Co-housing dwarf hamsters

Hamsters are commonly kept as pets and whilst syrian and chinese hamsters are kept alone, dwarf hamsters are still commonly kept in  same sex pairs or small groups. Even when this goes against findings of the natural history of dwarf hamsters. For instance, Russian dwarf hamsters have been found to not share the same burrow with a member of the same sex.

But there has also now been research done by the Royal Veterinary College that supports the need for dwarf hamsters to be housed alone. Of the 248 Dwarf hamster keepers included in the study, 148 (59.6%) were reported as always being housed individually and 25 (10.1%) being reported as always being housed with other dwarf hamsters. The remaining 75 (30.24%) were reported as being previously housed with other dwarf hamsters but were currently being housed individually. 65 out of these 75, were separated due agnostic behavious, which included fighting, biting, screaming/squeking and scratching. The remaining 10 were separated due to other reasons such as to avoid breeding or due to a companions death. 

The study found a significant association between age group and co-housing, with hamsters over the age of 6 months being 4.75 times more likely to have experienced co-housing failure than hamsters younger than 6 months. This may be partly explained by the fact older an animal is, the more likely it is to experienced any event in its life due to there being more time for this event to have occurred. These could also be explained by the majority of hamsters being reported as being kept with their litter mates, so in natural conditions, the offspring would have dispersed from their parent’s burrows at approximately 18 days of age. So it would be expected that the frequency of agnostic behaviour would increase over time if the hamsters were continued to be kept together past this point, assuming there has been no alteration in behaviour with selection. 

The questionnaire was distributed among hamster keepers who may have had more knowledge of dwarf hamster husbandry than the general population of dwarf hamster owners, so the results may have been more alarming if the only included owners who followed the advice of pet shops. Therefore, the research shows that it is more beneficial for the welfare of dwarf hamsters for them to be housed alone.