Mongolian gerbils, or Mongolian jirds, occur naturally in the highlands of Inner Mongolia. They are also found in adjacent parts of southern Siberia and northern China, including Sinkiang and Manchuria provinces.

Currently Meriones unguiculatus is a popular housepet and is widely used in research. It can be found worldwide in a variety of locales and environments (Agren et al. 1989).

Biogeographic Regions: palearctic (Native )

Mongolian jird body length averages 120 mm long, tail length may range up to 120 mm. The fur is thin, with grey roots, a yellow shaft, and a black tip. Ventral fur is white and their unfurred claws reveal their pink/white skin.

Males are slightly larger than females, with males averaging 60 grams and females averaging 50-55 grams (van Veen 1999).

Range mass: 52 to 133 g.

Average mass: 96 g.

Average basal metabolic rate: 0.546 W.

• Terrestrial

Mongolian gerbils live in the highlands in Inner Mongolia. Climate in these regions is extreme, temperatures can vary from -40 degrees Celsius in the winter to 50 degrees Celsius in the summer. These areas are characterized by low annual precipitation (less than 230 mm a year) and a long winter (October to April).

Gerbils, or jirds, live in clay or sandy deserts, grasslands, scrub, arid steppes, and mountain valleys.

They live in family groups in small burrows dug into soft soil. Gerbils build burrows near a plant to take advantage of the support of the plant's roots (Agren et al. 1989). M. unguiculatus burrows are characterized by one nest and one to two storerooms, the burrows extend 0.45-0.60 meters underground and average 4cm in diameter.

Terrestrial Biomes: desert or dune ; savanna or grassland ; mountains

Mongolian gerbils feed mainly on mugwort (Artemisia sieversiana and A. commutata). Saltwort (Salsola collina), bristle grass (Setaria viridis), and lyme grass (Leymus chinensis) are also eaten.

Gerbils conserve both water and fat extremely well. They conserve water by producing a highly concentrated urine and dry feces.

Captive mongolian gerbils eat a wide variety of foods, including grains, grasses, and some fruits and vegetables. (Agren et al. 1989)

Average lifespan

Status: captivity: 2.0 years.

Wild mongolian gerbils breed between February and October, producing up to three litters. The estrus cycle lasts 4-6 days and a post-partum estrus can occur. Gestation lasts between 19 and 30 days. Litter size varies between 1 and 12, but averages 4 to 7. Newborn young weigh about 2.5 grams each and weaning occurs at 20-30 days. Sexual maturity is reached at between 65 and 85 days old and breeding can continue until 20 months of age, though average lifespan in the wild is 3-4 months (Nowak, 1991).

Average birth mass: 3 g.

Average gestation period: 25 days.

Average number of offspring: 5.

Average age at sexual or reproductive maturity (male)

Sex: male: 36 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 43 days.

Mongolian gerbil populations are stable.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: least concern

Mongolian gerbils are not extensive agricultural pests. Escaped captive gerbils may become established in new areas and pose a threat to native wildlife through competition and disease introduction. Gerbils, similar to other rodents, may serve as disease vectors.

(Agren et al. 1989)

Mongolian gerbils are useful research animals and have become very popular in the pet trade. They are easy to take care of, get along well with other gerbils (when introduced to each other early), require very little maintenance, and are tremendously cute and fun to play with. The first documented pet Mongolian gerbil lived in the United Kingdom in 1961. (van Veen 1999).