Roborovski dwarf hamster

Roborovski hamster
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Family:	Cricetidae
Subfamily:	Cricetinae
Genus:	Phodopus
Species:	P. roborovskii
Binomial name
Phodopus roborovskii ( Satunin , 1903)
Distribution of P. roborovskii
Synonyms
Cricetulus bedfordiae Thomas, 1908 Phodopus praedilectus Mori, 1930

The Roborovski hamster (Phodopus roborovskii), also known as the desert hamster, Robo dwarf hamster or simply dwarf hamster is the smallest of three species of

The Roborovski hamster has been found to be more common in the southern area of its distribution range, in areas such as Yulin, Shaanxi, China. It has been reported as a common sighting by locals in this city and in the sand dunes of the Ordos Desert.^[10]

Diet

They are omnivorous; they primarily eat grains, vegetables, fruit, and plants, but they will also eat meat and insects when present. Roborovski hamsters remain underground in winter and survive in that season by stockpiling some food in warmer weather and storing it in special food chambers within their burrow system. In the Chinese province of Shaanxi it is known for foraging millet seeds.^[11]

In Mongolia,

The daily dietary intake of the Roborovski hamster heavily depends on its body weight. Juveniles have higher intakes of food compared to their weight than adult hamsters. Based on its population structure, Wan et al. calculated an average food intake of ca. two gram plant seeds per day. They specify the functional relation between the daily food intake (N) and the body-weight (M) to be ${\displaystyle N=(1{,}422\cdot \ln(M/{\text{gram}})-1{,}780){\text{ gram}}}$[15]

Pups, juveniles as well as adult hamsters, are foraging food in their burrows.^[16]

History of human contact

Russian expeditioner Lt.

Currently, 10 variations of Roborovski hamsters are thought to exist.[24]^[25] Only one is standardised in the UK as of 2018 as per UK National Hamster Council, with 4 genes recognised and others still under dispute.

• Agouti — a natural grayish-brown with white underside and "eyebrows" (white over eyes)
• White face — a dominant mutation producing an agouti-coloured hamster with a white face
• Husky — a recessive mutation producing a white-faced hamster with a paler, more dilute top coat and no dilution on the undercoat.
• "mottled" or "pied" — both dominant and recessive mutations have been identified, these hamsters are white with the agouti colouring (or husky/blue/black/cinnamon) in irregular patches over their heads, bodies and sometimes their faces.
• Head spot — a combination of the dominant and recessive pied genes that creates a pure white animal with one patch of colour on the head
• White-from-white-faced or dark-eared white — a combination of the dominant white-faced gene and the husky gene that produces a white hamster that retains a greyish undercoat and ears.
• White-from-pied or pure white — is allegedly a combination of the two pied genes producing a white hamster. Note that two recessive pied genes do not make white.
• Black-eyed white is a new gene that has proven not to be white from pied or white from white-faced. This gene is still being explored.
• Red-eyed — a recessive mutation that produces a cinnamon-coloured hamster with a chocolate undercoat, dark red eyes, and pale ears. Adding pied to a cinnamon gives brighter red eyes. This is not the same mutation as 'brown eye' or rust.
• Black/blue - Originally bred in Finland, going to the Netherlands and then Germany. Black and blue are two recessive genes still being investigated. These genes came to the UK in 2017 via Doric Hamstery and the first UK litter of blacks were born there Spring 2018. Both are thought to be self colours behaving like melanistic and its further dilution to blue that is already found in other species.^[26]

Breeding in captivity has also produced a darker variation of the naturally sandy-coloured agouti fur. According to Fox (2006) white-faced and derived breeds are considered torture-breeding and therefore breeding them is forbidden by law in several European countries like Germany or Austria. The homozygous carrier of the gene variant causes neurological symptoms similar to the whirling disease, where the animal spins itself around until it dies of exhaustion.^[27][28]

This concern is not seen in recessive white face (husky).

Breeding

The sex of a Roborovski is determined visually; female openings are very close together and may even look like a single opening, while male openings are further apart. Males usually have a visible scent gland near the navel above the two openings, appearing as a yellow stain in older animals.

The breeding season for the Roborovski hamster is between April and September. Gestation lasts from 20 and 22 days, producing three to four litters. The litter size is between three and nine, with an average of six.^[6] Captive-bred Roborovski often breed year round.

