HARES AND RABBITS: Leporidae

PHYSICAL CHARACTERISTICS

Adult rabbits and hares have a body length of 10 to 28 inches (25.4 to 71.1 centimeters) and weigh 14 ounces to 15.3 pounds (400 grams to 7 kilograms). They have short, furry tails and ear sizes vary greatly and generally are shorter in rabbits and longer in hares. The main exceptions are the rabbit breeds known as lops, which have long, floppy ears. Females are generally larger than males. Hares generally are larger than rabbits and have black-tipped ears.

Rabbits and hares usually have thick, soft fur that comes in a wide spectrum of colors, shades, and combinations, including black, white, brown, beige, tan, blue, orange, red, pink, cream, lilac, silver, and lavender.

Hares and rabbits have eyes set high on their head, looking sideways, giving them a wide field of vision. They have weak but flexible necks, allowing them to turn their heads with a wide range of motion. They have a single opening to pass both urine and feces. They also have a specialized part of their large intestine, called the cecum (SEE-kum), which acts as a fermentation chamber that aids in digestion of grasses.

GEOGRAPHIC RANGE

Hares and rabbits are found on every continent except Antarctica. They are native to every continent they are found on, except Australia where they were introduced.

HABITAT

Hares live in arctic tundra, steppes, wetlands, forests, and deserts. Rabbits live in pine and deciduous forests, desert, mountainous areas, scrubland, tropical rainforest, near rivers and streams, rocky outcroppings, grasslands, and areas of dense brush or other low-lying vegetation.

DIET

Hares and rabbits are herbivores, meaning they are plant-eaters. With a primary diet of grasses and herbs but also will feed on fruit, seeds, leaves, shoots, and bark.

BEHAVIOR AND REPRODUCTION

Rabbits and hares have several types of social structure. Most rabbits and hares in the wild live solitary lives, although they will often graze together, and are not territorial. The European rabbit is very social. It lives in "warrens," groups of six to twelve adults controlled by a dominant male. The warren consists of a maze of burrows and chambers.

Rabbits breed throughout the year depending upon the climate, with spring and summer being the general breeding seasons in the wild. Females have multiple litters per year with litter sizes of two to eight babies on average, although it can be as high as 15 babies. The gestation period, the length of time the mother carries her babies in the womb, is twenty-five to fifty days, with the longer periods occurring in hares.

HARES AND RABBITS AND PEOPLE

Rabbits and hares are hunted worldwide for sport. They are both hunted and raised commercially for their meat and fur. Several species are used extensively in laboratories. Rabbits are also raised as pets.

TEN-YEAR CYCLE

A unusual and striking feature of the snowshoe hare is its ten-year cycle of population increase and decline. The number of litters per year and the number of young per litter is higher for about three years, declines in the next three or four years, and then drops significantly in the last three or four years of the cycle. Why this happens is not completely understood by scientists but they believe it is caused by one or more factors, such as food availability, predation, and social interactions.

CONSERVATION STATUS

Two species are listed by the World Conservation Union (IUCN) as Critically Endangered, facing an extremely high risk of extinction; eight species are listed as Endangered, facing a very high risk of extinction; four species are listed as Vulnerable, facing a high risk of extinction; and six species are listed as Near Threatened, not currently threatened, but could become so.

The primary reasons for declining populations of hares and rabbits are loss of habitat, disease, especially the pox virus myxomatosis (mix-oh-mah-TOE-sus), and conversion of habitats to agricultural use by humans.

In the United States, the pygmy rabbit has experienced a sudden decline that has caught even conservation groups off-guard. Although it is listed by IUCN as Near Threatened, it is listed as an endangered species by the state of Washington. Wildlife officials estimate that as of 2003, only thirty pygmy rabbits existed in the wild in the state's Columbia Basin. The decline is blamed on loss of sagebrush, its primary habitat. Mexico's volcano rabbit is found only on the slopes of four volcanoes near Mexico City. Its population is estimated at about 1,000 and declining due to encroachment on its habitat by human development. The Davis Mountains cottontail is not listed by the IUCN but Portland (Oregon) State University biologist Luis Ruedas has tried unsuccessfully to get the state of Texas to list it as endangered. It is found only in a small mountain range in Texas.

SNOWSHOE HARE (Lepus americanus): SPECIES ACCOUNTS

Physical characteristics: Snowshoe hares range in length from 16.5 to 20.7 inches (41.3 to 51.8 centimeters). They weigh from 3.12 to 3.4 pounds (1.4 to 1.56 kilograms). Females are slightly larger than males.

In the summer, their fur is rust or gray-brown with a black line running down their mid-back, cream colored on the sides of their lower body, and a white underside. Their face and legs are cinnamon colored. Their ears are brown with black tips and white or cream edges. During the winter, they turn white except for their black eyelids and black ear tips. The bottom of their paws are covered with dense fur, hence the name snowshoe hare.

Geographic range: Snowshoe hares are found throughout Canada and the northern United States, including Alaska, and the Rocky Mountains as far south as northern New Mexico.

Habitat: Snowshoe hares live in open fields, swampy areas, riverside thickets, coniferous forests, including subarctic coniferous forests located south of tundra, and tundra.

Diet: Snowshoe hares have a varied diet. In the summer, it includes grasses, flowers, wild strawberry plants and fruit, dandelion, clover, horsetails, and new growth of aspen, birch, and willow trees. In the winter, they forage, search, for buds, twigs, bark, and evergreens.

Behavior and reproduction: Snowshoe hares are generally solitary but large populations often live within a small geographic area. They are nocturnal, meaning they are most active at night, and crepuscular (kri-PUS-kyuh-lur), meaning they are also active during dawn and twilight.

