Syrian hamsters, also called Golden hamsters, are the most common species, and the largest of the species. They come in a variety of colors, though the most common is a golden, light brown coat with black spots and a white underbelly. They also have beady eyes, large ears, and short tails. [2] X Research source Syrian hamsters should never be kept together as they are territorial and solitary creatures. These aggressive tendencies start to develop when Syrian hamsters are between 6 and 8 weeks old. Once they reach 8 weeks, they should be housed on their own in separate cages. [3] X Research source Dwarf hamsters are the second most common species and are smaller than Syrian hamsters. Dwarf hamsters have a dark strip of fur running from their head down to their tail and are often brown in color, unless they are albino, then they will be all white. [4] X Research source Dwarf hamsters usually prefer to live socially, in pairs or groups. But their sociability varies, and some dwarf hamsters prefer to live alone. Chinese Dwarf hamsters are the third most common species. They are small, about 4–5 inches (10–13 cm) long, with silky gray-brown fur and black stripes down their backs. These hamsters are sometimes mistaken for mice, as they have longer tails than other hamster species. Their long tails make them great jumpers and climbers. They enjoy human interaction, but don’t usually play well with other hamsters, so keep only one per a cage. They are also nocturnal, so they will run around and make noise at night. [5] X Research source Please note that there is no such thing as hamster breeds. There are only hamster species and colorings.

If you want to try to keep hamsters of different genders in the same cage, introduce them when they are young.

Before you put them in the same cage, make sure the cage is neutral and does not contain the scent of either hamster. The cage should be clean or new, have clean bedding, and clean toys. This will give the hamsters fewer things to fight over and dissuade them from fighting over territory.

Do not leave your hamsters alone in their cage until you are satisfied that they are tolerating each other. You should feel they are not physically dangerous to one another or likely to harm each other. If you are not sure if they are getting along, remove them from the same cage and place them back in separate cages. Try placing them together again the following day and watch them interact for signs they are getting along.

One hamster may jump on top of the other hamster until the bottom hamster squeaks in submission. The hamster on top, now confirmed dominant, should then release the bottom hamster. These displays of dominance can happen over and over, and as long as the hamsters get up and resume their activities, it’s normal. Normal squabbling can occur for a few weeks when the hamsters are first placed in a cage together, and may happen over the course of the hamsters’ lives. [7] X Research source Avoid interfering with your hamster when they are squabbling or removing one hamster from the cage and then putting her back in the cage again. As long as the hamsters are squabbling, you should let them respond to each other on their own. Pulling one hamster out of the cage can create confusion and stress out your hamsters. [8] X Research source

One hamster may cause injury to the other hamster and prevent the bullied hamster from eating, drinking, or sleeping. A bullied hamster may become withdrawn, lose or gain weight and stop playing with the other hamster or with you. She may also even become aggressive towards you when you hold her or touch her. These are all signs of severe distress, and you will likely need to adjust the bullied hamster’s living space or separate her from the other hamster. [10] X Research source

Once you move the bullied hamster to a new cage, try to keep the new cage as close to her old cage as possible. This will allow her to transition more easily to the new cage and reduce her stress levels. [11] X Research source

Talk to a sales associate at your local pet store to find a cage that is large enough to keep both hamsters happy and stress free.

There should also be no narrow corners or sections in the cage to prevent the hamsters from getting stuck or blocked in.

Having two beds is important, as most hamsters do not like sharing beds. If possible, you should also provide two sets of toys, like two wheels or two boxes with two entrances. You should also provide two large food dishes for the hamsters, large enough to fit one hamster in the dish. Most hamsters like to sit in their food dish and don’t like to fight for space in the same dish.