The offspring weigh 1.2 grams (0.042 oz)–2 grams (0.071 oz) at birth.

As pets

Roborovski hamsters have become increasingly popular as pets in recent years. They are best suited to life as merely observational creatures, with limited interaction between them and humans, due to their increased activity levels that lead to a high stress predisposition and decreased ease of handling when compared to other domestic hamster species. However, they can be tamed with time.^[31]

On average, Roborovski hamsters will live 26 months in captivity.^[31]

Although claimed to be hypoallergenic, Roborovski hamsters have been associated with the development of asthma in previously asymptomatic owners.^[32]

In rare emergency situations, a shallow dish of warm water may be necessary to clean harmful substances from a hamster's fur; however, under normal circumstances, hamsters should never be bathed in water as, aside from being incredibly stressful, this can remove vital protective oils from their coat, which can be dangerous and potentially fatal.^[33][34] Hamsters frequently groom themselves, and instead of water, a sand bath should be offered to help them stay clean and healthy.^[35]

Housing

Unlike other species of hamster (see 'Syrian hamster behavior'), Roborovski hamsters can sometimes be kept in same-sex pairs or small groups if raised together from a young age.^[36][37] A single or pair of Roborovski hamsters should be kept in a cage of minimum 50 x 100 cm, or the equivalent of 0.5 sq metres^[38][39] with at least 15–20 cm of substrate, so that they may exercise their natural urge to burrow.^[40][41] However, greater floor space and substrate depth is recommended for all species of hamsters, where "bigger is always better" .^[39] Additional levels do not count toward the base area.^[42] Aquariums and DIY enclosures are commonly used amongst hamster enthusiasts, often preferred for their capability to hold greater amounts of substrate, availability, and cost, amongst various other reasons, over traditional wire cages (see images for examples).^[43]

If fighting within a group occurs, the hamsters should be separated immediately to avoid injury. Roborovski hamsters are very active, so a species-appropriate wheel is a necessity.^[44] Size is still debated, but the general consensus is that a wheel should be at least 16.5 cm (6.5 inches.^[44] Other sources recommend a minimum diameter of 20 cm(8 inches).^[45]

Roborovski hamsters, like many rodents, will naturally avoid large open spaces, opting to stick close to the walls if forced into the open, where they feel safest. Providing them with multiple hiding spots is vital. This can be achieved by placing branches, tunnels and various other hides in close arrangement.

Food

Based on their natural diet, owners should feed hamster food containing mainly

To support their natural behaviour of foraging and stockpiling, feed should be scattered around the enclosure, hidden in several spots, or slightly buried beneath the substrate (approximately 1tsp of food per hamster per day).^[46]

Foods to avoid include:^[47]

• Leafy green parts of a tomato (toxic)
• Meats which are high in fat
• Chocolate or candy
• Onions, garlic and bell peppers (can cause stomach irritation)
• All citrus fruits (too acidic)
• Apple seeds
• Eggplant

Fresh water should be available at all times. A bowl is preferable to a bottle, as it encourages a more natural and comfortable drinking posture.^[46]

Hamsters' incisors never stop growing and they have a ‘self-sharpening’ system where the incisors grind against each other while gnawing, which wears the teeth down; so chew toys are essential.^[48]

Bedding/Substrate

Nesting materials should be easily shreddable and digestible, such as unscented toilet paper, moss, hay or leaves.^[49]

Avoid materials that separate into thin strands when chewed (such as

Sand must be dust-free.[41] Chinchilla sand is too dusty for hamsters and can cause respiratory problems. Bird sand is also not suitable as it contains shards of broken shell.^[41]

In film

The short film Roborovski, about a hamster, co-written and directed by

Gallery

References

Further reading

• Lissenberg, J. Dwerghamsters. Aanschaf, verzorging, Voeding, Fokken Zuidboek Producties: Lisse, The Netherlands: 2002
• Verhoeff-Verhallen, E. Konijnen en Knaagdieren Encyclopedie Rebo Productions: Lisse, The Netherlands: 1997

External links

Wikispecies has information related to Phodopus roborovskii.

Wikimedia Commons has media related to Phodopus roborovskii.

• Animal Diversity Web - Phodopus roborovskii