When snowshoe hares sense a predator is near, they often stand completely still, blending in with their surroundings. They are also fast runners, and have been clocked at speeds of up to 27 miles (43 kilometers) per hour. They can cover 10 feet (3 meters) in a single leap. They have acute hearing and are capable swimmers, able to swim across small lakes and rivers, usually to escape predators.

Snowshoe hares breed from mid-March through August. Females can have up to four litters per season, with litter sizes ranging from one to eight babies. The average litter size is two to four babies. The gestation period, the time the females carry the young in their womb, is thirty-six days. The young reach sexual maturity, ability to reproduce, at one year of age.

Snowshoe hares and people: The snowshoe hare is widely hunted by humans for its meat and fur.

Conservation status: The snowshoe hare is not listed as threatened by the IUCN. They are common throughout their range and populations seem to be remaining steady. ∎

MOUNTAIN HARE (Lepus timidus): SPECIES ACCOUNTS

Physical characteristics: The mountain hare is medium-sized with short ears and hind legs. It has a body length of 18 to 24 inches (46 to 61 centimeters) and weighs 2.2 to 8.8 pounds (1 to 4 kilograms.) Their fur changes from brown in the summer to white in the winter.

Geographic range: Mountain hares are found in Arctic and adjacent temperate areas of northern Europe and Asia, from Ireland to eastern Siberia.

Habitat: Mountain hares live in tundra, subarctic coniferous forests, mixed coniferous and deciduous forests, and transitional zones with open clearings, swamps, and river valleys.

Diet: Mountain hares are herbivores, meaning they are plant-eaters. Their diet varies by habitat and season. In the summer, forest dwellers eat mostly grasses, leaves, and twigs. Tundra inhabitants eat primarily alpine plants along with grasses, lichen, and bark. In the winter, heather is the main food source.

Behavior and reproduction: The mountain hare is primarily solitary and is seen in groups only when breeding. The breeding season is from January to September. Females have one or two litters per year, with a litter size of one to four babies. If there is an early spring, females can have up to three litters. The gestation period, the time the female carries the young in her womb, is forty-seven to fifty-four days.

Mountain hares and people: Hunted by humans for its meat and fur.

Conservation status: The mountain hare is not considered threatened by the IUCN. ∎

DESERT COTTONTAIL (Sylvilagus audubonii): SPECIES ACCOUNTS

Physical characteristics: A larger cottontail with large ears. Head and body length of 14 to 15 inches (37 to 40 centimeters) and its weight is 26.5 to 44 ounces (750 to 1,250 grams).

Geographic range: Desert cottontails are found in North America, from Montana south to central Mexico and west through California.

Habitat: Desert and forest, from coastal areas to higher altitudes.

Diet: Desert cottontails are herbivores, eating mainly grasses but some wood and bark.

Behavior and reproduction: The breeding season for the desert cottontail is from January to August, with multiple litters per year, and an average litter size of two to four babies. They reach sexual maturity at eighty days.

Desert cottontails and people: Hunted by humans mainly for sport.

Conservation status: The desert cottontail is not listed as threatened by the IUCN. ∎

FOR MORE INFORMATION

Books:

Morris, Ting. Rabbit (Animal Families). Mankato, MN: Smart Apple Media, 2004.

National Research Council. "Rabbits." In Microlive-stock: Little-Known Small Animals with a Promising Economic Future. Washington, DC: National Academies Press, 1991. Online at http://books.nap.edu/books/030904295X/html/179.html (accessed on July 12, 2004).

National Research Council. "Domestic Rabbit." In Microlivestock: Little-Known Small Animals with a Promising Economic Future.Washington, DC: National Academies Press, 1991. Onlin at http://books.nap.edu/books/030904295X/html/183.html (accessed on July 12, 2004).

Nowak, Ronald M. Walker's Mammals of the World, 6th ed. Baltimore: Johns Hopkins University Press, 1999.

Swanson, Diane. Welcome to the World of Rabbits and Hares. Portland, OR: Graphic Arts Center Publishing Co., 2000.

Swanson, Diane. Rabbits and Hares (Welcome to the World of Animals). Milwaukee: Gareth Stevens, 2002.

Periodicals:

Angerbjörn, Anders, and John E. C. Flux. "Lepus timidus." Mammalian Species (June 23, 1995): 1–11.

Chapman, Joseph A., and Gale R. Willner. "Sylvilagus audubonii." Mammalian Species (September 21, 1978): 1–4.

Chapman, Joseph A., et al. "Sylvilagus floridanus." Mammalian Species (April 15, 1980): 1–8.

Hacklander, Klaus, et al. "The Effect of Dietary Fat Content on Lactation Energetics in the European Hare (Lepus europaeus)." Physiological and Biochemical Zoology (January 2002): 19–28.

Krebs, Charles J., et al. "What Drives the 10-Year Cycle of Snowshoe Hares?" BioScience (January 2001): 25.

Roach, John. "Rabbit Woes: Easter Icons Face Survival Struggles." National Geographic News (April 17, 2003). Online at http://news.nationalgeographic.com/news/2003/04/0417_030417_rabbits.html (accessed on July 12, 2004).

Web sites:

House Rabbit Society. http://www.rabbit.org (accessed on July 12, 2004).

Myers, Phil, and Anna Bess Sorin. "Family Leporidae." Animal Diversity Web. http://animaldiversity.ummz.umich.edu/site/accounts/information/Leporidae.html (accessed on July 12, 2004).