Dormice: Myoxidae

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DORMICE: Myoxidae

EDIBLE DORMOUSE (Myoxus glis): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Dormice look a lot like squirrels or chipmunks. Their fur is thick and soft and most species have long, bushy tails. Their tails help them to balance. Species are different sizes, but their average head and body length falls into the range of 1.6 to 8 inches (4.1 to 20.3 centimeters), their tail length ranges from 1.5 to 6.5 inches (3.8 to 16.5 centimeters), and they weigh from 0.5 to 7 ounces (15 to 200 grams). They are nocturnal, active at night, so they have large eyes and sensitive vibrissae, stiff hairs that can be found near the nostrils or other parts of the face in many mammals. They can also hear very well. These traits help them to function at night. Dormice also live in trees, so they have pads on the soles of their feet and strong, short curved claws on their four front toes and five hind toes so that they can grab onto the trees. Both their legs and toes are short. They can also hang upside down from branches by turning their hind feet backwards and grabbing onto the branches.

GEOGRAPHIC RANGE

Dormice are found in Europe, Africa, central and western Asia, and Japan.

HABITAT

Dormice can be found in deciduous forests, woodlands, grasslands, gardens, parks, rocky areas, or scrub areas. Within these areas, they create nests where they rest during the day. These nests are built off of the ground in holes in trees, rocky crevices, abandoned burrows, building attics, or in wedges of tree branches. The nests are ball-shaped, and are made out of leaves, grass, moss, lichen, shredded bark, other plant pieces, and saliva. They are lined with hair or feathers.

DIET

Dormice are omnivores, they eat plants and animals. Most of the time, they get their food from the trees in which they live. In the early spring and early summer, they eat buds and tree flowers. In the summer, they eat insects, small rodents, and bird eggs. In the late summer and fall, they eat fruit, berries, seeds, and nuts. They also eat snails and young birds. The specific type of food that they eat depends on their lifestyles and living areas, which is different from species to species. They also eat a lot during the fall in order to build up a layer of body fat to live on when they hibernate, go into a resting state during the winter season.

BEHAVIOR AND REPRODUCTION

Dormice usually live in small groups where half are younger dormice. Families hibernate together during winter. Hibernation occurs for about seven months. During this time period, their body temperature drops and their breathing and heartbeat slows down. They curl into a ball, with their tail covering their mouth so that they lose the least amount of water. They may wake up during this period in order to eat stored food, but this does not happen frequently. This extended resting time helps the dormice survive when there are low temperatures and little food to be found. Hibernation ends around April, when the weather gets warmer. At that time, they eat a lot of food and begin their mating season.

Dormice usually are not protective of their territory, but this changes during the mating season, when males become aggressive about their territory. Males use calls to attract the females. Males mate with more than one female during the mating season. The females can give birth from May to October. They are pregnant for three to four weeks. They can have anywhere from two to ten babies in a litter, although four babies is an average. The mother gives birth in her nest, in a tree hollow, on a branch, or maybe even underground in a shelter. When the young are born, they are pink, blind, and weigh around 0.07 ounces (2 grams). They grow gray hair by the time they are seven days old. When they are eighteen days old, they can see and hear and have brown hair. They are soon able to go out and find food with their mothers. When they are four to six weeks old, they are ready to go off and live on their own, but they may stay with their mothers through the next hibernation period. At the end of their first hibernation, the young are around a year old, and are ready to mate that spring. Dormice can live up to six years.

DORMICE AND PEOPLE

Due to the fact that dormice store food in their bodies in the form of fat, humans use dormice as a food source. They typically run into humans when they are trying to find areas in which to hibernate. They may even enter human homes for this very purpose. They can cause problems for humans when they eat the fruit in orchards.

CONSERVATION STATUS

More than half of dormice species are at risk. Dormice are threatened by loss of habitat and climate change, which changes their habitats and causes temperature shifts. The World Conservation Union (IUCN) lists four dormice species as Endangered, facing a very high risk of extinction; four as Vulnerable, facing a high risk of extinction; and five as Near Threatened, not currently threatened, but could become so.

EDIBLE DORMOUSE (Myoxus glis): SPECIES ACCOUNT

Physical characteristics: Edible dormice are a silver-gray color with white or yellow undersides. They have black areas around their eyes. They look like squirrels. They have large, round ears, small eyes, and long, very bushy tails. They use the rough pads on their feet to climb trees. Their head and body length is 5 to 8 inches (13 to 20 centimeters), their tail length is 4 to 7 inches (10 to 18 centimeters), and their weight is 2.4 to 6.3 ounces (68 to 179 grams). They are the largest of all the dormice.

Geographic range: Edible dormice live in Europe, Iran, and Turkmenistan.

Habitat: Edible dormice can be found in deciduous and mixed forests, and fruit orchards. Within these areas, they build their nests in woodpecker holes, fake nest boxes, hollow trees, rocks, and barns. They use hairs and feathers to line their nests. If there is not enough food available in their living area, they will move elsewhere.

Diet: Edible dormice eat a lot. By the winter, their weight will be almost double the weight they were at the beginning of the summer. They will eat insects in the summer, since fruit and seeds are not ripe enough. Once fruit and seeds become suitable for eating, they will eat them, as well as nuts, acorns, berries, and buds. They are mostly herbivores, plant-eating, and only eat insects or small birds when they have no other choice.

Behavior and reproduction: Edible dormice can be very quick and can also jump more than 23 feet (7 meters) when going from tree to tree. The males are territorial and tough fighters during mating season, which goes from June until August. They will mark their territories by scent, so that other males know not to cross over into their areas. The males make a squeaking sound during mating season while they follow around the females, in hopes of attracting a mate. The females will only give birth once a year and the males help raise, clean, and protect the young. The families may stay with one another during the hibernation months. Edible dormice can make a variety of sounds, including clicks, whistles, and growling. These sounds can take on different meanings. If predators attack them, they can make their tails fall off as a form of defense—the predator keeps the tail, but the dormouse escapes.

Edible dormice and people: Edible dormice can serve as food to people. In some areas, they are even considered to be a delicacy. They can also cause damage to humans when they destroy fruit or vine crops. They may also be captured for their fur.

Conservation status: Edible dormice are listed as Near Threatened by The World Conservation Union (IUCN), meaning that the species is not threatened now, but could be in the near future. ∎

FOR MORE INFORMATION

Books:

Alderton, David. Rodents of the World. New York: Facts on File, Inc., 1996.

"Dormice" and "Fat Dormouse, or Edible Dormouse." In Walker's Mammals of the World, 6th ed. Vol. II. Baltimore: The Johns Hopkins University Press, 1999.

"Dormouse." In National Geographic Book of Mammals. Washington, DC: National Geographic Society, 1998.

"Edible Dormouse." In Smithsonian Handbooks: Mammals. New York: DK Publishing, 2002.

Macdonald, David, ed. The Encyclopedia of Mammals. Volume III. New York: Facts on File, Inc., 2001.