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Golden Hamster

Mesocricetus auratus

French: Hamster doré / German: Goldhamster / Spanish: Hamster de Siria

Other common names: Syrian Golden Hamster, Syrian Hamster

Taxonomy. Cricetus auratus Waterhouse, 1839, Aleppo, Syria.

In the past, auratus was considered the only species of Mesocricetus, encompassing brandti, newtoni, and raddei . Mesocricetus auratus has a unique morphology and genetic makeup. Monotypic.

Distribution. Restricted to the Aleppinian Plateau on the border of S Turkey and N Syria between Ebla and Sanliurfa; possibly present in Hatay.

Descriptive notes. Head-body 128-165 mm, tail 13-21 mm; weight 82-175 g. Male Golden Hamsters tend to be larger than females. Body is heavy and thick, tail is short and concealed by fur, eyes are large, and ears are long and rounded. Forefeet are short and thick, hindfeet are elongated, and palms and soles are naked. Expandable cheek pouches extend backward to shoulders. Females have eight pairs of nipples that are evenly spaced from pectoral to inguinal region. Fur is long, dense, and soft. Dorsal pelage is reddish, flanks are yellowish, head is more rufous than back, and some individuals have dark brown spot between ears. Hair bases are dark slate. Belly is grayish or nearly white and washed by slate-gray undercolor. Rufous transverse band with blackish and white areas of variable extent occurs in front of forefeet and across chest. Skull is robust with slightly bowed dorsal profile, long and broad rostrum, constricted orbital region, and heavy zygomatic arches. Auditory bullae are relatively large. Mandible is robust, and processes are powerful. Molars are rooted and low-crowned, and cusps are arranged in two parallel rows. Karyotype is 2n = 44.

Habitat. Grasslands and arable land on sandy clay overlying limestone at elevations of 280-650 m. Habitatis still pristine steppe in Turkey but intensively cultivated in Syria.

Food and Feeding. The Golden Hamster is omnivorous, consuming primarily seeds but also invertebrates. Small particles of food are stuffed into cheek pouches and transported into a burrow, where they are emptied by pressing items out with paws.

Breeding. Under controlled conditions, ovulation of the Golden Hamster is triggered by daylight longer than 12-5 hours. In the wild, reproduction probably starts in February. Mating system is polygynous, and reproductively mature females are in estrus every four days. Gestation lasts 16-19 days, parturition takes 1-5-2-5 hours, and litter sizes are 4-16 young, usually 6-12 (average nine). Young are born hairless, blind, and deaf. Their eyes open after 12-14 days, and weaning occurs at 19-21 days old. Females are sexually mature at 26-30 days old and males at 42-48 days. Captive females can give birth every month. Lifespan is up to two years in wild and up to 3-5 years in captivity.

Activity patterns. The Golden Hamster is nocturnal. Although not a true hibernator, it gets torpid below ambient temperature of 8°C. Wild hamsters are probably lethargic between November and mid-February. Captive hamsters kept under natural conditions remained torpid for ¢.5 months from mid-October to mid-March. Adult individuals start hibernating earlier and stay torpid longer. The Golden Hamster is terrestrial and digs burrows 4-5 cm in diameter. From the entrance, the burrow leads into a vertical tunnel that descends to depths of 36-106 cm. Spherical breeding chamber has a diameter of 10-20 cm and contains a nest of dry plant matter, occasionally with bird feathers. At least two tunnels divert from this chamber. A short and blind tunnel is presumably used for urination, but there is no evidence of a latrine. Total lengths of tunnels per burrow are 0-9-9 m or more.

Movements, Home range and Social organization. The Golden Hamsteris solitary and territorial. Territory is marked by rubbing flank glands against a substrate. Estrous females increase frequency of vaginal marking. Hamsters are highly aggressive outside the reproductive season, and males frequently produce teeth chattering during encounters with other males. Home range size has been not assessed, but closest distance between occupied burrows was 118 m.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. The Golden Hamster has a small area of occupancy, which is definitely less than 20,000 km?®. Continuous habitat loss, pest-control measures, and population declines are conservation threats. So far only eleven sites of occurrence have been identified with certainty. Information on density is contradictory. A field survey found only 0-2 burrows/ha, but skeletal remnants were common in diets of owls. The Golden Hamster is widely used as experimental animal and kept as pets. Captive populations originate from a single litter excavated in 1930, but additional wild animals were added in 1971. Various types were selected among pet hamsters that differ in color and length of hair. For welfare of captive hamsters, a cage with a minimal ground floor area of 10,000 cm® and deep (40 cm) bedding is recommended.

Bibliography. Fischer et al. (2007), Gattermann et al. (2001), Krystufek & Vohralik (2009), Neumann et al. (2006), Romanenko et al. (2007), Siegel (1985), Terada & Ibuka (2000).