{{Speciesbox | name = European hamster | status = CR | status_system = IUCN3.1 | status_ref = | genus = Cricetus | parent_authority = Leske, 1779 | species = cricetus | authority = (Linnaeus, 1758) | image = Hamster.jpg | image_caption = Hamster photographed at Vienna Central Cemetery | range_map = CricetusCricetusIUCN.svg | range_map_caption = European Hamster range | synonyms = {{collapsible list |Cricetus albus |Cricetus babylonicus |Cricetus canescens |Cricetus frumentarius |Cricetus fulvus |Cricetus fuscidorsis |Cricetus germanicus |Cricetus jeudii |Cricetus latycranius |Cricetus nehringi' |Cricetus niger |Cricetus nigricans |Cricetus polychroma |Cricetus rufescens |Cricetus stavropolicus |Cricetus tauricus |Cricetus tomensis |Cricetus varius |Cricetus vulgaris |Mus cricetus }} | synonyms_ref = }} The European hamster (Cricetus cricetus), also known as the Eurasian hamster, black-bellied hamster or common hamster, is the only species of hamster in the genus Cricetus''. It is native to grassland and similar habitats in a large part of Eurasia, extending from Belgium to the Altai Mountains and Yenisey River in Russia. Historically, it was considered a farmland pest and had been trapped for its fur. Its population has declined drastically in recent years and is now considered critically endangered. The main threats to the species are thought to be intensive agriculture, habitat destruction, and persecution by farmers. Description The European hamster has brown dorsal fur with white patches. The chest and belly are black. The tail is short and furred. It is much larger than the Syrian or dwarf hamsters, which are commonly kept as pets, and is the largest known species of hamster. It weighs and can grow to long with a tail of . Its dental formula is . Behaviour The common hamster is a nocturnal or crepuscular species. It lives in a complex burrow system. It eats seeds, legumes, root vegetables, grasses and insects. It transports its food in its elastic cheek pouches to the food storage chambers. The storage chambers may be quite large and on average contain of food, but exceptionally can be up to . It hibernates between October and March. During this time, it wakes every five to seven days to feed from the storage chambers. The adults reach sexual maturity when they are about 43 days old and breed from early April to August. The gestation period is 18–20 days and the size of the litter ranges from three to 15 young, which are weaned when aged three weeks. They are usually solitary