earwigs, butterflies and moths. Hedgehogs may also eat cockroaches, crickets, grasshoppers, snails, eggs, lizards, snakes, frogs, small rodents, and carrion. (Burton, 1969; Gaglio, et al., 2009; Gordon, 1904; Johnston, 1903; Jones, et al., 2005; Rondinini, 2007; Southern, 1964; Step, 1921)

  • Animal Foods
  • birds
  • mammals
  • amphibians
  • reptiles
  • eggs
  • carrion
  • insects
  • terrestrial non-insect arthropods
  • terrestrial worms
  • Plant Foods
  • seeds, grains, and nuts
  • fruit

Predation

Predators of the Erinaceus europaeus include dogs, foxes, snakes, large owls, and badgers. To protect themselves, hedgehogs have the ability to curl into a defensive ball that exposes only erected spines. In order to form into a ball, they constriction the panniculus carnosus muscle. When this occurs, the muscles associated with each spine contract, leaving all of the hedgehog’s spines erect. Some predators, such as badgers and foxes, may be able to gain access to the hedgehog by wedging their noses into the crease where the top and bottom of the spiny coat meet. Predators have also been known to drop a balled hedgehog from a height so as to shock or injure the hedgehog long enough for them to take advantage of its exposed underbelly. (Hof and Bright, 2010; Johnston, 1903; Rondinini, 2007; Vermeulen, et al., 2009)

Ecosystem Roles

Hedgehogs are omnivorous, feeding on a wide variety of animal (especially insect) and plant material. They may help control insect pest populations in some areas. Hedgehogs are hosts to a variety of parasites including nematodes (Crenosoma striatum, Eucoleus aerophilus, Capillaria erinacei, Capillaria ovoreticulata and Capillaria spp.), trematodes (Brachylaemus erinacei), acanthocephalans (Oliganthorhynchus erinacei), ticks (Ixodes hexagonus), and fleas (Archeopsylla erinacei). (Gaglio, et al., 2009; Hof and Bright, 2010)

Commensal/Parasitic Species
  • Ixodes hexagonus
  • Crenosoma striatum
  • Eucoleus aerophilus
  • Capillaria erinacei
  • Capillaria ovoreticulata
  • Capillaria
  • Brachylaemus erinacei
  • Oliganthorhynchus erinacei
  • Archeopsylla erinacei

Economic Importance for Humans: Positive

Hedgehogs are routinely kept as pets, but the European hedgehog is forbidden as a pet in Europe. Due to their broad diet, hedgehogs may help control insect pests. They have proven useful for the study of numerous diseases including foot and mouth disease, yellow fever, and influenza. Their hair and spines are useful in assessing for environmental pollutants including arsenic, silver, cadmium, lead, cobalt, and Persistant Organic Pollutants (POPs). Traditional remedies have incorporated the blood, entrails, or ashes of European hedgehogs, and some rituals involving hedgehogs have been used to cure baldness and predict the weather. Ancient Romans raised hedgehogs for their meat, and they used parts of the hedgehog, especially their spiny coat, for training work animals. (Burton, 1969; D'Havé, et al., 2005; D'Havé, et al., 2006; Hof and Bright, 2010; Southern, 1964; Vermeulen, et al., 2009)

  • Positive Impacts
  • pet trade
  • food
  • body parts are source of valuable material
  • research and education
  • controls pest population

Economic Importance for Humans: Negative

Hedgehogs are potential vectors for a number of parasites and pathogens including ticks, fleas, mites, ringworm, influenza, yellow fever, Salmonella enteritidis, leptospirosis, and foot and mouth disease. (Burton, 1969; Gaglio, et al., 2009; Southern, 1964)

Conservation Status

Formerly a common sight in the UK, local populations of Erinaceus europaeus appear to be rapidly declining. Despite this, E. europaeus is listed as a species of least concern on the IUCN's Red List of Threatened Species. The reasons for its decline are unclear, however, E. europaeus has been included in the UK Biodiversity Action Plan. (Hof and Bright, 2010)

Contributors

Colin Roberts (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, John Berini (editor), Animal Diversity Web Staff.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carrion

flesh of dead animals.

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

food

A substance that provides both nutrients and energy to a living thing.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

nomadic

generally wanders from place to place, usually within a well-defined range.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

young precocial

young are relatively well-developed when born

References

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