Are hamsters solitary?

In the complicated world of #properhamstercare, new and experienced hamster owners alike are combatting the deep burrows of the internet when trying to find even the simplest information.

One of the most common questions is: can hamsters live together?

The short answer is no. Including dwarf and roborovski hamsters.

Some things to remember as we explore the research:

• Hamsters aren't humans and don't get lonely

• Hamsters are a widely under-researched animal, so we have to be willing to be corrected and update our own knowledge

So what does the research tell us about hamsters being solitary?

In VetRecord, Hedley, Pettitt and Abeyesinghe published 'Preliminary investigation into the housing of dwarf hamsters' (1 August 2023). They discovered that, contrary to popular belief, in the wild Campbell's dwarves were not found to share the same burrow. This is contradictory to many breeders who suggest that pairs of pure bred Campbell's dwarf hamsters can cohabit happily.

They further found differences between Sungorus (winter white) dwarves and between the sexes from former research and observations of dwarf hamsters in the wild. For example, Campbell's males were more likely to show aggression towards one another in the wild, while Sungorus females were more likely to show aggression towards one another. There was even a consideration into the season, which appears to affect the aggression levels on Sungorus males in winter specifically.

Simply considering this plethora of new information into the different sexes and species leads us at Happy Hamsters UK to a foregone conclusion that no dwarf hamsters should be housed together. This is also based on the fact that the majority of dwarf hamsters in the UK are bought from pet shops, or rehomed from rescues so therefore will have hybrid genes.

Based on the unpredictability of the two species which make up a hybrid (Campbell's and Sungorus), it would be common sensical to house all dwarf hamsters alone. Please note that we are commenting on the wild observations, and not the remainder of the study.

While this study is very interesting, there is a bias recognised that the survey was shared in ethical care groups, where many owners already house their hamsters by themselves. The number of owners who had had co-housing failures and successes were unfortunately not conclusive enough for us to comment on. The study also references incorrect minimum care standards.

Much of our thoughts on whether hamsters are solitary or not comes from the unpredictability of hamsters generally, and the lack of research finding pairs or groups of hamsters living together happily in any environment.

From a 2015 study on how 'vocalizations convey sex, seasonal phenotype, and aggression in a seasonal mammal' which recorded noises made by hamsters of different sexes, it was proven that non-reproductive Sungorus hamsters - meaning female pairs or male pairs - demonstrate increased aggression compared with reproductive hamsters aka male/female pairs.

Even a hamster's basic anatomy promotes an independent lifestyle. From a 1992 study into Campbell's dwarves entitled 'Field studies of chemical signalling: direct observations of dwarf hamsters (Phodopus) in Soviet Asia', it was noted that they have 'musk glands' in the corners of their mouth, which means that they scent mark each piece of food when they put it into their pouch. This claims it as their own, therefore not welcoming a group eating environment.

Furthermore, the California Hamster Association created content referencing the benefits of co-housing on breeding and raising dwarf and roborovski hamster litters. They acknowledged that there is little research on roborovski species, but concluded based on little evidence that roborovskis would live together in the wild. The referenced study 'Species composition and interspecific behavior affects activity pattern of free-living desert hamsters in the Alashan Desert' states that 'Phodopus live in pairs or alone', and goes on to mention that the pairs produce up to 4 litters per year. This suggests female/male pairs, but not same sex pairs.

Finally, on a less contested note, we consider the solitary nature of Syrian hamsters. From studies and observations of wild Syrian hamsters, it's generally agreed that they are largely solitary, inhabiting burrows alone and defending their home territories against others. In a 2017 study which attempts to suggest that Syrian hamsters could be housed socially, Social housing and social isolation: Impact on stress indices and energy balance in male and female Syrian hamsters, weight and impact on the thymus gland (which supports hamsters' immune systems) were monitored in social and solitary housed Syrian hamsters. Food consumption and weight was generally higher in socially housed hamsters, and they displayed modest thymus gland involution.

The one variable that was not taken into account in this particular study was stimulus. They saw increased 'anxiety' behaviours in solitary female Syrians when separated from littermates, but there was a bias in this study in that both the socially and solitarily housed hamsters were given the same basic level of stimulus. From our personal experience of rescuing co-housed Syrian hamsters and raising litters born in our care, we find that as long enough mental and physical stimulation is provided to the hamsters, they display no more anxiety-like behaviours once separated.

To conclude, it would be best to house all species of hamsters alone. Every study, regardless of intent and purpose, found that hamsters can live happily alone. The risks to hamsters housed together, from fighting to weakened immune systems, prove that it is safer to keep hamsters alone.

To answer the question: can hamsters live together? No they cannot!